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Sample records for 10-bis 2-naphthyl anthracene

  1. White organic light-emitting diodes with 9, 10-bis (2-naphthyl) anthracene

    NASA Astrophysics Data System (ADS)

    Guan, Yunxia; Niu, Lianbin

    2009-03-01

    White organic light-emitting diodes were fabricated by 9, 10-bis (2-naphthyl) anthracene (ADN) doped with Rubrene with a structure of ITO/copper phthalocyanine (CuPc) / NPB /ADN: Rubrene /Alq3 /CsF/Mg:Ag/Ag. Multilayer organic devices using AND and Rubrene as an emitting layer produced white emissions with good chromaticity and luminous efficiency as high as 5.93 cd/A. This performance can be explained by Förster energy transfer from the blue-emitting host to the orange-emitting dopant.

  2. Improved efficiency for green and red emitting electroluminescent devices using the same cohost composed of 9,10-di(2-naphthyl) anthracene and tris-(8-hydroxyquinolinato) aluminum

    NASA Astrophysics Data System (ADS)

    Zhu, Jianzhuo; Li, Wenlian; Chu, Bei; Yang, Dongfang; Zhang, Guang; Liu, Huihui; Chen, Yiren; Su, Zisheng; Wang, Junbo; Wu, Shuanghong

    2009-12-01

    We demonstrate highly efficient green and red fluorescence dyes-doped electroluminescent devices using cohost strategy. The cohost system is composed of tris-(8-hydroxyquinolinato) aluminum (Alq) and 9,10-di(2-naphthyl) anthracene (ADN). The maximum current efficiencies are increased by 54% and 104% for green and red devices by optimizing the ratio between ADN and Alq in the cohost compared to the conventional Alq single-host devices, respectively. We attribute the improvement of efficiencies to balanced hole and electron injection into the emitting layer, the enlarged width of recombination region and the multiple emission processes.

  3. Correction: Large-size nanosheets of 9,10-bis(phenylethynyl)anthracene with high photoresponse and light emission anisotropy.

    PubMed

    Wang, Juan-Ye; Peng, Hong-Dan; Yang, Jia-Mei; Yan, Jing-Hui; Pan, Ge-Bo

    2016-04-28

    Correction for 'Large-size nanosheets of 9,10-bis(phenylethynyl)anthracene with high photoresponse and light emission anisotropy' by Juan-Ye Wang et al., Phys. Chem. Chem. Phys., 2016, DOI: 10.1039/c5cp05507e. PMID:27057919

  4. Improved efficiency in organic light-emitting devices with tris-(8-hydroxyquinoline) aluminium doped 9,10-di(2-naphthyl) anthracene emission layer

    NASA Astrophysics Data System (ADS)

    Yuan, Yongbo; Lian, Jiarong; Li, Shuang; Zhou, Xiang

    2008-11-01

    Organic light-emitting devices with tris-(8-hydroxyquinoline) aluminium (Alq3) doped 9,10-di(2-naphthyl) anthracene (ADN) as the emission layer (EML) have been fabricated. These devices exhibit efficient electroluminescence (EL) originated from the Alq3 as the mass ratio of Alq3 to ADN was varied from 1 to 50%. The devices with an optimal Alq3 mass ratio of 10 wt% showed a peak EL efficiency and an external quantum efficiency of 9.1 cd A-1 and 2.7% at a luminance of 1371 cd m-2, which is improved by a factor of 2.2 compared with 4.1 cd A-1 and 1.2% at a luminance of 3267 cd m-2 for conventional devices with the neat Alq3 as the EML.

  5. The role of charge-transfer integral in determining and engineering the carrier mobilities of 9,10-di(2-naphthyl)anthracene compounds

    NASA Astrophysics Data System (ADS)

    Tse, S. C.; So, S. K.; Yeung, M. Y.; Lo, C. F.; Wen, S. W.; Chen, C. H.

    2006-05-01

    The charge transporting properties of t-butylated 9,10-di(2-naphthyl)anthracene (ADN) compounds have been investigated experimentally and computationally in relation to their molecular structures. The ADN compounds are found to be ambipolar with both electron and hole mobilities in the range of 1-4 × 10 -7 cm 2 V -1 s -1 (electric field 0.5-0.8 MV/cm). As the degree of t-butylation increases, the carrier mobility decreases progressively. The mobility reduction was examined by Marcus theory of reorganization energies. All ADN compounds possess similar reorganization energies of ˜0.3 eV. The reduction of carrier mobilities with increasing t-butylation can be attributed to a decrease in the charge-transfer integral or the wavefunction overlap.

  6. Highly Efficient and Stable Red Organic Light-Emitting Devices Using 9,10-Di(2-naphthyl)anthracene as the Host Material

    NASA Astrophysics Data System (ADS)

    Tang, Hao; Li, Ying; Wang, Xiuru; Wang, Wengen; Sun, Runguang

    2007-04-01

    We present red organic light-emitting devices (OLEDs) with high efficiency and stability based on a wide band gap host material 9,10-di(2-naphthyl)anthracene (ADN). In these devices, N,N'-bis(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4,4'-diamine (NPB) and tris(8-hydroxy-quinoline) aluminum (Alq) were used as hole and electron transport layers, respectively. Coumarin 6 (C6) and 4-(dicyano-methylene)-2-t-butyl-6-(1,1,7,7-tetramethyl-julolidyl-9-enyl)-4H-pyran (DCJTB) were co-doped into the ADN emitting layer. Utilizing the two-step energy transfer from ADN to C6 and then from C6 to DCJTB, we achieved pure red organic light-emitting devices, which showed improved optical and electrical characteristics. Compared with devices where the emitting layer is composed of Alq and DCJTB, the emission efficiency and stability of the co-doped ADN-based devices are greatly improved and the turn-on voltage is also decreased. The co-doping technique provides a promising way to utilize wide band gap materials as the host to make red OLEDs, which will be useful in improving the EL performance of devices and simplifying the process of fabricating full-color OLEDs.

  7. Piezoflurochromism and Aggregation Induced Emission Properties of 9, 10-bis (trisalkoxystyryl) Anthracene Derivatives.

    PubMed

    Duraimurugan, Kumaraguru; Sivamani, Jayaraman; Sathiyaraj, Munusamy; Thiagarajan, Viruthachalam; Siva, Ayyanar

    2016-07-01

    We report the synthesis of trisalkoxy substituted 9, 10-bis styrylanthracene derivatives (C8-ant and C12-ant) by Heck coupling with very good yield and their photophysical properties. Both C8-ant and C12-ant exhibit aggregation induced emission (AIE), mechnoflurochromism and thermochromism. Trisubstituted 9, 10-distyrylanthracene molecules having all the luminescent properties in a single molecule are first of its kind.

  8. Encapsulation with the protrusion of cruciform 9,10-bis(arylethynyl)anthracene derivatives in a self-assembled boronic ester cavitand capsule: photochemical and photophysical properties.

    PubMed

    Hirumi, Yohei; Tamaki, Kento; Namikawa, Tomotaka; Kamada, Kenji; Mitsui, Masaaki; Suzuki, Kengo; Kobayashi, Kenji

    2014-05-01

    The self-assembled boronic ester cavitand capsule 3 quantitatively and tightly encapsulates 2,6-diacetoxy-9,10-bis(arylethynyl)anthracene derivatives 4 a-4 c as highly fluorescent cruciform guests to form complexes 4 a@3, 4 b@3, and 4 c@(3)2. The structural features of capsule 3, which possesses two polar bowl-shaped aromatic cavity ends and four large equatorial windows connected by dynamic boronic ester bonds, made it possible to encapsulate cruciform 4 with protection of the reactive anthracene core inside the capsule and with two protruding arylethynyl groups, the π-conjugated arms of compound 4, through two of the equatorial windows of the capsule. Thus, complexes 4 a@3, 4 b@3, and 4 c@(3)2 show greater resistance to photochemical reactions in solution and fluorescence quenching in the powder state compared to free guests 4. In addition to the improved photostability, restriction of the free rotation of the arylethynyl groups of guests 4 upon encapsulation results in sharpening of the UV/Vis absorption peaks with a red-shift and a significant increase in some of the two-photon-absorption peaks of complexes 4 a@3, 4 b@3, and 4 c@(3)2 compared with free guests 4. PMID:24616396

  9. Relationship between molecular stacking and optical properties of 9,10-bis((4-N,N-dialkylamino)styryl) anthracene crystals: the cooperation of excitonic and dipolar coupling.

    PubMed

    Li, Feng; Gao, Na; Xu, Hai; Liu, Wei; Shang, Hui; Yang, Wenjun; Zhang, Ming

    2014-08-01

    Five 9,10-bis((4-N,N-dialkylamino)styryl) anthracene derivatives (DSA-C1-DSA-C7) with different length alkyl chains were synthesized. They showed the same color in dilute solutions but different colors in crystals. The absorption, photoluminescence, and fluorescence decay indicate that there exist both excitonic and dipolar coupling in crystals of DSA-C1-DSA-C7. X-ray crystallographic analysis revealed that all the crystals belong to the triclinic space group P1 with one molecule per unit cell and that the molecules in every crystal have the identical orientation. This offers ideal samples to investigate the impact of the molecular stacking on the optical properties of the crystals. For the first time, the cooperation of excitonic and dipolar coupling has been comprehensively studied, and the contribution to the spectral shift from the excitonic and dipolar couplings quantitatively obtained. The experiments of amplified spontaneous emission (ASE) together with measurements of the quantum efficiency further confirmed this interpretation. The results suggest that the excitonic and dipolar couplings between the adjacent molecules are both important and jointly induce the spectral shifts of the crystals.

  10. Studies of the degradation mechanism of organic light-emitting diodes based on tris(8-quinolinolate)aluminum Alq and 2-tert-butyl-9,10-di(2-naphthyl)anthracene TBADN

    NASA Astrophysics Data System (ADS)

    Jarikov, Viktor V.; Kondakov, Denis Y.

    2009-02-01

    Previously, radical cation of tris(8-quinolinolate)aluminum (Alq•+) has been associated with the instability of Alq films subjected to holes-only electrical current. Yet, the questions remain (i) whether Alq•+ is the primary source of the intrinsic degradation of bipolar organic light-emitting diodes (OLEDs) based on Alq, (ii) whether Alq•+ reactions result in deep charge traps in holes-only devices as found in bipolar counterparts, and (iii) whether radical cations can be a common source of degradation of OLEDs irrespective of materials. With regards to generality of hole-current-related degradation, it is interesting to examine the behavior of 9,10-diarylanthracenes (DAAs)—the practically important class of blue-fluorescing light-emitting-layer hosts. These questions prompted our comparative study of the effects of unipolar currents in Alq and 2-t-butyl-9,10-di(2-naphthyl)anthracene (TBADN), which was chosen as a representative material of the DAA class. First, we identified device structures allowing for rigorous and stable unipolar conduction. Interestingly, even in pristine holes-only devices, our voltammetric measurements indicated that Alq contains a substantial density of deep hole traps (far deeper than what can be explained by energetic disorder), which can be charged by passing holes-only current and seemingly discharged by exposure to white light. As for aged holes-only Alq devices, they exhibited symptoms qualitatively matching those of aged bipolar Alq devices, viz., photoluminescence (PL) loss, transition voltage (V0) rise, and drive voltage (Vd) rise. Notably, PL and V0 are linearly correlated in both holes-only and bipolar devices, which reinforces the supposed link between Alq•+ and the degradation in both types of devices. Yet, there are indications the Alq•+ instability may not be the only degradation pathway in bipolar devices. Even though our observations for holes-only Alq devices agree qualitatively with previously reported ones

  11. Anthracene

    Integrated Risk Information System (IRIS)

    Anthracene ; CASRN 120 - 12 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effect

  12. Tetrahydro-2-naphthyl and 2-Indanyl Triazolopyrimidines Targeting Plasmodium falciparum Dihydroorotate Dehydrogenase Display Potent and Selective Antimalarial Activity

    PubMed Central

    2016-01-01

    Malaria persists as one of the most devastating global infectious diseases. The pyrimidine biosynthetic enzyme dihydroorotate dehydrogenase (DHODH) has been identified as a new malaria drug target, and a triazolopyrimidine-based DHODH inhibitor 1 (DSM265) is in clinical development. We sought to identify compounds with higher potency against Plasmodium DHODH while showing greater selectivity toward animal DHODHs. Herein we describe a series of novel triazolopyrimidines wherein the p-SF5-aniline was replaced with substituted 1,2,3,4-tetrahydro-2-naphthyl or 2-indanyl amines. These compounds showed strong species selectivity, and several highly potent tetrahydro-2-naphthyl derivatives were identified. Compounds with halogen substitutions displayed sustained plasma levels after oral dosing in rodents leading to efficacy in the P. falciparum SCID mouse malaria model. These data suggest that tetrahydro-2-naphthyl derivatives have the potential to be efficacious for the treatment of malaria, but due to higher metabolic clearance than 1, they most likely would need to be part of a multidose regimen. PMID:27127993

  13. Tetrahydro-2-naphthyl and 2-Indanyl Triazolopyrimidines Targeting Plasmodium falciparum Dihydroorotate Dehydrogenase Display Potent and Selective Antimalarial Activity.

    PubMed

    Kokkonda, Sreekanth; Deng, Xiaoyi; White, Karen L; Coteron, Jose M; Marco, Maria; de Las Heras, Laura; White, John; El Mazouni, Farah; Tomchick, Diana R; Manjalanagara, Krishne; Rudra, Kakali Rani; Chen, Gong; Morizzi, Julia; Ryan, Eileen; Kaminsky, Werner; Leroy, Didier; Martínez-Martínez, María Santos; Jimenez-Diaz, Maria Belen; Bazaga, Santiago Ferrer; Angulo-Barturen, Iñigo; Waterson, David; Burrows, Jeremy N; Matthews, Dave; Charman, Susan A; Phillips, Margaret A; Rathod, Pradipsinh K

    2016-06-01

    Malaria persists as one of the most devastating global infectious diseases. The pyrimidine biosynthetic enzyme dihydroorotate dehydrogenase (DHODH) has been identified as a new malaria drug target, and a triazolopyrimidine-based DHODH inhibitor 1 (DSM265) is in clinical development. We sought to identify compounds with higher potency against Plasmodium DHODH while showing greater selectivity toward animal DHODHs. Herein we describe a series of novel triazolopyrimidines wherein the p-SF5-aniline was replaced with substituted 1,2,3,4-tetrahydro-2-naphthyl or 2-indanyl amines. These compounds showed strong species selectivity, and several highly potent tetrahydro-2-naphthyl derivatives were identified. Compounds with halogen substitutions displayed sustained plasma levels after oral dosing in rodents leading to efficacy in the P. falciparum SCID mouse malaria model. These data suggest that tetrahydro-2-naphthyl derivatives have the potential to be efficacious for the treatment of malaria, but due to higher metabolic clearance than 1, they most likely would need to be part of a multidose regimen. PMID:27127993

  14. Benz[a]anthracene

    Integrated Risk Information System (IRIS)

    Benz [ a ] anthracene ; CASRN 56 - 55 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinoge

  15. Separation of anthracene from crude anthracene using gas antisolvent recrystallization

    SciTech Connect

    Yuchung Liou; Chiehming Chang )

    1992-08-01

    Pure anthracene is mostly used for conversion to anthraquinone, an intermediate for the synthesis of very powerful vat dyestuffs. A coal tar distillate, crude anthracene, which contains 30% anthracene, 25% phenanthrene, 15% carbazole, and other impurities, was used as the model mixture. In this study, 90% by weight purity anthracene was obtained using gas antisolvent (GAS) recrystallization. The GAS process induces the separation of solids by introducing an antisolvent, carbon dioxide (or the supercritical fluid), into acetone which was used as the liquid solvent. The dissolution of the compressed gas into the solute-laden solution selectively lowers the solubilities of solid solutes and salts them out. The results showed that high purity anthracene was obtained at a high feed concentration and high pressure conditions. The separation factor of anthracene versus phenanthrene is close to 30.07.

  16. Synthesis of 9,10-bis-ketoenaminoanthryl and 9,10-bis-isoxazolylanthryl linked biscalix[4]arenes: atropisomers and molecular recognitions.

    PubMed

    Tsai, Chia-Chen; Ho, I-Ting; Chu, Jean-Ho; Shen, Li-Ching; Huang, Shou-Ling; Chung, Wen-Sheng

    2012-03-01

    An efficient synthetic pathway for the synthesis of biscalix[4]arenes 5-10 using 1,3-dipolar cycloaddition reactions is reported. Biscalix[4]arene 10 is capable of forming a complex with methyl viologen because of favorable cation-π interactions and a proper cavity size to accommodate the guest. Moreover, biscalix[4]arenes 8a and 8b were found to be atropisomers at room temperature. These two conformers were unable to exchange at room temperature because of the restricted rotation of the C(9)-C(11) or C(10)-C(12) bonds of the β-amino-α,β-unsaturated ketones of anthracene.

  17. Photoluminescence behavior of europium (III) complexes containing 1-(4-tert-butylphenyl)-3-(2-naphthyl)-propane-1,3-dione ligand.

    PubMed

    Wang, Dunjia; Zheng, Chunyang; Fan, Ling; Hu, Yanjun; Zheng, Jing

    2014-01-01

    Three novel europium complexes with 1-(4-tert-butylphenyl)-3-(2-naphthyl)-propane-1,3-dione (TNPD) and 2,2-dipyridine (Bipy) or 1,10-phenan-throline (Phen) were synthesized and confirmed by FT-IR, (1)H NMR, UV-vis absorption and elemental analysis. Photoluminescence behavior of complexes Eu(TNPD)3, Eu(TNPD)3·Bipy and Eu(TNPD)3·Phen were investigated in detail. Their emission spectra exhibited the characteristic emission bands that arise from the (5)D0→(7)FJ (J=0-4) transitions of the europium ion in solid state. Meanwhile, the results of their lifetime decay curves indicated that only one chemical environment existed around the europium ion. The intrinsic luminescence quantum efficiency (η) and the experimental intensity parameters (Ωt) of europium complexes were determined according to the emission spectra and luminescence decay curves in solid state. The complex Eu(TNPD)3·Phen showed much longer lifetime (τ) and higher luminescence quantum efficiency (η) than complexes Eu(TNPD)3 and Eu(TNPD)3·Bipy.

  18. Evaluation of structure-reactivity descriptors and biological activity spectra of 4-(6-methoxy-2-naphthyl)-2-butanone using spectroscopic techniques

    NASA Astrophysics Data System (ADS)

    Agrawal, Megha; Deval, Vipin; Gupta, Archana; Sangala, Bagvanth Reddy; Prabhu, S. S.

    2016-10-01

    The structure and several spectroscopic features along with reactivity parameters of the compound 4-(6-methoxy-2-naphthyl)-2-butanone (Nabumetone) have been studied using experimental techniques and tools derived from quantum chemical calculations. Structure optimization is followed by force field calculations based on density functional theory (DFT) at the B3LYP/6-311++G(d,p) level of theory. The vibrational spectra have been interpreted with the aid of normal coordinate analysis. UV-visible spectrum and the effect of solvent have been discussed. The electronic properties such as HOMO and LUMO energies have been determined by TD-DFT approach. In order to understand various aspects of pharmacological sciences several new chemical reactivity descriptors - chemical potential, global hardness and electrophilicity have been evaluated. Local reactivity descriptors - Fukui functions and local softnesses have also been calculated to find out the reactive sites within molecule. Aqueous solubility and lipophilicity have been calculated which are crucial for estimating transport properties of organic molecules in drug development. Estimation of biological effects, toxic/side effects has been made on the basis of prediction of activity spectra for substances (PASS) prediction results and their analysis by Pharma Expert software. Using the THz-TDS technique, the frequency-dependent absorptions of NBM have been measured in the frequency range up to 3 THz.

  19. Evaluation of structure-reactivity descriptors and biological activity spectra of 4-(6-methoxy-2-naphthyl)-2-butanone using spectroscopic techniques.

    PubMed

    Agrawal, Megha; Deval, Vipin; Gupta, Archana; Sangala, Bagvanth Reddy; Prabhu, S S

    2016-10-01

    The structure and several spectroscopic features along with reactivity parameters of the compound 4-(6-methoxy-2-naphthyl)-2-butanone (Nabumetone) have been studied using experimental techniques and tools derived from quantum chemical calculations. Structure optimization is followed by force field calculations based on density functional theory (DFT) at the B3LYP/6-311++G(d,p) level of theory. The vibrational spectra have been interpreted with the aid of normal coordinate analysis. UV-visible spectrum and the effect of solvent have been discussed. The electronic properties such as HOMO and LUMO energies have been determined by TD-DFT approach. In order to understand various aspects of pharmacological sciences several new chemical reactivity descriptors - chemical potential, global hardness and electrophilicity have been evaluated. Local reactivity descriptors - Fukui functions and local softnesses have also been calculated to find out the reactive sites within molecule. Aqueous solubility and lipophilicity have been calculated which are crucial for estimating transport properties of organic molecules in drug development. Estimation of biological effects, toxic/side effects has been made on the basis of prediction of activity spectra for substances (PASS) prediction results and their analysis by Pharma Expert software. Using the THz-TDS technique, the frequency-dependent absorptions of NBM have been measured in the frequency range up to 3THz.

  20. Evaluation of structure-reactivity descriptors and biological activity spectra of 4-(6-methoxy-2-naphthyl)-2-butanone using spectroscopic techniques.

    PubMed

    Agrawal, Megha; Deval, Vipin; Gupta, Archana; Sangala, Bagvanth Reddy; Prabhu, S S

    2016-10-01

    The structure and several spectroscopic features along with reactivity parameters of the compound 4-(6-methoxy-2-naphthyl)-2-butanone (Nabumetone) have been studied using experimental techniques and tools derived from quantum chemical calculations. Structure optimization is followed by force field calculations based on density functional theory (DFT) at the B3LYP/6-311++G(d,p) level of theory. The vibrational spectra have been interpreted with the aid of normal coordinate analysis. UV-visible spectrum and the effect of solvent have been discussed. The electronic properties such as HOMO and LUMO energies have been determined by TD-DFT approach. In order to understand various aspects of pharmacological sciences several new chemical reactivity descriptors - chemical potential, global hardness and electrophilicity have been evaluated. Local reactivity descriptors - Fukui functions and local softnesses have also been calculated to find out the reactive sites within molecule. Aqueous solubility and lipophilicity have been calculated which are crucial for estimating transport properties of organic molecules in drug development. Estimation of biological effects, toxic/side effects has been made on the basis of prediction of activity spectra for substances (PASS) prediction results and their analysis by Pharma Expert software. Using the THz-TDS technique, the frequency-dependent absorptions of NBM have been measured in the frequency range up to 3THz. PMID:27284764

  1. Photoluminescence in anthracene and it's derivatives

    NASA Astrophysics Data System (ADS)

    Vyas, Arpita; Mirgane, Nitin A.; Moharil, S. V.; Muley, Aarti Iyer

    2016-05-01

    The anthracene and it's derivative 9-chloro acridine and Anthracene-9-ylmethylacetate have prepared in Poly vinyl alcohol(PVOH). Their photoluminescence properties have studied. The pure anthracene has an emission at 424 and 443nm. The intense peak is observed at 465nm and shoulder at 407nm. The derivatives of anthracene Anthracene-9-ylmethylacetate shows an emission around 440nm for the excitation at 393nm and 9-chloro acridine shows emission around 360nm for the excitation at 290nm. The major problem of this organic material is the stability. The composites prepared in the medium of PVOH are more stable.

  2. Dibenz[a,h]anthracene

    Integrated Risk Information System (IRIS)

    Dibenz [ a , h ] anthracene ; CASRN 53 - 70 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncar

  3. Excellent deep-blue emitting materials based on anthracene derivatives for non-doped organic light-emitting diodes

    NASA Astrophysics Data System (ADS)

    Wang, Zhiqiang; Liu, Wei; Xu, Chen; Ji, Baoming; Zheng, Caijun; Zhang, Xiaohong

    2016-08-01

    Two deep-blue emitting materials 2-tert-butyl-9,10-bis(3,5-diphenylphenyl)anthracene (An-1) and 2-tert-butyl-9,10-bis(3,5-diphenylbiphenyl-4‧-yl)anthracene (An-2) were successfully synthesized by the Pd-catalyzed Suzuki coupling reaction. Both of these compounds have high thermal stabilities and show strong deep-blue emission as solid-state film as well as in n-hexane solution. Two non-doped electroluminescent devices employing An-1 and An-2 as emitting layers were fabricated by vacuum vapor deposition. These devices exhibited highly efficient and stable deep-blue emission with high color purity. The CIE coordinate and maximum EQE of An-1 based device are 4.2% and (0.16, 0.06), respectively. Device based on An-2 achieved a maximum EQE of 4.0% and a CIE coordinate of (0.16, 0.10).

  4. A Dipolar Anthracene Dye: Synthesis, Optical Properties and Two-photon Tissue Imaging.

    PubMed

    Moon, Hyunsoo; Jun, Yong Woong; Kim, Dokyoung; Ryu, Hye Gun; Wang, Taejun; Kim, Ki Hean; Huh, Youngbuhm; Jung, Junyang; Ahn, Kyo Han

    2016-09-20

    Two-photon microscopy is a powerful tool for studying biological systems. In search of novel two-photon absorbing dyes for bioimaging, we synthesized a new anthracene-based dipolar dye (anthradan) and evaluated its two-photon absorbing and imaging properties. The new anthradan, 9,10-bis(o-dimethoxy-phenyl)-anthradan, absorbs and emits at longer wavelengths than acedan, a well-known two-photon absorbing dye. It is also stable under two-photon excitation conditions and biocompatible, and thus used for two-photon imaging of mouse organ tissues to show bright, near-red fluorescence along with negligible autofluorescence. Such an anthradan thus holds promise as a new class of two-photon absorbing dyes for the development of fluorescent probes and tags for biological systems. PMID:27535006

  5. A Dipolar Anthracene Dye: Synthesis, Optical Properties and Two-photon Tissue Imaging.

    PubMed

    Moon, Hyunsoo; Jun, Yong Woong; Kim, Dokyoung; Ryu, Hye Gun; Wang, Taejun; Kim, Ki Hean; Huh, Youngbuhm; Jung, Junyang; Ahn, Kyo Han

    2016-09-20

    Two-photon microscopy is a powerful tool for studying biological systems. In search of novel two-photon absorbing dyes for bioimaging, we synthesized a new anthracene-based dipolar dye (anthradan) and evaluated its two-photon absorbing and imaging properties. The new anthradan, 9,10-bis(o-dimethoxy-phenyl)-anthradan, absorbs and emits at longer wavelengths than acedan, a well-known two-photon absorbing dye. It is also stable under two-photon excitation conditions and biocompatible, and thus used for two-photon imaging of mouse organ tissues to show bright, near-red fluorescence along with negligible autofluorescence. Such an anthradan thus holds promise as a new class of two-photon absorbing dyes for the development of fluorescent probes and tags for biological systems.

  6. 40 CFR 721.715 - Trisubstituted anthracene.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.715 Trisubstituted anthracene. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as trisubstituted anthracene (PMN P-91-689)...

  7. 40 CFR 721.715 - Trisubstituted anthracene.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.715 Trisubstituted anthracene. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as trisubstituted anthracene (PMN P-91-689)...

  8. Spectrophotometric Determination of Cu(2+) and Monitoring of Hg(2+) and Ni(2+) in some Iranian Vegetables Using 6-(2-Naphthyl)-2, 3-Dihydro-as-triazine-3-thione.

    PubMed

    Shamsa, Fazel; Barazande Tehrani, Malehe; Mehravar, Hamid; Mohammadi, Elaheh

    2013-01-01

    Recently, 6-(2-naphthyl)-2, 3-dihydro-as-triazine-3-thione (NDTT) was synthesized in laboratory and used successfully for the spectrophotometric determination of nanogram levels of Cu(2+) in aqueous solution. This reagent forms a specific red complex with Cu(2+) ions after the extraction by chloroform at alkaline pH. The absorption of the complex in the UV region (313 nm) is about 8 times as strong as in the visible one (510 nm). Mercury and nickel ions form yellow complexes with NDTT under the same conditions which interfere in the UV region and without effect on Cu (II) absorbance in the visible region. The studied vegetables include Mentha pipereta L., Anethum graveolens L., Beta vulgaris L., Coriandrum sativum, Petroselinum hortense H., Ocimum basilicum L., Spinacia oleracea L., Lactuca sativa L., and Brassica oleracea L. PMID:24250566

  9. Spectrophotometric Determination of Cu2+ and Monitoring of Hg2+ and Ni2+ in some Iranian Vegetables Using 6-(2-Naphthyl)-2, 3-Dihydro-as-triazine-3-thione

    PubMed Central

    Shamsa, Fazel; Barazande Tehrani, Malehe; Mehravar, Hamid; Mohammadi, Elaheh

    2013-01-01

    Recently, 6-(2-naphthyl)-2, 3-dihydro-as-triazine-3-thione (NDTT) was synthesized in laboratory and used successfully for the spectrophotometric determination of nanogram levels of Cu2+ in aqueous solution. This reagent forms a specific red complex with Cu2+ ions after the extraction by chloroform at alkaline pH. The absorption of the complex in the UV region (313 nm) is about 8 times as strong as in the visible one (510 nm). Mercury and nickel ions form yellow complexes with NDTT under the same conditions which interfere in the UV region and without effect on Cu (II) absorbance in the visible region. The studied vegetables include Mentha pipereta L., Anethum graveolens L., Beta vulgaris L., Coriandrum sativum, Petroselinum hortense H., Ocimum basilicum L., Spinacia oleracea L., Lactuca sativa L., and Brassica oleracea L. PMID:24250566

  10. Photoconductivity of anthracene in liquid hydrocarbons

    SciTech Connect

    Tweeten, D.W.; Lipsky, S. )

    1989-03-23

    The photocurrent from anthracene in 2,2,4-trimethylpentane, 2,2-dimethylbutane, cyclohexane, cyclopentane, and tetramethylsilane has been studied as a function of excitation energy from the ionization threshold to the onset of strong solvent absorption. In the case of 2,2,4-trimethylpentane (isooctane), the dependence of the photocurrent on the magnitude of an externally applied electric field was additionally studied in order to separately evaluate the effect of excitation energy on the electron ejection probability and on the geminate ion pair escape probability. The effect of excitation energy on the quenching by n-perfluorohexane of the anthracene photocurrent in isooctane in also reported.

  11. Photoinduced singlet charge transfer in a ruthenium(II) perylene-3,4:9,10-bis(dicarboximide) complex.

    PubMed

    Gunderson, Victoria L; Krieg, Elisha; Vagnini, Michael T; Iron, Mark A; Rybtchinski, Boris; Wasielewski, Michael R

    2011-06-16

    Elucidation of photoinduced charge transfer behavior in organic dye/metal hybrids is important for developing photocatalytic systems for solar energy conversion. We report the synthesis and photophysical characterization of a perylene-3,4:9,10-bis(dicarboximide) (PDI)-ruthenium(II) complex, bis-PDI-2,2'-bipyridineRu(II)Cl(2)(CN(t)butyl)(2), which has favorable energetics, ΔG(CS) ≈ -1.0 eV, for singlet electron transfer from the Ru complex to PDI. Time-resolved optical spectroscopy reveals that upon selective photoexcitation of PDI, ultrafast charge transfer (<150 fs) from the Ru complex to (1*)PDI generates the Ru(III)-PDI(-•) ion pair. The resulting vibrationally hot Ru(III)-PDI(-•) ion pair exhibits fast relaxation (τ = 3.9 ps) and charge recombination (τ(CR) = 63 ps). Our experimental and computational (DFT and TDDFT) studies show that energy-preserving photodriven singlet electron transfer can dominate in properly designed organic dye/metal complexes, making them of particular interest for use in artificial photosynthetic systems for solar fuels formation. PMID:21598951

  12. Solubility of anthracene and anthraquinone in cyclohexanone + carbon dioxide

    SciTech Connect

    Chang, C.J. . Dept. of Chemical Engineering)

    1994-10-01

    In the processing of an anthracene oil fraction from coal tar, a mixture of anthracene and anthraquinone is required to be separated to obtain products of high purity. The solubilities of anthracene and anthraquinone were measured in cyclohexanone + carbon dioxide as a function of the temperature and pressure of carbon dioxide at 291, 300, and 313 K and from 1.8--12.4 MPa. Average equilibrium solubilities and recoveries of both solids increased with increasing normalized concentration and pressure. The average separation factor of anthracene to anthraquinone, due to the effect of the mixed solvent, was 2.88 [+-] 1.91.

  13. Identification of toxic products of anthracene photomodification in simulated sunlight.

    PubMed

    Brack, Werner; Altenburger, Rolf; Küster, Eberhard; Meissner, Bettina; Wenzel, Klaus-Dieter; Schüürmann, Gerrit

    2003-10-01

    Currently, the evidence of a rapid photomodification of anthracene under sunlight resulting in enhanced toxicity exists; however, the chemical causes of toxicity are still unknown. The present study aimed at filling this gap by irradiation of an anthracene suspension with simulated sunlight and subsequent effect-directed fractionation and analysis of toxic products with respect to the inhibition of bacterial energy metabolism of Vibrio fischeri, reproduction of the green algae Scenedesmus vacuolatus, and genotoxicity in the umuC test. Algal toxicity of anthracene was hardly modified by irradiation prior to testing and distributed over all fractions with emphasis on the fractions containing anthracene-9,10-dione and a photometabolite suggested to be 10-hydroxyanthrone. Bacterial toxicity and genotoxicity in contrast emerged only when anthracene was irradiated. Anthracene-1,4-dione, a so-far-unknown trace photometabolite, was identified as a very potent toxicant dominating the toxicity of photomodified anthracene to V. fischeri. In genotoxic fractions, 1-hydroxyanthracene-9,10-dione and 1,4-dihydroxyanthracene-9,10-dione were identified and confirmed as genotoxicants. The results stress the potential of effect-directed analysis approaches in contrast to mere chemical analysis in studies aiming at toxicologically relevant photomodified substances.

  14. Thermochemical and Vapor Pressure Behavior of Anthracene and Brominated Anthracene Mixtures.

    PubMed

    Fu, Jinxia; Suuberg, Eric M

    2013-03-25

    The present work concerns the thermochemical and vapor pressure behavior of the anthracene (1) + 2-bromoanthracene (2) and anthracene (1) + 9-bromoanthracene (3) systems. Solid-liquid equilibrium temperature and differential scanning calorimetry studies indicate the existence of a minimum melting solid state near an equilibrium temperature of 477.65 K at x 1 = 0.74 for the (1) + (2) system. Additionally, solid-vapor equilibrium studies for the (1) + (2) system show that the vapor pressure of the mixtures depends on composition, but does not follow ideal Raoult's law behaviour. The (1) + (3) system behaves differently from the (1) + (2) system. The (1) + (3) system has a solid solution like phase diagram. The system consists of two phases, an anthracene like phase and a 9-bromoanthracene like phase, while (1) + (2) mixtures only form a single phase. Moreover, experimental studies of the two systems suggest that the (1) + (2) system is in a thermodynamically lower energy state than the (1) + (3) system. PMID:24319314

  15. Thermochemical and Vapor Pressure Behavior of Anthracene and Brominated Anthracene Mixtures.

    PubMed

    Fu, Jinxia; Suuberg, Eric M

    2013-03-25

    The present work concerns the thermochemical and vapor pressure behavior of the anthracene (1) + 2-bromoanthracene (2) and anthracene (1) + 9-bromoanthracene (3) systems. Solid-liquid equilibrium temperature and differential scanning calorimetry studies indicate the existence of a minimum melting solid state near an equilibrium temperature of 477.65 K at x1 = 0.74 for the (1) + (2) system. Additionally, solid-vapor equilibrium studies for the (1) + (2) system show that the vapor pressure of the mixtures depends on composition, but does not follow ideal Raoult's law behaviour. The (1) + (3) system behaves differently from the (1) + (2) system. The (1) + (3) system has a solid solution like phase diagram. The system consists of two phases, an anthracene like phase and a 9-bromoanthracene like phase, while (1) + (2) mixtures only form a single phase. Moreover, experimental studies of the two systems suggest that the (1) + (2) system is in a thermodynamically lower energy state than the (1) + (3) system.

  16. Fate of anthracene in an artificial stream: a case study

    SciTech Connect

    Landrum, P.F.; Bartell, S.M.; Giesy, J.P.; Leversee, G.J.; Bowling, J.W.; Haddock, J.; LaGory, K.; Gerould, S.; Bruno, M.

    1984-04-01

    The fate of anthracene, a representative polycyclic aromatic hydrocarbon, was followed in a large outdoor stream microcosm. The major nonadvective route for the removal of anthracene was photolytic degradation to anthraquinone (half-life 43 min). The anthraquinone also photolyzed rapidly in this shallow stream system. Excluding the plastic channel liner, the sediment acts as the major sink for anthracene, absorbing 0.2% of the 14-day input dose. The periphyton community was the second most important sink, absorbing 0.04% of the input dose. All other compartments were of significantly less importance on a mass basis. Anthracene (11 micrograms liter-1) caused photo-induced 100% mortality of the bluegill sunfish in 9 hr in the upstream reach. Fish at the downstream station survived for approximately 26 hr and all died within 1 hr of each other. Other organisms, clams and dragonfly larvae, started to die off toward the end of the 14-day input period.

  17. Anthracene + Pyrene Solid Mixtures: Eutectic and Azeotropic Character

    PubMed Central

    Rice, James W.; Fu, Jinxia; Suuberg, Eric M.

    2010-01-01

    To better characterize the thermodynamic behavior of a binary polycyclic aromatic hydrocarbon mixture, thermochemical and vapor pressure experiments were used to examine the phase behavior of the anthracene (1) + pyrene (2) system. A solid-liquid phase diagram was mapped for the mixture. A eutectic point occurs at 404 K at x1 = 0.22. A model based on eutectic formation can be used to predict the enthalpy of fusion associated with the mixture. For mixtures that contain x1 < 0.90, the enthalpy of fusion is near that of pure pyrene. This and X-ray diffraction results indicate that mixtures of anthracene and pyrene have pyrene-like crystal structures and energetics until the composition nears that of pure anthracene. Solid-vapor equilibrium studies show that mixtures of anthracene and pyrene form solid azeotropes at x1 of 0.03 and 0.14. Additionally, mixtures at x1 = 0.99 sublime at the vapor pressure of pure anthracene, suggesting that anthracene behavior is not significantly influenced by x2 = 0.01 in the crystal structure. PMID:21116474

  18. Fungal biodegradation of anthracene-polluted cork: A comparative study.

    PubMed

    Jové, Patrícia; Olivella, Maria À; Camarero, Susana; Caixach, Josep; Planas, Carles; Cano, Laura; De Las Heras, Francesc X

    2016-01-01

    The efficiency of cork waste in adsorbing aqueous polycyclic aromatic hydrocarbons (PAHs) has been previously reported. Biodegradation of contaminated cork using filamentous fungi could be a good alternative for detoxifying cork to facilitate its final processing. For this purpose, the degradation efficiency of anthracene by three ligninolytic white-rot fungi (Phanerochaete chrysosporium, Irpex lacteus and Pleurotus ostreatus) and three non-ligninolytic fungi which are found in the cork itself (Aspergillus niger, Penicillium simplicissimum and Mucor racemosus) are compared. Anthracene degradation by all fungi was examined in solid-phase cultures after 0, 16, 30 and 61 days. The degradation products of anthracene by P. simplicissimum and I. lacteus were also identified by GC-MS and a metabolic pathway was proposed for P. simplicissimum. Results show that all the fungi tested degraded anthracene. After 61 days of incubation, approximately 86%, 40%, and 38% of the initial concentration of anthracene (i.e., 100 µM) was degraded by P. simplicissimum, P. chrysosporium and I. lacteus, respectively. The rest of the fungi degraded anthracene to a lesser extent (<30%). As a final remark, the results obtained in this study indicate that P. simplicissimum, a non-ligninolytic fungi characteristic of cork itself, could be used as an efficient degrader of PAH-contaminated cork. PMID:26540209

  19. Anthracene + Pyrene Solid Mixtures: Eutectic and Azeotropic Character.

    PubMed

    Rice, James W; Fu, Jinxia; Suuberg, Eric M

    2010-09-01

    To better characterize the thermodynamic behavior of a binary polycyclic aromatic hydrocarbon mixture, thermochemical and vapor pressure experiments were used to examine the phase behavior of the anthracene (1) + pyrene (2) system. A solid-liquid phase diagram was mapped for the mixture. A eutectic point occurs at 404 K at x(1) = 0.22. A model based on eutectic formation can be used to predict the enthalpy of fusion associated with the mixture. For mixtures that contain x(1) < 0.90, the enthalpy of fusion is near that of pure pyrene. This and X-ray diffraction results indicate that mixtures of anthracene and pyrene have pyrene-like crystal structures and energetics until the composition nears that of pure anthracene. Solid-vapor equilibrium studies show that mixtures of anthracene and pyrene form solid azeotropes at x(1) of 0.03 and 0.14. Additionally, mixtures at x(1) = 0.99 sublime at the vapor pressure of pure anthracene, suggesting that anthracene behavior is not significantly influenced by x(2) = 0.01 in the crystal structure.

  20. Fungal biodegradation of anthracene-polluted cork: A comparative study.

    PubMed

    Jové, Patrícia; Olivella, Maria À; Camarero, Susana; Caixach, Josep; Planas, Carles; Cano, Laura; De Las Heras, Francesc X

    2016-01-01

    The efficiency of cork waste in adsorbing aqueous polycyclic aromatic hydrocarbons (PAHs) has been previously reported. Biodegradation of contaminated cork using filamentous fungi could be a good alternative for detoxifying cork to facilitate its final processing. For this purpose, the degradation efficiency of anthracene by three ligninolytic white-rot fungi (Phanerochaete chrysosporium, Irpex lacteus and Pleurotus ostreatus) and three non-ligninolytic fungi which are found in the cork itself (Aspergillus niger, Penicillium simplicissimum and Mucor racemosus) are compared. Anthracene degradation by all fungi was examined in solid-phase cultures after 0, 16, 30 and 61 days. The degradation products of anthracene by P. simplicissimum and I. lacteus were also identified by GC-MS and a metabolic pathway was proposed for P. simplicissimum. Results show that all the fungi tested degraded anthracene. After 61 days of incubation, approximately 86%, 40%, and 38% of the initial concentration of anthracene (i.e., 100 µM) was degraded by P. simplicissimum, P. chrysosporium and I. lacteus, respectively. The rest of the fungi degraded anthracene to a lesser extent (<30%). As a final remark, the results obtained in this study indicate that P. simplicissimum, a non-ligninolytic fungi characteristic of cork itself, could be used as an efficient degrader of PAH-contaminated cork.

  1. Transformation of anthracene on various cation-modified clay minerals.

    PubMed

    Li, Li; Jia, Hanzhong; Li, Xiyou; Wang, Chuanyi

    2015-01-01

    In this study, anthracene was employed as a probe to explore the potential catalytic effect of clay minerals in soil environment. Clay minerals saturated with various exchangeable cations were tested. The rate of anthracene transformation follows the order: Fe-smectite > Cu-smectite > Al-smectite ≈ Ca-smectite ≈ Mg-smectite ≈ Na-smectite. This suggests that transition-metal ions such as Fe(III) play an important role in anthracene transformation. Among Fe(III)-saturated clays, Fe(III)-smectite exhibits the highest catalytic activity followed by Fe(III)-illite, Fe(III)-pyrophyllite, and Fe(III)-kaolinite, which is in agreement with the interlayer Fe(III) content. Moreover, effects by two common environmental factors, pH and relative humidity (RH), were evaluated. With an increase in pH or RH, the rate of anthracene transformation decreases rapidly at first and then is leveled off. GC-MS analysis identifies that the final product of anthracene transformation is 9,10-anthraquinone, a more bioavailable molecule compared to anthracene. The transformation process mainly involves cation-π bonding, electron transfer leading to cation radical, and further oxidation by chemisorbed O2. The present work provides valuable insights into the abiotic transformation and the fate of PAHs in the soil environment and the development of contaminated land remediation technologies.

  2. Blue Fluorescent Materials Composed of Anthracene-Aryl Amine-Anthracene Derivatives for Organic Light-Emitting Diodes.

    PubMed

    Lee, Seul Bee; Song, Ji Young; Yang, Hyung Jin; Kim, Young Kwan; Yoon, Seung Soo

    2015-07-01

    Blue fluorescent emitters based on anthracene-aryl amine-anthracene derivatives were studied for efficient OLEDs. Compound 1 exhibited efficient EL propereties with luminous and power efficien- cies of 4.50 cd/A and 1.75 lm/W at 200 mA/cm2, respectively and CIE coordinates of (0.18, 0.26) at 7.0 V.

  3. Ring fission of anthracene by a eukaryote.

    PubMed Central

    Hammel, K E; Green, B; Gai, W Z

    1991-01-01

    Ligninolytic fungi are unique among eukaryotes in their ability to degrade polycyclic aromatic hydrocarbons (PAHs), but the mechanism for this process is unknown. Although certain PAHs are oxidized in vitro by the fungal lignin peroxidases (LiPs) that catalyze ligninolysis, it has never been shown that LiPs initiate PAH degradation in vivo. To address these problems, the metabolism of anthracene (AC) and its in vitro oxidation product, 9,10-anthraquinone (AQ), was examined by chromatographic and isotope dilution techniques in Phanerochaete chrysosporium. The fungal oxidation of AC to AQ was rapid, and both AC and AQ were significantly mineralized. Both compounds were cleaved by the fungus to give the same ring-fission metabolite, phthalic acid, and phthalate production from AQ was shown to occur only under ligninolytic culture conditions. These results show that the major pathway for AC degradation in Phanerochaete proceeds AC----AQ----phthalate + CO2 and that it is probably mediated by LiPs and other enzymes of ligninolytic metabolism. Images PMID:1961727

  4. Characterization and pyrolysis behavior of novel anthracene oil derivatives

    SciTech Connect

    P. Alvarez; M. Granda; J. Sutil; R. Menendez; J.J. Fernandez; J.A. Vina; T.J. Morgan; M. Millan; A.A. Herod; R. Kandiyoti

    2008-11-15

    The characterization and pyrolysis behavior of a set of pitches prepared from anthracene oil have been described. The pitches were obtained from four successive cycles of a sequential process that begins with blowing air through the heated anthracene oil, to bring about recombination reactions. Reaction products are distilled to give a pitch residue and a lighter fraction. Thermal treatment/distillation cycles of this reaction product yield a pitch and a distillate fraction (unreacted anthracene oil) during each subsequent stage. Products obtained during the process have been characterized by elemental analysis, Fourier transform infrared (FTIR) and ultraviolet (UV)-fluorescence spectroscopy, and size-exclusion chromatography (SEC). The pyrolytic behavior of the anthracene oil derivatives was examined using a thermogravimetric balance. Thermal treatment of the anthracene oil and its (distilled) reaction products at 440-460{degree}C under 5 bar pressure leads to a partially anisotropic pitch with the formation of a liquid crystal phase (mesophase). The formation and evolution of these mesophases were analyzed by optical microscopy. 25 refs., 9 figs., 3 tabs.

  5. Thermodynamic study of (anthracene + phenanthrene) solid state mixtures

    PubMed Central

    Rice, James W.; Fu, Jinxia; Sandström, Emma; Ditto, Jenna C.; Suuberg, Eric M.

    2015-01-01

    Polycyclic aromatic hydrocarbons (PAH) are common components of many materials, such as petroleum and various types of tars. They are generally present in mixtures, occurring both naturally and as byproducts of fuel processing operations. It is important to understand the thermodynamic properties of such mixtures in order to understand better and predict their behavior (i.e., fate and transport) in the environment and in industrial operations. To characterize better the thermodynamic behavior of PAH mixtures, the phase behavior of a binary (anthracene + phenanthrene) system was studied by differential scanning calorimetry, X-ray diffraction, and the Knudsen effusion technique. Mixtures of (anthracene + phenanthrene) exhibit non-ideal mixture behavior. They form a lower-melting, phenanthrene-rich phase with an initial melting temperature of 372 K (identical to the melting temperature of pure phenanthrene) and a vapor pressure of roughly lnP/Pa = −2.38. The phenanthrene-rich phase coexists with an anthracene-rich phase when the mole fraction of phenanthrene (xP) in the mixture is less than or equal to 0.80. Mixtures initially at xP = 0.90 consist entirely of the phenanthrene-rich phase and sublime at nearly constant vapor pressure and composition, consistent with azeotrope-like behavior. Quasi-azeotropy was also observed for very high-content anthracene mixtures (2.5 < xP < 5) indicating that anthracene may accommodate very low levels of phenanthrene in its crystal structure. PMID:26973354

  6. Stereoselective fungal metabolism of methylated anthracenes.

    PubMed Central

    Cerniglia, C E; Campbell, W L; Fu, P P; Freeman, J P; Evans, F E

    1990-01-01

    The metabolism of 9-methylanthracene (9-MA), 9-hydroxymethylanthracene (9-OHMA), and 9,10-dimethylanthracene (9,10-DMA) by the fungus Cunninghamella elegans ATCC 36112 is described. The metabolites were isolated by high-performance liquid chromatography and characterized by UV-visible, mass, and 1H nuclear magnetic resonance spectral techniques. The compounds 9-MA and 9,10-DMA were metabolized by two pathways, one involving initial hydroxylation of the methyl group(s) and the other involving epoxidation of the 1,2- and 3,4- aromatic double bond positions, followed by enzymatic hydration to form hydroxymethyl trans-dihydrodiols. For 9-MA metabolism, the major metabolites identified were trans-1,2-dihydro-1,2-dihydroxy and trans-3,4-dihydro-3,4-dihydroxy derivatives of 9-MA and 9-OHMA. 9-OHMA was also metabolized to trans-1,2- and 3,4-dihydrodiol derivatives. The absolute configuration and optical purity were determined for each of the trans-dihydrodiols formed by fungal metabolism and compared with previously published circular dichroism spectral data obtained from rat liver microsomal metabolism of 9-MA, 9-OHMA, and 9,10-DMA. Circular dichroism spectral analysis revealed that the major enantiomer for each dihydrodiol was predominantly in the S,S configuration, in contrast to the predominantly R,R configuration of the trans-dihydrodiol formed by mammalian enzyme systems. These results indicate that C. elegans metabolizes methylated anthracenes in a highly stereoselective manner that is different from that reported for rat liver microsomes. PMID:2317041

  7. Thermodynamic study of (anthracene + benzo[a]pyrene) solid mixtures.

    PubMed

    Rice, James W; Suuberg, Eric M

    2010-11-01

    To characterize better the thermodynamic behavior of a binary polycyclic aromatic hydrocarbon mixture, thermochemical and vapor pressure experiments were used to examine the phase behavior of the {anthracene (1) + benzo[a]pyrene (2)} system. A solid-liquid phase diagram was mapped for the mixture. A eutectic point occurs at x(1) = 0.26. The eutectic mixture is an amorphous solid that lacks organized crystal structure and melts between T = (414 and 420) K. For mixtures that contain 0.10 < x(1) < 0.90, the enthalpy of fusion is dominated by that of the eutectic. Solid-vapor equilibrium studies show that mixtures of anthracene and benzo[a]pyrene at x(1) < 0.10 sublime at the vapor pressure of pure benzo[a]pyrene. These results suggest that the solid-vapor equilibrium of benzo[a]pyrene is not significantly influenced by moderate levels of anthracene in the crystal structure.

  8. Thermodynamic study of (anthracene + benzo[a]pyrene) solid mixtures

    PubMed Central

    Rice, James W.; Suuberg, Eric M.

    2010-01-01

    To characterize better the thermodynamic behavior of a binary polycyclic aromatic hydrocarbon mixture, thermochemical and vapor pressure experiments were used to examine the phase behavior of the {anthracene (1) + benzo[a]pyrene (2)} system. A solid-liquid phase diagram was mapped for the mixture. A eutectic point occurs at x1 = 0.26. The eutectic mixture is an amorphous solid that lacks organized crystal structure and melts between T = (414 and 420) K. For mixtures that contain 0.10 < x1 < 0.90, the enthalpy of fusion is dominated by that of the eutectic. Solid-vapor equilibrium studies show that mixtures of anthracene and benzo[a]pyrene at x1 < 0.10 sublime at the vapor pressure of pure benzo[a]pyrene. These results suggest that the solid-vapor equilibrium of benzo[a]pyrene is not significantly influenced by moderate levels of anthracene in the crystal structure. PMID:20814451

  9. Toxic photoproducts of phenanthrene and anthracene in sunlight

    SciTech Connect

    Duxbury, C.L.; McConkey, B.J.; Mallakin, A.; Dixon, D.G.; Greenberg, B.M.

    1995-12-31

    Phenanthrene and anthracene, two of the most prevalent PAHs, undergo significant increases in toxicity on exposure to sunlight. Over a period of several days exposure to light, the toxicity of an aqueous solution of phenanthrene or anthracene increased dramatically. This increase in toxicity is largely due to the primary products formed by these two PAHs due to light exposure. These compounds are more toxic than the parent compounds at equimolar concentrations. Although anthracene is a potent photosensitizer, phenanthrene did not exhibit a significant increase in toxicity due to photosensitization. Photo-oxidation was the principal cause of photoinduced toxicity, with 9,10-phenanthrenequinone being the primary product. This compound is more water soluble than phenanthrene increasing its bioavailability. In addition, mixtures of phenanthrene and 9,10-phenanthrenequinone exhibited toxicity similar to the quinone added alone. This was shown by joint toxicity testing using Lemna gibba and Daphnia magna. These two organisms are currently being used in the lab to further test individual oxidized products of anthracene and phenanthrene that occur as a result of exposure to sunlight.

  10. Anthracene Clusters and the Interstellar Infrared Emission Features

    NASA Astrophysics Data System (ADS)

    Roser, J. E.; Ricca, A.; Allamandola, L. J.

    2014-03-01

    The unidentified infrared bands are ubiquitous in the interstellar medium and typically attributed to emission from neutral and ionized polycyclic aromatic hydrocarbons (or PAHs). The contribution of neutral PAH clusters to these bands has been impossible to determine due to a paucity of infrared spectral data. Here we investigated neutral clusters of the three-ring PAH anthracene using FTIR absorption spectroscopy of anthracene matrix-isolated at varying concentrations in solid argon. In order to determine likely cluster structures of the embedded molecules, we also calculated theoretical absorption spectra for the anthracene monomer through hexamer using density functional theory with a dispersion correction (DFT-D). The DFT-D calculations have been calibrated for the anthracene dimer using the second-order Møller-Plesset approach. Because there is some support for the hypothesis that three or four-ring PAHs are present in the Red Rectangle nebula, we discuss the application of our results to this nebula in particular as well as to the interstellar infrared emission in general.

  11. Anthracene clusters and the interstellar infrared emission features

    SciTech Connect

    Roser, J. E.; Ricca, A.; Allamandola, L. J.

    2014-03-10

    The unidentified infrared bands are ubiquitous in the interstellar medium and typically attributed to emission from neutral and ionized polycyclic aromatic hydrocarbons (or PAHs). The contribution of neutral PAH clusters to these bands has been impossible to determine due to a paucity of infrared spectral data. Here we investigated neutral clusters of the three-ring PAH anthracene using FTIR absorption spectroscopy of anthracene matrix-isolated at varying concentrations in solid argon. In order to determine likely cluster structures of the embedded molecules, we also calculated theoretical absorption spectra for the anthracene monomer through hexamer using density functional theory with a dispersion correction (DFT-D). The DFT-D calculations have been calibrated for the anthracene dimer using the second-order Møller-Plesset approach. Because there is some support for the hypothesis that three or four-ring PAHs are present in the Red Rectangle nebula, we discuss the application of our results to this nebula in particular as well as to the interstellar infrared emission in general.

  12. Stable isotope probing identifies anthracene degraders under methanogenic conditions.

    PubMed

    Zhang, Shuying; Wang, Qingfeng; Xie, Shuguang

    2012-04-01

    Polycyclic aromatic hydrocarbons (PAHs) are common contaminants in groundwater. The remediation of PAH-contaminated groundwater often involves anaerobic biodegradation. The knowledge about the microorganisms responsible for PAH degradation in anaerobic subsurface environment is still lacking. DNA-based stable isotope probing (SIP) was applied to discover the microorganisms responsible for anaerobic anthracene degradation within microcosms inoculated with aquifer sediment from landfill leachate-contaminated site. Three phylotypes were identified as the degraders, all falling within the phylum Proteobacteria. Two anthracene degraders were classified within the genera Methylibium and Legionella, while another one was an unclassified Rhizobiales species. They all were first linked to PAH degradation. These findings also provide an illustration of the utility of SIP to discover the roles of uncultured microorganisms in PAH-degrading processes.

  13. Plasmid-mediated mineralization of naphthalene, phenanthrene, and anthracene.

    PubMed Central

    Sanseverino, J; Applegate, B M; King, J M; Sayler, G S

    1993-01-01

    The well-characterized plasmid-encoded naphthalene degradation pathway in Pseudomonas putida PpG7(NAH7) was used to investigate the role of the NAH plasmid-encoded pathway in mineralizing phenanthrene and anthracene. Three Pseudomonas strains, designated 5R, DFC49, and DFC50, were recovered from a polynuclear aromatic hydrocarbon-degrading inoculum developed from a manufactured gas plant soil slurry reactor. Plasmids pKA1, pKA2, and pKA3, approximately 100 kb in size, were isolated from these strains and characterized. These plasmids have homologous regions of upper and lower NAH7 plasmid catabolic genes. By conjugation experiments, these plasmids, including NAH7, have been shown to encode the genotype for mineralization of [9-14C]phenanthrene and [U-14C]anthracene, as well as [1-14C]naphthalene. One strain, Pseudomonas fluorescens 5RL, which has the complete lower pathway inactivated by transposon insertion in nahG, accumulated a metabolite from phenanthrene and anthracene degradation. This is the first direct evidence to indicate that the NAH plasmid-encoded catabolic genes are involved in degradation of polynuclear aromatic hydrocarbons other than naphthalene. Images PMID:8328809

  14. Mouse skin tumor-initiating activity of 5-, 7-, and 12-methyl- and fluorine-substituted benz(a)anthracenes

    SciTech Connect

    Wood, A.W.; Levin, W.; Chang, R.L.; Conney, A.H.; Slaga, T.J.; O'Malley, R.F.; Newman, M.S.; Buhler, D.R.; Jerina, D.M.

    1982-09-01

    Eleven methyl- and/or fluorine-substitued benz(a)anthracenes were evaluated for tumor-initating activity on mouse skin. Outbred CD-1 and outbred Sencar mice received a single topical application of the hydrocarbons followed by twice weekly application of the tumor promoter 12-O-tetradecanoylphorbol 13-acetate for 16-26 weeks. 7, 12-DMBA was almost two orders of magnitude more active as a tumor-initator than 7- and 12-methylbenz(a)anthracene. Methyl substitution at the 7- and 7,12-positions of benz(a)anthracence was significantly more effective in the enhancement of tumorigenic activity than fluorine substitution at these positions. Although 7-fluorobenz(a)anthracene, 12-fluorobenz(a)anthracene, and 7,12-difluorobenz(a)anthracene had only 0.15, 0.26, and less than 0.005 times the tumor-initiating activity of their respective methyl-substituted derivatives, they were severalfold more active than benz(a)anthracene. 7-Fluorobenz(a)anthracene was slightly less active than 12-fluorobenz(a)anthracene, whereas 7-methylbenz(a)anthracene was about twofold more active than 12-methylbenz(a)anthracene. For 7,12-disubstituted benz(a)anthracenes, 7-methyl-12-fluorobenz(a)anthracene was more than twice as tumorigenic as 7-fluoro-12-methylbenz(a)anthracene, but each was individually more active than 7-methylbenz(a)anthracene and 12-methylbenz(a)anthracene, respectively. Both fluorinated compounds were much less active than 7,12-DMBA. Substitution of fluorine or methyl at the 5-position of 7-methylbenz(a)anthracene and substition of fluorine at the 5-position of 12-methylbenz(a)anthracene dramatically reduced their tumorigenic activity.

  15. Ultrafine Particulate Ferrous Iron and Anthracene Associations with Mitochondrial Dysfunction

    SciTech Connect

    Faiola, Celia; Johansen, Anne M.; Rybka, Sara; Nieber, Annika; Thomas-Bradley, Carin; Bryner, Stephanie; Johnston, Justin M.; Engelhard, Mark H.; Nachimuthu, Ponnusamy; Owens, Kalyn S.

    2011-04-20

    The ultrafine size fraction of ambient particles (ultrafine particles, UFP, diameter < 100 nm) has been identified as being far more potent in their adverse health effects than their larger counterparts, yet, the detailed mechanisms for why UFP display such distinctive toxicity are not well understood. In the present study, ambient UFP were exposed to mitochondria while monitoring electron transport chain (ETC) activity as a model system for biochemical toxicity. UFP samples were collected in rural (Ellensburg, WA) and urban environments (Seattle, WA) and chemically characterized for total trace metals, ferrous (Fe(II)) and easily reducible ferric (Fe(III)) iron, polycyclic aromatic hydrocarbons, and surface constituents with X-ray photoelectron spectroscopy (XPS). Low doses of UFP (8 µg mL-1) caused a decrease in mitochondrial ETC function compared to controls in 94% of the samples after The 20 min of exposure. Significant correlations exist between initial %ETC inhibition (0-10 min) and Fe(II) (R=0.55, P=0.03, N=15), anthracene (R=0.74, P<0.01, N=13), and %C-O surface bonds (R=0.56, P=0.03, N=15), whereby anthracene and %C-O correlate as well (R=0.58, P=0.03, N=14). No significant associations were identified with total Fe and other trace metals. Results from this study indicate that the redox active fraction of Fe as well as the abundance of anthracene-related, C-O containing, surface structures may contribute to the initial detrimental behavior of UFP, thus supporting the idea that the Fe(II)/Fe(III) and certain efficient hydroquinone/quinone redox pairs may play an important role likely due to their potential to produce reactive oxygen species (ROS).

  16. A novel sonication route to prepare anthracene nanoparticles

    SciTech Connect

    Kang Peng; Chen Chunnian; Hao Lingyun; Zhu Chunling; Hu Yuan; Chen Zuyao

    2004-04-02

    A novel sonication method has been successfully developed for the preparation of anthracene nanoparticles. The as-prepared nanoparticles are characterized using transmission electron microscopy, ultraviolet-visible absorption spectroscopy, fluorescence excitation and emission spectroscopy. Nanoparticles prepared with sonication are smaller and better dispersed than with magnetic stirring. Surfactants cetyltrimethylammonium bromide, bis(2-ethylhexyl)sodium sulfosuccinate, sodium dodecyl sulfonate and polyvinylpyrrolidone are used to control the size and morphology. Excimer band is found at 445 and 472 nm and possible mechanism is discussed.

  17. Measurement of the Mean Inner Potentials of Anthracene and Naphthalene

    NASA Astrophysics Data System (ADS)

    Lunt, Richard R.; Kéna-Cohen, Stéphane; Benziger, Jay B.; Forrest, Stephen R.

    2009-02-01

    The mean inner potential in metals, insulators, and semiconductors provides fundamental information regarding the electronic structure of the material. Here, we measure the mean inner potentials of the two archetype linear polyacenes: anthracence and naphthalene. We determine the mean inner potentials of single crystalline anthracene of 5.9 V (±0.3V), and naphthalene of 5.4 V (±0.3V) based on analysis of Kikuchi patterns observed using high-pressure reflection high energy electron diffraction. We show that the inner potential of a range of organic molecular semiconductors can be estimated from their diamagnetic susceptibilities.

  18. Peculiarities of metabolism of anthracene and pyrene by laccase-producing fungus Pycnoporus sanguineus H1.

    PubMed

    Li, Xuanzhen; Wang, Yan; Wu, Shijin; Qiu, Lequan; Gu, Li; Li, Jingjing; Zhang, Bao; Zhong, Weihong

    2014-01-01

    The metabolic peculiarities of anthracene and pyrene by Pycnoporus sanguineus H1 were investigated. The fungus H1 could grow on potato dextrose agar plates with anthracene and anthraquinone as carbon sources. In liquid medium, the strain degraded 8.5% of anthracene as the sole carbon source, with no ligninolytic enzymes detected, indicating that intracellular catabolic enzymes might be responsible for the initial oxidation of anthracene. When bran was added to the medium, the degradation rate of anthracene and pyrene increased to 71.3% and 30.2%, respectively, and the laccase activities increased to a maximal value of 501.2 and 587.6 U/L, respectively. By gas chromatography-mass spectrometry analysis, anthraquinone was detected as the unique intermediate product of anthracene oxidation, with a yield molar ratio of 0.3. In vitro experiments showed that the extracellular culture fluid containing laccase transformed anthracene to anthraquinone with a yield molar ratio of 1.0, which was less than that of the in vivo experiment, indicating that anthraquinone could be further metabolized by the strain. Pyrene could not be oxidized by culture fluid. These results showed that both extracellular laccase and intracellular catabolic enzymes might play an important role in the initial oxidation of anthracene, whereas pyrene could be only oxidized by intracellular catabolic enzymes through cometabolism.

  19. Interaction of higher plant (jute), electrofused bacteria and mycorrhiza on anthracene biodegradation.

    PubMed

    Cheung, K C; Zhang, J Y; Deng, H H; Ou, Y K; Leung, H M; Wu, S C; Wong, M H

    2008-05-01

    The interaction of bacteria, mycorrhiza and jute (Corchotus capsulari, a higher plant) to reduce anthracene in different concentrations of spiked soils was investigated. Dominant indigenous bacterium (Pseudomonas sp.) isolated in the rhizosphere of jute was electrofused with anthracene degraders (Sphingomonas paucimobilis and Pseudomonas aeruginosa) which were able to produce different types of biosurfactants. The highest population (56 x 10(5)CFU/g) was found in the planted soil with the inoculation of mixtures of electrofused anthracene degraders after 7 days. The growth of anthracene degraders in the spiked soil was improved by gene transfer from indigenous bacteria. After 35 days, enhanced anthracene removals were observed in inoculated soils planted with jute (65.5-75.2%) compared with unplanted soil without inoculation (12.5%). The interaction of jute and electrofused S. paucimobilis enabled the greatest reduction of soil anthracene with or without the addition of P. aeruginosa. Mycorrhizal colonization was not significantly inhibited by anthracene in soils up to 150 mg/kg. Inoculation of jute with Glomus mosseae and Glomus intraradices improved plant growth and enhanced anthracene removal in the presence of electrofused S. paucimobilis.

  20. Direct modulation of microtubule stability contributes to anthracene general anesthesia.

    PubMed

    Emerson, Daniel J; Weiser, Brian P; Psonis, John; Liao, Zhengzheng; Taratula, Olena; Fiamengo, Ashley; Wang, Xiaozhao; Sugasawa, Keizo; Smith, Amos B; Eckenhoff, Roderic G; Dmochowski, Ivan J

    2013-04-10

    Recently, we identified 1-aminoanthracene as a fluorescent general anesthetic. To investigate the mechanism of action, a photoactive analogue, 1-azidoanthracene, was synthesized. Administration of 1-azidoanthracene to albino stage 40-47 tadpoles was found to immobilize animals upon near-UV irradiation of the forebrain region. The immobilization was often reversible, but it was characterized by a longer duration consistent with covalent attachment of the ligand to functionally important targets. IEF/SDS-PAGE examination of irradiated tadpole brain homogenate revealed labeled protein, identified by mass spectrometry as β-tubulin. In vitro assays with aminoanthracene-cross-linked tubulin indicated inhibition of microtubule polymerization, similar to colchicine. Tandem mass spectrometry confirmed anthracene binding near the colchicine site. Stage 40-47 tadpoles were also incubated 1 h with microtubule stabilizing agents, epothilone D or discodermolide, followed by dosing with 1-aminoanthracene. The effective concentration of 1-aminoanthracene required to immobilize the tadpoles was significantly increased in the presence of either microtubule stabilizing agent. Epothilone D similarly mitigated the effects of a clinical neurosteroid general anesthetic, allopregnanolone, believed to occupy the colchicine site in tubulin. We conclude that neuronal microtubules are "on-pathway" targets for anthracene general anesthetics and may also represent functional targets for some neurosteroid general anesthetics. PMID:23484901

  1. Direct Modulation of Microtubule Stability Contributes to Anthracene General Anesthesia

    PubMed Central

    Emerson, Daniel J.; Weiser, Brian P.; Psonis, John; Liao, Zhengzheng; Taratula, Olena; Fiamengo, Ashley; Wang, Xiaozhao; Sugasawa, Keizo; Smith, Amos B.; Eckenhoff, Roderic G; Dmochowski, Ivan J.

    2013-01-01

    Recently, we identified 1-aminoanthracene as a fluorescent general anesthetic. To investigate the mechanism of action, a photoactive analogue, 1-azidoanthracene, was synthesized. Administration of 1-azidoanthracene to albino stage 40–47 tadpoles was found to immobilize animals upon near-UV irradiation of the forebrain region. The immobilization was often reversible, but it was characterized by a longer duration consistent with covalent attachment of the ligand to functionally important targets. IEF/SDS-PAGE examination of irradiated tadpole brain homogenate revealed labeled protein, identified by mass spectrometry as β-tubulin. In vitro assays with aminoanthracene-cross-linked tubulin indicated inhibition of microtubule polymerization, similar to colchicine. Tandem mass spectrometry confirmed anthracene binding near the colchicine site. Stage 40–47 tadpoles were also incubated 1 h with microtubule stabilizing agents, epothilone D or discodermolide, followed by dosing with 1-aminoanthracene. The effective concentration of 1-aminoanthracene required to immobilize the tadpoles was significantly increased in the presence of either microtubule stabilizing agent. Epothilone D similarly mitigated the effects of a clinical neurosteroid general anesthetic, allopregnanolone, believed to occupy the colchicine site in tubulin. We conclude that neuronal microtubules are “on-pathway” targets for anthracene general anesthetics and may also represent functional targets for some neurosteroid general anesthetics. PMID:23484901

  2. Approaching two-dimensional copolymers: photoirradiation of anthracene- and diaza-anthracene-bearing monomers in Langmuir monolayers.

    PubMed

    Payamyar, Payam; Servalli, Marco; Hungerland, Tim; Schütz, Andri P; Zheng, Zhikun; Borgschulte, Andreas; Schlüter, A Dieter

    2015-01-01

    By using structurally similar amphiphilic monomers, it is shown that compressed monolayers of varying amounts of such monomers at the air/water interface can be converted by photo-irradiation into the corresponding covalently connected monolayer sheets. Since one of the monomers carries three anthracene units and the other three 1,8-diaza-anthracene units, the growth reaction is proposed to take place through photochemically achieved [4+4]-cycloaddition between pairs of these units that are co-facially (face-to-face) arranged, to furnish the corresponding covalent dimers. While evidence for both homodimers is amply available, the existence of the heterodimer needs to be established with the help of a model reaction to support the conceptual aspect of this work, copolymerization in two dimensions. The sheet copolymers exhibit substantial robustness in that they can be spanned over 20 × 20 μm(2)-sized holes without rupturing under their own weight. X-ray photoelectron spectroscopy (XPS) studies reveal that the monomers are incorporated into the sheet copolymers according to feed. These results establish existence of the first covalent sheet copolymer, which is considered a step ahead towards novel 2D materials. PMID:25475710

  3. The onset of anthracene phototoxicity to Lemna gibba and the protective effects of humic acid

    SciTech Connect

    Gensemer, R.W.; Dixon, D.G.; Greenberg, B.M.

    1994-12-31

    The toxicity of anthracene to the freshwater duckweed Lemna gibba is strongly photo-induced in the presence of light containing natural levels of ultraviolet (UV) radiation. This was demonstrated using 8-day static renewal bioassays at an anthracene concentration of 2 mg-L{sup {minus}1}. Plants were incubated under simulated solar radiation (SSR) which mimics UV levels found in natural sunlight at a visible:UV-A:UV-B ratio of 100:10:1. Anthracene phototoxicity was expressed as inhibition of population growth and fluorescence induction decreases in chlorophyll content, and changes in low-temperature chlorophyll fluorescence emission scans. Furthermore, adding 6.2 mg-L-1 of an artificial humic acid ameliorated anthracene phototoxicity even though HA is also photo modified by UV light. However, anthracene inhibited photosynthesis days before the endpoint assays were performed. Therefore, the authors repeated these experiments at short time intervals following exposure to both light and chemical. Anthracene phototoxicity occurred after only 1 hour as detected by chlorophyll fluorescence induction, whereas chlorophyll contents and low-temperature fluorescence emission scans were not affected until 24--48 hours, respectively. Humic acid again ameliorated anthracene toxicity by delaying the negative physiological events by approximately 24 hours.

  4. Degradation and transformation of anthracene by white-rot fungus Armillaria sp. F022.

    PubMed

    Hadibarata, Tony; Zubir, Meor Mohd Fikri Ahmad; Rubiyatno; Chuang, Teh Zee; Yusoff, Abdull Rahim Mohd; Salim, Mohd Razman; Fulazzaky, Mohammad Ali; Seng, Bunrith; Nugroho, Agung Endro

    2013-09-01

    Characterization of anthracene metabolites produced by Armillaria sp. F022 was performed in the enzymatic system. The fungal culture was conducted in 100-mL Erlenmeyer flask containing mineral salt broth medium (20 mL) and incubated at 120 rpm for 5-30 days. The culture broth was then centrifuged at 10,000 rpm for 45 min to obtain the extract. Additionally, the effect of glucose consumption, laccase activity, and biomass production in degradation of anthracene were also investigated. Approximately, 92 % of the initial concentration of anthracene was degraded within 30 days of incubation. Dynamic pattern of the biomass production was affected the laccase activity during the experiment. The biomass of the fungus increased with the increasing of laccase activity. The isolation and characterization of four metabolites indicated that the structure of anthracene was transformed by Armillaria sp. F022 in two routes. First, anthracene was oxidized to form anthraquinone, benzoic acid, and second, converted into other products, 2-hydroxy-3-naphthoic acid and coumarin. Gas chromatography-mass spectrometry analysis also revealed that the molecular structure of anthracene was transformed by the action of the enzyme, generating a series of intermediate compounds such as anthraquinone by ring-cleavage reactions. The ligninolytic enzymes expecially free extracellular laccase played an important role in the transformation of anthracene during degradation period.

  5. Ratio of the concentration of anthraquinone to anthracene in coastal marine sediments.

    PubMed

    McKinney, R A; Pruell, R J; Burgess, R M

    1999-04-01

    The ratio of the concentration of the oxidation product anthraquinone to that of its parent polycyclic aromatic hydrocarbon anthracene is reported for several coastal marine sediments. The ratio ranges from 0.317 in a highly contaminated industrialized harbor to 2.81 in a remote, less contaminated site. We hypothesize that differences in this ratio result from the input source of PAHs, with input from atmospheric deposition at remote sites resulting in a predominance of anthraquinone (ratio > 1), and direct discharge to highly contaminated industrialized harbors resulting in a predominance of anthracene (ratio < 1). To support this hypothesis, the fate of anthracene in the marine environment was investigated with respect to conversion to its oxidation product, anthraquinone. Once associated with sediments, anthracene is believed to be relatively persistent; however, it can potentially be subjected to oxidation via biological (microbial degradation) and chemical (chemical oxidation and photooxidation) processes. An assessment of the extent of oxidation of anthracene associated with sediments was conducted both under conditions simulating those found in the marine environment and under rigorous conditions by exposure to UV radiation. Results of this study show that while anthracene associated with marine sediments does not readily undergo oxidation to anthraquinone under conditions normally encountered in the marine environment, under extreme conditions anthracene is photooxidized by exposure to UV radiation. The extent of oxidation is influenced by sediment characteristics such as percent organic carbon, humic acid content and sediment surface area. The relative stability of anthracene under normal conditions may help to validate the use of the anthraquinone to anthracene ratio in marine sediments as an environmental marker of contaminant source.

  6. Position Effect Based on Anthracene Core for OLED Emitters.

    PubMed

    Kang, Hyeonmi; Shin, Hwangyu; Kim, Beomjin; Park, Jongwook

    2016-03-01

    Green-orange emitters based on anthracene core have been successfully synthesized by substitution with triphenylamine side group in the 9, 10 or 2, 6 positions. There are larger blue shifts in the UV-visible absorption and PL spectra of the synthesized 2,6-substituted derivative compared to the 9,10-substituted derivative. When the synthesized compounds were used as emitting layers in non-doped OLED devices, a related trend was observed in their optical properties. In particular, the OLED device containing the 2,6-substituted derivative was found to exhibit excellent characteristics, with maximum EL emission at 518 nm, pure green emission with CIE coordinates of (0.334, 0.604), and external quantum efficiency of 2.83%.

  7. Photoluminescence and conductivity studies of anthracene-functionalized ruthenium nanoparticles

    NASA Astrophysics Data System (ADS)

    Chen, Wei; Pradhan, Sulolit; Chen, Shaowei

    2011-05-01

    Carbene-stabilized ruthenium nanoparticles were functionalized with anthryl moieties by olefin metathesis reactions with 9-vinylanthracene, at a surface concentration of about 19.7%, as estimated by 1H NMR spectroscopic measurements. Because of the conjugated metal-ligand interfacial bonding interactions, UV-vis measurements of the resulting nanoparticles showed a new broad absorption band centered at 612 nm, in addition to the peaks observed with monomeric vinylanthracene. FTIR measurements depicted apparent red-shifts of the aromatic vibrational stretches as compared to those of the monomeric vinylanthracene, suggestive of decreasing bonding order of the aromatic moieties as a result of extended conjugation between the particle-bound anthracene groups. Photoluminescence measurements confirmed the notion that effective intraparticle charge delocalization occurred by virtue of the conjugated metal-ligand interfacial bonding interactions, with apparent red-shifts of the excitation peaks and blue-shifts of the emission features, as compared to those of the monomeric vinylanthracene. The diminishment of the Stokes shift was, at least in part, attributed to the different chemical environments surrounding the anthryl moieties on the nanoparticle surface. Electronic conductivity measurements showed that because of the conjugated Ru z.dbd C π bonds, the activation energy for interparticle charge transport was about one order of magnitude lower than that observed with particles passivated by alkanethiolates. Additionally, whereas the original carbene-stabilized nanoparticles exhibited a semiconductor-metal transition within the temperature range of 100 to 320 K, anthracene-functionalized nanoparticles displayed apparent semiconducting behaviors with the ensemble conductivity increasing monotonically with temperature, most likely due to the disordering within the nanoparticle solids that arose from the different structures of the carbene ligands and anthryl moieties. These

  8. Biodegradation of naphthalene and anthracene by chemo-tactically active rhizobacteria of populus deltoides

    PubMed Central

    Bisht, Sandeep; Pandey, Piyush; Sood, Anchal; Sharma, Shivesh; Bisht, N. S.

    2010-01-01

    Several naphthalene and anthracene degrading bacteria were isolated from rhizosphere of Populus deltoides, which were growing in non-contaminated soil. Among these, four isolates, i.e. Kurthia sp., Micrococcus varians, Deinococcus radiodurans and Bacillus circulans utilized chrysene, benzene, toluene and xylene, in addition to anthracene and naphthalene. Kurthia sp and B. circulans showed positive chemotactic response for naphthalene and anthracene. The mean growth rate constant (K) of isolates were found to increase with successive increase in substrate concentration (0.5 to 1.0 mg/50ml). B. circulans SBA12 and Kurthia SBA4 degraded 87.5% and 86.6% of anthracene while, Kurthia sp. SBA4, B. circulans SBA12, and M. varians SBA8 degraded 85.3 %, 95.8 % and 86.8 % of naphthalene respectively after 6 days of incubation as determined by HPLC analysis. PMID:24031572

  9. Development of fluorescent lead II sensor based on an anthracene derived chalcone

    NASA Astrophysics Data System (ADS)

    Prabhu, J.; Velmurugan, K.; Nandhakumar, R.

    2015-06-01

    A simple anthracene based chalcone as a fluorescent chemosensor 1, capable of detecting Pb2+ in aqueous media, has been synthesized by the reaction between pyridine 2-carboxaldehyde and 9-acetyl anthracene. The Pb2+ recognition processes follows a photo induced electron transfer (PET) mechanism and are scarcely influenced by other coexisting metal ions. In addition, determination of lead in a variety of samples was also determined.

  10. Syntheses and Chemosensory of Anthracene and Phenanthrene Bisimide Derivatives

    NASA Technical Reports Server (NTRS)

    Bogusz, Zachary A.

    2004-01-01

    As the present technology of biochemical weapons advances, it is essential for science to attempt to prepare our nation for such an occurrence. Various areas of current research are devoted to precautionary measures and potential antidotes for national security. A practical application of these precautions would be the development of a chemical capable of detecting harmful gas. The benefits of being capable to synthesis a chemical compound that would warn and identify potentially deadly gases would ensure a higher level of safety. The chemicals in question can be generalized as bisimide anthracene derivatives. The idea behind these compounds is that in the presence of certain nerve gases, the compound will actually fluoresce, giving an indication that there is a strong likelihood of the presence of a nerve gas and ensure the proper precautionary measures are taken. The fluorescence is due to the quenching of an electric proton transfer within the structure of the molecule. The system proves to be very unique on account of the fact that the fluorescence can be "turned off" by reducing the system. By utilizing the synthesis designed by Dr. Faysal Ilhan, four distinct compounds can be synthesized through photochemical reactions involving para- and ortho- diketones. The photochemistry involved is very modem and much research is being devoted to fully understanding the possibilities and alternative applications of such materials. and meta-nitro anthracene bisimide (ABI-NO2), the amine of each (ABI-NH2), a para- and meta-nitro phenanthrene bisimjde (PBI-NO2), and the amine of each (PBI-NH2). Upon synthesizing these distinct compounds, I must then purify and analyze them in order to obtain any relevant trends, behaviors, and characteristics. The chemical composition analyses that will be conducted are the procedures taken by Dr. Daniel Tyson on previous experiments. The results generated from the data will point further research in the correct direction and hopefully

  11. Long-term reproductive and behavioral toxicity of anthracene to fish in the presence of solar ultraviolet radiation

    SciTech Connect

    Hall, A.T.; Oris, J.T.

    1994-12-31

    The long-term, low-level effects of anthracene in the presence of solar ultraviolet radiation (SUVR) were examined in the fathead minnow (Pimephales promelas). Adult fish exposed to anthracene exhibited reduced egg laying capacity, with altered oocyte maturation as a potential mechanism of action. Eggs and larvae maternally exposed to anthracene exhibited reduced hatching success and severe developmental abnormalities when incubated under SUVR. The combination of reduced egg output and developmental effects resulted in an inhibition in reproductive capacity in the range of 70--100%. Maternal transfer of anthracene to eggs was efficient; the BCF was 717 for maternally exposed eggs. However, anthracene deputation from eggs after oviposition with only maternal PAH exposure was rapid; anthracene half-life from eggs equaled 1.3 days. Exposure to anthracene under SUVR altered locomotor activity patterns in fathead minnows by inducing hyperactivity or hypoactivity during the light or dark phases of the photoperiod, respectively. Altered activity patterns indicated potential effects of anthracene on the nervous system and/or pineal gland. These alterations disrupted normal activity patterns and reproductive behaviors, and thus have major implications on a fish`s ability to survive and reproduce. Anthracene, a model phototoxic PAH, has many potential sites of toxic action, and any organism exposed to such contaminants will be an considerable SUVR-enhanced risk in the environment.

  12. Optical absorption of the anthracene and temperature-dependent capacitance-voltage characteristics of the Au/anthracene/n-Si heterojunction in metal-organic-semiconductor configuration

    NASA Astrophysics Data System (ADS)

    Kaçus, H.; Aydoğan, Ş.; Ekinci, D.; Kurudirek, S. V.; Türüt, A.

    2015-11-01

    An anthracene film has been deposited on an n-type silicon to fabricate an Au/anthracene/n-Si junction device. The band gap of the anthracene film has been determined from the optical measurement as Eg=1.65 eV. After the fabrication of the Au/anthracene/n-Si junction device, temperature dependent capacitance-voltage characteristics in the range of 160-300 K were studied to obtain the junction parameters of the device. The diffusion potential, barrier height, Fermi energy level and donor concentration parameters have been determined from the linear 1/C2-V curves with reverse bias at all temperatures. Both Fermi energy level and the barrier height increased with the increasing temperature. Temperature-dependence of the barrier height has been attributed to inhomogeneous barrier, traps and interface states. The ionized donor concentrations have varied with the temperature in an unsystematic manner due to the trapping/de-trapping of the charges at various temperatures.

  13. Formation of Bound Residues during Microbial Degradation of [14C]Anthracene in Soil

    PubMed Central

    Kästner, M.; Streibich, S.; Beyrer, M.; Richnow, H. H.; Fritsche, W.

    1999-01-01

    Carbon partitioning and residue formation during microbial degradation of polycyclic aromatic hydrocarbons (PAH) in soil and soil-compost mixtures were examined by using [14C]anthracenes labeled at different positions. In native soil 43.8% of [9-14C]anthracene was mineralized by the autochthonous microflora and 45.4% was transformed into bound residues within 176 days. Addition of compost increased the metabolism (67.2% of the anthracene was mineralized) and decreased the residue formation (20.7% of the anthracene was transformed). Thus, the higher organic carbon content after compost was added did not increase the level of residue formation. [14C]anthracene labeled at position 1,2,3,4,4a,5a was metabolized more rapidly and resulted in formation of higher levels of residues (28.5%) by the soil-compost mixture than [14C]anthracene radiolabeled at position C-9 (20.7%). Two phases of residue formation were observed in the experiments. In the first phase the original compound was sequestered in the soil, as indicated by its limited extractability. In the second phase metabolites were incorporated into humic substances after microbial degradation of the PAH (biogenic residue formation). PAH metabolites undergo oxidative coupling to phenolic compounds to form nonhydrolyzable humic substance-like macromolecules. We found indications that monomeric educts are coupled by C-C- or either bonds. Hydrolyzable ester bonds or sorption of the parent compounds plays a minor role in residue formation. Moreover, experiments performed with 14CO2 revealed that residues may arise from CO2 in the soil in amounts typical for anthracene biodegradation. The extent of residue formation depends on the metabolic capacity of the soil microflora and the characteristics of the soil. The position of the 14C label is another important factor which controls mineralization and residue formation from metabolized compounds. PMID:10223966

  14. Influences of humic acid and fulvic acid on horizontal leaching behavior of anthracene in soil barriers.

    PubMed

    Yu, Sheng; Li, Bang-Yu; Chen, Yi-Hu

    2015-12-01

    The influences of humic acid (HA) and fulvic acid (FA) on horizontal leaching behaviors of anthracene in barriers were investigated. Soil colloids (≤1 μm) were of concern because of their abilities of colloid-facilitated transport for hydrophobic organic compounds with soluble and insoluble organic matters. Through freely out of the barriers in the presence of soil colloids with FA added, the higher concentrations of anthracene were from 320 μg L(-1) (D1 and D3) to 390 μg L(-1) (D2 and D4) with 1 to 20 cm in length. The contents of anthracene were distributed evenly at 25 ng g(-1) dry weight (DW) (D1 and D3) and 11 ng g(-1) DW (D2 and D4) in barriers. Therefore, anthracene leaching behaviors were mainly induced by soil colloids with soluble organic matters. The insoluble organic matters would facilitate anthracene onto soil colloids and enhance the movement in and through porous media of soil matrix.

  15. Influences of humic acid and fulvic acid on horizontal leaching behavior of anthracene in soil barriers.

    PubMed

    Yu, Sheng; Li, Bang-Yu; Chen, Yi-Hu

    2015-12-01

    The influences of humic acid (HA) and fulvic acid (FA) on horizontal leaching behaviors of anthracene in barriers were investigated. Soil colloids (≤1 μm) were of concern because of their abilities of colloid-facilitated transport for hydrophobic organic compounds with soluble and insoluble organic matters. Through freely out of the barriers in the presence of soil colloids with FA added, the higher concentrations of anthracene were from 320 μg L(-1) (D1 and D3) to 390 μg L(-1) (D2 and D4) with 1 to 20 cm in length. The contents of anthracene were distributed evenly at 25 ng g(-1) dry weight (DW) (D1 and D3) and 11 ng g(-1) DW (D2 and D4) in barriers. Therefore, anthracene leaching behaviors were mainly induced by soil colloids with soluble organic matters. The insoluble organic matters would facilitate anthracene onto soil colloids and enhance the movement in and through porous media of soil matrix. PMID:26300357

  16. Biostimulation Reveals Functional Redundancy of Anthracene-Degrading Bacteria in Polycyclic Aromatic Hydrocarbon-Contaminated Soil

    PubMed Central

    Dunlevy, Sage R.; Singleton, David R.; Aitken, Michael D.

    2013-01-01

    Abstract Stable-isotope probing was previously used to identify bacterial anthracene-degraders in untreated soil from a former manufactured gas plant site. However, subsequent pyrosequence analyses of total bacterial communities and quantification of 16S rRNA genes indicated that relative abundances of the predominant anthracene-degrading bacteria (designated Anthracene Group 1) diminished as a result of biological treatment conditions in lab-scale, aerobic bioreactors. This study identified Alphaproteobacterial anthracene-degrading bacteria in bioreactor-treated soil which were dissimilar to those previously identified. The largest group of sequences was from the Alterythrobacter genus while other groups of sequences were associated with bacteria within the order Rhizobiales and the genus Bradyrhizobium. Conditions in the bioreactor enriched for organisms capable of degrading anthracene which were not the same as those identified as dominant degraders in the untreated soil. Further, these data suggest that identification of polycyclic aromatic hydrocarbon-degrading bacteria in contaminated but untreated soil may be a poor indicator of the most active degraders during biological treatment. PMID:24302851

  17. Green synthesis and characterization of ZnO nanoparticles for photocatalytic degradation of anthracene

    NASA Astrophysics Data System (ADS)

    Hassan, Saad S. M.; El Azab, Waleed I. M.; Ali, Hager R.; Mansour, Mona S. M.

    2015-12-01

    Zinc oxide nanoparticles were prepared using corriandrum sativum leaf extract and zinc acetate dihydrate. It was utilized as a photocatalyst for the degradation of anthracene. The catalyst was characterized by x-ray diffraction, high-resolution transmission electron microscopy, scanning electron microscopy, dynamic scattering light, Raman spectrometry and UV-vis spectrophotometry. The catalyst was used in a bench-scale design for degradation of anthracene. The factors affecting the photocatalytic degradation efficiency, including irradiation time, loading catalyst doses, and initial concentration of anthracene were investigated. The results obtained showed that the photocatalytic degradation efficiency was increased with both the decrease of the initial anthracene concentration and the increase of the photocatalyst doses. The optimum photocatalytic degradation was obtained at pH 7, irradiation time of 240 min and loading catalyst dose of 1000 μg L-1. Under these conditions, the photocatalytic degradation percentage of anthracene was 96%. The byproduct was the much less toxic (9, 10-anthraquinone) and a small amount of phthalic acid as confirmed by gas mass spectrometry and high-pressure liquid chromatography. The kinetic studies revealed that the photocatalytic degradation process obeyed the Langmuir-Hinshelwood model and followed a pseudo-first-order rate expression.

  18. Changes in bacterial community of anthracene bioremediation in municipal solid waste composting soil*

    PubMed Central

    Zhang, Shu-ying; Wang, Qing-feng; Wan, Rui; Xie, Shu-guang

    2011-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are common contaminants in a municipal solid waste (MSW) composting site. Knowledge of changes in microbial structure is useful to identify particular PAH degraders. However, the microbial community in the MSW composting soil and its change associated with prolonged exposure to PAHs and subsequent biodegradation remain largely unknown. In this study, anthracene was selected as a model compound. The bacterial community structure was investigated using terminal restriction fragment length polymorphism (TRFLP) and 16S rRNA gene clone library analysis. The two bimolecular tools revealed a large shift of bacterial community structure after anthracene amendment and subsequent biodegradation. Genera Methylophilus, Mesorhizobium, and Terrimonas had potential links to anthracene biodegradation, suggesting a consortium playing an active role. PMID:21887852

  19. Adsorption geometry of anthracene and 4-bromobiphenyl on TiO{sub 2}(110) surfaces

    SciTech Connect

    Potapenko, Denis; Choi, Nicholas; Osgood, Richard

    2010-01-01

    Adsorption of anthracene and 4-bromobiphenyl on a TiO{sub 2} rutile(110) surface has been studied under ultrahigh vacuum conditions with scanning tunneling microscopy (STM) and thermal programmed desorption (TPD). Multilayer and single-layer desorption peaks were observed at 270 and 360 K for anthracene and at 260 and 360 K for bromobiphenyl, respectively. STM images taken at room temperature show that both molecules form periodic patterns on the TiO{sub 2} surface with individual molecules aligned along the 5-coordinated Ti atom row of the substrate. Individual molecules of the organic adsorbates are mobile on the surface in the [001] direction parallel to the atomic rows. The observed lateral alignment of the molecules suggests attractive interactions in the case of anthracene and repulsive in the case of bromobiphenyl.

  20. The metabolism of anthracene and 9,10-dimethylanthracene by bacteria isolated from waters.

    PubMed

    Traczewska, T M; Ochocka, R; Lamparczyk, H

    1991-01-01

    The metabolism of two polycyclic aromatic hydrocarbons i.e. anthracene and 9,10-dimethylanthracene by Micrococcus sp., Pseudomonas sp. and Bacillus macerans was examined. The above compounds were used as a sole carbon source for their growth. Using the reversed-phase thin layer chromatography techniques a number of anthracene and 9,10-dimethylanthracene metabolites were isolated and their structures identified spectroscopically. These included anthracene and 9,10-dimethylanthracene cis-dihydrodiols, hydroxy-methyl-derivatives and various phenolic compounds. Bacteria metabolise hydrocarbons using the dioxygenase enzyme system, which differs from the mammalian cytochrome P-450 monoxygenase. Hence in addition rat liver microsomal metabolism of the above hydrocarbons was investigated using the same separation techniques.

  1. Distance-Dependent Triplet Energy Transfer between CdSe Nanocrystals and Surface Bound Anthracene.

    PubMed

    Li, Xin; Huang, Zhiyuan; Zavala, Ramsha; Tang, Ming Lee

    2016-06-01

    We investigate triplet energy transfer (TET) across variable-length aromatic oligo-p-phenylene and aliphatic bridges in a covalently linked CdSe nanocrystal (NC)-bridge-anthracene hybrid system. Photon upconversion measurements in saturated 9,10-diphenylanthracene hexane solutions under air-free conditions at room temperature provided the steady-state rate of TET (ket) across this interface. For flexible transmitters, ket is similar for different lengths of aliphatic bridges, suggesting that the ligands bend backward. For the rigid phenylene spacer, triplet sensitization of anthracene transmitter molecules by CdSe NCs shows a strong distance dependence, with a Dexter damping coefficient of 0.43 ± 0.07 Å(-1). The anthracene transmitter bound closest to the NC surface gave the highest quantum yield of 14.3% for the conversion of green to violet light, the current record for a hybrid platform. PMID:27164056

  2. Formation of bound residues during microbial degradation of [{sup 14}C]anthracene in soil

    SciTech Connect

    Kaestner, M.; Streibich, S.; Beyrer, M.; Fritsche, W.; Richnow, H.H.

    1999-05-01

    Carbon partitioning and residue formation during microbial degradation of polycyclic aromatic hydrocarbons (PAH) in soil and soil-compost mixtures were examined by using [{sup 14}C]anthracenes labeled at different positions. In native soil 43.8% of [9-{sup 14}C]anthracene was mineralized by the autochthonous microflora and 45.4% was transformed into bound residues within 176 days. Addition of compost increased the metabolism and decreased the residue formation (20.7% of the anthracene was transformed). Thus, the higher organic carbon content after compost was added did not increase the level of residue formation. [{sup 14}C]anthracene labeled at position 1,2,3,4,4a,5a was metabolized more rapidly and resulted in formation of higher levels of residues (28.5%) by the soil-compost mixture than [{sup 14}C]anthracene radiolabeled at position C-9 (20.7%). Two phases of residue formation were observed in the experiments. In the first phase the original compound was sequestered in the soil, as indicated by its limited extractability. In the second phase metabolites were incorporated into humic substances after microbial degradation of the PAH (biogenic residue formation). PAH metabolites undergo oxidative coupling to phenolic compounds to form nonhydrolyzable humic substance-like macromolecules. The authors found indications that monomeric educts are coupled by C-C- or either bonds. Hydrolyzable ester bonds or sorption of the parent compounds plays a minor role in residue formation. Moreover, experiments performed with {sup 14}CO{sub 2} revealed that residues may arise from CO{sub 2} in the soil in amounts typical for anthracene biodegradation. The extent of residue formation depends on the metabolic capacity of the soil microflora and the characteristics of the soil. The position of the {sup 14}C label is another important factor which controls mineralization and residue formation from metabolized compounds.

  3. Investigating the Reactivity of 1,4-Anthracene-Incorporated Cycloparaphenylene.

    PubMed

    Li, Penghao; Wong, Bryan M; Zakharov, Lev N; Jasti, Ramesh

    2016-04-01

    Cycloparaphenylenes (CPPs) and their derivatives are unique conjugated macrocycles with novel optoelectronic and host-guest properties. A better understanding of their reactivity is essential for creating new functional materials utilizing these strained aromatic molecules as building blocks. 1,4-Anthracene-incorporated CPP 1 was synthesized and exhibited Diels-Alder reactivity but was unable to photodimerize. Comparison studies with cyclophane 2 and unstrained 3 indicated that the distorted anthracene geometry is likely the major contributor to the anomalous reactivity of 1. PMID:27002794

  4. Interaction of atomic hydrogen with anthracene and polyacene from density functional theory

    NASA Astrophysics Data System (ADS)

    Ferullo, Ricardo M.; Castellani, Norberto J.; Belelli, Patricia G.

    2016-03-01

    The interaction of atomic hydrogen with two linear polycyclic aromatic hydrocarbons (PAHs), anthracene and polyacene (the polymer of benzene), was studied within the density functional theory (DFT). Using a proper dispersion-corrected method (DFT-D) the preferential physisorption sites were explored. The activation barrier for the bond formation between a peripheral C and the incoming H was calculated to be 58.5 and 34.1 meV with pure DFT on anthracene and polyacene at its antiferromagnetic ground state, respectively. DFT-D, although improves the description of the physisorbed state, tends to underestimate the chemisorption barriers due an artifact arising from the dispersion correction.

  5. Synthesis, crystal structures and photoluminescence of anthracen- and pyrene-based coumarin derivatives.

    PubMed

    Zhang, Hui; Tong, Hao; Zhao, Yuling; Yu, Tianzhi; Zhang, Peng; Li, Jianfeng; Fan, Duowang

    2015-11-01

    Two new anthracen- and pyrene-based coumarin derivatives, 3-(4-(anthracen-10-yl)phenyl)coumarin (4) and 3-(4-(pyrene-1-yl)phenyl)coumarin (5), were synthesized and characterized by FT-IR, (1)H NMR, element analysis and single crystal X-ray crystallography. The UV-vis absorption and photoluminescence spectra of these coumarin derivatives were investigated. The results show that compound 4 and 5 exhibit blue and blue-green emissions, respectively, under ultraviolet light excitation. Compared with the compound 4, the emission peak of compound 5 was bathochromically shifted by about 80 nm due to the more planar structure and larger π-conjugation.

  6. 2-(Anthracen-9-yl)-10-meth-oxy-benzo[h]quinoline acetone hemisolvate.

    PubMed

    Dong, Zhenming; Liu, Bo; Cui, Xinxin; Liu, Yufang

    2012-08-01

    The asymmetric unit of the title structure, C(28)H(19)NO·0.5C(3)H(6)O, comprises one 2-(anthracen-9-yl)-10-meth-oxy-benzo[h]-quinoline mol-ecule and an acteone mol-ecule with an occupany of 0.5. The solvent mol-ecule is disordered around a centre of symmetry. Its occupancy was determined from NMR data and kept fixed during the refinement. The two conjugated ring systems of the mol-ecule are almost perpendicular to each other; the inter-planar angle between the anthracene and quinoline ring systems is 84.9 (2)°. PMID:22904968

  7. Changes in the Bacterial Community Structure of Remediated Anthracene-Contaminated Soils

    PubMed Central

    Delgado-Balbuena, Laura; Bello-López, Juan M.; Navarro-Noya, Yendi E.; Rodríguez-Valentín, Analine; Luna-Guido, Marco L.; Dendooven, Luc

    2016-01-01

    Mixing soil or adding earthworms (Eisenia fetida (Savigny, 1826)) accelerated the removal of anthracene, a polycyclic aromatic hydrocarbon, from a pasture and an arable soil, while a non-ionic surfactant (Surfynol® 485) inhibited the removal of the contaminant compared to the untreated soil. It was unclear if the treatments affected the soil bacterial community and consequently the removal of anthracene. Therefore, the bacterial community structure was monitored by means of 454 pyrosequencing of the 16S rRNA gene in the pasture and arable soil mixed weekly, amended with Surfynol® 485, E. fetida or organic material that served as food for the earthworms for 56 days. In both soils, the removal of anthracene was in the order: mixing soil weekly (100%) > earthworms applied (92%) > organic material applied (77%) > untreated soil (57%) > surfactant applied (34%) after 56 days. There was no clear link between removal of anthracene from soil and changes in the bacterial community structure. On the one hand, application of earthworms removed most of the contaminant from the arable soil and had a strong effect on the bacterial community structure, i.e. a decrease in the relative abundance of the Acidobacteria, Chloroflexi and Gemmatimonadetes, and an increase in that of the Proteobacteria compared to the unamended soil. Mixing the soil weekly removed all anthracene from the arable soil, but had little or no effect on the bacterial community structure. On the other hand, application of the surfactant inhibited the removal of anthracene from the arable soil compared to the untreated soil, but had a strong effect on the bacterial community structure, i.e. a decrease in the relative abundance of Cytophagia (Bacteroidetes), Chloroflexi, Gemmatimonadetes and Planctomycetes and an increase in that of the Flavobacteria (Bacteroidetes) and Proteobacteria. Additionally, the removal of anthracene was similar in the different treatments of both the arable and pasture soil, but the

  8. Growth of optical-quality anthracene crystals doped with dibenzoterrylene for controlled single photon production

    SciTech Connect

    Major, Kyle D. Lien, Yu-Hung; Polisseni, Claudio; Grandi, Samuele; Kho, Kiang Wei; Clark, Alex S.; Hwang, J.; Hinds, E. A.

    2015-08-15

    Dibenzoterrylene (DBT) molecules within a crystalline anthracene matrix show promise as quantum emitters for controlled, single photon production. We present the design and construction of a chamber in which we reproducibly grow doped anthracene crystals of optical quality that are several mm across and a few μm thick. We demonstrate control of the DBT concentration over the range 6–300 parts per trillion and show that these DBT molecules are stable single-photon emitters. We interpret our data with a simple model that provides some information on the vapour pressure of DBT.

  9. Triphenylamine substituted anthracene derivatives for blue organic light-emitting diodes.

    PubMed

    Kwon, Sung Min; Lee, Kum Hee; Kim, Bo Young; Lee, Suk Jae; Kim, Young Kwan; Yoon, Seung Soo

    2014-08-01

    A series of bipolar anthracene derivatives containing triphenylamine as an electron donating group and pyridine, quinoline, isoquinoline and benzothiazole as electron withdrawing groups were synthesized and characterized. Particularly, a material, 9-quinolinyl-10-triphenylamin anthracene (3) exhibits a highly efficient sky-blue EL emission with the luminous efficiency (LE) of 9.36 cd/A, power efficiency (PE) of 5.94 lm/W and quantum efficiency (QE) of 4.23% at 500 nit. This material shows the maximum wavelength of the electroluminescence (EL) at 486 nm and the CIE x, y coordinates of (0.17, 0.36) at 6 V. PMID:25936082

  10. Modeling, Synthesis and Biological Evaluation of Potential Retinoid-X-Receptor (RXR) Selective Agonists: Novel Analogs of 4-[1-(3,5,5,8,8-Pentamethyl-5,6,7,8-tetrahydro-2-naphthyl)ethynyl]benzoic Acid (Bexarotene) and (E)-3-(3-(1,2,3,4-tetrahydro-1,1,4,4,6-pentamethylnaphthalen-7-yl)-4-hydroxyphenyl)acrylic acid (CD3254)

    PubMed Central

    Jurutka, Peter W.; Kaneko, Ichiro; Yang, Joanna; Bhogal, Jaskaran S.; Swierski, Johnathon C.; Tabacaru, Christa R.; Montano, Luis A.; Huynh, Chanh C.; Jama, Rabia A.; Mahelona, Ryan D.; Sarnowski, Joseph T.; Marcus, Lisa M.; Quezada, Alexis; Lemming, Brittney; Tedesco, Maria A.; Fischer, Audra J.; Mohamed, Said A.; Ziller, Joseph W.; Ma, Ning; Gray, Geoffrey M.; van der Vaart, Arjan; Marshall, Pamela A.; Wagner, Carl E.

    2014-01-01

    Three unreported analogs of 4-[1-(3,5,5,8,8-pentamethyl-5-6-7-8-tetrahydro-2-naphthyl)ethynyl]benzoic acid (1), otherwise known as bexarotene, as well as four novel analogs of (E)-3-(3-(1,2,3,4-tetrahydro-1,1,4,4,6-pentamethylnaphthalen-7-yl)-4-hydroxyphenyl)acrylic acid (CD3254) are described, and evaluated for their retinoid-X-receptor (RXR)-selective agonism. Compound 1 has FDA approval as a treatment for cutaneous T-cell lymphoma (CTCL); though, treatment with 1 can elicit side-effects by disrupting other RXR-heterodimer receptor pathways. Of the 7 modeled novel compounds, all analogs stimulate RXR-regulated transcription in mammalian-2-hybrid and RXRE-mediated assays, possess comparable or elevated biological activity based on EC50 profiles, and retain similar or improved apoptotic activity in CTCL assays compared to 1. All novel compounds demonstrate selectivity for RXR and minimal crossover onto the retinoic-acid-receptor (RAR) compared to all-trans-retinoic acid, with select analogs also reducing inhibition of other RXR-dependent pathways (e.g., VDR-RXR). Our results demonstrate that further improvements in biological potency and selectivity of bexarotene can be achieved through rational drug design. PMID:24180745

  11. Synthesis and electroluminescent properties of anthracene derivatives containing electron-withdrawing oxide moieties

    SciTech Connect

    Yoon, Jhin-yeong; Na, Eun Jae; Park, Soo Na; Lee, Seok Jae; Kim, Young Kwan; Yoon, Seung Soo

    2014-10-15

    Highlights: • Blue fluorescent material is important for application in full-color displays. • We have synthesized emitters based on anthracene connected with oxide moieties. • 1C shows a highly efficient blue EL emission due to electron-injection property. - Abstract: A series of new blue-emitting materials: (4-(10-(naphthalen-2-yl)anthracen-9-yl)phenyl)(phenyl)methanone (1); 9-(naphthalen-2-yl)-10-(4-((diphenyl)phosphine oxide)phenyl)anthracene (2); 9-(naphthalen-2-yl)-10-(4-(phenylsulfonyl)phenyl)anthracene (3) were designed and synthesized via Suzuki cross-coupling reaction. Multilayer OLEDs were fabricated in the following sequence: ITO (180 nm)/NPB (50 nm)/blue materials 1–3 (30 nm)/TPBi (15 nm)/Liq (2 nm)/Al (100 nm). All devices showed the efficient blue EL emissions. In particular, the device using 1 as an emitter exhibited efficient blue electroluminescent properties with a maximum luminous, power, external quantum efficiency and CIE coordinates of 0.36 cd/A, 0.90 lm/W, 0.55% at 20 mA/cm{sup 2} and (x = 0.16, y = 0.20) at 10.0 V, respectively.

  12. Oxygen radical production in bluegill sunfish liver microsomes exposed to anthracene and UV radiation

    SciTech Connect

    Choi, J.; Oris, J.

    1995-12-31

    Many polycyclic aromatic hydrocarbons (PAHs) are acutely toxic to fish in the presence of ultraviolet radiation. Oxygen radicals are very reactive and are responsible for many cellular injuries including membrane peroxidation and DNA fragmentation. In this research increased oxygen radical production was hypothesized for the mechanism of UV-PAH acute toxicity. In order to test this hypothesis Bluegill sunfish (Lepomis machrochirus) liver microsomes were exposed to anthracene and UV radiation in four different combinations: (No UV + No Ant), (No UV + Ant), (UV + No Ant), (UV + Ant). The production of superoxide anion was quantified by measuring the spectrophotometric absorbance of acetylated cytochrome c, which is reduced by superoxide anion. 1 ml of reaction solution contained 1 mg of microsomes and, for Ant treatments, 7.7 {micro}g of anthracene. After 3 hours preincubation, acetylated cytochrome c solution was added. The UV treatment groups were exposed to UV-A for 20 minutes at 37 C. The highest mean concentration of reduced acetylated cytochrome c was found in the UV + Ant treatment group and it was significantly different from all other treatment groups. No significant differences were observed among the other three treatment groups. This result coincides with previous studies revealing that anthracene is acutely toxic to fish only under UV radiation, and it implies that the photoinduced toxicity of anthracene, as well as other PAHs, is manifested by the action of oxygen radicals.

  13. A new tandem reaction of benzyne: one-pot synthesis of aryl amines containing anthracene.

    PubMed

    Xie, Chunsong; Zhang, Yuhong

    2007-03-01

    [reaction: see text] The reaction of benzyne with N-substituted imidazoles affords a novel way to prepare arylamines containing anthracene under very mild conditions. This transformation is assumed to proceed via a tandem reaction involving a Diels-Alder reaction and an intermolecular nucleophilic coupling reaction.

  14. Assessment of anthracene toxicity toward environmental eukaryotic microorganisms: Tetrahymena pyriformis and selected micromycetes.

    PubMed

    Bonnet, J L; Guiraud, P; Dusser, M; Kadri, M; Laffosse, J; Steiman, R; Bohatier, J

    2005-01-01

    The toxicity of anthracene, a nonmutagenic, noncarcinogenic, low-molecular-weight polycyclic aromatic hydrocarbon present in the environment, was assessed using a ciliated protozoan, Tetrahymena pyriformis, and a selection of 10 micromycetes from different taxonomic groups living in two environmental compartments, namely aquatic and soil ecosystems. With T. pyriformis, a concentration-dependent inhibitory effect was shown on the cell proliferation rate, IC(50) = 33.40+/-4.84 mg/L (kinetic method). Phagocytosis of nonsoluble anthracene was confirmed by the presence of digestive vacuoles with photon microscopy. In fungi, anthracene did not exhibit a fungicide effect but showed a fungistatic action. Except for Absidia fusca and Cladosporium herbarum, the micromycetes showed a concentration-dependent decrease in growth. From IC(50) values determined by endpoint or kinetic methods, Rhodotorula glutinis and all of the Ascomycotina (except for Penicillium chrysogenum) were the most sensitive species, while Phanerochaete chrysosporium, P. chrysogenum, and the two Deuteromycotina were more resistant to anthracene. Our discussion focuses on the evaluation of toxicity by the two methods used for the calculation of the IC(50) values (endpoint and kinetic), the advantages of studying growth by a kinetic method (the dynamic aspect), and a comparison of toxicity to T. pyriformis and the different micromycetes.

  15. Exploiting anthracene photodimerization within peptides: light induced sequence-selective DNA binding.

    PubMed

    Bullen, Gemma A; Tucker, James H R; Peacock, Anna F A

    2015-05-11

    The unprecedented use of anthracene photodimerization within a protein or peptide system is explored through its incorporation into a DNA-binding peptide, derived from the GCN4 transcription factor. This study demonstrates an effective and dynamic interplay between a photoreaction and a peptide-DNA assembly, with each process able to exert control over the other.

  16. Tethered anthracene pair as molecular tweezers for post-production separation of single-walled carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Anderson, Ankoma; Yang, Fengchun; Cao, Li; Li, Huaping; Meziani, Mohammed J.; Sun, Ya-Ping

    2016-07-01

    As-produced single-walled carbon nanotubes (SWNTs) are metallic and semiconducting mixtures. An anthracene mono-derivative with a long alkyl tail and a molecule with a tethered pair of anthracene species (bis-anthracene) in a "molecular tweezers"-like configuration were synthesized and evaluated for the separation of SWNTs. While the mono-derivative was incapable of the noncovalent functionalization-solubilization, the bis-anthracene was found to be very effective. The results suggest that molecular tweezers of a tethered pair of planar aromatic species can be coupled with the selection of a suitable solvent or solvent mixture for effective and efficient post-production separation of metallic and semiconducting SWNTs.

  17. Quinoline-Substituted 10-(naphthalene-7-yl)anthracene Derivatives for Blue Fluorescent Organic Light-Emitting Diodes.

    PubMed

    Kim, Chanwoo; Park, Soo Na; Lee, Seul Bee; Kim, Young Seok; Lee, Ho Won; Kim, Young Kwan; Yoon, Seung Soo

    2016-02-01

    In this study, we have designed and synthesized blue emitters based on quinoline-substituted 10-(naphthalene-7-yl)anthracene. Particularly, a material exhibited highly efficient blue electroluminescence with CIE coordinates of (0.15, 0.18).

  18. Flocculant in wastewater affects dynamics of inorganic N and accelerates removal of phenanthrene and anthracene in soil.

    PubMed

    Fernandez-Luqueno, F; Thalasso, F; Luna-Guido, M L; Ceballos-Ramírez, J M; Ordoñez-Ruiz, I M; Dendooven, L

    2009-06-01

    Recycling of municipal wastewater requires treatment with flocculants, such as polyacrylamide. It is unknown how polyacrylamide in sludge affects removal of polycyclic aromatic hydrocarbons (PAH) from soil. An alkaline-saline soil and an agricultural soil were contaminated with phenanthrene and anthracene. Sludge with or without polyacrylamide was added while emission of CO(2) and concentrations of NH(4)(+), NO(3)(-), NO(2)(-), phenanthrene and anthracene were monitored in an aerobic incubation experiment. Polyacrylamide in the sludge had no effect on the production of CO(2), but it reduced the concentration of NH(4)(+), increased the concentration of NO(3)(-) in the Acolman soil and NO(2)(-) in the Texcoco soil, and increased N mineralization compared to the soil amended with sludge without polyacrylamide. After 112d, polyacrylamide accelerated the removal of anthracene from both soils and that of phenanthrene in the Acolman soil. It was found that polyacrylamide accelerated removal of phenanthrene and anthracene from soil.

  19. Dynamic covalent bond based on reversible photo [4 + 4] cycloaddition of anthracene for construction of double-dynamic polymers.

    PubMed

    Xu, Jiang-Fei; Chen, Yu-Zhe; Wu, Li-Zhu; Tung, Chen-Ho; Yang, Qing-Zheng

    2013-12-20

    Dynamic covalent bonds supplied by reversible anthracene dimerization were combined with pillar[5]arene/imidazole host-guest interactions to construct double-dynamic polymers. Heating such polymers (in solution or as a gel) led to depolymerization by dissociation of either the host-guest complexes alone or the complexes and the anthracene dimers, depending on the extent of heating. The polymers reformed readily upon cooling or irradiation.

  20. Molecular dynamics of dibenz[a,h]anthracene and its metabolite interacting with lung surfactant phospholipid bilayers.

    PubMed

    Padilla-Chavarría, Helmut I; Guizado, Teobaldo R C; Pimentel, Andre S

    2015-08-28

    The interaction of dibenz[a,h]anthracene and its ultimate carcinogenic 3,4-diol-1,2-epoxide with lung surfactant phospholipid bilayers was successfully performed using molecular dynamics. The DPPC/DPPG/cholesterol bilayer (64 : 64 : 2) was used as the lung surfactant phospholipid bilayer model and compared with the DPPC bilayer as a reference. Dibenz[a,h]anthracene and its 3,4-diol-1,2-epoxide were inserted in water and lipid phases in order to investigate their interactions with the lung surfactant phospholipid bilayers. The radial distribution function between two P atoms in polar heads shows that the 3,4-diol-1,2-epoxide affects the order between the P atoms in the DPPC/DPPG/cholesterol model more than dibenz[a,h]anthracene, which is a consequence of its preference for the polar heads and dibenz[a,h]anthracene prefers to be located in the hydrocarbon chain of the phospholipid bilayers. Dibenz[a,h]anthracene and its 3,4-diol-1,2-epoxide may form aggregates in water and lipid phases, and in the water-lipid interface. The implications for the possible effect of dibenz[a,h]anthracene and its 3,4-diol-1,2-epoxide in the lung surfactant phospholipid bilayers are discussed.

  1. The response of Hyalella azteca to artificial sediments spiked with cadmium, zinc, and anthracene

    SciTech Connect

    Sawyer, L.N.; Burton, G.A. Jr.

    1995-12-31

    Two artificial sediment recipes with differing organic content have been found that give > 80%. control survival with Hyalella azteca in standard toxicity assays. To further explore the usefulness of these sediments, both were spiked with cadmium, zinc, and anthracene. Toxicity assays (96 hr.) were run at intervals up to 4 weeks post-spike. Consistent LC50 results were obtained for both sediments and both metals. Responses with the PAH were similar to the metals, but each test was placed under UV light to assess photo-induced toxicity. GC analysis on porewater indicates that anthracene either binds tightly to the sediment or is absorbed directly by Hyalella azteca. Toxicity decreased over time, perhaps due to this binding. Both sediments appear to be adequate as routine control sediments.

  2. Inhibiting the photosensitized oxidation of anthracene and tryptophan by means of natural antioxidants

    NASA Astrophysics Data System (ADS)

    Aksenova, N. A.; Vyzhlova, E. N.; Malinovskaya, V. V.; Parfenov, V. V.; Solov'eva, A. B.; Timashev, P. S.

    2013-08-01

    It is shown that model reactions of photosensitized oxidation of anthracene and tryptophan can be used for evaluation and comparison of antioxidant activity of various classes of compounds. Inhibition of the oxidation of substrates in the presence of the familiar antioxidants tocopherol (vitamin E), ascorbic acid (vitamin C), and mixtures of these vitamins with methionine, and in the presence of reputed antioxidants dihydroquercetin and taurine, are considered. It is concluded that all of the above compounds except for taurine have antioxidant properties; i.e., they reduce the rate constants of the photosensitized oxidation of anthracene and tryptophan. It is found that the inhibition of oxidation is associated with the interaction between antioxidants and singlet oxygen. Analysis of the kinetic dependences of the photosensitized oxidation of substrates in the presence of antioxidants reveals that a mixture of vitamins inhibits the process most efficiently, and inhibition occurs at the initial stages due to more active interaction between singlet oxygen and vitamin C

  3. Diffusion of anthracene derivatives on Cu(111) studied by STM and DFT

    NASA Astrophysics Data System (ADS)

    Wyrick, Jonathan; Bartels, Ludwig; Einstein, Theodore

    2014-03-01

    Substituted anthracenes have drawn attention due to their ability to diffuse uniaxially on a Cu(111) surface. We compare anthracene to three of its derivatives whose 9,10 hydrogens are replaced by elements of the chalcogen group that act as linkers binding the molecules to a Cu(111) substrate. DFT calculations shed light on STM imaging and diffusion studies on the three substituted species. We present an analysis of the DFT results in which energetic contributions to the diffusion barriers are partitioned among the Kohn-Sham orbitals, allowing us to make assignments as to how each orbital affects diffusion for each species and draw comparisons between them. Present address: Center for Nanoscale Science and Technology, NIST, Gaithersburg, MD.

  4. Influence of exposure time on the biotransformation rate of benzo(a)anthracene in fish

    SciTech Connect

    Maagd, P.G.J. de; Poorte, J. de; Sijm, D.T.H.M.; Opperhuizen, A.

    1995-12-31

    Biotransformation of PAH can yield in the formation of carcinogenic metabolites, therefore, determining the rate at which metabolites are formed is of importance to risk assessment. Biotransformation rates can be affected by inducing agents, hormonal status, temperature etc. To determine if biotransformation rates of PAH are influenced by auto-induction, juvenile fathead minnows were exposed to benzo(a)anthracene in water for various exposure times. After exposure for 5, 10, 24, 72, 168 or 336 hours no significant differences between biotransformation rates were found. The variation within each biotransformation rate was less than 20%. From these findings it is concluded that auto-induction by benzo(a)anthracene does not occur in fathead minnow.

  5. Semiempirical molecular orbital estimation of the relative stability of bianthryls produced by anthracene pyrolysis

    SciTech Connect

    Mulholland, J.A.; Mukherjee, J.; Wornat, M.J.; Sarofim, A.F.; Rutledge, G.C. . Dept. of Chemical Engineering)

    1993-08-01

    The pyrolysis of pure anthracene at temperatures between 1,200 and 1,500 K produced all six bianthryl isomers whose relative yields appear to be related to steric factors. To evaluate the hypothesis that thermodynamic factors govern the product distribution of bianthryls in this system, the relative enthalpies and entropies of biaryl isomers were estimated by molecular orbital modeling, using the semiempirical AM1 (Austin Model 1). Computational analysis of several isomer sets demonstrates that the relative stabilities of a large number of biaryl isomers are determined largely by steric interactions caused by structural features defined as bays, coves, and fjords. These steric factors affect both the degree of biaryl twist in the preferred conformation and the freedom of internal rotation. Molecular orbital modeling supports the hypothesis that a thermodynamic distribution of bianthryl isomers is produced by anthracene pyrolysis.

  6. Synthesis and Luminescent Property of Poly(9-(3-vinyl-phenyl)-anthracene).

    PubMed

    Lee, Sunmi; Shin, Hwangyu; Park, Beom-Soo Michael; Lee, Jaehyun; Park, Jongwook

    2015-07-01

    Polymer light-emitting diodes (PLEDs) have attracted much attention from academia and industry field because of their various applications such as large area flat-panel displays and lightings. In this paper, we suggest new blue emitting polymer based on anthracene, Poly(9-(3-Vinyl-phenyl)-anthracene) (PVPA). From NMR data, vinyl group protons were disappeared and aromatic protons showed broad proton peaks because of polymer characteristics. PVPA had film property well and it exhibited vivid PL maximum values of 431, 455, 482 nm and broad PL spectrum. Three dopants for green, red, yellow were used to PVPA, all energy transfer was happened well. By using rubrene dopant of yellow emission, doped film provided white PL. PMID:26373155

  7. Degradation of Phenanthrene and Anthracene by Cell Suspensions of Mycobacterium sp. Strain PYR-1

    PubMed Central

    Moody, Joanna D.; Freeman, James P.; Doerge, Daniel R.; Cerniglia, Carl E.

    2001-01-01

    Cultures of Mycobacterium sp. strain PYR-1 were dosed with anthracene or phenanthrene and after 14 days of incubation had degraded 92 and 90% of the added anthracene and phenanthrene, respectively. The metabolites were extracted and identified by UV-visible light absorption, high-pressure liquid chromatography retention times, mass spectrometry, 1H and 13C nuclear magnetic resonance spectrometry, and comparison to authentic compounds and literature data. Neutral-pH ethyl acetate extracts from anthracene-incubated cells showed four metabolites, identified as cis-1,2-dihydroxy-1,2-dihydroanthracene, 6,7-benzocoumarin, 1-methoxy-2-hydroxyanthracene, and 9,10-anthraquinone. A novel anthracene ring fission product was isolated from acidified culture media and was identified as 3-(2-carboxyvinyl)naphthalene-2-carboxylic acid. 6,7-Benzocoumarin was also found in that extract. When Mycobacterium sp. strain PYR-1 was grown in the presence of phenanthrene, three neutral metabolites were identified as cis- and trans-9,10-dihydroxy-9,10-dihydrophenanthrene and cis-3,4-dihydroxy-3,4-dihydrophenanthrene. Phenanthrene ring fission products, isolated from acid extracts, were identified as 2,2′-diphenic acid, 1-hydroxynaphthoic acid, and phthalic acid. The data point to the existence, next to already known routes for both gram-negative and gram-positive bacteria, of alternative pathways that might be due to the presence of different dioxygenases or to a relaxed specificity of the same dioxygenase for initial attack on polycyclic aromatic hydrocarbons. PMID:11282593

  8. (E)-4-[(4-nitrophenyl)diazenyl]phenyl anthracene-9-carboxylate.

    SciTech Connect

    Vance, Andrew L.; Zifer, Thomas; Nichol, Jessica L.; Rodriguez, Mark Andrew; Leonard, Francois Leonard; Wong, Bryan Matthew

    2008-10-01

    In the title compound, C{sub 27}H{sub 17}N{sub 3}O{sub 4}, the azo group displays a trans conformation and the dihedral angles between the central benzene ring and the pendant anthracene and nitrobenzene rings are 82.94 (7) and 7.30 (9){sup o}, respectively. In the crystal structure, weak C-H...O hydrogen bonds, likely associated with a dipole moment present on the molecule, help to consolidate the packing.

  9. Discovery of novel dihydro-9,10-ethano-anthracene carboxamides as glucocorticoid receptor modulators.

    PubMed

    Yang, Bingwei V; Vaccaro, Wayne; Doweyko, Arthur M; Doweyko, Lidia M; Huynh, Tram; Tortolani, David; Nadler, Steven G; McKay, Lorraine; Somerville, John; Holloway, Deborah A; Habte, Sium; Weinstein, David S; Barrish, Joel C

    2009-04-15

    A series of dihydro-9,10-ethano-anthracene-11-carboxamides as novel glucocorticoid receptor modulators is reported. SAR exploration identified compounds from this series displaying a promising dissociation profile in discriminating between transrepression and transactivation activities. 17a is a partial agonist of GR-mediated transactivation which elicits potent and efficacious transrepression in reporter gene assays. A hypothetical binding mode is provided which accounts for the induction of functional activity by a bridgehead methyl group. PMID:19321341

  10. Formation of 7-hydroxymethyl-12-methylbenz(a)anthracene-DNA adducts from 7,12-dimethylbenz(a)anthracene in mouse epidermis

    SciTech Connect

    DiGiovanni, J.; Nebzydoski, A.P.; Decina, P.C.

    1983-09-01

    The formation of DNA adducts from (/sup 3/H)-7-hydroxymethyl-12-methylbenz(a)anthracene (7-OHM-12-MBA) and (/sup 3/H)-7,12-dimethylbenz(a)anthracene (DMBA) in the epidermis of Sencar mice was analyzed. Comparison of Sephadex LH-20 chromatographic profiles of DNA samples isolated from mice treated with DMBA or 7-OHM-12-MBA suggested that the DMBA-treated animals contained DNA adduct(s) derived from the further metabolism of 7-OHM-12-MBA. Further analysis of DNA samples from DMBA-treated mice by high-pressure liquid chromatography demonstrated the presence of 5 DNA adducts which were chromatographically indistinguishable from the DNA adducts formed in 7-OHM-12-MBA-treated mice. Epidermal homogenates were utilized to catalyze the covalent binding of (/sup 3/H)DMBA and (/sup 3/H)-7-OHM-12-MBA to calf thymus DNA in vitro. Under conditions of limiting concentrations of (/sup 3/H)DMBA, the majority of the DNA adducts formed chromatographed in regions where 7-OHM-12-MBA-DNA adducts eluted. A major DMBA-DNA adduct formed in this in vitro system eluted with the same retention time as did the major 7-OHM-12-MBA-DNA adduct formed in mouse skin in vivo. These results when coupled with the in vivo data suggest that 7-OHM-12-MBA is an intermediate for at least some of the binding of DMBA to epidermal DNA in Sencar mice.

  11. Dual photochemistry of anthracene-9,10-endoperoxide studied by femtosecond spectroscopy.

    PubMed

    Lauer, Alexandra; Dobryakov, Alexander L; Kovalenko, Sergey A; Fidder, Henk; Heyne, Karsten

    2011-05-21

    The dual photochemistry of anthracene-9,10-endoperoxide (APO) was investigated in a fs UV pump-supercontinuum probe experiment, along with anthracene (AC) and anthraquinone (AQ) for comparison. Excitation of APO at 282 nm leads to 100% product formation by two competing photoreaction channels. Cycloreversion generates with a ∼25% quantum yield (QY) (1)O(2) and AC vibrationally excited in the singlet electronic ground state (hot AC). 1-2% of the AC is generated in the lowest triplet state, but no AC is generated in electronically excited singlet states. Generation and cooling of hot AC are modeled using solution phase and broadened gas-phase AC absorption spectra at various temperatures. Results indicate ultrafast generation of hot AC within 3 ps, much faster than reported before for derivatives of anthracene endoperoxide, and subsequent cooling with an 18 ps time constant. The homolytic O-O cleavage pathway generates a biradical, which converts into electronically excited diepoxide (DE). Our data indicate a 1.5 ps time constant that we tentatively assign to the biradical decay and DE formation. Cooling of DE in this electronically excited state takes place with a ∼21 ps time constant. Excitation of AQ at 266 nm is followed by an ultrafast population of the T(1)(nπ*) triplet state of AQ with a time constant of (160 ± 60) fs.

  12. Oxidation of anthracene on platinum macro- and micro-electrodes: Sonoelectrochemical, cryoelectrochemical and sonocryoelectrochemical studies.

    PubMed

    Paddon, Christopher A; Banks, Craig E; Davies, Ieuan G; Compton, Richard G

    2006-02-01

    The electro- and sonoelectro-chemical oxidation of anthracene in acetonitrile has been explored at room and low temperature (-40 degrees C) at a platinum micro- and macro-electrode, respectively. From both methodologies, the effective number of electrons, n(eff), in the oxidation process is evaluated at both room temperature and at the limit of the solvent-electrolyte freezing point. It is observed that n(eff) is close to 1 at low temperature while at room temperature it is higher, indicating sluggish follow up kinetics at lower temperature. The oxidative electrolysis of anthracene within an undivided cell, under various conditions is investigated with the product(s) obtained analysed and quantified by (1)H NMR. At room temperature under both 'silent' and 'sono' conditions the electrochemical oxidation produces 9,10-anthraquinone and bianthrone while at low temperature with acoustic streaming, anthracene-9,10-diol is additionally produced. Electrolyses with intentionally added water and also with oxygen saturation is investigated and its influence on the reaction pathway reported. In particular, the addition of water (1.4M) favours the formation of anthraquinone in a 3:1 ratio with bianthrone. Overall, the effect of lower temperature is to favour the formation of anthraquinone or its reduced form whilst the addition of insonation at low temperature is to substantially enhance the product yield per Coulomb of charge injected.

  13. Single naphthalene and anthracene molecular junctions using Ag and Cu electrodes in ultra high vacuum

    NASA Astrophysics Data System (ADS)

    Fujii, Shintaro; Kaneko, Satoshi; Chenyang, Liu; Kiguchi, Manabu

    2015-11-01

    We present a charge transport study on single naphthalene and anthracene molecular junctions wired into Ag and Cu electrodes using mechanically controllable break junction technique at 100 K under ultra-high vacuum condition. In particular we focus on effect of metal-π interaction on the formation probability of the molecular junctions. We found that the single molecular junctions of the acene molecules (e.g. naphthalene and anthracene) exhibit highly conductive character below 0.2 G0 (G0 = 2e2/h). The acene molecular junctions displayed formation probability of ca. 20% for Ag system and >40% for Cu system. The high formation probability of the molecular junctions with respect to benzene/Au junctions can be qualitatively explained by size effect, in which larger molecules of the naphthalene and anthracene can effectively bridge the gap between metal electrodes compared with small molecule such as benzene. The acene/Cu junctions displayed higher formation probability than the acene/Ag junctions. This result demonstrated that not only the size effect but the degree of the metal-π interaction have to be taken into account to quantitatively evaluate the formation probability of the molecular junctions for Ag and Cu system.

  14. The effects of ultraviolet radiation and the polycyclic aromatic hydrocarbon, anthracene, on algae

    SciTech Connect

    Gala, W.R.

    1989-01-01

    The direct effects of ultraviolet (UV) radiation and the photoinduced toxicity of polycyclic aromatic hydrocarbons (PAH) to algae have been assessed. The penetration of solar UV radiation into offshore Lake Michigan was characterized. The direct effects of solar UV radiation to the primary production of natural phytoplankton assemblages in Lake Michigan was determined utilizing in situ incubations in chambers which selectively removed portions of the solar UV spectrum. A predictive hazard assessment model to estimate the impact of current and potential UV intensities on total lake productivity was developed. The photo-induced toxicity of the linear 3-ring PAH, anthracene, to the green alga, Selenastrum capricornutum, was characterized. The dose-response relationships among anthracene concentration, UV radiation intensity, and algal growth rate, {sup 14}C-bicarbonate incorporation, and flow cytometric endpoints were determined. The potential environmental hazard of PAH contamination to algal communities was assessed. Fluridone, a carotenoid biosynthesis inhibiting herbicide, was utilized to investigate possible sites and modes of toxic action and the protection provided by carotenoids in algal cells to the photo-induced toxicity of anthracene. It was concluded that solar UV radiation at current UV intensities can have considerable impact on natural algal communities through the direct effects of UV radiation and indirectly due to the photo-induced toxicity of PAH. However, stratospheric ozone depletion and the concomitant increase in solar UV radiation which is currently predicted will have negligible effects on primary production of phytoplankton assemblages in the Great Lakes.

  15. Control of the intermolecular photodimerization of anthracene derivatives by hydrogen bonding of urea groups in dilute solution.

    PubMed

    Matsumoto, Hisato; Nishimura, Yoshinobu; Arai, Tatsuo

    2016-08-01

    The photodimerization reaction of anthracene derivatives was performed by capitalizing on intermolecular hydrogen bonds. Anthracene derivatives that can control the dimerization reaction depending on the substitution site were designed by using two anthryl moieties and one urea group, referred to as N,N'-dianthracen-n-ylurea, nDAU (n = 1, 2 and 9), which are symmetrically substituted by 1-anthryl, 2-anthryl and 9-anthryl groups, respectively. We investigated the excimer emission and photodimerization reaction of these anthracene-urea derivatives using absorption, emission, and (1)H NMR spectroscopy along with fluorescence decay measurements. All derivatives showed a concentration dependence of their fluorescence spectra and multiple fluorescence lifetime components even at 10(-6) M. Significantly, 9DAU resulted in an intermolecular photodimerization reaction. These differences in photoreactivity of nDAU may depend on variations in the overlap of the intermolecularly associated anthracene rings of nDAU by hydrogen bonding between intermolecular urea moieties. Furthermore, the dimerization quantum yield of 9DAU was reduced by the addition of tetrabutylammonium acetate (TBAAc). Consequently, we revealed that the substitution site and the addition of TBAAc affected the dimerization reaction of anthracene-urea derivatives. PMID:27444124

  16. Iptycene synthesis: A new method for attaching a 2,3-anthracene moiety to the 9,10-positions of another anthracene moiety - Exceptional conditions for a Lewis acid catalyzed Diels-Alder reaction

    NASA Technical Reports Server (NTRS)

    Chen, Yong-Shing; Hart, Harold

    1989-01-01

    An efficient three-step method for appending a 2,3-anthracene moiety to the 9,10-positions of an existing anthracene moiety is described. The first step uses excess 1,4-anthraquinone (3 equiv) and aluminum chloride (6 equiv) to obtain the anthracene-quinone cycloadduct (omission of the AlCl3 resulted in no adduct). The resulting diketone was reduced to the corresponding diol (excess LiAlH4), which was dehydrated to the arene with phosphorus oxychloride and pyridine. Specific examples include the preparation of heptipycene 8 from pentiptycene 6 (66 percent overall yield) and a similar conversion of 8 to the noniptycene 13 (75 percent overall yield). The methodology led to a markedly improved synthesis of tritriptycene 9 and the first synthesis of undecaiptycene 14.

  17. Calculation and spectroscopic assignment of charge-transfer states in solid anthracene, tetracene and pentacene

    NASA Astrophysics Data System (ADS)

    Bounds, P. J.; Siebrand, W.; Eisenstein, I.; Munn, R. W.; Petelenz, P.

    1985-05-01

    The Fourier-transform method of calculating polarization energies is used to evaluate the energies of electron-hole pairs in anthracene, tetracene and pentacene crystals as a function of separation, r. Charge-quadrupole interactions are included which refine and extend previous calculations on anthracene. Detailed analysis of the long-range behaviour shows that the total electrostatic energy has the coulombic 1/ r dependence, mediated by an apparent dielectric constant which depends on direction, varying more weakly than the dielectric tensor itself and in the opposite sense. The calculated charge-transfer (CT) energies determine the potential for the CT eigenstates of the crystal hamiltonian. Several methods to approximate these states are discussed and a generalization of the Merrifield-Choi model is adopted for their description. It is shown that the lowest CT state is split by electron-transfer interaction between translationally equivalent molecules in the unit cell. By combining the calculated electronic eigenvalues with the expected vibrational structure of the CT states, a satisfactory assignment is obtained for all CT bands observed by Sebastian, Weiser, Peter and Bassler in the electro-absorption spectra of anthracene, tetracene and pentacene. This assignment is shown to be in qualitative agreement with the observed intensity distributions. The results of this spectroscopic analysis are compared with observed yields of optically generated charge carriers produced by isothermal dissociation of CT states. The available experimental results are shown to be consistent with the assumption that this process involves direct optical population of both electronic and vibronic CT levels, the latter relaxing vibrationally before (or independent of) their diffusive dissociation.

  18. Novel anthracene-based fluorescent sensor for selective recognition of acetate anions in protic media

    NASA Astrophysics Data System (ADS)

    Xu, Kuoxi; Kong, Huajie; Li, Qian; Song, Pan; Dai, Yanpeng; Yang, Li

    2015-02-01

    Novel 9-substituted anthracene derivatives were synthesized and characterized by IR, HRMS, 1H and 13C NMR. The fluorescence titration experiments were explored to study the interaction between the compounds and some anions, such as H2PO4-, P2O74-, F-, Cl-, Br-, I-, AcO- in H2O (0.01 M HEPES, pH = 7.4) under imitated physiological conditions. One of these compounds, bearing a phenylalaninol unit, showed specific fluorescence enhancement with acetate anion. The sensor L1 was found to present good selective fluorescence sensing ability to acetate anion through photoinduced electron-transfer mechanism in protic media.

  19. New 1,4-anthracene-9,10-dione derivatives as potential anticancer agents.

    PubMed

    Zagotto, G; Supino, R; Favini, E; Moro, S; Palumbo, M

    2000-01-01

    The amino-substituted anthracene-9,10-dione (9,10-anthraquinone) derivatives represent one of the most important classes of potential anticancer agents. To better understand the basic rules governing DNA sequence specificity, we have recently synthesized a new class of D- and L-aminoacyl-anthraquinone derivatives. We have tested these new compounds as cytotoxic agents, and we have correlated their activity with the configuration of the chiral aminoacyl moiety. Molecular modeling studies have been performed to compare the test drugs in terms of steric overlapping.

  20. Intersystem Crossing Mechanisms and Single Molecule Fluorescence: Terrylene in Anthracene Crystals

    SciTech Connect

    Kol'chenko, M.A.; Nicolet, A.; Orrit, M.; Kozankiewicz, B.

    2005-05-15

    Single molecule spectroscopy requires molecules with low triplet yields and/or short triplet lifetimes. The intersystem crossing (ISC) rate may be dramatically enhanced by the host matrix. Comparing the fluorescence intensity of single terrylene molecules in para-terphenyl, naphthalene, and anthracene crystals, we found a reduction of the saturation intensity by three orders of magnitude in the latter case. The fluorescence autocorrelation function indicates that the bottleneck state is the terrylene triplet. We propose a ping-pong mechanism between host and guest. This intermolecular ISC mechanism, which can open whenever the host triplet lies lower than the guest singlet, was overlooked in previous single molecule investigations.

  1. Effects of methyl substitutions on benz[a]anthracene derivatives-induced immunosuppression

    SciTech Connect

    Saas, P.; Bohuon, C.; Pallardy, M.

    1996-11-01

    Polycyclic aromatic-hydrocarbons are ubiquitous environmental contaminants known to be carcinogenic as well as immunosuppressive. Structure-activity studies have demonstrated that modifications in the number of methyl groups of benzanthracenic compounds lead to major changes in their biological activities such as induction of tumors. In the present study, we investigated the immunosuppressive effects of three benzanthracene derivatives differing by number or position of methyl radicals. 7,12-Dimethylbenz[a]anthracene, 12-methylbenz[a]anthracene, and 7-methylbenz[a]anthracene were tested for their ability to inhibit T-cell proliferation. For this purpose, we employed an in vitro activation model utilizing concanavalin A (ConA) or anti-CD3 monoclonal antibody (anti-CD3 mAb) to induce proliferation of murine T-lymphocytes form B6C3F1 mice. The three compounds inhibited splenocyte proliferation stimulated with anti-CD3 mAb, whereas DMBA and 12-MBA, but not 7-MBA, inhibited ConA-induced lymphoproliferation. Results concerning parameters involving interleukin-2 (IL-2) were correlated with those obtained for lymphoproliferation. IL-2 production and number of IL-2 receptors (IL-2R) per cell were inhibited by the three molecules tested, except for IL-2 production following ConA activation cells treated with 7-MBA. Only DMBA profoundly affected IL-2 responsiveness, suggesting that this compound may inhibit both G0 to G1 and G1 to S transitions of the cell cycle. Addition of exogenous cytokines such as IL-1 and IL-6 with IL-2, or L-2 alone, suggested that, for the three compounds tested, IL-1 and IL-6 production are not involved in benz[a]anthracene-induced immunosuppression. These results demonstrate that methylation at both 7 and 12 positions of the benzanthracene ring significantly enhances immunosuppression. DMBA may act on signal transduction mediated by the T-cell receptor (TCR) and the IL-2R, while this is not the case for 7-MBA and 12-MBA. 32 refs., 5 figs., 1 tab.

  2. (E)-1-(4-Meth-oxy-anthracen-1-yl)-2-phenyl-diazene.

    PubMed

    Crochet, Aurelien; Fromm, Katharina M; Kurteva, Vanya; Antonov, Liudmil

    2011-04-01

    The title compound, C(21)H(16)N(2)O, has an E-conformation about the diazene N=N bond. It is reasonably planar with the phenyl ring being inclined to the mean plane of the anthracene moiety [planar to within 0.077 (3) Å] by 6.43 (10)°. The crystal structure is stabilized by C-H⋯π and weak π-π inter-actions [centroid-centroid distances of 3.7192 (16) and 3.8382 (15) Å], leading to the formation of two-dimensional networks stacking along [001] and lying parallel to (110).

  3. Chromatographic and fluorescence spectroscopic studies of individual 7,12-dimethylbenz(a)anthracene--deoxyribonucleoside adducts

    SciTech Connect

    Moschel, R.C.; Pigott, M.A.; Costantino, N.; Dipple, A.

    1983-09-01

    Compared with standard Sephadex LH-20 column chromatography, a newly developed high pressure liquid chromatographic separation of hydrocarbon deoxyribonucleoside adducts derived from the DNA of mouse embryo cell cultures exposed to 7,12-dimethylbenz(a)anthracene (DMBA) provides markedly superior resolution. Once resolved, the fluorescence spectroscopic properties of the three major DMBA--DNA adducts indicate that the fluorescence exhibited by adducts derived from a bay region syn dihydrodiol epoxide of DMBA differs subtly from that exhibited by adducts derived from the isomeric anti dihydrodiol epoxide.

  4. Free Volume and Gas Permeation in Anthracene Maleimide-Based Polymers of Intrinsic Microporosity

    PubMed Central

    Khan, Muntazim Munir; Filiz, Volkan; Emmler, Thomas; Abetz, Volker; Koschine, Toenjes; Rätzke, Klaus; Faupel, Franz; Egger, Werner; Ravelli, Luca

    2015-01-01

    High free-volume copolymers were prepared via polycondensation with 2,3,5,6,-tetrafluoroterephthalonitrile (TFTPN) in which a portion of the 3,3,3',3'-tetramethyl-1,1'-spirobisindane (TTSBI) of PIM-1 was replaced with dibutyl anthracene maleimide (4bIII). An investigation of free volume using positron annihilation lifetime spectroscopy (PALS), and gas permeation measurements was carried out for the thin film composite copolymer membranes and compared to PIM-1. The average free volume hole size and the gas permeance of the copolymer membranes increased with decreasing TTSBI content in the copolymer. PMID:26030881

  5. Intramolecular vibrational energy redistribution in bridged azulene-anthracene compounds: ballistic energy transport through molecular chains.

    PubMed

    Schwarzer, D; Kutne, P; Schröder, C; Troe, J

    2004-07-22

    Intramolecular vibrational energy flow in excited bridged azulene-anthracene compounds is investigated by time-resolved pump-probe laser spectroscopy. The bridges consist of molecular chains and are of the type (CH(2))(m) with m up to 6 as well as (CH(2)OCH(2))(n) (n=1,2) and CH(2)SCH(2). After light absorption into the azulene S(1) band and subsequent fast internal conversion, excited molecules are formed where the vibrational energy is localized at the azulene side. The vibrational energy transfer through the molecular bridge to the anthracene side and, finally, to the surrounding medium is followed by probing the red edge of the azulene S(3) absorption band at 300 nm and/or the anthracene S(1) absorption band at 400 nm. In order to separate the time scales for intramolecular and intermolecular energy transfer, most of the experiments were performed in supercritical xenon where vibrational energy transfer to the bath is comparably slow. The intramolecular equilibration proceeds in two steps. About 15%-20% of the excitation energy leaves the azulene side within a short period of 300 fs. This component accompanies the intramolecular vibrational energy redistribution (IVR) within the azulene chromophore and it is caused by dephasing of normal modes contributing to the initial local excitation of the azulene side and extending over large parts of the molecule. Later, IVR in the whole molecule takes place transferring vibrational energy from the azulene through the bridge to the anthracene side and thereby leading to microcanonical equilibrium. The corresponding time constants tau(IVR) for short bridges increase with the chain length. For longer bridges consisting of more than three elements, however, tau(IVR) is constant at around 4-5 ps. Comparison with molecular dynamics simulations suggests that the coupling of these chains to the two chromophores limits the rate of intramolecular vibrational energy transfer. Inside the bridges the energy transport is essentially

  6. Fate of 7,12-dimethylbenz(a)anthracene in rainbow trout, Salmo gairdneri

    SciTech Connect

    Schnitz, A.R.; Squibb, K.S.; O'Connor, J.M.

    1987-07-01

    Polycyclic aromatic hydrocarbons (PAH) are contaminants of surface waters and sediments, especially near urban centers. Although aquatic biota accumulate PAHs from environmental sources, metabolism may be rapid, and biota sampled from contaminated areas often have concentrations lower than might be estimated from bioconcentration factors. In some cases PAH metabolism by aquatic biota may create reactive intermediates, some of which have been related to chronic effects in fishes. This report describes the fate and distribution of 7,12-dimethylbenz(a)anthracene (DMBA) after oral administration to rainbows trout (Salmo gairdneri). Emphasis has been placed on the disposition of DMBA among tissues and on DMBA transformation in the hepatobiliary system.

  7. Removal of Anthracene and Fluoranthene by Waxy Corn, Long Bean and Okra in Lead-Contaminated Soil.

    PubMed

    Somtrakoon, Khanitta; Chouychai, Waraporn; Lee, Hung

    2015-09-01

    The ability of waxy corn, long bean and okra to remove two polycyclic aromatic hydrocarbons (PAHs) from soil containing 0.63 mg Pb kg(-1) dry soil was assessed. The presence of Pb did not reduce the ability of these plants to remove the PAHs from soil. About 49 % of anthracene and 77 % of fluoranthene were removed from Pb-spiked or non-spiked soil, respectively, after 30 days. Among the plants, okra was the most efficient at removing anthracene and fluoranthene in the presence or absence of Pb in soil after 30 days. Pb did not affect fluoranthene removal, but stimulated the removal of anthracene, by long bean, waxy corn and okra. However, growth of long bean and waxy corn was poor in Pb-spiked soil and waxy corn plants died around 22 days after transplantation. The results show some promise in using plants to remove PAHs from soil which is also co-contaminated with Pb.

  8. Removal of Anthracene and Fluoranthene by Waxy Corn, Long Bean and Okra in Lead-Contaminated Soil.

    PubMed

    Somtrakoon, Khanitta; Chouychai, Waraporn; Lee, Hung

    2015-09-01

    The ability of waxy corn, long bean and okra to remove two polycyclic aromatic hydrocarbons (PAHs) from soil containing 0.63 mg Pb kg(-1) dry soil was assessed. The presence of Pb did not reduce the ability of these plants to remove the PAHs from soil. About 49 % of anthracene and 77 % of fluoranthene were removed from Pb-spiked or non-spiked soil, respectively, after 30 days. Among the plants, okra was the most efficient at removing anthracene and fluoranthene in the presence or absence of Pb in soil after 30 days. Pb did not affect fluoranthene removal, but stimulated the removal of anthracene, by long bean, waxy corn and okra. However, growth of long bean and waxy corn was poor in Pb-spiked soil and waxy corn plants died around 22 days after transplantation. The results show some promise in using plants to remove PAHs from soil which is also co-contaminated with Pb. PMID:26149081

  9. Confined growth of carbon nanoforms in one-dimension by fusion of anthracene rings inside the pores of MCM-41.

    PubMed

    Bosch-Navarro, Concha; Coronado, Eugenio; Martí-Gastaldo, Carlos; Amorós, Pedro

    2014-07-21

    We report a simple two-step procedure that uses anthracene, a cheap polyaromatic hydrocarbon with low melting point, as a molecular precursor to produce carbon nanoforms (CNFs). First, we describe the chemical synthesis of graphite from the fusion of anthracene rings at relatively low temperature (520 °C) followed by cyclodehydrogenation. Next, we extend this protocol to the synthesis of CNFs by confining the molecular precursor in a mesoporous host like MCM-41. The confined environment favors one-dimensional growth of CNFs with sizes controlled by the pores of the mesoporous host.

  10. A novel fluorescent cesium ion-selective optode membrane based on 15-crown-5-anthracene.

    PubMed

    Seo, Hyo Sook; Lee, Sang Hak

    2011-03-01

    An optode system based on a plasticized polymer membrane containing cesium ion-selective fluoroionophore and lipophilic anions for the determination of cesium ions has been developed. In this work, 15-crown-5 derivative including anthracene was used as a fluoroionophore. Emission intensity of the optode membrane incorporating 15-crown-5-anthracene was measured at 500 nm with excitation at 360 nm in the presence of Tris-HCl buffer solution. Under optimum experimental condition, the relative fluorescence intensity was linear with the concentration of cesium ion in the range of 1.0 × 10(-4) M to 1.0 × 10(-1) M and the detection limit was obtained 4.2 × 10(-5) M, as defined by LOD=3 × S(b)/m (where S(b)=standard deviation of blank signal and, m=slope of the calibration curve). The effect of pH of sample solution on the fluorescent response, the selectivity, response time and reproducibility of the optode membrane were also discussed. The fluorescent optode system shows a high selectivity and sensitivity for cesium ion with respect to other cations such as K(+), Na(+) and Li(+).

  11. Synthesis, characterization, optical and electrical properties of bis(phenylvinyl)anthracene-based polymers

    NASA Astrophysics Data System (ADS)

    Mansour, Nadia; Hriz, Khaled; Jaballah, Nejmeddine; Kreher, David; Majdoub, Mustapha

    2016-08-01

    A series of bis(phenylvinyl)anthracene-based polymers containing different lengths of polar ethylene glycol groups in the main chain (P1-3) were efficiently synthesized by Wittig polycondensation. These polymers are fully soluble in volatile solvents, which helped a lot to obtain high quality films. Moreover, these semi-conducting materials exhibited semi-crystalline morphology with relatively high glass transition temperature. In this article, the UV-visible absorption and fluorescence properties of P1-3 were studied consequently both in solution and as thin solid film: tan absorption-onset at 433 nm was observed and all these bis(phenylvinyl)anthracene-based polymers (P1-3) show a blue emission in solution, fluorescence quantum efficiencies being respectively 52% for P1, 75% for P2 and 67% for P3. In addition, the HOMO/LUMO energy levels were evaluated by cyclic voltammetry measurements and indicate a p-type semi-conducting materials. Finally, the electrical properties of P1-3 were investigated by recording current-tension characteristics and these experimental results were modeled by the current space-charge-limited (SCLC) mechanism.

  12. ATRAZINE INCREASES DIMETHYLBENZ[A]ANTHRACENE-INDUCED MAMMARY TUMOR INCIDENCE IN LONG EVANS OFFSPRING EXPOSED IN UTERO

    EPA Science Inventory

    ATRAZINE INCREASES DIMETHYLBENZ[A]ANTHRACENE-INDUCED MAMMARY TUMOR INCIDENCE IN LONG EVANS OFFSPRING EXPOSED IN UTERO.

    SE Fenton and CC Davis

    Reproductive Toxicology Division, NHEERL, ORD, USEPA, Durham, NC, USA

    Recently, we found that ATR exposure during ma...

  13. Formation and Stabilization of Environmentally Persistent Free Radicals Induced by the Interaction of Anthracene with Fe(III)-Modified Clays.

    PubMed

    Jia, Hanzhong; Nulaji, Gulimire; Gao, Hongwei; Wang, Fu; Zhu, Yunqing; Wang, Chuanyi

    2016-06-21

    Environmentally persistent free radicals (EPFRs) are occasionally detected in Superfund sites but the formation of EPFRs induced by polycyclic aromatic hydrocarbons (PAHs) is not well understood. In the present work, the formation of EPFRs on anthracene-contaminated clay minerals was quantitatively monitored via electron paramagnetic resonance (EPR) spectroscopy, and surface/interface-related environmental influential factors were systematically explored. The obtained results suggest that EPFRs are more readily formed on anthracene-contaminated Fe(III)-montmorillonite than in other tested systems. Depending on the reaction condition, more than one type of organic radicals including anthracene-based radical cations with g-factors of 2.0028-2.0030 and oxygenic carbon-centered radicals featured by g-factors of 2.0032-2.0038 were identified. The formed EPFRs are stabilized by their interaction with interlayer surfaces, and such surface-bound EPFRs exhibit slow decay with 1/e-lifetime of 38.46 days. Transformation pathway and possible mechanism are proposed on the basis of experimental results and quantum mechanical simulations. Overall, the formation of EPFRs involves single-electron-transfer from anthracene to Fe(III) initially, followed by H2O addition on formed aromatic radical cation. Because of their potential exposure in soil and atmosphere, such clay surface-associated EPFRs might induce more serious toxicity than PAHs and exerts significant impacts on human health.

  14. Coordination Complexes as Catalysts: The Oxidation of Anthracene by Hydrogen Peroxide in the Presence of VO(acac)[subscript 2

    ERIC Educational Resources Information Center

    Charleton, Kimberly D. M.; Prokopchuk, Ernest M.

    2011-01-01

    A laboratory experiment aimed at students who are studying coordination chemistry of transition-metal complexes is described. A simple vanadyl acetylacetonate complex can be used as a catalyst in the hydrogen peroxide oxidation of anthracene to produce anthraquinone. The reaction can be performed under a variety of reaction conditions, ideally by…

  15. Estrogenic status modulates the effect of soy on hepatic responses to 7,12- dimethylbenz(a)anthracene

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We examined the influence of estradiol (E2) status and soy protein isolate (SPI) intake on the hepatic responses altered by 7,12-dimethylbenz(a)anthracene (DMBA, a polycyclic aromatic hydrocarbon [PAH]). Sprague-Dawley rats were ovariectomized (OVX) at PND50 and infused with E2 or vehicle for 14d an...

  16. Estrogenic status modulates the effect of soy on hepatic responses to 7,12-dimethylbenz(a)anthracene (DMBA)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We examined the influence of estradiol (E2) status and soy protein isolate (SPI) intake on the hepatic responses altered by 7,12-dimethylbenz(a)anthracene (DMBA, a polycyclic aromatic hydrocarbon [PAH]). Sprague–Dawley rats were ovariectomized (OVX) at PND50 and infused with E2 or vehicle for 14 d a...

  17. Molecular self-healing mechanisms between C60-fullerene and anthracene unveiled by Raman and two-dimensional correlation spectroscopy.

    PubMed

    Geitner, R; Kötteritzsch, J; Siegmann, M; Fritzsch, R; Bocklitz, T W; Hager, M D; Schubert, U S; Gräfe, S; Dietzek, B; Schmitt, M; Popp, J

    2016-07-21

    The self-healing polymer P(LMA-co-MeAMMA) crosslinked with C60-fullerene has been studied by FT-Raman spectroscopy in combination with two-dimensional (2D) correlation analysis and density functional theory calculations. To unveil the molecular changes during the self-healing process mediated by the Diels-Alder equilibrium between 10-methyl-9-anthracenyl groups and C60-fullerene different anthracene-C60-fullerene adducts have been synthesized and characterized by time-, concentration- and temperature-dependent FT-Raman measurements. The self-healing process could be monitored via the C60-fullerene vibrations at 270, 432 and 1469 cm(-1). Furthermore, the detailed analysis of the concentration-dependent FT-Raman spectra point towards the formation of anthracene-C60-fullerene adducts with an unusual high amount of anthracene bound to C60-fullerene in the polymer film, while the 2D correlation analysis of the temperature-dependent Raman spectra suggests a stepwise dissociation of anthracene-C60-fullerene adducts, which are responsible for the self-healing of the polymer. PMID:27327116

  18. Quinoline-Substituted 10-(naphthalene-7-yl)anthracene Derivatives for Blue Fluorescent Organic Light-Emitting Diodes.

    PubMed

    Kim, Chanwoo; Park, Soo Na; Lee, Seul Bee; Kim, Young Seok; Lee, Ho Won; Kim, Young Kwan; Yoon, Seung Soo

    2016-02-01

    In this study, we have designed and synthesized blue emitters based on quinoline-substituted 10-(naphthalene-7-yl)anthracene. Particularly, a material exhibited highly efficient blue electroluminescence with CIE coordinates of (0.15, 0.18). PMID:27433688

  19. Multiple DNA Extractions Coupled with Stable-Isotope Probing of Anthracene-Degrading Bacteria in Contaminated Soil▿†

    PubMed Central

    Jones, Maiysha D.; Singleton, David R.; Sun, Wei; Aitken, Michael D.

    2011-01-01

    In many of the DNA-based stable-isotope probing (SIP) studies published to date in which soil communities were investigated, a single DNA extraction was performed on the soil sample, usually using a commercial DNA extraction kit, prior to recovering the 13C-labeled (heavy) DNA by density-gradient ultracentrifugation. Recent evidence suggests, however, that a single extraction of a soil sample may not lead to representative recovery of DNA from all of the organisms in the sample. To determine whether multiple DNA extractions would affect the DNA yield, the eubacterial 16S rRNA gene copy number, or the identification of anthracene-degrading bacteria, we performed seven successive DNA extractions on the same aliquot of contaminated soil either untreated or enriched with [U-13C]anthracene. Multiple extractions were necessary to maximize the DNA yield and 16S rRNA gene copy number from both untreated and anthracene-enriched soil samples. Sequences within the order Sphingomonadales, but unrelated to any previously described genus, dominated the 16S rRNA gene clone libraries derived from 13C-enriched DNA and were designated “anthracene group 1.” Sequences clustering with Variovorax spp., which were also highly represented, and sequences related to the genus Pigmentiphaga were newly associated with anthracene degradation. The bacterial groups collectively identified across all seven extracts were all recovered in the first extract, although quantitative PCR analysis of SIP-identified groups revealed quantitative differences in extraction patterns. These results suggest that performing multiple DNA extractions on soil samples improves the extractable DNA yield and the number of quantifiable eubacterial 16S rRNA gene copies but have little qualitative effect on the identification of the bacterial groups associated with the degradation of a given carbon source by SIP. PMID:21398486

  20. Growth of large naphthalene and anthracene single-crystal sheets at the liquid–air interface

    SciTech Connect

    Postnikov, V. A.; Chertopalov, S. V.

    2015-07-15

    The growth of organic single crystals of naphthalene (C{sub 10}H{sub 8}) and anthracene (C{sub 14}H{sub 10}) at the liquid‒air interface from a mixture of solvents has been investigated. The growth technique used in the study makes it possible to obtain single-crystal sheets up to 10 mm in size for 24 h. The surface morphology and structure of the crystals have been analyzed by optical microscopy and X-ray diffraction. C{sub 10}H{sub 8} and C{sub 14}H{sub 10} single crystals grow coplanarly along the (001) plane. A thermodynamic model of the flat-crystal nucleus formation at the liquid‒air interface, based on the analysis of the change in the free Gibbs energy, is considered.

  1. Electronic and vibrational spectra of matrix isolated anthracene radical cations - Experimental and theoretical aspects

    NASA Technical Reports Server (NTRS)

    Szczepanski, Jan; Vala, Martin; Talbi, Dahbia; Parisel, Olivier; Ellinger, Yves

    1993-01-01

    The IR vibrational and visible/UV electronic absorption spectra of the anthracene cation, An(+), were studied experimentally, in argon matrices at 12 K, as well as theoretically, using ab initio calculations for the vibrational modes and enhanced semiempirical methods with configuration interaction for the electronic spectra. It was found that both approaches predicted well the observed photoelectron spectrum. The theoretical IR intensities showed some remarkable differences between neutral and ionized species (for example, the CH in-plane bending modes and CC in-plane stretching vibrations were predicted to increase by several orders of magnitude upon ionization). Likewise, estimated experimental IR intensities showed a significant increase in the cation band intensities over the neutrals. The implication of these findings for the hypothesis that polycyclic aromatic hydrocarbon cations are responsible for the unidentified IR emission bands from interstellar space is discussed.

  2. NAH plasmid-mediated catabolism of anthracene and phenanthrene to naphthoic acids.

    PubMed Central

    Menn, F M; Applegate, B M; Sayler, G S

    1993-01-01

    Pseudomonas fluorescens 5R contains an NAH7-like plasmid (pKA1), and P. fluorescens 5R mutant 5RL contains a bioluminescent reporter plasmid (pUTK21) which was constructed by transposon mutagenesis. Polymerase chain reaction mapping confirmed the localization of lux transposon Tn4431 300 bp downstream from the start of the nahG gene. Two degradation products, 2-hydroxy-3-naphthoic acid and 1-hydroxy-2-naphthoic acid, were recovered and identified from P. fluorescens 5RL as biochemical metabolites from the biotransformation of anthracene and phenanthrene, respectively. This is the first report which provides direct biochemical evidence that the naphthalene plasmid degradative enzyme system is involved in the degradation of higher-molecular-weight polycyclic aromatic hydrocarbons other than naphthalene. Images PMID:8328810

  3. Novel thiophene derivatives with sulfonamide, isoxazole, benzothiazole, quinoline and anthracene moieties as potential anticancer agents.

    PubMed

    Ghorab, Mostafa M; Bashandy, Mahmoud S; Alsaid, Mansour S

    2014-12-01

    A novel series of thiophenes having biologically active sulfonamide 2-11, 3-methylisoxazole 12, 4-methoxybenzo[d] thiazole 13, quinoline 14, 15, benzoylphenylamino 16, and anthracene-9,10-dione 17 moieties were prepared. Structures of the newly synthesized compounds were established by elemental analysis and spectral data. All newly synthesized compounds were evaluated for their in vitro anticancer activity against human breast cancer cell line (MCF7). Most of the screened compounds showed cytotoxic activities compared to doxorubicin as a positive control. Compounds 6, 7, 9 and 13 (IC50 values 10.25, 9.70, 9.55 and 9.39 μmol L-1) revealed higher cytotoxic activities than that of doxorubicin (IC50 = 32.00 μmol L-1). Also, compounds 5, 8 and 10 were found nearly as active as doxorubicin (IC50 28.85, 23.48 and 27.51 μmol L-1).

  4. Investigations of preferential solvation on 1,4-dimethoxy-3-methyl anthracene-9,10-dione.

    PubMed

    Umadevi, M; Kumari, M Vadana; Bharathi, M Suthandera; Vanelle, P; Terme, T

    2011-01-01

    Preferential solvation of 1,4-dimethoxy-3-methyl anthracene-9,10-dione (DMMAD) has been investigated using optical absorption technique. The preferential solvation parameters show that the DMMAD is preferentially solvated by acetone in acetone (AC)+propan-2-ol (PROH), AC+CH2Cl2 and AC+CCl4 mixtures. DMMAD prefers PROH in PROH+CCl4 mixture. In the case of benzene+CCl4 mixture DMMAD is preferentially solvated by benzene in benzene rich region and by CCl4 in CCl4 rich region. The results have been discussed in terms of hydrogen bonding, dipole-dipole and induced dipole-dipole interactions between DMMAD and solvent molecules.

  5. Diazaquinomycins E–G, Novel Diaza-Anthracene Analogs from a Marine-Derived Streptomyces sp.

    PubMed Central

    Mullowney, Michael W.; Ó hAinmhire, Eoghainín; Shaikh, Anam; Wei, Xiaomei; Tanouye, Urszula; Santarsiero, Bernard D.; Burdette, Joanna E.; Murphy, Brian T.

    2014-01-01

    As part of our program to identify novel secondary metabolites that target drug-resistant ovarian cancers, a screening of our aquatic-derived actinomycete fraction library against a cisplatin-resistant ovarian cancer cell line (OVCAR5) led to the isolation of novel diaza-anthracene antibiotic diazaquinomycin E (DAQE; 1), the isomeric mixture of diazaquinomycin F (DAQF; 2) and diazaquinomycin G (DAQG; 3), and known analog diazaquinomycin A (DAQA; 4). The structures of DAQF and DAQG were solved through deconvolution of X-Ray diffraction data of their corresponding co-crystal. DAQE and DAQA exhibited moderate LC50 values against OVCAR5 of 9.0 and 8.8 μM, respectively. At lethal concentrations of DAQA, evidence of DNA damage was observed via induction of apoptosis through cleaved-PARP. Herein, we will discuss the isolation, structure elucidation, and biological activity of these secondary metabolites. PMID:24921978

  6. Polymorphism in Self-Assembled Structures of 9-Anthracene Carboxylic Acid on Ag(111)

    PubMed Central

    Lu, Chao; Wei, Yinying; Zhu, Erkuang; Reutt-Robey, Janice E.; Xu, Bo

    2012-01-01

    Surface self-assembly process of 9-anthracene carboxylic acid (AnCA) on Ag(111) was investigated using STM. Depending on the molecular surface density, four spontaneously formed and one annealed AnCA ordered phases were observed, namely a straight belt phase, a zigzag double-belt phase, two simpler dimer phases, and a kagome phase. The two high-density belt phases possess large unit cells on the scale length of 10 nm, which are seldom observed in molecular self-assembled structures. This structural diversity stems from a complicated competition of different interactions of AnCA molecules on metal surface, including intermolecular and molecular-substrate interactions, as well as the steric demand from high molecular surface density. PMID:22837666

  7. Novel anthracene-based fluorescent sensor for selective recognition of acetate anions in protic media.

    PubMed

    Xu, Kuoxi; Kong, Huajie; Li, Qian; Song, Pan; Dai, Yanpeng; Yang, Li

    2015-02-25

    Novel 9-substituted anthracene derivatives were synthesized and characterized by IR, HRMS, (1)H and (13)C NMR. The fluorescence titration experiments were explored to study the interaction between the compounds and some anions, such as H2PO4(-), P2O7(4-), F(-), Cl(-), Br(-), I(-), AcO(-) in H2O (0.01 M HEPES, pH=7.4) under imitated physiological conditions. One of these compounds, bearing a phenylalaninol unit, showed specific fluorescence enhancement with acetate anion. The sensor L1 was found to present good selective fluorescence sensing ability to acetate anion through photoinduced electron-transfer mechanism in protic media. PMID:25282025

  8. Intramolecular Charge-Transfer Interaction of Donor-Acceptor-Donor Arrays Based on Anthracene Bisimide.

    PubMed

    Iwanaga, Tetsuo; Ogawa, Marina; Yamauchi, Tomokazu; Toyota, Shinji

    2016-05-20

    We designed anthracene bisimide (ABI) derivatives having two triphenylamine (TPA) groups as donor units at the 9,10-positions to form a novel π-conjugated donor-acceptor system. These compounds and their analogues with ethynylene linkers were synthesized by Suzuki-Miyaura and Sonogashira coupling reactions, respectively. In UV-vis spectra, the linker-free derivatives showed broad absorption bands arising from intramolecular charge-transfer interactions. Introducing ethynylene linkers resulted in a considerable red shift of the absorption bands. In fluorescence spectra, the ethynylene derivatives showed intense emission bands at 600-650 nm. Their photophysical and electrochemical properties were compared with those of the corresponding mono TPA derivatives on the basis of theoretical calculations and cyclic voltammetry to evaluate the intramolecular electronic interactions between the donor and acceptor units.

  9. Identification of 7,12-dimethylbenz[a]anthracene metabolites that lead to mutagenesis in mammalian cells

    PubMed Central

    Huberman, Eliezer; Chou, Ming W.; Yang, Shen K.

    1979-01-01

    The mutagenicity of 7,12-dimethylbenz[a]-anthracene (DMBA) and 11 of its enzymatically derived metabolites was tested with Chinese hamster V79 cells for identification of mutagenic metabolites. The metabolites consisted of 7-hydroxymethyl-12-methylbenz[a]anthracene, 7-methyl-12-hydroxymethylbenz[a]anthracene, 7,12-dihydroxymethylbenz[a]anthracene, three trans-3,4-diols, two trans-5,6-diols, and three trans-8,9-diols, all of which derived from DMBA or from the hydroxymethyl derivatives. Mutations were characterized by resistance to ouabain and 6-thioguanine. None of the tested metabolites were mutagenic in V79 cells, which do not metabolize polycyclic aromatic hydrocarbons. Therefore, mutagenesis in the V79 cells was tested in the presence of golden hamster cells capable of metabolizing polycyclic aromatic hydrocarbons (cell-mediated assay). In this assay, DMBA, 7-hydroxymethyl-12-methylbenz[a]anthracene, 7-methyl-12-hydroxymethylbenz[a]anthracene, and their trans3,4-diols were mutagenic for both genetic markers, and the mutagenic response increased as a function of the hydrocarbon dose. All other metabolites were either inactive or showed up to a 4-fold higher mutation frequency than the untreated V79 cells for ouabain and 6-thioguanine resistance. The DMBA-trans-3,4-diol was the only metabolite that was more active than DMBA itself; at 0.05 μM it was 6-8 times more active than DMBA itself; at 0.05 μM it was 6-8 times more active than DMBA in inducing both ouabain and 6-thioguanine resistance. This diol was mutagenic at a dose as low as 0.01 μM. Mutagenesis by DMBA and the trans-3,4-diols was inhibited by 7,8-benzoflavone, an inhibitor of mixed-function oxidases. Analysis of DMBA metabolism in intact golden hamster cells indicated that DMBA-trans-3,4-diol is one of the major metabolites produced. Our results therefore suggest that DMBA-trans-3,4-diol may be metabolized to a diol-epoxide, presumably the trans-3,4-diol-1,2-epoxide, which may be a major reactive

  10. Raman and surface enhanced Raman scattering study of the orientation of cruciform 9,10-anthracene thiophene and furan derivatives deposited on a gold colloidal surface

    NASA Astrophysics Data System (ADS)

    Muñoz-Pérez, J.; Leyton, P.; Paipa, C.; Soto, J. P.; Brunet, J.; Gómez-Jeria, J. S.; Campos-Vallette, M. M.

    2016-10-01

    The 9,10-di(thiophen-2-yl)anthracene (TAT), 9,10-di(furan-2-yl)anthracene (FAF) and 2-[(10-(thiophen-2-yl)anthracen-9-yl)]furan (TAF) cruciform molecular systems were synthesized using one-step coupling reactions and structurally characterized via Raman, infrared, 1H NMR, 13C NMR and mass spectroscopies. The orientation of the analytes on a gold colloidal surface was inferred from a surface-enhanced Raman scattering (SERS) study. The metal surface interaction was driven by the S and O atoms of the thiophene and furan α-substituents, and the plane of the anthracene fragment remained parallel to the surface. Theoretical calculations based on a simplified molecular model for the analyte-surface interaction provide a good representation of the experimental data.

  11. Design of Poly(L-lactide)-Poly(ethylene glycol) Copolymer with Light-Induced Shape-Memory Effect Triggered by Pendant Anthracene Groups.

    PubMed

    Xie, Hui; He, Man-jie; Deng, Xiao-Ying; Du, Lan; Fan, Cheng-Jie; Yang, Ke-Ke; Wang, Yu-Zhong

    2016-04-13

    A novel light-induced shape-memory material based on poly(l-lactide)-poly(ethylene glycol) copolymer is developed successfully by dangling the photoresponsive anthracene group on the PEG soft segment selectively. For synthesis strategy, the preprepared photoresponsive monomer N,N-bis(2-hydroxyethyl)-9-anthracene-methanamine (BHEAA) is first embedded into PEG chains; then, we couple this anthracene-functionalized PEG precursor with PLA precursor to result in PLA-PEG-A copolymer. The composition of target product can be well-defined by simply adjusting the feed ratio. The chemical structures of intermediate and final products are confirmed by (1)H NMR. Differential scanning calorimetry analysis of material reveals that the PEG soft segment became noncrystallizable when 4% or more BHEAA is introduced, and this feature is beneficial to the mobility of anthracene groups in polymer matrix. The static tensile tests show that the samples exhibit rubberlike mechanical properties except for the PLA-dominant one. The reversibility of [4 + 4] cycloaddition reaction between pendant anthracene groups in PLA-PEG-A film is demonstrated by UV-vis. Eventually, the light-induced shape-memory effect (LSME) is successfully realized in PLA-PEG-A. The results of cyclic photomechanical tests also reveal that the content of PLA hard segment as well as photosensitive anthracene moieties plays a crucial role in LSME. PMID:27031590

  12. Anthraphane: An Anthracene-Based, Propeller-Shaped D(3h)-Symmetric Hydrocarbon Cyclophane and Its Layered Single Crystal Structures.

    PubMed

    Servalli, Marco; Trapp, Nils; Wörle, Michael; Klärner, Frank-Gerrit

    2016-03-18

    The novel hydrocarbon propeller-shaped D3h-symmetric cyclophane (3), "anthraphane", was prepared through a revisited and optimized gram-scale synthesis of the key building block anthracene-1,8-ditriflate 7. Anthraphane has a high tendency to crystallize and single crystals in size ranges of 100-200 μm are easily obtained from different solvents. The crystallization behavior of 3 was extensively studied to unravel packing motifs and determine whether the packing can be steered into a desired direction, so to allow topochemical photopolymerization. SC-XRD shows that anthraphane packs in layers irrespective of the solvent used for crystallization. However, within the layers, intermolecular arrangements and π-π interactions of the anthracene units vary strongly. Four interaction motifs for the anthracene moieties are observed and discussed in detail: two types of exclusively edge-to-face (etf), a mixture of edge-to-face and face-to-face (ftf), and no anthracene-anthracene interaction at all. To elucidate why an exclusive ftf stacking was not observed, electrostatic potential surface (EPS) calculations with the semiempirical PM3 method were performed. They show qualitatively that the anthracene faces bear a strong negative surface potential, which may be the cause for this cyclophane to avoid ftf interactions. This combined crystallographic and computational study provides valuable insights on how to create all-ftf packings.

  13. Design of Poly(L-lactide)-Poly(ethylene glycol) Copolymer with Light-Induced Shape-Memory Effect Triggered by Pendant Anthracene Groups.

    PubMed

    Xie, Hui; He, Man-jie; Deng, Xiao-Ying; Du, Lan; Fan, Cheng-Jie; Yang, Ke-Ke; Wang, Yu-Zhong

    2016-04-13

    A novel light-induced shape-memory material based on poly(l-lactide)-poly(ethylene glycol) copolymer is developed successfully by dangling the photoresponsive anthracene group on the PEG soft segment selectively. For synthesis strategy, the preprepared photoresponsive monomer N,N-bis(2-hydroxyethyl)-9-anthracene-methanamine (BHEAA) is first embedded into PEG chains; then, we couple this anthracene-functionalized PEG precursor with PLA precursor to result in PLA-PEG-A copolymer. The composition of target product can be well-defined by simply adjusting the feed ratio. The chemical structures of intermediate and final products are confirmed by (1)H NMR. Differential scanning calorimetry analysis of material reveals that the PEG soft segment became noncrystallizable when 4% or more BHEAA is introduced, and this feature is beneficial to the mobility of anthracene groups in polymer matrix. The static tensile tests show that the samples exhibit rubberlike mechanical properties except for the PLA-dominant one. The reversibility of [4 + 4] cycloaddition reaction between pendant anthracene groups in PLA-PEG-A film is demonstrated by UV-vis. Eventually, the light-induced shape-memory effect (LSME) is successfully realized in PLA-PEG-A. The results of cyclic photomechanical tests also reveal that the content of PLA hard segment as well as photosensitive anthracene moieties plays a crucial role in LSME.

  14. Rapid growth of thin and flexible organic semiconductor single crystal Anthracene by solution growth technique for device fabrication

    NASA Astrophysics Data System (ADS)

    Thirupugalmani, K.; Shanmugam, G.; Kannan, V.; Brahadeeswaran, S.

    2015-03-01

    Growth of thin and flexible organic semiconductor crystal Anthracene (AN) has been achieved in a very short duration. This simple, yet an effective approach was serendipitously found to yield high quality crystal with typical dimensions of 22×23×0.15-0.50 mm3 within a duration of about 30 min whereas a conventional method could take about 7-10 days to achieve similar dimensions. Further, these crystals were seen swirling and settling down slowly at the bottom of the growth flask. These factors were favorably utilized to place the Anthracene crystals firmly on prefabricated flexible substrates when they were kept in different heights within the solutions. This systematic approach also facilitated the fabrication of organic field effect transistor (OFET) and the results obtained were encouraging.

  15. Pathway-Dependent Post-assembly Modification of an Anthracene-Edged M(II)4L6 Tetrahedron.

    PubMed

    Ronson, Tanya K; Pilgrim, Ben S; Nitschke, Jonathan R

    2016-08-24

    Fe(II)4L6 tetrahedral cage 1 undergoes post-assembly modification (PAM) via a Diels-Alder cycloaddition of the anthracene panels of the cage with tetracyanoethylene (TCNE). The modified cage 2 possesses an enclosed cavity suitable for encapsulation of the fullerene C60, whereas original cage 1 forms a unique covalent adduct through a Diels-Alder cycloaddition of three of its anthracene ligands with C60. This adduct undergoes further PAM via reaction of the remaining three ligands with TCNE, enabling the isolation of two distinct products depending on the order of addition of C60 and TCNE. Modified cage 2 was also able to bind an anionic guest, [Co(C2B9H11)2](-), which was not encapsulated by the original cage, demonstrating the potential of PAM for tuning the binding properties of supramolecular hosts.

  16. Sterilization affects soil organic matter chemistry and bioaccumulation of spiked p,p'-DDE and anthracene by earthworms.

    PubMed

    Kelsey, Jason W; Slizovskiy, Ilya B; Peters, Richard D; Melnick, Adam M

    2010-06-01

    Laboratory experiments were conducted to assess the effects of soil sterilization on the bioavailability of spiked p,p'-DDE and anthracene to the earthworms Eisenia fetida and Lumbricus terrestris. Physical and chemical changes to soil organic matter (SOM) induced by sterilization were also studied. Uptake of both compounds added after soil was autoclaved or gamma irradiated increased for E. fetida. Sterilization had no effect on bioaccumulation of p,p'-DDE by L. terrestris, and anthracene uptake increased only in gamma-irradiated soils. Analyses by FT-IR and DSC indicate sterilization alters SOM chemistry and may reduce pollutant sorption. Chemical changes to SOM were tentatively linked to changes in bioaccumulation, although the effects were compound and species specific. Artifacts produced by sterilization could lead to inaccurate risk assessments of contaminated sites if assumptions derived from studies carried out in sterilized soil are used. Ultimately, knowledge of SOM chemistry could aid predictions of bioaccumulation of organic pollutants. PMID:20227150

  17. Effect of torsional twist on 2nd order non-linear optical activity of anthracene and pyrene tricyanofuran derivatives.

    PubMed

    Planells, Miquel; Pizzotti, Maddalena; Nichol, Gary S; Tessore, Francesca; Robertson, Neil

    2014-11-14

    Tricyanofuran (TCF) derivatives attached to both anthracene and pyrene moieties were synthesised and characterised by optical, electrochemical and computational techniques. Both compounds exhibited similar absorption profile as well as electrochemical behaviour, however the pyrene derivative showed 20-fold higher non-linear optical activity measured by the EFISH technique. This huge difference has been assigned to (i) a lower molar absorption and (ii) a higher torsion angle for the anthracene derivative, confirmed by both experimental X-ray diffraction and DFT calculations. Furthermore, we note that the μβ1.907 value of -1700 × 10(-48) esu recorded for the pyrene derivative in CHCl3/pyridine is remarkable for a NLO chromophore lacking a classical push-pull structure. PMID:25264846

  18. Pathway-Dependent Post-assembly Modification of an Anthracene-Edged M(II)4L6 Tetrahedron.

    PubMed

    Ronson, Tanya K; Pilgrim, Ben S; Nitschke, Jonathan R

    2016-08-24

    Fe(II)4L6 tetrahedral cage 1 undergoes post-assembly modification (PAM) via a Diels-Alder cycloaddition of the anthracene panels of the cage with tetracyanoethylene (TCNE). The modified cage 2 possesses an enclosed cavity suitable for encapsulation of the fullerene C60, whereas original cage 1 forms a unique covalent adduct through a Diels-Alder cycloaddition of three of its anthracene ligands with C60. This adduct undergoes further PAM via reaction of the remaining three ligands with TCNE, enabling the isolation of two distinct products depending on the order of addition of C60 and TCNE. Modified cage 2 was also able to bind an anionic guest, [Co(C2B9H11)2](-), which was not encapsulated by the original cage, demonstrating the potential of PAM for tuning the binding properties of supramolecular hosts. PMID:27500974

  19. A comparative approach to 7, 12-dimethylbenz[a]anthracene effects: Metabolism and mutagenesis in mice and fish

    SciTech Connect

    Gallagher, K.; Cline, J.; Burkhart, J.G.; Gundersen, J.L.

    1997-10-01

    A comparative approach was used to examine the effects of exposure to the potent carcinogen 7,12-dimethylbenz[a]anthracene (DMBA) in two divergent sentinel species, mouse and fish, containing a common transgenic reporter, the bacteriophage {O}X174am3. Effects of DMBA were examined using both in vitro and in vivo studies through the analysis of metabolites, cytochrome P450 was examined 72 hours after DMBA dosing using an assay for 7-ethoxyresorufin-o-deethylase (EROD) activity. Fish showed an increasing trend of EROD induction with increasing dose, with the EROD level at the highest dose being significantly greater than corn oil controls and the lowest DMBA dose. DMBA had less of an effect on mouse P450 levels. Metabolites of DMBA in the bile at 12 hours were quantified in both species using HPLC/PDA detection. Bile extracts were enzyme digested to differentiate glucuronide, sulfate and glutathione conjugates. Primary metabolites in mice were 2-hydroxy-7,12-dimethylbenz[a]anthracene, 7-hydroxymethyl-12-methylbenz[a]anthracene. The same metabolites were detected in the fish with the addition of 7,12-bis-hydrodxymethylbenz[a]anthracene. In vitro assays using uninduced and 3-methylcholanthrene-induced mouse microsomes showed no increase over background mutant frequencies of 1-3x10{sup -6} when 0X DNA was incubated with DMBA. In vivo induced mutation was also examined in mice and fish liver. The 1.9 and 19 mg/kg doses of DMBA resulted in a 10-fold increase in mutation frequency over controls in fish. There was a similar increase in mutation frequency at the 19 mg/kg dose in mice. Analysis of the 1.9 mb/kg dosed mice and the replicate variance among treated and control animals is underway.

  20. Vibrational properties of organic donor-acceptor molecular crystals: Anthracene-pyromellitic-dianhydride (PMDA) as a case study

    SciTech Connect

    Fonari, A.; Corbin, N. S.; Coropceanu, V. E-mail: coropceanu@gatech.edu; Vermeulen, D.; McNeil, L. E.; Goetz, K. P.; Jurchescu, O. D.; Bredas, J. L. E-mail: coropceanu@gatech.edu

    2015-12-14

    We establish a reliable quantum-mechanical approach to evaluate the vibrational properties of donor-acceptor molecular crystals. The anthracene-PMDA (PMDA = pyromellitic dianhydride) crystal, where anthracene acts as the electron donor and PMDA as the electron acceptor, is taken as a representative system for which experimental non-resonance Raman spectra are also reported. We first investigate the impact that the amount of nonlocal Hartree-Fock exchange (HFE) included in a hybrid density functional has on the geometry, normal vibrational modes, electronic coupling, and electron-vibrational (phonon) couplings. The comparison between experimental and theoretical Raman spectra indicates that the results based on the αPBE functional with 25%-35% HFE are in better agreement with the experimental results compared to those obtained with the pure PBE functional. Then, taking αPBE with 25% HFE, we assign the vibrational modes and examine their contributions to the relaxation energy related to the nonlocal electron-vibration interactions. The results show that the largest contribution (about 90%) is due to electron interactions with low-frequency vibrational modes. The relaxation energy in anthracene-PMDA is found to be about five times smaller than the electronic coupling.

  1. Synthesis and calculated properties of some 1,4-bis(amino)anthracene-9,10-diones.

    PubMed

    Morley, John O; Furlong, Patrick J

    2006-11-01

    The synthesis of a number of 1,4-bis(amino)anthracene-9,10-diones containing chlorine or sulfur which are related to the anti-cancer drugs Ametantrone and Mitoxantrone are reported. 1,4-Dichloro-2,3-dihydro-5,8-dihydroxyanthracene-9,10-dione reacts readily with a series of alkylamines to yield the corresponding 1,4-bis(alkylamino)-5,8-dichloroanthracene-9,10-dione after oxidation. The subsequent reaction of the products with ethanethiol or thiophenol gives the corresponding 1,4-bis(alkylamino)-5,8-bis(sulfanyl)anthracene-9,10-dione in good yield. Theoretical calculations at the RHF 6-31G** level indicate that the introduction of either chlorine or the phenylsulfanyl group into the 5- and 8-positions of 1,4-bis(alkylamino)anthracene-9,10-diones results in a lowering of the LUMO energies suggesting that related functionalised derivatives might have lower cardiotoxicities than Mitoxantrone.

  2. Toxicity of benz(a)anthracene and fluoranthene to marine phytoplankton in culture: does cell size really matter?

    PubMed

    Ben Othman, Hiba; Leboulanger, Christophe; Le Floc'h, Emilie; Mabrouk, Hassine Hadj; Hlaili, Asma Sakka

    2012-12-01

    The toxicity of benz(a)anthracene and fluoranthene (polycyclic aromatic hydrocarbons, PAHs) was evaluated on seven species of marine algae in culture belonging to pico-, nano-, and microphytoplankton, exposed to increasing concentrations of up to 2 mg L(-1). The short-term (24h) toxicity was assessed using chlorophyll a fluorescence transients, linked to photosynthetic parameters. The maximum quantum yield Fv/Fm was lower at the highest concentrations tested and the toxicity thresholds were species-dependent. For acute effects, fluoranthene was more toxic than benz(a)anthracene, with LOECs of 50.6 and 186 μg L(-1), respectively. After 72 h exposure, there was a dose-dependent decrease in cell density, fluoranthene being more toxic than benz(a)anthracene. The population endpoint at 72 h was affected to a greater extent than the photosynthetic endpoint at 24h. EC50 was evaluated using the Hill model, and species sensitivity was negatively correlated to cell biovolume. The largest species tested, the dinoflagellate Alexandrium catenella, was almost insensitive to either PAH. The population endpoint EC50s for fluoranthene varied from 54 μg L(-1) for the picophytoplankton Picochlorum sp. to 418 μg L(-1) for the larger diatom Chaetoceros muelleri. The size/sensitivity relationship is proposed as a useful model when there is a lack of ecotoxicological data on hazardous chemicals, especially in marine microorganisms. PMID:23122731

  3. Self-Assembly of Amphiphilic Anthracene-Functionalized β-Cyclodextrin (CD-AN) through Multi-Micelle Aggregation.

    PubMed

    Zhang, Yuannan; Xu, Hongjie; Ma, Xiaodong; Shi, Zixing; Yin, Jie; Jiang, Xuesong

    2016-06-01

    Multi-micelle aggregation (MMA) mechanism is widely acknowledged to explicate large spherical micelles self-assembly, but the process of MMA during self-assembly is hard to observe. Herein, a novel kind of strong, regular microspheres fabricated from self-assembly of amphiphilic anthracene-functionalized β-cyclodextrin (CD-AN) via Cu(I)-catalyzed azide-alkyne click reactions is reported. The obtained CD-AN amphiphiles can self-assemble in water from primary core-shell micelles to secondary aggregates with the diameter changing from several tens nm to around 600-700 nm via MMA process according to the images of scanning electron microscopy, transmission electron microscopy, and atomic force microscopy as well as the dynamic light scattering measurements, followed by further crosslinking through photo-dimerization of anthracene. What merits special attention is that such photo-crosslinked self-assemblies are able to disaggregate reversibly into primary nanoparticles when changing the solution conditions, which is benefited from the designed regular structure of CD-AN and the rigid ranging of anthracene during assembly, thus confirming the process of MMA.

  4. Self-Assembly of Amphiphilic Anthracene-Functionalized β-Cyclodextrin (CD-AN) through Multi-Micelle Aggregation.

    PubMed

    Zhang, Yuannan; Xu, Hongjie; Ma, Xiaodong; Shi, Zixing; Yin, Jie; Jiang, Xuesong

    2016-06-01

    Multi-micelle aggregation (MMA) mechanism is widely acknowledged to explicate large spherical micelles self-assembly, but the process of MMA during self-assembly is hard to observe. Herein, a novel kind of strong, regular microspheres fabricated from self-assembly of amphiphilic anthracene-functionalized β-cyclodextrin (CD-AN) via Cu(I)-catalyzed azide-alkyne click reactions is reported. The obtained CD-AN amphiphiles can self-assemble in water from primary core-shell micelles to secondary aggregates with the diameter changing from several tens nm to around 600-700 nm via MMA process according to the images of scanning electron microscopy, transmission electron microscopy, and atomic force microscopy as well as the dynamic light scattering measurements, followed by further crosslinking through photo-dimerization of anthracene. What merits special attention is that such photo-crosslinked self-assemblies are able to disaggregate reversibly into primary nanoparticles when changing the solution conditions, which is benefited from the designed regular structure of CD-AN and the rigid ranging of anthracene during assembly, thus confirming the process of MMA. PMID:27145434

  5. A New-Anthracene Derivative Containing t-Butyl Group for Solution Process Organic Light-Emitting Diodes.

    PubMed

    Lee, Jaehyun; Kim, Seungho; Kim, Jee-Hwan; Park, Jongwook

    2015-10-01

    4-(10-(3',5'-diphenylbiphenyl-4-yl)anthracen-9-yl)-N,N-diphenylaniline [TATa] and a new anthracene derivative of 4-(2 or 3-tert-butyl-10-(3',5'-diphenylbiphenyl-4-yl)anthracen-9-yl)-N,N-diphenylaniline [T-TATa] isomer by introduced t-butyl group were synthesized. OLED devices of TATa and T-TATa were fabricated by solution process. Its physical properties such as optical, electrochemical, and electroluminescent properties were also investigated. Two compounds were used as emitting layer (EML) in OLED device: ITO/PEDOT (40 nm)/synthesized materials (60 nm)/TPBi (20 nm)/LiF (1 nm)/Al (200 nm). The luminance efficiency of the synthesized compounds at 10 mA/cm2 were measured 0.85 cd/A for TATa and 1.49 cd/A for T-TATa, respectively. Moreover, the power efficiency of T-TATa is 1.08 lm/W. Its value is almost two times higher than 0.56 lm/W of TATa. As a result, more improved efficiency was shown with the device in a compound including t-butyl group to TATa core part, when the deivces were prepared by solution process. PMID:26726504

  6. Crystal structure of [(1,2,3,4,11,12-η)-anthracene]tris-(tri-methyl-stann-yl)cobalt(III).

    PubMed

    Brennessel, William W; Ellis, John E

    2014-11-01

    The asymmetric unit of the title structure, [Co(η(6)-C14H10){Sn(CH3)3}3], contains two independent mol-ecules. Each anthracene ligand is η(6)-coordinating to a Co(III) cation and is nearly planar [fold angles of 5.4 (3) and 9.7 (3)°], as would be expected for its behaving almost entirely as a donor to a high-oxidation-state metal center. The slight fold in each anthracene ligand gives rise to slightly longer Co-C bond lengths to the ring junction carbon atoms than to the other four. Each Co(III) cation is further coordinated by three Sn(CH3)3 ligands, giving each mol-ecule a three-legged piano-stool geometry. In each of the two independent mol-ecules, the trio of SnMe3 ligands are modeled as disordered over two positions, rotated by approximately 30%, such that the C atoms nearly overlap. In one mol-ecule, the disorder ratio refined to 0.9365 (8):0.0635 (8), while that for the other refined to 0.9686 (8):0.0314 (8). The mol-ecules are well separated, and thus no significant inter-molecular inter-actions are observed. The compound is of inter-est as the first structure report of an η(6)-anthracene cobalt(III) complex. PMID:25484731

  7. Changes of benthic bacteria and meiofauna assemblages during bio-treatments of anthracene-contaminated sediments from Bizerta lagoon (Tunisia).

    PubMed

    Ben Said, Olfa; Louati, Hela; Soltani, Amel; Preud'homme, Hugues; Cravo-Laureau, Cristiana; Got, Patrice; Pringault, Olivier; Aissa, Patricia; Duran, Robert

    2015-10-01

    Sediments from Bizerta lagoon were used in an experimental microcosm setup involving three scenarios for the bioremediation of anthracene-polluted sediments, namely bioaugmentation, biostimulation, and a combination of both bioaugmentation and biostimulation. In order to investigate the effect of the biotreatments on the benthic biosphere, 16S rRNA gene-based T-RFLP bacterial community structure and the abundance and diversity of the meiofauna were determined throughout the experiment period. Addition of fresh anthracene drastically reduced the benthic bacterial and meiofaunal abundances. The treatment combining biostimulation and bioaugmentation was most efficient in eliminating anthracene, resulting in a less toxic sedimentary environment, which restored meiofaunal abundance and diversity. Furthermore, canonical correspondence analysis showed that the biostimulation treatment promoted a bacterial community favorable to the development of nematodes while the treatment combining biostimulation and bioaugmentation resulted in a bacterial community that advantaged the development of the other meiofauna taxa (copepods, oligochaetes, polychaetes, and other) restoring thus the meiofaunal structure. The results highlight the importance to take into account the bacteria/meiofauna interactions during the implementation of bioremediation treatment.

  8. Cycloaddition reactions of allenylphosphonates and related allenes with dialkyl acetylenedicarboxylates, 1,3-diphenylisobenzofuran, and anthracene.

    PubMed

    Sajna, K V; Kotikalapudi, Ramesh; Chakravarty, Manab; Bhuvan Kumar, N N; Swamy, K C Kumara

    2011-02-01

    Cycloaddition reactions of allenylphosphonates [(RO)(2)P(O)[(R(1))C═C═CR(2)(2)] with dialkyl acetylenedicarboxylates, 1,3-diphenylisobenzofuran, and anthracene have been investigated and compared with those of allenoates [(EtO(2)C)RC═C═CH(2)] and allenylphosphine oxides [Ph(2)P(O)(R(1))C═C═CR(2)(2)] in selected cases. Allenylphosphonates (RO)(2)P(O)(Ar)C═C═CH(2) with an α-aryl group preferentially undergo [4 + 2] cycloaddition with DMAD/DEAD under thermal activation, but in addition to the expected 1:1 (allene: DMAD) product, the reaction also leads to 1:2 as well as 2:1 products that were not reported before. When an extra vinyl group is present at the γ-carbon of allenylphosphonate [e.g., (OCH(2)CMe(2)CH(2)O)P(O)(Ph)C═C═CH(C═CHMe)], [4 + 2] cycloaddition takes place utilizing either the vinylic or the aryl end, but additionally a novel cyclization wherein complete opening of the [β,γ] carbon-carbon double bond of the allene is realized. In contrast to these, the reaction of allenylphosphonate (OCH(2)CMe(2)CH(2)O)P(O)(H)C═C═CMe(2) possessing a terminal ═CMe(2) group with DMAD occurs by both [2 + 2] cycloaddition and ene reaction. While the reaction of ═CH(2) terminal allenylphosphonates as well as allenylphosphine oxides with 1,3-diphenylisobenzofuran afforded preferentially endo-[4 + 2] cycloaddition products via [α,β] attack, the analogous allenoates [(EtO(2)C)RC═C═CH(2)] underwent exo-[4 + 2] cyclization. Under similar conditions, allenylphosphonates with a terminal ═CR(2) group gave only [β,γ]-cycloaddition products. An unusual ring-opening of a [4 + 2] cycloaddition product followed by ring-closing via [4 + 4] cycloaddition, as revealed by (31)P NMR spectroscopy, is reported. Anthracene reacted in a manner similar to 1,3-diphenylisobenzofuran, albeit with lower reactivity. Key products, including a set of exo- and endo- [4 + 2] cycloaddition products, have been characterized by single crystal X-ray crystallography.

  9. Investigating the Anisotropic Scintillation Response in Anthracene through Neutron, Gamma-Ray, and Muon Measurements

    NASA Astrophysics Data System (ADS)

    Schuster, Patricia; Brubaker, Erik

    2016-06-01

    This paper reports a series of measurements that characterize the directional dependence of the scintillation response of crystalline anthracene to incident DT neutrons, DD neutrons, Cs-137 gamma rays, and, for the first time, cosmic ray muons. The neutron measurements give the amplitude and pulse shape dependence on the proton recoil direction over one hemisphere of the crystal, confirming and extending previous results in the literature. In similar measurements using incident gamma rays, no directional effect is evident, and any anisotropy with respect to the electron recoil direction is constrained to have a magnitude of less than a tenth of that present in the proton recoil events. Cosmic muons are measured at two directions, and no anisotropy is observed. This set of observations indicates that high dE/dx is necessary for an anisotropy to be present for a given type of scintillation event, which in turn could be used to discriminate among different hypotheses for the underlying causes of the anisotropy, which are not well understood.

  10. Diindeno-fusion of an anthracene as a design strategy for stable organic biradicals

    NASA Astrophysics Data System (ADS)

    Rudebusch, Gabriel E.; Zafra, José L.; Jorner, Kjell; Fukuda, Kotaro; Marshall, Jonathan L.; Arrechea-Marcos, Iratxe; Espejo, Guzmán L.; Ponce Ortiz, Rocío; Gómez-García, Carlos J.; Zakharov, Lev N.; Nakano, Masayoshi; Ottosson, Henrik; Casado, Juan; Haley, Michael M.

    2016-08-01

    The consequence of unpaired electrons in organic molecules has fascinated and confounded chemists for over a century. The study of open-shell molecules has been rekindled in recent years as new synthetic methods, improved spectroscopic techniques and powerful computational tools have been brought to bear on this field. Nonetheless, it is the intrinsic instability of the biradical species that limits the practicality of this research. Here we report the synthesis and characterization of a molecule based on the diindeno[b,i]anthracene framework that exhibits pronounced open-shell character yet possesses remarkable stability. The synthetic route is rapid, efficient and possible on the gram scale. The molecular structure was confirmed through single-crystal X-ray diffraction. From variable-temperature Raman spectroscopy and magnetic susceptibility measurements a thermally accessible triplet excited state was found. Organic field-effect transistor device data show an ambipolar performance with balanced electron and hole mobilities. Our results demonstrate the rational design and synthesis of an air- and temperature-stable biradical compound.

  11. Toxicity of 14 photooxidized anthracene derivatives to Lemna gibba L.G-3

    SciTech Connect

    Mallakin, A.; MacConkey, B.J.; McKibbenyen, B.; Sniekusyen, V.; Dixon, D.G.; Greenberg, B.M.

    1995-12-31

    Phototoxicity of PAHs is known to occur via photosensitization reactions and potentially by photomodification of chemicals to more toxic species. The hazards enhancement of polycyclic aromatic hydrocarbon (PAHs) toxicity to plants by artificial light source and natural solar radiation has been recently demonstrated. Growth and chlorosis were used as end points to assess the photoinduced toxicity to 14 oxygenated anthracene derivatives to Lemna gibba. Reversed-phase liquid chromatography (HPLC) equipped with diode array detector was used as analytical technique for measurement of polycyclic aromatic hydrocarbons photomodification products and to study the modification kinetics. The toxicity bioassays were performed both under visible light and simulated solar radiation (SSR), which mimicked the relative load of UV + visible light in solar radiation. Comparative studies with visible and SSR showed that the phototoxicity of these chemicals was activated, with UV radiation being the most influenced spectral region in enhancing the harmful effects of the chemicals. Photomodified PAHs exhibited toxicity in visible light and increased toxicity in simulate solar radiation. The rates of photomodification of chemicals were quite different but rapid enough to contribute to toxicity. There was increase in inhibition of growth of plants, relative to control, with increasing in rate of photomodification of the oxygenated PAHs.

  12. Taurine Attenuates Dimethylbenz[a]anthracene-induced Breast Tumorigenesis in Rats: A Plasma Metabolomic Study.

    PubMed

    He, Y U; Li, Qingdi Quentin; Guo, Song Chao

    2016-02-01

    Breast cancer is the most common malignancy and the leading cause of cancer-related mortality in women worldwide. Taurine, the most abundant free amino acid, plays a role in several biological processes in humans and has been shown to have activity against breast cancer and other tumors. To investigate the role and mechanism of taurine action in breast cancer, we used dimethylbenz[a]anthracene (DMBA)-induced breast carcinogenesis in rats as a model of breast cancer. The administration of taurine significantly reduced the DMBA-induced breast cancer rate from 80% to 40% in rats (p<0.05). Metabolomic studies using time-of-flight gas chromatography-mass spectrometry identified 23 differential metabolites in the plasma of taurine-administered rats. Bioinformatic analysis further revealed that these metabolites are involved in multiple metabolic pathways, including energy, glucose, amino acid, and nucleic acid metabolism, suggesting that the antitumor activity of taurine in rats is mediated through altered metabolism of breast cancer cells. We propose that these differential metabolites may be potential biomarkers for monitoring cancer therapy and prognosis in the clinic. This study provides a scientific basis for further investigations of the antitumor mechanism of taurine and the development of novel therapeutic strategies to treat breast cancer. PMID:26851007

  13. Localization of specific lesions in dimethylbenz(a)anthracene-preexposed tracheal explants

    SciTech Connect

    Marchok, A.C.; Nettesheim, P.; Johnston, W.W.

    1982-12-01

    An experimental model is described for separating out and identifying, by a nondestructive method, lesions induced in rat tracheal implants exposed to 200 ..mu..g dimethylbenz(a)anthracene (DMBA)-beeswax pellets. The approach was to cut exposed and nonexposed tracheas into 2 x 3-mm explants and place them in organ culture for 24 hours. The medium was collected, and the exfoliated cells in the medium were stained by the Papanicolaou method for cytologic diagnosis. The exfoliated cells were graded according to the degree of atypia by conventional cytologic criteria. To validate the cytologic diagnoses, 60 organ cultures were fixed, sectioned, and stained; and the histopathologic diagnoses were compared. In most cases, the cytologic findings were predictive of the histopathologic results. To test for alterations in growth characteristics of cell populations derived from specific lesions, epithelial cell cultures were established from 35 organ cultures. All primary cultures from explants showing moderate or more severe atypia, and 40% from those showing regular metaplasia or mildly atypical lesions, survived and grew in culture. Cultures from unexposed tracheas did not survive.

  14. The anharmonic quartic force field infrared spectra of three polycyclic aromatic hydrocarbons: Naphthalene, anthracene, and tetracene

    SciTech Connect

    Mackie, Cameron J. Candian, Alessandra; Tielens, Alexander G. G. M.; Huang, Xinchuan; Maltseva, Elena; Buma, Wybren Jan; Petrignani, Annemieke; Oomens, Jos; Lee, Timothy J.

    2015-12-14

    Current efforts to characterize and study interstellar polycyclic aromatic hydrocarbons (PAHs) rely heavily on theoretically predicted infrared (IR) spectra. Generally, such studies use the scaled harmonic frequencies for band positions and double harmonic approximation for intensities of species, and then compare these calculated spectra with experimental spectra obtained under matrix isolation conditions. High-resolution gas-phase experimental spectroscopic studies have recently revealed that the double harmonic approximation is not sufficient for reliable spectra prediction. In this paper, we present the anharmonic theoretical spectra of three PAHs: naphthalene, anthracene, and tetracene, computed with a locally modified version of the SPECTRO program using Cartesian derivatives transformed from Gaussian 09 normal coordinate force constants. Proper treatments of Fermi resonances lead to an impressive improvement on the agreement between the observed and theoretical spectra, especially in the C–H stretching region. All major IR absorption features in the full-scale matrix-isolated spectra, the high-temperature gas-phase spectra, and the most recent high-resolution gas-phase spectra obtained under supersonically cooled molecular beam conditions in the CH-stretching region are assigned.

  15. Investigating the anisotropic scintillation response in anthracene through neutron, gamma-ray, and muon measurements

    DOE PAGESBeta

    Schuster, Patricia; Brubaker, Erik

    2016-05-05

    Our paper reports a series of measurements that characterize the directional dependence of the scintillation response of crystalline anthracene to incident DT neutrons, DD neutrons, 137Cs gamma rays, and, for the first time, cosmic ray muons. Moreover, the neutron measurements give the amplitude and pulse shape dependence on the proton recoil direction over one hemisphere of the crystal, confirming and extending previous results in the literature. In similar measurements using incident gamma rays, no directional effect is evident, and any anisotropy with respect to the electron recoil direction is constrained to have a magnitude of less than a tenth ofmore » that present in the proton recoil events. Cosmic muons are measured at two directions, and no anisotropy is observed. Our set of observations indicates that high dE/dx is necessary for an anisotropy to be present for a given type of scintillation event, which in turn could be used to discriminate among different hypotheses for the underlying causes of the anisotropy, which are not well understood.« less

  16. High temperature polyimide containing anthracene moiety and its structure, interface, and nonvolatile memory behavior.

    PubMed

    Park, Samdae; Kim, Kyungtae; Kim, Dong Min; Kwon, Wonsang; Choi, Junman; Ree, Moonhor

    2011-03-01

    A high temperature polyimide bearing anthracene moieties, poly(3,3'-di(9-anthracenemethoxy)-4,4'-biphenylene hexafluoroisopropylidenediphthalimide) (6F-HAB-AM PI) was synthesized. The polymer exhibits excellent thermal stability up to around 410 °C. This polymer is amorphous but orients preferentially in the plane of nanoscale thin films. In device fabrications of its nanoscale thin films with metal top and bottom electrodes, no diffusion of the metal atoms or ions between the polymer and electrodes was found; however, the aluminum bottom electrode had somewhat undergone oxide layer (about 1.2 nm thick) formation at the surface during the post polymer layer formation process, which was confirmed to have no significant influence on the device performance. The polymer thin film exhibited excellent unipolar and bipolar switching behaviors over a very small voltage range, less than ±2 V. Further, the PI films show repeatable writing, reading, and erasing ability with long reliability and high ON/OFF current ratio (up to 10(7)) in air ambient conditions as well as even at temperatures up to 200 °C. PMID:21338065

  17. Helium induced fine structure in the electronic spectra of anthracene derivatives doped into superfluid helium nanodroplets

    SciTech Connect

    Pentlehner, D.; Slenczka, A.

    2015-01-07

    Electronic spectra of organic molecules doped into superfluid helium nanodroplets show characteristic features induced by the helium environment. Besides a solvent induced shift of the electronic transition frequency, in many cases, a spectral fine structure can be resolved for electronic and vibronic transitions which goes beyond the expected feature of a zero phonon line accompanied by a phonon wing as known from matrix isolation spectroscopy. The spectral shape of the zero phonon line and the helium induced phonon wing depends strongly on the dopant species. Phonon wings, for example, are reported ranging from single or multiple sharp transitions to broad (Δν > 100 cm{sup −1}) diffuse signals. Despite the large number of example spectra in the literature, a quantitative understanding of the helium induced fine structure of the zero phonon line and the phonon wing is missing. Our approach is a systematic investigation of related molecular compounds, which may help to shed light on this key feature of microsolvation in superfluid helium droplets. This paper is part of a comparative study of the helium induced fine structure observed in electronic spectra of anthracene derivatives with particular emphasis on a spectrally sharp multiplet splitting at the electronic origin. In addition to previously discussed species, 9-cyanoanthracene and 9-chloroanthracene will be presented in this study for the first time.

  18. Direct Observation of the Photodegradation of Anthracene and Pyrene Adsorbed onto Mangrove Leaves

    PubMed Central

    Wang, Ping; Wu, Tun-Hua; Zhang, Yong

    2014-01-01

    An established synchronous fluorimetry method was used for in situ investigation of the photodegradation of pyrene (PYR) and anthracene (ANT) adsorbed onto fresh leaves of the seedlings of two mangrove species, Aegiceras corniculatum (L.) Blanco (Ac) and Kandelia obovata (Ko) in multicomponent mixtures (mixture of the ANT and PYR). Experimental results indicated that photodegradation was the main transformation pathway for both ANT and PYR in multicomponent mixtures. The amount of the PAHs volatilizing from the leaf surfaces and entering the inner leaf tissues was negligible. Over a certain period of irradiation time, the photodegradation of both PYR and ANT adsorbed onto the leaves of Ac and Ko followed first-order kinetics, with faster rates being observed on Ac leaves. In addition, the photodegradation rate of PYR on the leaves of the mangrove species in multicomponent mixtures was much slower than that of adsorbed ANT. Compared with the PAHs adsorbed as single component, the photodegradation rate of ANT adsorbed in multicomponent mixtures was slower, while that of PYR was faster. Moreover, the photodegradation of PYR and ANT dissolved in water in multicomponent mixtures was investigated for comparison. The photodegradation rate on leaves was much slower than in water. Therefore, the physical-chemical properties of the substrate may strongly influence the photodegradation rate of adsorbed PAHs. PMID:25144741

  19. Crystal induced phosphorescence from Benz(a)anthracene microcrystals at room temperature

    NASA Astrophysics Data System (ADS)

    Maity, Samir; Mazumdar, Prativa; Shyamal, Milan; Sahoo, Gobinda Prasad; Misra, Ajay

    2016-03-01

    Pure organic compounds that are also phosphorescent at room temperature are very rare in literature. Here, we report efficient phosphorescence emission from aggregated hydrosol of Benz(a)anthracene (BaA) at room temperature. Aggregated hydrosol of BaA has been synthesized by re-precipitation method and SDS is used as morphology directing agent. Morphology of the particles is characterized using optical and scanning electronic microcopy (SEM). Photophysical properties of the aggregated hydrosol are carried out using UV-vis, steady state and time resolved fluorescence study. The large stoke shifted structured emission from aggregated hydrosol of BaA has been explained due to phosphorescence emission of BaA at room temperature. In the crystalline state, the restricted intermolecular motions (RIM) such as rotations and vibrations are activated by crystal lattice. This rigidification effect makes the chromophore phosphorescent at room temperature. The possible stacking arrangement of the neighboring BaA within the aggregates has been substantiated by computing second order Fukui parameter as local reactivity descriptors. Computational study also reveals that the neighboring BaA molecules are present in parallel slipped conformation in its aggregated crystalline form.

  20. Monte Carlo Study of the Fish-like Patterns of Anthracenes on Cu(111)

    NASA Astrophysics Data System (ADS)

    Kim, Kwangmoo; Einstein, T. L.; Sun, Dezheng; Kim, Dae-Ho; Bartels, Ludwig

    2011-03-01

    Using Monte Carlo calculations of the two-dimensional triangular lattice with a 2-component 3-state Potts model, we demonstrate a mechanism for the spontaneous formation of fish-like patterns of anthracene (AC) molecules on Cu(111) by sputtering and annealing, then cooling to ~ 80 K. The two components are an AC on a hollow site and another on a bridge site of Cu(111). The liquid crystal model with two separate parts, positional and orientational, only explains a part of the fish-like pattern, not the whole regular pattern. Our model fixes the positional order of AC's into the triangular lattice and the orientational order into three angles as observed in the experiments. The variation of the coverages of AC's is reflected in the change of the ratio of two components in our model. We also try to understand the compression of AC's with the introduction of Gaussian dispersion of AC's about their triangular lattice sites. Supported primarily by NSF Grants CHE 07-50334 with a secondary support from NSF-MRSEC at the University of Maryland, DMR05-20471. Work at UCR supported primarily by NSF CHE 07-49949.

  1. Diindeno-fusion of an anthracene as a design strategy for stable organic biradicals.

    PubMed

    Rudebusch, Gabriel E; Zafra, José L; Jorner, Kjell; Fukuda, Kotaro; Marshall, Jonathan L; Arrechea-Marcos, Iratxe; Espejo, Guzmán L; Ponce Ortiz, Rocío; Gómez-García, Carlos J; Zakharov, Lev N; Nakano, Masayoshi; Ottosson, Henrik; Casado, Juan; Haley, Michael M

    2016-08-01

    The consequence of unpaired electrons in organic molecules has fascinated and confounded chemists for over a century. The study of open-shell molecules has been rekindled in recent years as new synthetic methods, improved spectroscopic techniques and powerful computational tools have been brought to bear on this field. Nonetheless, it is the intrinsic instability of the biradical species that limits the practicality of this research. Here we report the synthesis and characterization of a molecule based on the diindeno[b,i]anthracene framework that exhibits pronounced open-shell character yet possesses remarkable stability. The synthetic route is rapid, efficient and possible on the gram scale. The molecular structure was confirmed through single-crystal X-ray diffraction. From variable-temperature Raman spectroscopy and magnetic susceptibility measurements a thermally accessible triplet excited state was found. Organic field-effect transistor device data show an ambipolar performance with balanced electron and hole mobilities. Our results demonstrate the rational design and synthesis of an air- and temperature-stable biradical compound.

  2. The anharmonic quartic force field infrared spectra of three polycyclic aromatic hydrocarbons: Naphthalene, anthracene, and tetracene

    NASA Astrophysics Data System (ADS)

    Mackie, Cameron J.; Candian, Alessandra; Huang, Xinchuan; Maltseva, Elena; Petrignani, Annemieke; Oomens, Jos; Buma, Wybren Jan; Lee, Timothy J.; Tielens, Alexander G. G. M.

    2015-12-01

    Current efforts to characterize and study interstellar polycyclic aromatic hydrocarbons (PAHs) rely heavily on theoretically predicted infrared (IR) spectra. Generally, such studies use the scaled harmonic frequencies for band positions and double harmonic approximation for intensities of species, and then compare these calculated spectra with experimental spectra obtained under matrix isolation conditions. High-resolution gas-phase experimental spectroscopic studies have recently revealed that the double harmonic approximation is not sufficient for reliable spectra prediction. In this paper, we present the anharmonic theoretical spectra of three PAHs: naphthalene, anthracene, and tetracene, computed with a locally modified version of the SPECTRO program using Cartesian derivatives transformed from Gaussian 09 normal coordinate force constants. Proper treatments of Fermi resonances lead to an impressive improvement on the agreement between the observed and theoretical spectra, especially in the C-H stretching region. All major IR absorption features in the full-scale matrix-isolated spectra, the high-temperature gas-phase spectra, and the most recent high-resolution gas-phase spectra obtained under supersonically cooled molecular beam conditions in the CH-stretching region are assigned.

  3. Diindeno-fusion of an anthracene as a design strategy for stable organic biradicals.

    PubMed

    Rudebusch, Gabriel E; Zafra, José L; Jorner, Kjell; Fukuda, Kotaro; Marshall, Jonathan L; Arrechea-Marcos, Iratxe; Espejo, Guzmán L; Ponce Ortiz, Rocío; Gómez-García, Carlos J; Zakharov, Lev N; Nakano, Masayoshi; Ottosson, Henrik; Casado, Juan; Haley, Michael M

    2016-08-01

    The consequence of unpaired electrons in organic molecules has fascinated and confounded chemists for over a century. The study of open-shell molecules has been rekindled in recent years as new synthetic methods, improved spectroscopic techniques and powerful computational tools have been brought to bear on this field. Nonetheless, it is the intrinsic instability of the biradical species that limits the practicality of this research. Here we report the synthesis and characterization of a molecule based on the diindeno[b,i]anthracene framework that exhibits pronounced open-shell character yet possesses remarkable stability. The synthetic route is rapid, efficient and possible on the gram scale. The molecular structure was confirmed through single-crystal X-ray diffraction. From variable-temperature Raman spectroscopy and magnetic susceptibility measurements a thermally accessible triplet excited state was found. Organic field-effect transistor device data show an ambipolar performance with balanced electron and hole mobilities. Our results demonstrate the rational design and synthesis of an air- and temperature-stable biradical compound. PMID:27442280

  4. The anharmonic quartic force field infrared spectra of three polycyclic aromatic hydrocarbons: Naphthalene, anthracene, and tetracene.

    PubMed

    Mackie, Cameron J; Candian, Alessandra; Huang, Xinchuan; Maltseva, Elena; Petrignani, Annemieke; Oomens, Jos; Buma, Wybren Jan; Lee, Timothy J; Tielens, Alexander G G M

    2015-12-14

    Current efforts to characterize and study interstellar polycyclic aromatic hydrocarbons (PAHs) rely heavily on theoretically predicted infrared (IR) spectra. Generally, such studies use the scaled harmonic frequencies for band positions and double harmonic approximation for intensities of species, and then compare these calculated spectra with experimental spectra obtained under matrix isolation conditions. High-resolution gas-phase experimental spectroscopic studies have recently revealed that the double harmonic approximation is not sufficient for reliable spectra prediction. In this paper, we present the anharmonic theoretical spectra of three PAHs: naphthalene, anthracene, and tetracene, computed with a locally modified version of the SPECTRO program using Cartesian derivatives transformed from Gaussian 09 normal coordinate force constants. Proper treatments of Fermi resonances lead to an impressive improvement on the agreement between the observed and theoretical spectra, especially in the C-H stretching region. All major IR absorption features in the full-scale matrix-isolated spectra, the high-temperature gas-phase spectra, and the most recent high-resolution gas-phase spectra obtained under supersonically cooled molecular beam conditions in the CH-stretching region are assigned. PMID:26671382

  5. Bioavailability and dissipation of anthracene from soil with different alkalinity and salinity.

    PubMed

    Castro-Silva, Carolina; Ruiz-Valdiviezo, Víctor Manuel; Rivas-Rivera, Sandra Gabriela; Sosa-Trinidad, Alma Rosa; Luna-Guido, Marco; Delgado-Balbuena, Laura; Marsch, Rodolfo; Dendooven, Luc

    2015-01-01

    Bioavailability of contaminants, such as anthracene (Anthra), a polycyclic aromatic hydrocarbon (PAHs), and their removal from soil has been related to their extractability with non-exhaustive techniques, such as hydroxypropyl-beta-cyclodextrin (HPCD) or n-butanol. Anthra was extracted with HPCD, n-butanol and by exhaustive ultrasonic extraction method from sterilized and unsterilized alkaline soil of the former lake Texcoco, having pH ranging from pH 8.2 to 10.1 and electrolytic conductivity varying from 1.2 dS m(-1) to 95.2 dS m(-1), respectively. About 24.4 and 37.6% of Anthra was removed biologically from soil as estimated by exhaustive technique after 56 days. The percentage of Anthra that was removed from soil by exhaustive technique was not related to the amount thatwas extractable with HPCD or n-butanol. It was found that the Anthra extractable with n-butanol or HPCD did not correlate well with the removal of the contaminant from soil. In this study, the removal of Anthra from soil could not be predicted by the amount of Anthra that was extracted with n-butanol or HPCD .

  6. Catalase-like activity of bovine met-hemoglobin: interaction with the pseudo-catalytic peroxidation of anthracene traces in aqueous medium.

    PubMed

    Paco, Laveille; Galarneau, Anne; Drone, Jullien; Fajula, François; Bailly, Carole; Pulvin, Sylviane; Thomas, Daniel

    2009-10-01

    Hemoglobin is a member of the hemoprotein superfamily whose main role is to transport O(2) in vertebrate organisms. It has two known promiscuous enzymatic activities, peroxidase and oxygenase. Here we show for the first time that bovine hemoglobin also presents a catalase-like activity characterized by a V(max )of 344 microM/min, a K(M )of 24 mM and a k(cat) equal to 115/min. For high anthracene and hemoglobin concentrations and low hydrogen peroxide concentrations, this activity inhibits the expected oxidation of anthracene, which occurs through a peroxidase-like mechanism. Anthracene belongs to the polycyclic aromatic hydrocarbon (PAH) family whose members are carcinogenic and persistent pollutants found in industrial waste waters. Our results show that anthracene oxidation by hemoglobin and hydrogen peroxide follows a typical bi-bi ping-pong mechanism with a V(max) equal to 0.250 microM/min, K(M(H2O2) )of 80 microM, K(M(ANT)) of 1.1 microM and k(cat) of 0.17/min. The oxidation of anthracene is shown to be pseudo-catalytic because an excess of hemoglobin and hydrogen peroxide is required to make PAH completely disappear. Thus, bovine hemoglobin presents, in different degrees, all the catalytic activities of the hemoprotein group, which makes it a very interesting protein for biotechnological processes and one with which structure-activity relationships can be studied.

  7. Synthesis, characterization and properties of yellow-light-emitting polyethers containing bis(styryl)anthracene units

    NASA Astrophysics Data System (ADS)

    Gioti, M.; Pitsalidis, C.; Andreopoulou, A. K.; Mparmpoutsis, E.; Tzounis, L.; Kallitsis, J. K.; Logothetidis, S.

    2015-02-01

    Aromatic aliphatic polyethers containing bis(styryl)anthracene units in the main chain separated by flexible spacer of 11 (AND52) or 12 (AND53) methylene units, were synthesized and characterized aiming to be applied as emitting materials in polymer light emitting diode (PLED) devices. The polymers are soluble in common organic solvents and have average molecular weight of about 15kDa. Differentiations owing to an odd-even number of methylene units (χ=11 vs χ=12) are observed in their optical properties in solid state. Thin films as well as PLED devices were fabricated via conventional spin-coating process. Initially, various parameters have been investigated concerning the solubility of the polymers, the effect of film thickness on the electrical properties, and their thermal stability. The optical properties of the two polymers were investigated by NIR-Vis-far UV spectroscopic ellipsometry (SE). The accurate determination of the thickness and the optical constants (refractive index and dielectric function as a function of wavelength) were derived. These provide substantial insights into the final design of the optimum final multi-layer structure of the PLEDs, if we take into account that the external quantum efficiency (EQE) of electroluminescence (EL) strongly depends on the optical interference of the beams of emitted light that have been multiply reflected from the layer interfaces. The morphological characterization of the AND52 and AND53 polymeric thin films was carried out using atomic force microscopy (AFM), while current density-voltage (J-V) characteristics of the devices were studied by electrical measurements. The single PLED devices were switched on at relatively low operation voltages, showing the potential as backplanes for active matrix PLED applications. In this perspective, it can be assumed that further studies of the presented materials will enable the development of flexible PLEDs with the possibility to scale up their dimensions for bigger

  8. A search for interstellar anthracene towards the Perseus anomalous microwave emission region

    NASA Astrophysics Data System (ADS)

    Iglesias-Groth, S.; Manchado, A.; Rebolo, R.; González Hernández, J. I.; García-Hernández, D. A.; Lambert, D. L.

    2010-10-01

    We report the discovery of a new broad interstellar (or circumstellar) band at 7088.8 +/- 2.0 Å coincident to within the measurement uncertainties with the strongest band of the anthracene cation (C14H10+) as measured in gas-phase laboratory spectroscopy at low temperatures. The band is detected in the line of sight of star Cernis 52, a likely member of the very young star cluster IC 348, and is probably associated with cold absorbing material in an intervening molecular cloud of the Perseus star-forming region where various experiments have recently detected anomalous microwave emission. From the measured intensity and available oscillator strength we find a column density of implying that ~0.008 per cent of the carbon in the cloud could be in the form of C14H10+. A similar abundance has been recently claimed for the naphthalene cation in this cloud. This is the first location outside the Solar system where specific polycyclic aromatic hydrocarbons (PAHs) are identified. We report observations of interstellar lines of CH and CH+ that support a rather high column density for these species and for molecular hydrogen. The strength ratio of the two prominent diffuse interstellar bands at 5780 and 5797 Å suggests the presence of a `zeta'-type cloud in the line of sight (consistent with steep far-ultraviolet extinction and high molecular content). The presence of PAH cations and other related hydrogenated carbon molecules which are likely to occur in this type of clouds reinforces the suggestion that electric dipole radiation from fast-spinning PAHs is responsible of the anomalous microwave emission detected towards Perseus.

  9. Dramatic improvements in viral inactivation with brominated psoralens, naphthalenes and anthracenes.

    PubMed

    Rai, S; Kasturi, C; Grayzar, J; Platz, M S; Goodrich, R P; Yerram, N R; Wong, V; Tay-Goodrich, B H

    1993-07-01

    Amino or polyamino derivatives of naphthalene (N-H), anthracene (A-H) and 8-alkoxypsoralen (PSR-H) were prepared along with their monobrominated analogs (N-Br, A-Br and PSR-Br). The ammonium salts of these compounds are all water soluble and bind strongly to calf thymus DNA and to lambda phage, a double-helical DNA, protein-coated virus. Binding of the sensitizer to DNA occurs, presumably by a mixture of hydrophobic, intercalative and electrostatic interactions. Relative binding constants to calf thymus DNA and to lambda phage were measured by the ethidium bromide fluorescence quenching assay. In general the brominated analogs bind more tightly to calf thymus DNA and to the virus than to the nonhalogenated analogs. It is demonstrated that the brominated aromatics are much more effective at inactivating lambda phage upon photoactivation (lambda approximately 310 or 350 nm) than are their nonbrominated analogs. At identical sensitizer concentrations (by weight) and light flux N-Br, A-Br, and PSR-Br produce 5-6 more logs of viral inactivation than their nonbrominated counterparts (N-H, A-H and PSR-H, respectively). The bromine effect may originate from light-induced electron transfer and subsequent cleavage of the C-Br bond of the sensitizer radical anion bonds to form aryl radicals. Singlet oxygen cannot be responsible for the viral inactivation because the brominated sensitizers are equally effective in the presence and absence of oxygen. Dithiothreitol does not protect lambda phage from light-induced inactivation by the brominated sensitizer thereby demonstrating that the photogenerated reactive intermediates responsible for the effect are complexed to the virus and are not generated free in solution. PMID:8378434

  10. Persistence and fate of anthracene and benzo(a)pyrene in municipal sludge treated soil

    SciTech Connect

    Goodin, J.D.; Webber, M.D.

    1995-03-01

    Greenhouse studies using pots and microcosms were conducted to investigate the persistence and fate of nonlabeled and {sup 14}C-labeled anthracene (ANT) and benzo(a)Pyrene (B(a)P) in sludge treated soil. Results indicated that ANT degraded rapidly (t{sub {1/2}} {approx} 3 wk) from the experimental systems, but that B(a)P was persistent. Cropping did not affect the persistence of either compound. On completion of the experiments {le} 10% of the ANT added to soil was recovered intact, whereas 78% of the B(a)P added to soil was recovered intact. Most ({ge}85%) of the {sup 14}C added to soil as labeled ANT and B(a)P was accounted for. Recoveries of {sup 14}CO{sub 2} indicated significant mineralization of ANT, but not of B(a)P. Trivial amounts ({le}0.2%) of {sup 14}C were recovered as volatile organics and in plant materials, but large amounts were recovered from soil. A considerable proportion of the ANT derived {sup 14}C in soil was not extracted with acetone/hexane, which indicated that it had been converted to bound residue. a much smaller proportion of B(a)P than of ANT derived {sup 14}C in soil was converted to bound residue. No evidence was obtained for uptake of intact ANT or B(a)P by ryegrass (lolium multiflorum Lam.), soybean [Glycinemax (L.) Merr.], and cabbage (Brassica oleracea var. capitata L.). 25 refs., 3 figs., 6 tabs.

  11. Synthesis, characterization and properties of yellow-light-emitting polyethers containing bis(styryl)anthracene units

    SciTech Connect

    Gioti, M. Pitsalidis, C. Tzounis, L.; Logothetidis, S.; Andreopoulou, A. K.; Kallitsis, J. K.; Mparmpoutsis, E.

    2015-02-17

    Aromatic aliphatic polyethers containing bis(styryl)anthracene units in the main chain separated by flexible spacer of 11 (AND52) or 12 (AND53) methylene units, were synthesized and characterized aiming to be applied as emitting materials in polymer light emitting diode (PLED) devices. The polymers are soluble in common organic solvents and have average molecular weight of about 15kDa. Differentiations owing to an odd-even number of methylene units (χ=11 vs χ=12) are observed in their optical properties in solid state. Thin films as well as PLED devices were fabricated via conventional spin-coating process. Initially, various parameters have been investigated concerning the solubility of the polymers, the effect of film thickness on the electrical properties, and their thermal stability. The optical properties of the two polymers were investigated by NIR-Vis-far UV spectroscopic ellipsometry (SE). The accurate determination of the thickness and the optical constants (refractive index and dielectric function as a function of wavelength) were derived. These provide substantial insights into the final design of the optimum final multi-layer structure of the PLEDs, if we take into account that the external quantum efficiency (EQE) of electroluminescence (EL) strongly depends on the optical interference of the beams of emitted light that have been multiply reflected from the layer interfaces. The morphological characterization of the AND52 and AND53 polymeric thin films was carried out using atomic force microscopy (AFM), while current density-voltage (J-V) characteristics of the devices were studied by electrical measurements. The single PLED devices were switched on at relatively low operation voltages, showing the potential as backplanes for active matrix PLED applications. In this perspective, it can be assumed that further studies of the presented materials will enable the development of flexible PLEDs with the possibility to scale up their dimensions for bigger

  12. A multilayer MCTDH study on the full dimensional vibronic dynamics of naphthalene and anthracene cations

    NASA Astrophysics Data System (ADS)

    Meng, Qingyong; Meyer, Hans-Dieter

    2013-01-01

    Employing the multilayer multiconfiguration time-dependent Hartree (ML-MCTDH) method in conjunction with the multistate multimode vibronic coupling Hamiltonian model, we perform a full dimensional quantum dynamical study on the naphthalene (48D) and anthracene (66D) radical cations in their six lowest-lying doublet electronic states. For easily comparing results of full and reduced dimensionalities, MCTDH simulations based on larger sizes of primitive basis functions and single-particle functions than the previous ones [S. Ghanta, V. S. Reddy, and S. Mahapatra, Phys. Chem. Chem. Phys. 13, 14531 (2011)], 10.1039/c1cp21084j, are also performed. Extensive ML-MCTDH test calculations are performed to find appropriate ML separations of the wave functions (so-called ML-trees), and the convergence of the dynamical calculations are carefully checked. The ML-MCTDH method was developed for efficiently simulating quantum dynamics of large systems, and in fact the full dimensional ML-MCTDH calculations save a considerable amount of CPU-time in comparison with corresponding reduced dimensional MCTDH simulations. On basis of the present full and reduced dimensional simulations, the photoelectron (PE) spectra of these two cations are simulated and compared with corresponding experimental spectra. The agreement between theoretical and experimental PE spectra is good. Both full and reduced dimensional simulations give all main bands in the PE spectra. The vibronic energy-level positions from both ML-MCTDH and MCTDH calculations agree with corresponding experimental results. These quantum dynamical studies also complement the observations on diffuse interstellar bands with the wavelength of ˜7088, ˜6707, ˜6490, ˜6120, and ˜5959 Å measured by astronomers as well as laboratory experimentalists.

  13. A multilayer MCTDH study on the full dimensional vibronic dynamics of naphthalene and anthracene cations.

    PubMed

    Meng, Qingyong; Meyer, Hans-Dieter

    2013-01-01

    Employing the multilayer multiconfiguration time-dependent Hartree (ML-MCTDH) method in conjunction with the multistate multimode vibronic coupling Hamiltonian model, we perform a full dimensional quantum dynamical study on the naphthalene (48D) and anthracene (66D) radical cations in their six lowest-lying doublet electronic states. For easily comparing results of full and reduced dimensionalities, MCTDH simulations based on larger sizes of primitive basis functions and single-particle functions than the previous ones [S. Ghanta, V. S. Reddy, and S. Mahapatra, Phys. Chem. Chem. Phys. 13, 14531 (2011)], are also performed. Extensive ML-MCTDH test calculations are performed to find appropriate ML separations of the wave functions (so-called ML-trees), and the convergence of the dynamical calculations are carefully checked. The ML-MCTDH method was developed for efficiently simulating quantum dynamics of large systems, and in fact the full dimensional ML-MCTDH calculations save a considerable amount of CPU-time in comparison with corresponding reduced dimensional MCTDH simulations. On basis of the present full and reduced dimensional simulations, the photoelectron (PE) spectra of these two cations are simulated and compared with corresponding experimental spectra. The agreement between theoretical and experimental PE spectra is good. Both full and reduced dimensional simulations give all main bands in the PE spectra. The vibronic energy-level positions from both ML-MCTDH and MCTDH calculations agree with corresponding experimental results. These quantum dynamical studies also complement the observations on diffuse interstellar bands with the wavelength of ~7088, ~6707, ~6490, ~6120, and ~5959 Å measured by astronomers as well as laboratory experimentalists. PMID:23298047

  14. Highly efficient blue organic light-emitting diodes using dual emissive layers with host-dopant system

    NASA Astrophysics Data System (ADS)

    Lee, Bo Mi; Yu, Hyeong Hwa; Kim, You Hyun; Kim, Nam Ho; Yoon, Ju An; Mascher, Peter; Kim, Woo Young

    2012-10-01

    In this study, we fabricated highly efficient blue organic light-emitting diodes by designing different emitting layer structures with fluorescent host and dopant materials of 4,4-bis(2,2-diphenylyinyl)-1,10-biphenyl (DPVBi) and 9,10- bis(2-naphthyl) anthracene (ADN) as host materials and 4,4'-bis(9-ethyl-3-carbazovinylene)-1,1'biphenyl (BCzVBi) as a dopant material to demonstrate electrical and optical improvements. Best enhancement in luminance and luminous efficiency were achieved by a quantum well structure and energy transfer between host and dopant materials in device F as of 8668cd/m2 at 8V and 5.16 Cd/A at 103.20 mA/cm2 respectively. Among the blue OLED devices doped by BCzVBi, device B emits the deepest blue emission with Commission Internationale de l'É clairage (CIExy) coordinates of (0.157, 0.117) at 8V.

  15. High-efficient and brightness white organic light-emitting diodes operated at low bias voltage

    NASA Astrophysics Data System (ADS)

    Zhang, Lei; Yu, Junsheng; Yuan, Kai; Jian, Yadong

    2010-10-01

    White organic light-emitting diodes (OLEDs) used for display application and lighting need to possess high efficiency, high brightness, and low driving voltage. In this work, white OLEDs consisted of ambipolar 9,10-bis 2-naphthyl anthracene (ADN) as a host of blue light-emitting layer (EML) doped with tetrabutyleperlene (TBPe) and a thin codoped layer consisted of N, N'-bis(naphthalen-1-yl)-N,N'-bis(phenyl)-benzidine (NPB) as a host of yellow light-emitting layer doped with 4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethyljulolidin-4-yl-vinyl)-4H-pyran (DCJTB) were investigated. With appropriate tuning in the film thickness, position, and dopant concentration of the co-doped layer, a white OLED with a luminance yield of 10.02 cd/A with the CIE coordinates of (0.29, 0.33) has been achieved at a bias voltage of 9 V and a luminance level of over 10,000 cd/m2. By introducing the PIN structure with both HIL and bis(10- hydroxybenzo-quinolinato)-beryllium (BeBq2) ETL, the power efficiency of white OLED was improved.

  16. High-efficiency and long-lifetime fluorescent blue organic-emitting device

    NASA Astrophysics Data System (ADS)

    Ho, Yu-Hsuan; Lin, Tien-Chun; Wu, Chia-Fang; Lee, Jiun-Haw

    2006-08-01

    In this paper, We have demonstrated a blue fluorescent organic light-emitting device (OLED) with a current efficiency of 19.2 cd/A at 100 cd/m2, an estimated half-lifetime of 15611 hours at an initial luminance of 1000 cd/m2, and a voltage of 4.9 V at 20 mA/cm2 with a high electron mobility electron transport layer (ETL) material and high efficiency dopant material. The external quantum efficiency (EQE) in this optimized OLED is 8.32%, which is very close to the theoretical limit. Carrier balance condition is achieved due to the incorporation of the high mobility ETL, bis(10- hydroxyben-zo[h]quinolinato)beryllium (Bebq2), which can not only effectively increase the current efficiency and elongate the operation lifetime, but also reduce the driving voltage and increase the power efficiency. The EML consisted of 4,4'-bis[2-(4-(N,N-diphenylamino)phenyl)vinyl]biphenyl (DPAVBi) as the blue dopant and 9,10-bis(2'- naphthyl) anthracene (ADN) as the matrix. We found that the dopant concentration of DPAVBi did not affect the mobility value of the EML which is consistent with the J-V characteristics. Besides, although it is believed the bulk ADN is a kind of HTL materials, we found the electron mobility of ADN is one order of magnitude higher than its hole mobility in our blue OLEDs.

  17. Determination of Anthracene on Ag-Au Alloy Nanoparticles/Overoxidized-Polypyrrole Composite Modified Glassy Carbon Electrodes

    PubMed Central

    Mailu, Stephen N.; Waryo, Tesfaye T.; Ndangili, Peter M.; Ngece, Fanelwa R.; Baleg, Abd A.; Baker, Priscilla G.; Iwuoha, Emmanuel I.

    2010-01-01

    A novel electrochemical sensor for the detection of anthracene was prepared by modifying a glassy carbon electrode (GCE) with over-oxidized polypyrrole (PPyox) and Ag-Au (1:3) bimetallic nanoparticles (Ag-AuNPs). The composite electrode (PPyox/Ag-AuNPs/GCE) was prepared by potentiodynamic polymerization of pyrrole on GCE followed by its overoxidation in 0.1 M NaOH. Ag-Au bimetallic nanoparticles were chemically prepared by the reduction of AgNO3 and HAuCl4 using C6H5O7Na3 as the reducing agent as well as the capping agent and then immobilized on the surface of the PPyox/GCE. The nanoparticles were characterized by UV-visible spectroscopy technique which confirmed the homogeneous formation of the bimetallic alloy nanoparticles. Transmission electron microscopy showed that the synthesized bimetallic nanoparticles were in the range of 20–50 nm. The electrochemical behaviour of anthracene at the PPyox/Ag-AuNPs/GCE with Ag: Au atomic ratio 25:75 (1:3) exhibited a higher electrocatalytic effect compared to that observed when GCE was modified with each constituent of the composite (i.e., PPyox, Ag-AuNPs) and bare GCE. A linear relationship between anodic current and anthracene concentration was attained over the range of 3.0 × 10−6 to 3.56 × 10−4 M with a detection limit of 1.69 × 10−7 M. The proposed method was simple, less time consuming and showed a high sensitivity. PMID:22163419

  18. Kinetic selection between organogel fibers and nano-ribbons of 2,3-didecyloxy-9,10-bisphenylethynyl-anthracene.

    PubMed

    Kao, Min-Tzu; Schäfer, Christian; Raffy, Guillaume; Del Guerzo, André

    2012-11-01

    A novel organogelator, DDPEA (2,3-didecyloxy-9,10-bisphenylethynyl-anthracene), displays a very unusual polymorphism upon self-assembly. The fluorescence resulting from J-aggregates reveals that the readily formed DDPEA gel evolves into another more stable state within four hours. Confocal fluorescence microscopy shows that this kinetic metastable gel-state is constituted of nanofibers, while the thermodynamically stable state is constituted of a dispersion of nano-ribbons or -crystals. Nano-fibers or nano-ribbons can be selected upon trapping the states by drying.

  19. Solubility of anthracene in ternary 2-alkoxyethanol + cyclohexane + heptane and 2-alkoxyethanol + cyclohexane + 2,2,4-trimethylpentane solvent mixtures

    SciTech Connect

    Deng, T.; Childress, S.D.; Fina, K.M. de; Hernandez, C.E.; Roy, L.E.; Sharp, T.L.; Acree, W.E. Jr.

    1999-03-01

    Experimental solubilities are reported for anthracene dissolved in ternary 2-ethoxyethanol + cyclohexane + heptane, 2-ethoxyethanol + cyclohexane + 2,2,4-trimethylpentane, 2-butoxyethanol + cyclohexane + heptane, and 2-butoxyethanol + cyclohexane + 2,2,4-trimethylpentane solvent mixtures at 25 C. Nineteen compositions were studied for each of the four solvent systems. Results of these measurements are used to test the predictive ability of the ternary solvent form of the combined NIMS/Redlich-Kister equation. Computations showed that the model predicted the observed solubility behavior to within an overall average absolute deviation of about 1.42%.

  20. Linear acene derivatives - New routes to pentacene and naphthacene and the first synthesis of a triptycene with two anthracene moieties

    NASA Technical Reports Server (NTRS)

    Luo, Jihmei; Hart, Harold

    1987-01-01

    The cycloaddition of o-xylylene to arene 1,4-endoxides was used to construct linear arene derivatives. An analogous sequence but with naphthalene 1,4-endoxides gave naphthacenes. Dehydration of the di adducts from 4 and anthracene 1,4:5,8-diendoxides gave a mixture of 5,9,14,18- and 5,8,15,18-tetrahydroheptacenes 3 and 9. The previously unknown triptycene 2 was synthesized from 5,14-dihydropentacene, an intermediate in the new pentacene synthesis, in three steps and 29 percent overall yield.

  1. Mutagenicity and tumorigenicity of the four enantiopure bay-region 3,4-diol-1,2-epoxide isomers of dibenz[a,h]anthracene.

    PubMed

    Chang, Richard L; Wood, Alexander W; Huang, Mou Tuan; Xie, Jian Guo; Cui, Xiao Xing; Reuhl, Kenneth R; Boyd, D R; Lin, Yong; Shih, Weichung Joe; Balani, Suresh K; Yagi, Haruhiko; Jerina, Donald M; Conney, Allan H

    2013-09-01

    Each enantiomer of the diastereomeric pair of bay-region dibenz[a,h]anthracene 3,4-diol-1,2-epoxides in which the benzylic 4-hydroxyl group and epoxide oxygen are either cis (isomer 1) or trans (isomer 2) were evaluated for mutagenic activity. In strains TA 98 and TA 100 of Salmonella typhimurium, the diol epoxide with (1S,2R,3S,4R) absolute configuration [(-)-diol epoxide-1] had the highest mutagenic activity. In Chinese hamster V-79 cells, the diol epoxide with (1R,2S,3S,4R) absolute configuration [(+)-diol epoxide-2] had the highest mutagenic activity. The (1R,2S,3R,4S) diol epoxide [(+)-diol epoxide-1] also had appreciable activity, whereas the other two bay-region diol epoxide enantiomers had very low activity. In tumor studies, the (1R,2S,3S,4R) enantiomer was the only diol epoxide isomer tested that had strong activity as a tumor initiator on mouse skin and in causing lung and liver tumors when injected into newborn mice. This stereoisomer was about one-third as active as the parent hydrocarbon, dibenz[a,h]anthracene as a tumor initiator on mouse skin; it was several-fold more active than dibenz[a,h]anthracene as a lung and liver carcinogen when injected into newborn mice. (-)-(3R,4R)-3β,4α-dihydroxy-3,4-dihydro-dibenz[a,h]anthracene [(-)-3,4-dihydrodiol] was slightly more active than dibenz[a,h]anthracene as a tumor initiator on mouse skin, whereas (+)-(3S,4S)-3α,4β-dihydroxy-3,4-dihydro-dibenz[a,h]anthracene [(+)-3,4-dihydrodiol] had only very weak activity. The present investigation and previous studies with the corresponding four possible enantiopure bay-region diol epoxide enantiomers/diastereomers of benzo[a]pyrene, benz[a]anthracene, chrysene, benzo[c]phenanthrene, dibenz[c,h]acridine, dibenz[a,h]acridine and dibenz[a,h]anthracene indicate that the bay-region diol epoxide enantiomer with [R,S,S,R] absolute stereochemistry has high tumorigenic activity on mouse skin and in newborn mice.

  2. Chemical insight from density functional modeling of molecular adsorption: Tracking the bonding and diffusion of anthracene derivatives on Cu(111) with molecular orbitals

    SciTech Connect

    Wyrick, Jonathan; Bartels, Ludwig; Einstein, T. L.

    2015-03-14

    We present a method of analyzing the results of density functional modeling of molecular adsorption in terms of an analogue of molecular orbitals. This approach permits intuitive chemical insight into the adsorption process. Applied to a set of anthracene derivates (anthracene, 9,10-anthraquinone, 9,10-dithioanthracene, and 9,10-diselenonanthracene), we follow the electronic states of the molecules that are involved in the bonding process and correlate them to both the molecular adsorption geometry and the species’ diffusive behavior. We additionally provide computational code to easily repeat this analysis on any system.

  3. Chemical insight from density functional modeling of molecular adsorption: Tracking the bonding and diffusion of anthracene derivatives on Cu(111) with molecular orbitals

    NASA Astrophysics Data System (ADS)

    Wyrick, Jonathan; Einstein, T. L.; Bartels, Ludwig

    2015-03-01

    We present a method of analyzing the results of density functional modeling of molecular adsorption in terms of an analogue of molecular orbitals. This approach permits intuitive chemical insight into the adsorption process. Applied to a set of anthracene derivates (anthracene, 9,10-anthraquinone, 9,10-dithioanthracene, and 9,10-diselenonanthracene), we follow the electronic states of the molecules that are involved in the bonding process and correlate them to both the molecular adsorption geometry and the species' diffusive behavior. We additionally provide computational code to easily repeat this analysis on any system.

  4. Chemical insight from density functional modeling of molecular adsorption: Tracking the bonding and diffusion of anthracene derivatives on Cu(111) with molecular orbitals.

    PubMed

    Wyrick, Jonathan; Einstein, T L; Bartels, Ludwig

    2015-03-14

    We present a method of analyzing the results of density functional modeling of molecular adsorption in terms of an analogue of molecular orbitals. This approach permits intuitive chemical insight into the adsorption process. Applied to a set of anthracene derivates (anthracene, 9,10-anthraquinone, 9,10-dithioanthracene, and 9,10-diselenonanthracene), we follow the electronic states of the molecules that are involved in the bonding process and correlate them to both the molecular adsorption geometry and the species' diffusive behavior. We additionally provide computational code to easily repeat this analysis on any system.

  5. Synthesis and Luminescent Chemosensory Behavior of N,N'-bis(p-aminophenyl)-1,5-bis(p-(tetraethyleneglycoloxy)phenyl)anthracene-2,3,6,7-tetracarboxyl bisimide

    NASA Technical Reports Server (NTRS)

    Ilhan, Faysal; Tyson, Daniel S.; Meador, Michael A.

    2004-01-01

    We have utilized the photoenolization reaction of a dibenzoyl-p-xylene derivative to synthesize two new, highly substituted anthracene-based molecules. ABI-NO2 and ABI-NH2 maintained photostability with longer wavelength absorption and emission spectra as compared to unsubstituted anthracene. Conversion of the periphery nitro groups to amines created an internal photoinduced electron transfer scenario that quenched the luminescence of ABI-NH2. Reversible or irreversible reaction of the attached amines resulted in fluorescence recovery. Sensitivity, of ABI-NH2 and other potential derivatives, to toxic chemicals may prove useful for early detection systems.

  6. Effects of anthracene on filtration rates, antioxidant defense system, and redox proteomics in the Mediterranean clam Ruditapes decussatus (Mollusca: Bivalvia).

    PubMed

    Sellami, Badreddine; Khazri, Abdelhafidh; Louati, Héla; Dellali, Mohamed; Driss, Mouhamed Ridha; Aïssa, Patricia; Mahmoudi, Ezzeddine; Hamouda, Beyrem; Coelho, Ana Varela; Sheehan, David

    2015-07-01

    This study aimed at analyzing the impact of a toxic polyaromatic hydrocarbon (PAH), anthracene (ANT), on Ruditapes decussatus collected from a Tunisian coastal lagoon (Bizerte Lagoon). Filtration rates, several antioxidant enzymes--superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione transferase (GST)--as well as indices of protein oxidation status were determined in various tissues of this bivalve. Specimens were exposed to 100 μg/L of ANT for 2 days. ANT levels were evaluated using HPLC and were detected in the gill and digestive gland at different amounts. ANT exposure altered the behavior of bivalves by changing the siphon movement and decreasing filtration rate significantly. The enzymatic results indicated that ANT exposure affected the oxidative stress status of the gills of R. decussatus. In addition, modification of proteins was detected in the gills using redox proteomics after ANT treatment. Three protein spots were successfully identified by matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry (MALDI-TOF-MS). These proteins can be roughly related to muscle contraction function. In contrast, no significant modification of enzymatic and protein responses was detected in the digestive gland after ANT treatment. These data demonstrate that combined behavioral and biochemical analyses are a powerful tool to provide valuable insights into possible mechanisms of toxicity of anthracene in R. decussatus. Additionally, the results highlight the potential of the gill as a valuable candidate for investigating PAH toxicity.

  7. Infrared Spectroscopy of Matrix-Isolated Polycyclic Aromatic Hydrocarbon Cations. 3; The Polyacenes Anthracene, Tetracence, and Pentacene

    NASA Technical Reports Server (NTRS)

    Hudgins, D. M.; Allamandola, L. J.

    1995-01-01

    Gaseous, ionized polycyclic aromatic hydrocarbons (PAHS) are thought to be responsible for a very common family of interstellar infrared emission bands. Unfortunately, very little infrared spectroscopic data are available on ionized PAHS. Here we present the near- and mid-infrared spectra of the polyacene cations anthracene, tetracene, and pentacene. We also report the vibrational frequencies and relative intensities of the pentacene anion. The cation bands corresponding to the CC modes are typically about 10-20 times more intense than those of the CH out-of-plane bending vibrations. For the cations the CC stretching and CH in-plane bending modes give rise to bands which are an order of magnitude stronger than for the neutral species, and the CH out-of-plane bends produce bands which are 3-20 times weaker than in the neutral species. This behavior is similar to that found for most other PAH cations. The most intense PAH cation bands fall within the envelopes of the most intense interstellar features. The strongest absorptions in the polyacenes anthracene, tetracene, and pentacene tend to group around 1400/cm (between about 1340 and 1500/cm) and near 1180/cm, regions of only moderate interstellar emission. These very strong polyacene bands tend to fall in gaps in the spectra of the other PAH cations studied to date suggesting that while PAHs with polyacene structures may contribute to specific regions of the interstellar emission spectra, they are not dominant members of the interstellar PAH family.

  8. Infrared Spectroscopy of Matrix-Isolated Polycyclic Aromatic Hydrocarbon Cations. 3. The Polyacenes Anthracene, Tetracene, and Pentacene

    NASA Technical Reports Server (NTRS)

    Hudgins, D. M.; Allamandola, L. J.

    1995-01-01

    Gaseous, ionized Polycyclic Aromatic Hydrocarbons (PAH's) are thought to be responsible for a very common family of interstellar infrared emission bands. Unfortunately, very little infrared spectroscopic data are available on ionized PAH's. Here we present the near- and mid-infrared spectra of the polyacene cations anthracene, tetracene, and pentacene. We also report the vibrational frequencies and relative intensities of the pentacene anion. The cation bands corresponding to the CC modes are typically about 10-20 times more intense than those of the CH out-of-plane bending vibrations. For the cations the CC stretching and CH in-plane bending modes give rise to bands which are an order of magnitude stronger than for the neutral species, and the CH out-of-plane bends produce bands which are 3-20 times weaker than in the neutral species. This behavior is similar to that found for most other PAH cations. The most intense PAH cation bands fall within the envelopes of the most intense interstellar features. The strongest absorptions in the polyacenes anthracene, tetracene, and pentacene tend to group around 1400 / cm (between about 1340 and 1500 / cm) and near 1180 /cm, regions of only moderate interstellar emission. These very strong polyacene bands tend to fall in gaps in the spectra of the other PAH cations studied to date suggesting that while PAHs with polyacene structures may contribute to specific regions of the interstellar emission spectra, they are not dominant members of the interstellar PAH family.

  9. Bacteria capable of degrading anthracene, phenanthrene, and fluoranthene as revealed by DNA based stable-isotope probing in a forest soil.

    PubMed

    Song, Mengke; Jiang, Longfei; Zhang, Dayi; Luo, Chunling; Wang, Yan; Yu, Zhiqiang; Yin, Hua; Zhang, Gan

    2016-05-01

    Information on microorganisms possessing the ability to metabolize different polycyclic aromatic hydrocarbons (PAHs) in complex environments helps in understanding PAHs behavior in natural environment and developing bioremediation strategies. In the present study, stable-isotope probing (SIP) was applied to investigate degraders of PAHs in a forest soil with the addition of individually (13)C-labeled phenanthrene, anthracene, and fluoranthene. Three distinct phylotypes were identified as the active phenanthrene-, anthracene- and fluoranthene-degrading bacteria. The putative phenanthrene degraders were classified as belonging to the genus Sphingomona. For anthracene, bacteria of the genus Rhodanobacter were the putative degraders, and in the microcosm amended with fluoranthene, the putative degraders were identified as belonging to the phylum Acidobacteria. Our results from DNA-SIP are the first to directly link Rhodanobacter- and Acidobacteria-related bacteria with anthracene and fluoranthene degradation, respectively. The results also illustrate the specificity and diversity of three- and four-ring PAHs degraders in forest soil, contributes to our understanding on natural PAHs biodegradation processes, and also proves the feasibility and practicality of DNA-based SIP for linking functions with identity especially uncultured microorganisms in complex microbial biota. PMID:26808242

  10. N-[(E)-Anthracen-9-yl­methyl­idene]-3,4-dimethyl-1,2-oxazol-5-amine

    PubMed Central

    Asiri, Abdullah M.; Al-Youbi, Abdulrahman O.; Khan, Salman A.; Tahir, M. Nawaz

    2011-01-01

    In the title compound, C20H16N2O, an intra­molecular C—H⋯N forms an S(6) ring motif. In the crystal, the mol­ecules are stacked with their anthracene ring planes in sheets along [100]. PMID:22199959

  11. INDUCTION OF DNA ADDUCTS, TUMORS, AND KI-RAS ONCOGENE MUTATIONS IN STRAIN A/J MOUSE LUNG BY IP. ADMINISTRATION OF DIBENZ[A,H]ANTHRACENE

    EPA Science Inventory

    Induction of DNA adducts, tumors, and Ki-ras oncogene mutations in strain AlJ mouse lung by ip. administration of dibenz[a,h]anthracene

    Previous studies of polycyclic aromatic hydrocarbon (P AH) induced lung tumors in the strain NJ mouse model system have demonstrated qua...

  12. Improving Photovoltaic Performance of the Linear A-Ar-A-type Small Molecules with Diketopyrropyrrole Arms by Tuning the Linkage Position of the Anthracene Core.

    PubMed

    Duan, Xiongwei; Xiao, Manjun; Chen, Jianhua; Wang, Xiangdong; Peng, Wenhong; Duan, Linrui; Tan, Hua; Lei, Gangtie; Yang, Renqiang; Zhu, Weiguo

    2015-08-26

    Two isomeric A-Ar-A-type small molecules of DPP2An(9,10) and DPP2An(2,6), were synthesized with two acceptor arms of diketopyrropyrroles (DPP) and a planar aryl hydrocarbon core of the different substituted anthracene (An), respectively. Their thermal stability, crystallinity, optoelectronic, and photovoltaic performances were investigated. Significantly red-shifted absorption profile and higher HOMO level were observed for the DPP2An(2,6) with 2,6-substituted anthracene relative to the DPP2An(9,10) with 9,10-substituted anthracene, as the former exhibited better planarity and a larger conjugate system. As a result, the solution-processing solar cells based on DPP2An(2,6) and PC71BM (w/w,1:1) displayed remarkably increased power conversion efficiency of 5.44% and short-circuit current density (Jsc) of 11.90 mA/cm(2) under 1% 1,8-diiodooctane additive. The PCE and Jsc values were 3.7 and 2.9 times those of the optimized DPP2An(9,10)-based cells, respectively. This work demonstrates that changing the linkage position of the anthracene core in the A-Ar-A-type SMs can strongly improve the photovoltaic properties in organic solar cells.

  13. DIELDRIN INDUCES CYTOSOLIC 7,12-[3H-]DIMETHYLBENZ[A]ANTHRACENE BINDING BUT NOT MULTIDRUG RESISTANCE PROTEINS IN RAINBOW TROUT LIVER.

    EPA Science Inventory

    Previously it was demonstrated that biliary excretion of a single dose of [14C]dieldrin or [3H]7,12-dimethylbenz[a]anthracene (DMBA) was stimulated up to 700% and 300%, respectively, in rainbow trout fed 0.3-0.4 mg dieldrin/kg/d for 9-12 wk. This was not explained by increased ac...

  14. Mass spectrometric analysis of 7-sulfoxymethyl-12-methylbenz[a]anthracene and related electrophilic polycyclic aromatic hydrocarbon metabolites.

    PubMed

    Lehner, Andreas F; Horn, Jamie; Flesher, James W

    2004-11-01

    The Meso-region theory of polycyclic aromatic hydrocarbon (PAH) carcinogenesis predicts that the development of pronounced carcinogenicity depends on the introduction of a good leaving group on alkyl side-chains attached to the exceptionally reactive meso-anthracenic or L-region positions of PAHs. Thus, the first step in carcinogenesis by methylated PAHs such as 7,12-dimethylbenz[a]anthracene (DMBA) would be the hydroxylation of the L-region methyl groups, particularly the 7-methyl group. The second would be the formation of a metabolite, e.g. a sulfate ester, which is expected to be a good leaving group capable of generating a highly reactive benzylic carbocation. 7-Hydroxymethyl-12-methylbenz[a]anthracene (7-HMBA) is a metabolite of DMBA, and sulfation of 7-HMBA to a 7-sulfoxymethyl metabolite (7-SMBA) is a known Phase II metabolic process designed to facilitate excretion, but actually enabling more destructive side-reactions. These side-reactions occur with generation of an electrophilic 7-methylene carbonium ion, and/or by in vivo halide exchange to provide neutral side-products more capable of entering cells, especially those of DMBA target tissues. Electrospray ionization mass spectrometry (MS) enabled us to visualize 7-SMBA as an intact m/z 351 conjugate anion by negative mode, and as a released m/z 255 carbonium ion by positive mode. Upon prolonged refrigeration, 7-SMBA accumulated an m/z 383 photooxide, which appeared capable of re-evolving the starting material as visualized by tandem quadrupole MS, or MS/MS. The 7-SMBA carbonium ion provided interpretable fragments when studied by fragment ion MS/MS, including those representing the loss of up to several protons. Subtle differences in this property were encountered upon perturbing 7-SMBA, either by warming it at 37 degrees C for 2 h or by substituting the initial sulfoxy group with an iodo group. Side-reactions accounting for such proton losses are proposed, and are of interest whether they occur in the

  15. Mass spectrometric analysis of 7-sulfoxymethyl-12-methylbenz[a]anthracene and related electrophilic polycyclic aromatic hydrocarbon metabolites.

    PubMed

    Lehner, Andreas F; Horn, Jamie; Flesher, James W

    2004-11-01

    The Meso-region theory of polycyclic aromatic hydrocarbon (PAH) carcinogenesis predicts that the development of pronounced carcinogenicity depends on the introduction of a good leaving group on alkyl side-chains attached to the exceptionally reactive meso-anthracenic or L-region positions of PAHs. Thus, the first step in carcinogenesis by methylated PAHs such as 7,12-dimethylbenz[a]anthracene (DMBA) would be the hydroxylation of the L-region methyl groups, particularly the 7-methyl group. The second would be the formation of a metabolite, e.g. a sulfate ester, which is expected to be a good leaving group capable of generating a highly reactive benzylic carbocation. 7-Hydroxymethyl-12-methylbenz[a]anthracene (7-HMBA) is a metabolite of DMBA, and sulfation of 7-HMBA to a 7-sulfoxymethyl metabolite (7-SMBA) is a known Phase II metabolic process designed to facilitate excretion, but actually enabling more destructive side-reactions. These side-reactions occur with generation of an electrophilic 7-methylene carbonium ion, and/or by in vivo halide exchange to provide neutral side-products more capable of entering cells, especially those of DMBA target tissues. Electrospray ionization mass spectrometry (MS) enabled us to visualize 7-SMBA as an intact m/z 351 conjugate anion by negative mode, and as a released m/z 255 carbonium ion by positive mode. Upon prolonged refrigeration, 7-SMBA accumulated an m/z 383 photooxide, which appeared capable of re-evolving the starting material as visualized by tandem quadrupole MS, or MS/MS. The 7-SMBA carbonium ion provided interpretable fragments when studied by fragment ion MS/MS, including those representing the loss of up to several protons. Subtle differences in this property were encountered upon perturbing 7-SMBA, either by warming it at 37 degrees C for 2 h or by substituting the initial sulfoxy group with an iodo group. Side-reactions accounting for such proton losses are proposed, and are of interest whether they occur in the

  16. Chemistry of anthracene-acetylene oligomers XXV: on-surface chirality of a self-assembled molecular network of a fan-blade-shaped anthracene-acetylene macrocycle with a long alkyl chain.

    PubMed

    Tsuya, Takuya; Iritani, Kohei; Tahara, Kazukuni; Tobe, Yoshito; Iwanaga, Tetsuo; Toyota, Shinji

    2015-03-27

    An anthracene cyclic dimer with two different linkers and a dodecyl group was synthesized by means of coupling reactions. The calculated structure had a planar macrocyclic π core and a linear alkyl chain. Scanning tunneling microscopy observations at the 1-phenyloctane/graphite interface revealed that the molecules formed a self-assembled monolayer that consisted of linear striped bright and dark bands. In each domain, the molecular network consisted of either Re or Si molecules that differed in the two-dimensional chirality about the macrocyclic faces, which led to a unique conglomerate-type self-assembly. The molecular packing mode and the conformation of the alkyl chains are discussed in terms of the intermolecular interactions and the interactions between the molecules and the graphite surface with the aid of MM3 simulations of a model system.

  17. Comparative tumor-initiating activity of methylene-bridged and bay-region methylated derivatives of benz[a]anthracene and chrysene.

    PubMed

    Rice, J E; Jordan, K; Little, P; Hussain, N

    1988-12-01

    Polycyclic aromatic hydrocarbons (PAHs) with a methylene-bridge spanning the bay region are often detected in higher concentrations in the environment than PAHs which have a bay-region methyl substituent. The tumor-initiating activity of methylene-bridged bay-region derivatives of chrysene and benz[a]anthracene was evaluated on the skin of female CD-1 mice. 4,5-Methylenechrysene elicited twice as many tumors as chrysene at each of the doses tested. At total initiation doses of 1.5, 0.5 and 0.15 mumol/mouse 4,5-methylenechrysene gave rise to 8.5, 6.8 and 1.1 tumors/animal respectively. There was a 100% incidence of tumor-bearing mice at the two higher doses and a 65% incidence at the lowest dose. This methylene-bridged hydrocarbon was less tumorigenic than 5-methylchrysene at each dose tested. Animals treated with 1,12-methylenebenz[a]anthracene developed 7.6, 4.9 and 1.6 tumors/animal at total initiating doses of 4.0, 2.0 and 0.5 mumol/mouse. The incidence of tumor-bearing mice was 90% at the higher doses and 75% at the lowest dose tested. 12-Methylbenz[a]anthracene was more tumorigenic than the methylene-bridged derivative at each dose. The keto-derivative of 1,12-methylenebenz[a]anthracene did not display significant (P greater than 0.05) tumor-initiating activity at these dose levels. Results from these bioassays indicate that methylene-bridged bay-region derivatives of chrysene and benz[a]anthracene contribute to the overall genotoxicity of environmentally occurring PAHs.

  18. Continuous fluorescence microphotolysis of anthracene-labeled phospholipids in membranes. Theoretical approach of the simultaneous determination of their photodimerization and lateral diffusion rates.

    PubMed Central

    Ferrières, X; Lopez, A; Altibelli, A; Dupou-Cezanne, L; Lagouanelle, J L; Tocanne, J F

    1989-01-01

    Anthracene is a fluorescent and photoactivatable (dimerization) group which can be used for investigating the lateral distribution and dynamics of lipids in membranes. In fluorescence recovery after photobleaching or in microphotolysis experiments, and when using this fluorophore, the bleaching (or microphotolysis) step in the illuminated part of the membrane is in fact the sum of two antagonistic processes: fluorescence decay, which is due to dimerization of anthracene residues, and fluorescence recovery, which is due to a diffusion mediated exchange of bleached and unbleached particles between the illuminated and diffusion area in the membrane. Here, we propose a new mathematical algorithm that enables such a second-order reaction-diffusion process to be analyzed. After coupling a fluorescence recovery step to a microphotolysis step, this algorithm allows us to calculate the lateral diffusion coefficient D and the photodimerization constant K of anthracene-labeled lipids in membranes, two parameters which contribute to the understanding of the fluidity of the lipid phase in membranes. This algorithm also provides us with a complete description of the anthracene-labeled molecules distribution in the illuminated and diffusion area, at any time of the experiment. The fluorescence recovery after microphotolysis procedure we propose was tested with an anthracene-labeled phosphatidylcholine inserted in egg-phosphatidylcholine multilayers, in monolayers adsorbed onto alkylated glass surfaces and in the plasma membrane of Chinese hamster ovary cells. It is shown that this procedure can also be used to evaluate the important parameters of probe mobile fraction and to determine the relative size of the illuminated and diffusion areas. This will enable membranes to be explored in terms of microdomains and/or macrodomains. PMID:2765646

  19. Solubility of anthracene in binary alkane + methyl tert-butyl ether solvent mixtures at 298.15 K

    SciTech Connect

    McHale, M.E.R.; Kauppila, A.S.M.; Acree, W.E. Jr.

    1996-09-01

    Experimental solubilities are reported for anthracene dissolved in seven binary mixtures containing methyl tert-butyl ether (also called 2-methoxy-2-methylpropane) with hexane, heptane, octane, cyclohexane, methylcyclohexane, 2,2,4-trimethylpentane, and tert-butylcyclohexane (also called (1,1-dimethylethyl)-cyclohexane) at 25 C. Results of these measurements are used to test two mathematical representations based upon the combined nearly ideal binary solvent (NIBS)/Redlich-Kister equation and modified Wilson model. For the seven systems studied, both equations were found to provide an accurate mathematical representation of the experimental data, with an overall average absolute deviation between measured and calculated values being on the order of 0.5%.

  20. Chemopreventive potential of Tribulus terrestris against 7,12- dimethylbenz (a) anthracene induced skin papillomagenesis in mice.

    PubMed

    Kumar, Manish; Soni, Anil Kumar; Shukla, Shalini; Kumar, Ashok

    2006-01-01

    In the present investigation, the chemopreventive potential of aqueous extracts of the root and fruit of Tribulus terrestris (an Ayurvedic medicinal plant) on 7, 12 - dimethylbenz (a) anthracene (DMBA) induced papillomagenesis in male Swiss albino mice was studied. A significant reduction in tumor incidence, tumor burden and cumulative number of papillomas was observed, along with a significant increase in average latent period in mice treated orally with Tribulus terrestris suspension continuously at pre, peri and post-initiation stages of papillomagenesis as compared to the control group treated with DMBA and croton oil alone. Treatment with Tribulus terrestris suspension by oral gavage for 7 days resulted in a significant increase in the reduced glutathione content in the liver (P< 0.001 for both root and fruit extracts). Conversely, lipid peroxidation levels were significantly decreased (P< 0.001).

  1. Synthesis and Enantiomeric Recognition Studies of Optically Active Pyridino-Crown Ethers Containing an Anthracene Fluorophore Unit.

    PubMed

    Szemenyei, Balázs; Móczár, Ildikó; Pál, Dávid; Kocsis, Ivett; Baranyai, Péter; Huszthy, Péter

    2016-07-01

    Novel enantiopure pyridino-18-crown-6 ether-based sensor molecules containing an anthracene fluorophore unit were synthesized. Their enantiomeric recognition abilities toward the enantiomers of 1-phenylethylamine hydrogen perchlorate (PhEt), 1-(1-naphthyl)ethylamine hydrogen perchlorate (NapEt), phenylglycine methyl ester hydrogen perchlorate (PhgOMe), and phenylalanine methyl ester hydrogen perchlorate (PheOMe) were examined in acetonitrile using fluorescence spectroscopy. The sensor molecules showed appreciable enantiomeric recognition toward the enantiomers of NapEt, PhEt, and PhgOMe. The highest enantioselectivity was found in the case of crown ether containing isobutyl groups in the macroring and the enantiomers of NapEt. Chirality 28:562-568, 2016. © 2016 Wiley Periodicals, Inc.

  2. Design, Synthesis, and Biological Evaluation of a Series of Anthracene-9,10-dione Dioxime β-Catenin Pathway Inhibitors.

    PubMed

    Soldi, Raffaella; Horrigan, Stephen K; Cholody, Marek W; Padia, Janak; Sorna, Venkataswamy; Bearss, Jared; Gilcrease, Glynn; Bhalla, Kapil; Verma, Anupam; Vankayalapati, Hariprasad; Sharma, Sunil

    2015-08-13

    The Wnt/β-catenin signaling pathway plays a vital role in cell growth, the regulation, cell development, and the differentiation of normal stem cells. Constitutive activation of the Wnt/β-catenin signaling pathway is found in many human cancers, and thus, it is an attractive target for anticancer therapy. Specific inhibitors of this pathway have been keenly researched and developed. Cell based screening of compounds library, hit-to-lead optimization, computational and structure-based design strategies resulted in the design and synthesis of a series of anthracene-9,10-dione dioxime series of compounds demonstrated potent inhibition of β-catenin in vitro (IC50 < 10 nM, 14) and the growth of several cancer cell lines. This article discusses the potential of inhibiting the Wnt/β-catenin signaling pathway as a therapeutic approach for cancer along with an overview of the development of specific inhibitors. PMID:26182238

  3. Fate of 7,12-dimethylbenz(a)anthracene absorbed from the rat intestine and transported in chylomicrons

    SciTech Connect

    Lindstrom, M.B.; Barrowman, J.A.; Borgstrom, B.

    1987-04-01

    Chylomicrons obtained from the thoracic duct of rats fed (/sup 3/H)7,12-dimethylbenz(a)anthracene (DMBA), a polycyclic aromatic hydrocarbon, were infused intravenously into rats with bile fistulas. Over 17 hr, 55.9 +/- 3.2% (mean +/- SEM) of the radioactivity was recovered in bile and 6.7 +/- 0.5% in urine. Minor amounts were deposited in liver, kidneys and epididymal fat pads. Injection of DMBA in ethanolic solution gave a similar pattern, while biliary DMBA metabolites resulted in higher recovery in urine and lower recovery in fat. In conclusion, the major part of chylomicron DMBA is rapidly excreted via the biliary route, while a fraction is probably retained in adipose tissue.

  4. Influence of chronic prolactin suppression during puberty on the development of dimethylbenz(a)anthracene-induced mammary tumors (41163). [Rats

    SciTech Connect

    Cohen, L.A.

    1981-06-01

    In order to assess the effect of early prolactin suppression on the subsequent development of dimethylbenz(a)anthracene (DMBA)-induced mammary cancers, the dopamine agonist, CB-154, was chronically administered to female Sprague-Dawley rats from Day 35 to Day 50 of age. DMBA was then administered and tumor development assessed over a 25-week period. It was found that animals treated with CB-154 exhibited decreased tumor incidence, a longer latent period, and fewer tumors/animal, when compared to vehicle controls. These results are consistent with the hypothesis that the sensitivity of the mammary gland to polycyclic aromatic hydrocarbon (PAH) carcinogenesis is determined by the level of differentiation of the gland at the time of carcinogen administration. Accordingly, perturbations in prolactin secretion patterns, early in life, may accelerate or retard the differentiation of the mammary gland thereby rendering it less susceptible to the carcinogenic effects of PAH.

  5. 7,12-dimethylbenz(a)anthracene-induced modulation of cytokines involved in cytotoxic t lymphocyte induction

    SciTech Connect

    House, R.V.; Pallardy, M.J.; Burleson, G.R.; Dean, J.H.

    1988-01-01

    Murine lymphocytes were exposed to the carcinogenic polycyclic aromatic hydrocarbon 7,12-dimethylbenz(a)anthracene (DMBA) and several cytokines were measured. Production of interleukin-1 by macrophages, interleukin-2 by EL-4 thymoma, and gamma interferon by activated splenic lymphocytes were not affected by DMBA. However, interleukin-5 (also known as T cell replacing factor) was significantly suppressed by DMBA. Cloned cytotoxic T lymphocyte activity was inhibited in a dose-dependent manner by DMBA and the suppression was significantly enhanced by addition of beta or gamma interferon. The results support the hypothesis that, rather than acting as a non-specific inhibitor of lymphocyte proliferation, DMBA-induced suppression of antigen-specific cytolysis is a mechanism directed against highly-specific cellular targets in the immune process.

  6. Induction of hepatic tumors with 7,12-dimethylbenz(a)anthracene in two species of viviparous fishes (genus Poeciliopsis)

    SciTech Connect

    Schultz, M.E.; Schultz, R.J.

    1982-04-01

    Liver neoplasms were induced in two species of viviparous fishes, Poeciliopsis lucida and P. monacha, by repeated short-term exposures to an aqueous suspension of 5 ppm 7,12-dimethylbenz(a)anthracene (DMBA). Predominantly hepatocellular neoplasms developed in 47 out of 106 fish surviving the period allowed for tumor development, 6-9 months after initial exposure to DMBA. The use of short-term exposure periods of 6 hr in young fish and up to 20 hr in adults reduced stress and mortalities caused by the toxicity of DMBA at 5 ppm. A lower concentration of DMBA, 0.25 ppm, failed to induce tumors in any of the surviving 230 of 295 young fish administered repeated 20-hr exposures. This study shows for the first time that DMBA is carcinogenic to fish.

  7. Localization of gamma-glutamyl transpeptidase in hamster buccal pouch epithelium treated with 7,12-dimethylbenz(a)anthracene

    SciTech Connect

    Solt, D.B.

    1981-07-01

    The utility of gamma-glutamyl transpeptidase (GGT) was explored as a histochemical marker for chemical carcinogenesis in hamster buccal pouch mucosa. One or both buccal pouches of 18 noninbred male Syrian golden hamsters were treated topically with 0.5% 7,12-dimethylbenz(a)anthracene (DMBA) in mineral oil over 16 weeks to produce numerous epithelial lesions at various stages of neoplastic development. Both buccal pouches of 4 control animals were similarly treated with mineral oil alone. GGT activity was not detectable in untreated pouches or pouches treated with mineral oil alone. With this technique, multiple discrete GGT-stained areas were visible in wholemounts prepared at 1 and 6 weeks after the final application of DMBA. The experimental results were consistent with the hypothesis that the early GGT-stained cell populations are preneoplastic in nature.

  8. Isolation of novel benzo[a]anthracene-degrading microorganisms and continuous bioremediation in an expanded-bed bioreactor.

    PubMed

    Rosales, E; Pérez-Paz, A; Vázquez, X; Pazos, M; Sanromán, M A

    2012-06-01

    In the present work, several samples from lab waste containers polluted with polycyclic aromatic hydrocarbons (PAHs) and heavy metals were investigated as potential sources of PAH-degrading microorganisms. After isolating, two fungal strains were selected as the best degrading microorganisms. Genetic identification by sequencing was carried out and they were identified as Trichoderma longibrachiatum and Byssochlamys spectabilis. Their degradation ability was determined in liquid cultures with 100 μM of benzo[a]anthracene. T. longibrachiatum cultures showed highest degradation values (around 97%) after 9 days, furthermore in a second batch the time was reduced to 6 days. To analyse the viability of industrial application, a continuous treatment in an expanded-bed bioreactor was developed operating at different residence times with T. longibrachiatum immobilised on cubes of nylon sponge. It is noticeable that the bioreactor working in continuous mode was able to operate without operational problems and attaining high degradation levels depending on the residence time.

  9. Synthesis and Enantiomeric Recognition Studies of Optically Active Pyridino-Crown Ethers Containing an Anthracene Fluorophore Unit.

    PubMed

    Szemenyei, Balázs; Móczár, Ildikó; Pál, Dávid; Kocsis, Ivett; Baranyai, Péter; Huszthy, Péter

    2016-07-01

    Novel enantiopure pyridino-18-crown-6 ether-based sensor molecules containing an anthracene fluorophore unit were synthesized. Their enantiomeric recognition abilities toward the enantiomers of 1-phenylethylamine hydrogen perchlorate (PhEt), 1-(1-naphthyl)ethylamine hydrogen perchlorate (NapEt), phenylglycine methyl ester hydrogen perchlorate (PhgOMe), and phenylalanine methyl ester hydrogen perchlorate (PheOMe) were examined in acetonitrile using fluorescence spectroscopy. The sensor molecules showed appreciable enantiomeric recognition toward the enantiomers of NapEt, PhEt, and PhgOMe. The highest enantioselectivity was found in the case of crown ether containing isobutyl groups in the macroring and the enantiomers of NapEt. Chirality 28:562-568, 2016. © 2016 Wiley Periodicals, Inc. PMID:27349957

  10. Multiple effects of anthracene-9-carboxylic acid on the TMEM16B/anoctamin2 calcium-activated chloride channel.

    PubMed

    Cherian, O Lijo; Menini, Anna; Boccaccio, Anna

    2015-04-01

    Ca(2+)-activated Cl(-) currents (CaCCs) play important roles in many physiological processes. Recent studies have shown that TMEM16A/anoctamin1 and TMEM16B/anoctamin2 constitute CaCCs in several cell types. Here we have investigated for the first time the extracellular effects of the Cl(-) channel blocker anthracene-9-carboxylic acid (A9C) and of its non-charged analogue anthracene-9-methanol (A9M) on TMEM16B expressed in HEK 293T cells, using the whole-cell patch-clamp technique. A9C caused a voltage-dependent block of outward currents and inhibited a larger fraction of the current as depolarization increased, whereas the non-charged A9M produced a small, not voltage dependent block of outward currents. A similar voltage-dependent block by A9C was measured both when TMEM16B was activated by 1.5 and 13μM Ca(2+). However, in the presence of 1.5μM Ca(2+) (but not in 13μM Ca(2+)), A9C also induced a strong potentiation of tail currents measured at -100mV after depolarizing voltages, as well as a prolongation of the deactivation kinetics. On the contrary, A9M did not produce potentiation of tail currents, showing that the negative charge is required for potentiation. Our results provide the first evidence that A9C has multiple effects on TMEM16B and that the negative charge of A9C is necessary both for voltage-dependent block and for potentiation. Future studies are required to identify the molecular mechanisms underlying these complex effects of A9C on TMEM16B. Understanding these mechanisms will contribute to the elucidation of the structure and functional properties of TMEM16B channels.

  11. Substituent position dictates the intercalative DNA-binding mode for anthracene-9,10-dione antitumor drugs.

    PubMed

    Tanious, F A; Jenkins, T C; Neidle, S; Wilson, W D

    1992-11-24

    Molecular modeling studies [Islam, S.A., Neidle, S., Gandecha, B.M., Partridge, M., Patterson, L.H., & Brown, J.R. (1985) J. Med. Chem. 28, 857-864] have suggested that anthracene-9,10-dione (anthraquinone) derivatives substituted at the 1,4 and 1,8 positions with-NH(CH2)2NH(CH2CH3)2+ side chains intercalate with DNA with both substituents in the same groove (classical intercalation) while a similarly substituted 1,5 derivative intercalates in a threading mode with one side chain in each groove. Modeling studies also suggested that anthracene-9,10-dione (anthraquinone) derivatives substituted at the 2,6 positions with -NHCO(CH2)R (where R is a cationic group) should bind to DNA by the threading mode, and several such derivatives have been synthesized [Agbandjie, M., Jenkins, T.C., McKenna, R., Reszka, A., & Neidle, S. (1992) J. Med. Chem. 35, 1418-1429]. We have conducted stopped-flow kinetics association and dissociation experiments on the interaction of these anthraquinones with calf thymus DNA and with DNA polymers with alternating AT and GC base pairs to experimentally determine the binding mode and how the threading mode affects intercalation rates relative to similarly substituted classical intercalators. The binding modes, determined by analysis of relative rates, energies of activation, and effects of salt concentration on association and dissociation rate constants, agree completely with the modes predicted by molecular modeling methods. Association and dissociation rate constants for the threading mode are approximately a factor of 10 lower than constants for the classical intercalation mode, and the two modes, thus, have similar binding constants. Variations in rate constants for changes in cationic substituents at the 2 and 6 positions of the anthraquinone ring were surprisingly small.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. [6]-Shogaol, a Novel Chemopreventor in 7,12-Dimethylbenz[a]anthracene-induced Hamster Buccal Pouch Carcinogenesis.

    PubMed

    Kathiresan, Suresh; Govindhan, Annamalai

    2016-04-01

    Oral cancer is a major cause of morbidity and mortality in developing countries. Despite advances in chemotherapy for the cancer management, the survival rate has not yet been improved. Dietary nutrient has been receiving a lot of attention and interest in the chemotherapeutic development. [6]-Shogaol is a major bioactive compound identified in ginger that possesses many pharmacological properties. The aim of the present study is to investigate the effect of [6]-shogaol on 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch (HBP) carcinogenesis. Oral squamous cell carcinoma induced in HBP by painting with 0.5% 7,12-dimethylbenz(a)anthracene (DMBA), thrice in a week for 16 weeks. We observed 100% tumour incidence, decreased levels of lipid peroxidation, antioxidant, and phase II detoxification enzymes (GST, GR and GSH) in DMBA-induced hamsters. Further, enhanced activity of phase I enzymes (cytochrome p450 and b5) and over-expression of mutant p53, Bcl-2 and decreased expression of wild type p53 and Bax were noticed in DMBA-induced hamsters. Our results indicated that [6]-shogaol (10, 20 and 40 mg/kg body weight) treated with DMBA-painted hamsters, considerably reversed tumour incidence, improved antioxidant status, phase II detoxification enzymes, and also inhibit lipid peroxidation and phase I enzymes. Moreover, [6]-shogaol inhibits mutant p53 and Bcl-2 expression and significantly restored normal p53, Bax levels. Thus, we concluded that [6]-shogaol prevents DMBA-induced HBP carcinogenesis through its antioxidant as well as modulating apoptotic signals. PMID:26840796

  13. Unique anisotropic optical properties of a highly stable metal-organic framework based on trinuclear iron(iii) secondary building units linked by tetracarboxylic linkers with an anthracene core.

    PubMed

    Vinogradov, A V; Milichko, V A; Zaake-Hertling, H; Aleksovska, A; Gruschinski, S; Schmorl, S; Kersting, B; Zolnhofer, E M; Sutter, J; Meyer, K; Lönnecke, P; Hey-Hawkins, E

    2016-05-01

    A highly stable metal-organic framework, [{Fe3(ACTBA)2}X·6DEF]n (1; X = monoanion), based on trinuclear iron(iii) secondary building units connected by tetracarboxylates with an anthracene core, 2,6,9,10-tetrakis(p-carboxylatophenyl)anthracene (ACTBA), is reported. Depending on the direction of light polarisation, crystals of 1 exhibit anisotropic optical properties with birefringence Δn = 0.3 (λ = 590 nm). PMID:26906040

  14. Metabolic conversion of dibenz(a,h)anthracene (+/-)trans-1,2-dihydrodiol and chrysene (+/-)trans-3,4-dihydrodiol to vicinal dihydrodiol epoxides

    SciTech Connect

    Chou, M.W.; Fu, P.P.; Yang, S.K.

    1981-07-01

    The hydroxyl groups of dibenz(z,h)anthracene trans-1,2-dihydrodiol and chrysene trans-3,4-dihydrodiol are known to be predominantly in quasi-axial conformations. These dihydrodiols were metabolized by liver microsomes from 3-methylcholanthrene-pretreated rats to form 1,2,3,4-tetrahydrotetrols as the major products. The major metabolites of the dihydrodiols were isolated by reversed-phase high-performance liquid chromatography and identified by ultraviolet-visible absorption and mass spectral analyses. The results indicate that axial hydroxyl groups of dibenz(a,h)anthracene trans-1,2-dihydrodiol and of chrysene trans-3,4-dihydrodiol do not direct metabolism away from their respective vicinal double bond.

  15. Theoretical study of electronically excited radical cations of naphthalene and anthracene as archetypal models for astrophysical observations. Part I. Static aspects.

    PubMed

    Ghanta, S; Reddy, V Sivaranjana; Mahapatra, S

    2011-08-28

    Motivated by the recent discovery of new diffuse interstellar bands and results from laboratory experiments, ab initio quantum chemistry calculations are carried out for the lowest six electronic states of naphthalene and anthracene radical cations. The calculated adiabatic electronic energies are utilized to construct suitable diabatic electronic Hamiltonians in order to perform nuclear dynamics studies in Part II. Complex entanglement of the electronic states is established for both the radical cations and the coupling surfaces among them are also derived in accordance with the symmetry selection rules. Critical examination of the coupling parameters of the Hamiltonian suggests that 29 (out of 48) and 31 (out of 66) vibrational modes are relevant in the nuclear dynamics in the six lowest electronic states of naphthalene and anthracene radical cations, respectively. PMID:21750790

  16. Reduced energy intake and moderate exercise reduce mammary tumor incidence in virgin female BALB/c mice treated with 7,12-dimethylbenz(a)anthracene

    NASA Technical Reports Server (NTRS)

    Lane, Helen W.; Teer, Patricia; Keith, Robert E.; White, Marguerite T.; Strahan, Susan

    1991-01-01

    The concurrent effects of diet (standard AIN-76A, restricted AIN-76A and high-fat diet) and moderate rotating-drum treadmill exercise on the incidence of 7,12-dimethylbenz(a)anthracene-induced mammary carcinomas in virgin female BALB/cMed mice free of murine mammary tumor virus are evaluated. Analyses show that, although energy intake was related to mammary tumor incidence, neither body weight nor dietary fat predicted tumor incidence.

  17. Stereoselective fungal metabolism of 7,12-dimethylbenz(a)anthracene: identification and enantiomeric resolution of a K-region dihydrodiol

    SciTech Connect

    McMillan, D.C.; Fu, P.P.; Cerniglia, C.E.

    1987-10-01

    Syncephalastrum racemosum UT-70 and Cunninghamella elegans ATCC 36112 metabolized 7,12-dimethylbenz(a)anthracene (7,12-DMBA) to hydroxymethyl metabolites as well as 7-hydroxymethyl-12-methylbenz(a)anthracene trans-3,4-, -5,6-, -8,9-, and -10,11-dihydrodiols. The 7,12-DMBA metabolites were isolated by reversed-phase high-performance liquid chromatography and identified by their UV-visible absorption, mass, and nuclear magnetic resonance spectral characteristics. A comparison of the circular dichroism spectra of the K-region (5,6-position) dihydrodiol of both fungal strains with those of the 7,12-DMBA 5S,6S-dihydrodiol formed from 7,12-DMBA by rat liver microsomes indicated that the major enantiomer of the 7-hydroxymethyl-12-methylbenz(a)anthracene trans-5,6-dihydrodiol formed by both fungal strains had a 5R,6R absolute stereochemistry. Direct resolution of the fungal trans-5,6-dihydrodiols by chiral stationary-phase high-performance liquid chromatography indicated that the ratios of the R,R and S,S, enantiomers were 88:12 and 77:23 for S. racemosum and C. elegans, respectively. These results indicate that the fungal metabolism of 7,12-DMBA at the K region (5,6-position) is highly stereoselective and different from that reported for mammalian enzyme systems.

  18. Detection of trace anthracene in soil samples with real-time fluorescence quantitative immuno-PCR using a molecular beacon probe.

    PubMed

    Ye, Qi-Yan; Zhuang, Hui-Sheng; Zhou, Chun

    2009-11-01

    We developed a highly sensitive and robust real-time fluorescence quantitative immuno-PCR (RTFQ-IPCR) method which uses molecular beacon (MB) probe to detect trace anthracene in the environment. This method was performed on serial dilutions of known anthracene concentrations equivalent to 10-fold dilutions of 10fg/mL to 100pg/mL. We obtained a linear relationship between 10fg/mL and 100pg/mL, with y=0.684x+13.221. A correlation coefficient of 0.994 was also identified, with a detection limit of 4.5fg/mL. After investigating the presence of anthracene in soil samples via RTFQ-IPCR, the obtained concentrations were confirmed by ELISA to be correct and believable, with the recovery ratio ranging from 82% to 112.5%. Based on its sensitivity and reproducibility, MB-based RTFQ-IPCR was found to be acceptable for use in on-site field tests to provide rapid, quantitative, and reliable test results for making environmental decisions.

  19. erbB expression changes in ethanol and 7, 12- dimethylbenz (a) anthracene-induced oral carcinogenesis

    PubMed Central

    Jacinto-Alemán, Luis F.; García-Carrancá, Alejandro; Leyba-Huerta, Elba R.; Zenteno-Galindo, Edgar; Jiménez-Farfán, María D.

    2013-01-01

    Objetive: The aim of this study was to determine erbB expression in normal mucosa, oral dysplasia, and invasive carcinomas developed in the hamster’s buccal pouch chemical carcinogenesis model. Study design: Fifty Syrian golden hamsters were equally divided in five groups (A-E); two controls and three experimental group exposed to alcohol, DMBA, or both for 14 weeks. Number of tumors per cheek, volume, histological condition, erbB expression were determined and results were analyzed by the Mann–Whitney U and Dunn’s test. Results: Control groups and those exposed to alcohol (A, B and C respectively) only presented clinical and histological normal mucosa; while those exposed to DMBA or DMBA plus alcohol (D and E groups) developed dysplasia and invasive carcinomas. erbB2, erbB3, and erbB4 increased their expression in alcohol-exposed mucosa, dysplasia, and invasive carcinomas. We observed a similar expression level for erbB2 in dysplasia and carcinomas; while, erbB3 and erbB4 were similar only in carcinomas. Conclusion: The DMBA and alcohol can be considered as carcinogen and promoter for oral carcinogenesis. The erbB expression is different according to their histological condition, suggesting differential participation of the erbB family in oral carcinogenesis induced by alcohol and DMBA. Key words:erbB, 7,12- dimethylbenz(a)anthracene, oral squamous cell carcinoma. PMID:23229248

  20. Anthracene-containing wide-band-gap conjugated polymers for high-open-circuit-voltage polymer solar cells.

    PubMed

    Gong, Xue; Li, Cuihong; Lu, Zhen; Li, Guangwu; Mei, Qiang; Fang, Tao; Bo, Zhishan

    2013-07-25

    The synthesis, characterization, and photophysical and photovoltaic properties of two anthracene-containing wide-band-gap donor and acceptor (D-A) alternating conjugated polymers (P1 and P2) are described. These two polymers absorb in the range of 300-600 nm with a band gap of about 2.12 eV. Polymer solar cells with P1:PC71 BM as the active layer demonstrate a power conversion efficiency (PCE) of 2.23% with a high Voc of 0.96 V, a Jsc of 4.4 mA cm(-2) , and a comparable fill factor (FF) of 0.53 under simulated solar illumination of AM 1.5 G (100 mW cm(-2) ). In addition, P2:PC71 BM blend-based solar cells exhibit a PCE of 1.42% with a comparable Voc of 0.89 V, a Jsc of 3.0 mA cm(-2) , and an FF of 0.53.

  1. Prolactin receptors and androgen-induced regression of 7,12-dimethylbenz(a)anthracene-induced mammary carcinoma.

    PubMed

    Costlow, M E; Buschow, R A; McGuire, W L

    1976-09-01

    Prolactin reverses the inhibitory effects of pharmacological doses of androgen on 7,12-dimethylbenz(a)anthracene-induced mammary tumor growth (Quadri, S.K., Kledzik, G.S., and Meites, J.J. Natl. Cancer Inst., 52: 875-878,1974). To determine whether this effect is due to an alteration in the ability of the tumor cell to bind prolactin, we have quantitated prolactin receptors in androgen-responsive and nonresponsive tumors. Prolactin receptors were measured with 125I-labeled ovine prolactin in a subcellular fraction which reproducibly contained 60 to 80% of the total receptor present in tumor homogenates. Prolactin binding was reversible, reached a steady state in 9 hr, and was completed by excess unlabeled prolactin. Prolactin bound to its receptor with a Kd of approximately 1 X 10(-10) M. Growing tumors were biopsied, and rats bearing regrown tumors were given injections of 4 mg testosterone propionate twice a week. Prolactin receptors were reduced in most of the tumors, which regressed after testosterone treatment by an average of 63% compared to the pretreatment biopsy specimens. Nonresponsive tumors and vehicle-injected controls showed no signifcant alterations in receptor content. This reduction of prolactin receptors is probably insufficient to account for androgen-induced mammary tumor regression. PMID:184948

  2. Soil sterilization affects aging-related sequestration and bioavailability of p,p'-DDE and anthracene to earthworms.

    PubMed

    Slizovskiy, Ilya B; Kelsey, Jason W

    2010-10-01

    Laboratory experiments investigated the effects of soil sterilization and compound aging on the bioaccumulation of spiked p,p'-DDE and anthracene by Eisenia fetida and Lumbricus terrestris. Declines in bioavailability occurred as pollutant residence time in both sterile and non-sterile soils increased from 3 to 203 d. Accumulation was generally higher in sterile soils during initial periods of aging (from 3-103 d). By 203 d, however, bioavailability of the compounds was unaffected by sterilization. Gamma irradiation and autoclaving may have altered bioavailability by inducing changes in the chemistry of soil organic matter (SOM). The results support a dual-mode partitioning sorption model in which the SOM components associated with short-term sorption (the 'soft' or 'rubbery' phases) are more affected than are the components associated with long-term sorption (the 'glassy' or microcrystalline phases). Risk assessments based on data from experiments in which sterile soil was used could overestimate exposure and bioaccumulation of pollutants. PMID:20708831

  3. Polyvinyl pyrrolidone capped fluorescent anthracene nanoparticles for sensing fluorescein sodium in aqueous solution and analytical application for ophthalmic samples.

    PubMed

    Bhopate, Dhanaji P; Mahajan, Prasad G; Garadkar, Kalyanrao M; Kolekar, Govind B; Patil, Shivajirao R

    2015-11-01

    Based on the known complexation ability between polyvinyl pyrrolidone (PVP) and fluorescein sodium (FL Na(+)), fluorescent PVP capped anthracene nanoparticles (PVP-ANPs) were prepared using a reprecipitation method for detection of fluorescein in aqueous solution using the fluorescence resonance energy transfer (FRET) approach. A dynamic light scattering histogram of PVP-ANPs showed narrower particle size distribution and the average particle size was 15 nm. The aggregation-induced enhanced emission (AIEE) of PVP-ANPs was red shifted from its monomer by 1087.22 cm(-1). The maximum emission was seen to occur at 420 nm. The presence of FL Na(+) in the vicinity of PVP-ANPs quenched the fluorescence of PVP-ANPs because of its adsorption on the surface of PVP-ANPs in aqueous suspension. The FL Na(+) and PVP-ANPs were brought close enough, typically to 7.89 nm, which was less than the distance of 10 nm that is required between the energy donor-acceptor molecule for efficient FRET. The quenching results fit into the Stern-Volmer relationship even at temperatures greater than ambient temperatures. The thermodynamic parameters determined from FRET results helped to propose binding mechanisms involving hydrophobic and electrostatic molecular interaction. The fluorescence quenching results were used further to develop an analytical method for estimation of fluorescein sodium from ophthalmic samples available commercially in the market.

  4. Chemopreventive potential of fungal taxol against 7, 12-dimethylbenz[a]anthracene induced mammary gland carcinogenesis in Sprague Dawley rats.

    PubMed

    Gokul Raj, Kathamuthu; Chidambaram, Ranganathan; Varunkumar, Krishnamoorthy; Ravikumar, Vilwanathan; Pandi, Mohan

    2015-11-15

    Breast cancer is the second most prevalent cancer and foremost global public health problem. The present study was designed to appraise the chemopreventive potential of fungal taxol against 7,12-dimethylbenz[a]anthracene (DMBA) induced mammary gland carcinogenesis in Sprague Dawley rats. After 90 days of tumor induction, fungal and authentic taxol were given intraperitoneally once in a week for four weeks. Infrared thermal imaging analysis, serum biochemical parameters such as lipid peroxidase (LPO), creatinine, enzymic and non enzymic antioxidants, liver markers tests such as alanine transaminase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), triglycerides (TG) and lipoproteins was analysed. In addition, histopathological observation (breast, kidney and liver), immunohistochemical analysis (p53 and Her2/neu) and western blotting experiments (bcl-2, bax and caspase-9) were performed both in control and experimental animals. In thermal imaging, decreased temperature was observed in rat treated with fungal and authentic taxol when compared to tumor induced rats. The significant decrease in LPO, creatinine, ALT, AST, TC, TG, lipoproteins and increase in enzymic, non-enzymic antioxidants were exemplified in serum of treated groups. Further histopathology, immunohistochemical and western blot analysis (bax, cas-9 and bcl-2) of apoptotic markers in breast tissues clearly showed the anti-carcinogenic property of fungal taxol. Our findings implement that fungal taxol is a potential chemo preventive agent against DMBA induced mammary gland carcinogenesis.

  5. Effect of anthracene on the interaction between Platymonas helgolandica var. tsingtaoensis and Heterosigma akashiwo in laboratory cultures

    NASA Astrophysics Data System (ADS)

    Bi, Rong; Wang, You; Wang, Renjun; Li, Wei; Tang, Xuexi

    2015-02-01

    Two species of marine phytoplankton, Platymonas helgolandica var. tsingtaoensis and Heterosigma akashiwo, were cultivated in bi-algal cultures to investigate the effect of anthracene (ANT) on the interaction between them. Without ANT, H. akashiwo out-competed P. helgolandica at low initial biomass ratios ( P. helgolandica ( P): H. akashiwo ( H) = 1:4 and 1:1), but not at the highest ( P: H = 4:1). This observation was consistent with the description in Lotka-Volterra two species competition model. It was found that P. helgolandica was excluded at low initial biomass ratios, while the unstable equilibrium between two species was predicted at the highest. For both species, carrying capacity and maximal specific growth rate decreased in bi-algal cultures compared to those in monocultures. H. akashiwo exhibited a higher sensitivity to ANT than P. helgolandica. This resulted markedly in a reduced cell density of H. akashiwo but an increased cell density of P. helgolandica. Carrying capacity of P. helgolandica was consistently higher in bi-algal cultures with ANT than those without ANT, suggesting that ANT, through the elimination of H. akashiwo, generated the dominance of P. helgolandica independently of initial biomass ratios. This study showed a density-dependent effect of harmful alga ( H. akashiwo) on dietary alga ( P. helgolandica), and indicated that ocean pollutant ANT could induce the succession of marine phytoplankton.

  6. Understanding the ring current effects on magnetic shielding of hydrogen and carbon nuclei in naphthalene and anthracene.

    PubMed

    Cuesta, Inmaculada Garíca; De Merás, Alfredo Sánchez; Pelloni, Stefano; Lazzeretti, Paolo

    2009-03-01

    The local response to an external magnetic field normal to the molecular plane of naphthalene and anthracene was investigated via current density and magnetic shielding density maps. The Biot-Savart law shows that the deshielding caused by pi-ring currents in naphthalene is stronger for alpha- than for beta-protons due to geometrical factors. The shielding tensor of the carbon nuclei in both molecules is strongly anisotropic and its out-of-plane component determines the up-field chemical shift of (13)C in nuclear magnetic resonance spectra. The pi-ring currents flowing beyond the C-skeleton in front of a probe carbon nucleus, and on remote parts of the molecular perimeter, yield positive contributions to the out-of-plane component of carbon shielding as big as approximately 10-15% of the total values. Near Hartree-Fock estimates of magnetizability and magnetic shielding at the nuclei fully consistent with the current model are reported. PMID:18711723

  7. Initiation of cell proliferation in livers of the viviparous fish Poeciliopsis lucida with 7,12-dimethylbenz(a)anthracene

    SciTech Connect

    Schultz, M.E.; Kaplan, L.A.E.; Schultz, R.J. )

    1989-04-01

    Stimulation of liver cell proliferation by sublethal exposures to 7,12-dimethylbenz(a)anthracene (DMBA) is examined in the small, viviparous fish Poeciliopsis lucida. Poeciliopsis is susceptible to induction of liver tumors by repeated short-term exposures, under 24 hr, to waterborne DMBA at 5 ppm. Exposures to 5 ppm for 24 hr was lethal to fish under 1 month old and resulted in 60% mortality of adult females 20-25 mm in length. Response to 16-, 20-, and 22-hr exposures of 5 ppm DMBA, as measured by mitotic index, was similar in females of two size classes, 20-25 mm and 26-30 mm. Differences were observed in the onset of mitosis in livers of fish exposed for 16 hr vs 20 or 22 hr. Hepatocyte proliferation did not begin until 10-11 days after the 16-hr exposure and lasted for only 3 days. When exposure was increased to 20 or 22 hr, mitotic activity was observed earlier, 2 days following treatment, and continued for 6-8 days. The peak period of cell proliferation also varied, occurring 12 days after a 16-hr exposure, 4 days after a 20-hr exposure, and at least 10 days after a 22-hr exposure. The mitotic index was the highest on the final day specimens of the 22-hr treatment were collected. These results suggest that the toxic properties of DMBA in stimulating cell proliferation may function as an important cofactor in hepatocarcinogenesis.

  8. CO-induction of rat intestinal cancers with 7,12-dimethylbenz(a)anthracene and medroxyprogesterone acetate

    SciTech Connect

    Hass, G.; Galt, R.; Coogan, P.; Friese, J.

    1986-03-01

    Medroxy progesterone acetate (P) is a progestin used for treatment of sex hormone-dependent human cancers. In a study of its action, 7,12-dimethyl-benz(a)anthracene (DMBA) was given, i.g., to 50-52 day old intact or gonadectomized Sprague-Dawley rats of both sexes. Groups were given 0, 5, 25 or 100 mg of P +/- 2, .5, .1, .01 or .001 mg of 17 beta estradiol (E2), s.c., each week for 12-36 weeks. Those given P often developed, independent of sex or gonadectomy, multiple intestinal adenomas and carcinomas, especially in the jejunum. At doses of P tumor incidence was as follows: 0 mg, 2/63; 5 mg, 18/96; 25 mg, 35/57; 100 mg, 72/155. Combinations of P with doses of E2 at 2, .5 or .1 mg reduced tumor incidence 65%. At 25 or 100 mg doses of P, DMBA induction of mammary tumors was inhibited, while atrophy of ovaries and adrenal cortex was impressive. Hence, this is the only progestin, which favors DMBA induction of tumors of the rat intestine, while extinguishing mammary tumors. This matter may bear on presence of hormone receptors in human colo-rectal cancers.

  9. Protection Against Dimethylbenz[a] Anthracene-Induced Breast Cancer in Female Rats by α-Lactalbumin

    PubMed Central

    Roy, Somdutta Sinha; Mukherjee, Shyamali; Ballard, Billy R; Das, Salil K

    2016-01-01

    Consumption of α-lactalbumin as dietary protein offers a beneficial effect on breast cancer development. Breast cancer was developed by gavage administration of single dose of dimethylbenz(a)anthracene (DMBA) in female rats, maintained on AIN-76A diet with either 20% casein or α-lactalbumin (a component of whey protein). All tumors were detected by palpation. After approximately 130 days of DMBA administration, the animals were euthanized. There was a delay in the development of breast tumor in the α-lactalbumin group in comparison to the casein group. The number of tumors per rat was less in the α-lactalbumin group than that in the casein group at any time point up to 130 days after DMBA administration. Also the incidence of tumors and tumor volume was less in the α-lactalbumin group than those in the casein group. The casein group had a mixture of grade I, grade II and grade III tumors whereas the α-lactalbumin group had mostly grade I tumor. Furthermore, the proliferative index was significantly lower in the α-lactalbumin group than that in the casein group. PMID:27517093

  10. Levels of benzo[a]pyrene and benzo[a]anthracene in smoked "Provola" cheese from Calabria (Italy).

    PubMed

    Naccari, Clara; Cristani, Mariateresa; Licata, Patrizia; Giofrè, Francesco; Trombetta, Domenico

    2008-01-01

    Levels of benzo[a]pyrene (BaP) and benzo[a]anthracene (BaA) in "Provola" cheese samples from Calabria, smoked naturally and using commercial smoke-flavouring, have been determined. A comparative study of BaP and BaA concentrations was carried out on rind, exterior zone, core and slice of these samples. Quantitative determination of BaP and BaA was ascertained by HPLC using fluorescence detection. Levels of BaP and BaA were found in all smoked "Provola" cheese samples, but higher in cheese smoked with natural methods (0.46-1.13 µg kg⁻¹ for BaP and 1.38-9.29 µg kg⁻¹ for BaA) compared to samples smoked using commercial flavouring (0.085-0.32 µg kg⁻¹ for BaP and 1.20-2.98 µg kg⁻¹ for BaA). The smoking process contributes to polycyclic aromatic hydrocarbons contamination; however, for improved food safety, the use of commercial buffered smoke is preferable to traditional smoking procedures.

  11. Unexpected formation of π-expanded isoquinoline from anthracene possessing four electron-donating groups via the Duff reaction.

    PubMed

    Węcławski, Marek K; Deperasińska, Irena; Leniak, Arkadiusz; Banasiewicz, Marzena; Kozankiewicz, Bolesław; Gryko, Daniel T

    2016-08-01

    New synthetic methods leading towards π-expanded heterocycles are sought after mainly due to their promising opto-electronic properties. Subjecting 1,5,9,10-tetramethoxyanthracene to the modern Duff reaction conditions led to the formation of a compound possessing the 2-azabenzoanthrone (dibenzo[de,h]isoquinolin-7-on) skeleton instead of the expected dialdehyde. This non-typical course of reaction can be rationalized by the double electrophilic aromatic substitution at two neighboring electron-rich positions of anthracene followed by oxidation of the resulting intermediate to form a pyridine ring. Optical studies supported by the quantum chemistry calculations indicated the lack of excited-state intramolecular proton transfer (ESIPT); for energy reasons, only one tautomeric form, with a hydrogen atom bonded to one of the two nearby oxygen atoms, was populated in the electronic ground S0 and in the excited S1 states. Nonradiative depopulation of the S1 state proceeded via internal conversion stimulated by the presence of the low frequency vibrational modes. Our serendipitous discovery represents the most complex case of rearrangement of aromatic compounds under Duff reaction conditions and could help to design analogous processes. At the same time this is the simplest method for the synthesis of derivatives of 2-azabenzoanthrone. PMID:27367169

  12. Incorporation of anthracene into zeolites: confinement effect on the recombination rate of photoinduced radical cation-electron pair.

    PubMed

    Marquis, Séverine; Moissette, Alain; Brémard, Claude

    2006-07-17

    FT-Raman spectrometry in combination with diffuse reflectance UV/Vis absorption (DRUVv) and fluorescence emission indicate that complete anthracene (ANT) sorption as intact molecules takes place over 6 months in the medium pores of non-Brønsted acidic M(n)ZSM-5 zeolites (n=0.0, 3.4, 6.6; M=Na+, K+, Rb+, Cs+) with 1 ANT per unit cell loading. The combined effect of confinement and electrostatic field induced by bulky cations (Rb+, Cs+) leads to specific changes in the occluded ANT Raman spectra after very long organization periods (one year). The laser photolysis (266 nm, 355 nm) of ANT@M(n)ZSM-5 equilibrated samples generates long-lived charge separated species in aluminum rich zeolites (n=3.4, 6.6). The very long-lived radical pairs are characterized by conventional DRUVv and CW-EPR spectroscopy. The direct charge recombination rates of ANT.+-electron pairs are dispersive, extending over a broad range of timescales. The kinetic constant values are found to increase dramatically with the aluminum content and increase markedly with M+ according to the following order Na+ < K+ < Rb+ < Cs+. The small reorganization energy (lambda) of ZSM-5 zeolite pores coupled with large negative free energy changes (-DeltaG degrees ) between the ground state ANT oxidation potential and Fermi level of aluminum rich M(n)ZSM-5 explain the observed trends of the ANT.+@M(n)ZSM-5.- charge recombination rates.

  13. Long-lived radical cation-electron pairs generated by anthracene sorption in non Brønsted acidic zeolites.

    PubMed

    Marquis, Séverine; Moissette, Alain; Vezin, Hervé; Brémard, Claude

    2005-03-10

    The sorption of anthracene (ANT) in non Brønsted acidic ZSM-5 zeolite through the mere exposure at room temperature of solid ANT and dehydrated zeolite crystals with Li(3.4)(AlO2)n(SiO2)(96-n) chemical formulas per unit cell generates spontaneous ionization of ANT (IP 7.44 eV in the gas phase). In contrast, ANT was found to be sorbed as an intact molecule in M(3.4)ZSM-5 with M = Na+, K+, Rb+, and Cs+. The radical cation (ANT*+) of the long-lived ANT*+@Li(3.4)ZSM-5*- pair was characterized by conventional diffuse reflectance UV-visible and resonance Raman spectrometry. In contrast, the X-band continuous wave (CW) EPR signal was found to be typical of a weakly coupled spin correlated ion pair. The two-dimension hyperfine sublevel correlation (2D-HYSCORE) spectra provide a detailed description of the microenvironment of the trapped electron of the ANT*+@Li(n)ZSM-5*- pair. The trapped electron appears localized in close proximity of occluded ANT*+, Li+, and the Si-O-Al nearest group of the zeolite framework.

  14. Microemulsions of N-alkylimidazolium ionic liquid and their performance as microreactors for the photocycloaddition of 9-substituted anthracenes.

    PubMed

    Li, Xin-Wei; Zhang, Jin; Zheng, Li-Qiang; Chen, Bin; Wu, Li-Zhu; Lv, Feng-Feng; Dong, Bin; Tung, Chen-Ho

    2009-05-19

    The phase behavior of the ternary system consisting of an ionic liquid (1-tetradecyl-3-methylimidazolium bromide [C14mim]Br), p-xylene, and water were investigated. Depending on the composition of the ternary system, formation of hexagonal and lamellar liquid crystals as well as microemulsions was observed. 1H NMR spectroscopy study, 2D ROESY spectroscopic analysis, and rheological measurements of the microemulsions indicated that p-xylene is preferably located in the hydrophobic core and the palisade shells of the microemulsions. The sizes of the microemulsion droplets for the samples with water/[C14mim]Br ratio of 78:22 are measured by both dynamic light scattering (DLS) and transmission electron microscopy with the freeze-fracture technique (FF-TEM). Upon change of the mole ratio of the solubilized xylene to [C14mim]Br from 0 to 2.4, the diameters of the microemulsion droplets increase from ca. 20 to 90 nm and size distribution gets broad. These microemulsions can solubilize and preorientate anthracene derivatives with a polar 9-substituent, and thus may enhance the head-to-head cyclomers in the photocyclization of these substrates. PMID:19432490

  15. Using acetone as solvent to study removal of anthracene in soil inhibits microbial activity and alters nitrogen dynamics.

    PubMed

    Núñez, Edgar Vázquez; Rodríguez, Viviana; Gaytán, Alejandro García; Luna-Guido, Marco; Betancur-Galvis, Liliana A; Marsch, Rodolfo; Dendooven, Luc

    2009-08-01

    Acetone is often used as a carrier to contaminate soil with polycyclic aromatic hydrocarbons (PAHs) and then to study the factors that control their removal. Acetone is an organic solvent that might affect soil processes. An alkaline saline (Texcoco soil) and an agricultural soil (Acolman soil) were amended with or without acetone, nitrogen + phosphorus (NP), and contaminated with anthracene at 520 mg/kg soil while emissions of CO2 and N2O and concentrations of NH4+, NO2(-) and NO3(-) were monitored. The CO2 emission rate decreased greater than 10 times in the soils amended with acetone. Emission of N2O decreased 70 times in the Acolman soil amended with acetone and NP and 5 times in the Texcoco soil. The concentration of NH4+ decreased in the unamended Acolman and Texcoco soil but increased when acetone was added in the first and remained constant in the latter. Acetone inhibited the increase in the amount of NO3(-) in the Acolman soil but not in the Texcoco soil. It was found that microbial activity as evidenced by the emission of CO2, nitrification, and production of N2O were inhibited by acetone. The amount of acetone used as solvent should thus be kept to a minimum, but it can be assumed that its effect on soil processes will be temporary, as microorganisms are known to repopulate soil quickly.

  16. A quantum chemistry study of the van der Waals dimers of benzene, naphthalene, and anthracene: Crossed (D{sub 2d}) and parallel-displaced (C{sub 2h}) dimers of very similar energies in the linear polyacenes

    SciTech Connect

    Gonzalez, C.; Lim, E.C.

    2000-04-06

    A quantum chemistry study of the ground-state structures and binding energies of the van der Waals dimers of benzene, naphthalene, and anthracene has been made at the MP2/6-31G and MP2/6-31+G levels of theory. For naphthalene and anthracene, the calculations yield two low energy dimers of very similar energies: D{sub 2d} (crossed) and C{sub 2h} (parallel-displaced). Conformers, analogous to the T-shaped dimer of benzene, are less stable than the crossed and the parallel-displaced dimers. BSSE-corrected MP2/6-31+G/MP2/6-31G binding energies of the crossed and the parallel-displaced dimers are, respectively, 15.77 and 15.65 kJ/mol for naphthalene and 36.40 and 31.84 kJ/mol for anthracene. The fully optimized MP2/6-31G structures of the parallel-displaced dimer of naphthalene has a horizontal displacement of 1.5 {angstrom} along the short axes of the monomers and a vertical displacement of 3.5 {angstrom}. The corresponding horizontal and vertical separations for the parallel-displaced (PD) dimer of anthracene are 1.1 and 3.6 {angstrom}, respectively. for the crossed dimers, the vertical separation of the aromatic rings is 3.6 {angstrom} for naphthalene and 3.3 {angstrom} for anthracene. The greater binding energy and the shorter horizontal displacement of the anthracene PD dimer relative to the naphthalene PD dimer are consistent with the stronger dispersion interactions expected of a larger dimer. The greater stability and smaller vertical separation of the crossed dimer of anthracene relative to that of naphthalene can also be attributed to the disparity in the dispersion interactions.

  17. Chemopreventive efficacy of naringenin-loaded nanoparticles in 7,12-dimethylbenz(a)anthracene induced experimental oral carcinogenesis.

    PubMed

    Sulfikkarali, Nechikkad; Krishnakumar, Narendran; Manoharan, Shanmugam; Nirmal, Ramadas Madhavan

    2013-04-01

    Nanochemoprevention has been introduced recently as a novel approach for improving phytochemicals bioavailability and anti-tumor effect. The present study is designed to evaluate the chemopreventive efficacy of prepared naringenin-loaded nanoparticles (NARNPs) relative to efficacy of free naringenin (NAR) against 7,12-dimethyl benz(a)anthracene (DMBA)-induced oral carcinogenesis by evaluating the status of lipid peroxidation, antioxidants and immunoexpression patterns of proliferating cell nuclear antigen (PCNA) and p53 proteins. Transmission electron microscope (TEM) and dynamic light scattering (DLS) investigations have confirmed a narrow size distribution of the prepared nanoparticles (40-90 nm) with ~88 % encapsulation efficiency. Oral squamous cell carcinoma (OSCC) was developed in the buccal pouch of golden Syrian hamsters by painting with 0.5 % DMBA in liquid paraffin three times a week for 14 weeks. DMBA painted animals revealed the morphological changes, hyperplasia, dysplasia and well-differentiated squamous cell carcinoma. Moreover, the status of lipid peroxidation, antioxidants and immunoexpression of PCNA and p53 were significantly altered during DMBA-induced oral carcinogenesis. Oral administration of NARNPs (50 mg NAR/kg body weight/day) to DMBA-treated animals completely prevented the tumor formation as compared to the free NAR and significantly reduced the degree of histological lesions, in addition to restoration of the status of biochemical and molecular markers during oral carcinogenesis. In addition, NARNPs have more potent anti-lipid peroxidative, antiproliferative effect and antioxidant potentials compared to free NAR in DMBA-induced oral carcinogenesis. In conclusion, the present study suggests that NARNPs could be a potentially useful drug carrier system for targeted delivery of naringenin for cancer chemoprevention. PMID:23233294

  18. Estrogenic status modulates the effect of soy on hepatic responses to 7,12-dimethylbenz(a)anthracene (DMBA)

    SciTech Connect

    Singhal, Rohit; Badger, Thomas M.; Ronis, Martin J.

    2009-01-01

    We examined the influence of estradiol (E2) status and soy protein isolate (SPI) intake on the hepatic responses altered by 7,12-dimethylbenz(a)anthracene (DMBA, a polycyclic aromatic hydrocarbon [PAH]). Sprague-Dawley rats were ovariectomized (OVX) at PND50 and infused with E2 or vehicle for 14 d and gavaged with 50 mg/kg DMBA or vehicle 24 h before sacrifice at PND64. Rats were fed an AIN-93G diet made with SPI or casein as sole protein source throughout the study. Basal AhR protein levels were reduced (P < 0.05) by SPI feeding irrespective of the E2 status. However, DMBA increased (P < 0.05) AhR-induced CYP1A1 gene expression in OVX, SPI-fed rats, but reduced (P < 0.05) CYP1A1 in OVX + E2, SPI-fed rats. Chromatin-immunoprecipitation demonstrated lower (P < 0.05) DMBA-mediated recruitment of estrogen receptor alpha to the CYP1A1 promoter by SPI feeding in the presence of E2, suggesting an estrogen-like action of SPI on DMBA-mediated signaling in the absence of E2. Further, microarray analysis (Rat 230-2.0 Affymetrix-GeneChip{sup TM}) revealed 231 genes common to SPI + DMBA and SPI + E2 + DMBA (normalized to E2) treatments. AhR-activated genes (CYP1A1, CYP1A2, and NQO1) were down-regulated by SPI + E2 + DMBA compared to SPI + DMBA. Unique interactions among SPI, DMBA and E2 altered the expression profile of 316 genes, not observed by either treatment alone. Our data suggest that although E2 status does not effect soy-mediated AhR degradation, it modulates the effects of soy on many genes, including CYP1A1.

  19. Enhanced susceptibility of ovaries from obese mice to 7,12-dimethylbenz[a]anthracene-induced DNA damage

    PubMed Central

    Ganesan, Shanthi; Nteeba, Jackson; Keating, Aileen F.

    2014-01-01

    7,12-dimethylbenz[a]anthracene (DMBA) depletes ovarian follicles and induces DNA damage in extra-ovarian tissues, thus, we investigated ovarian DMBA-induced DNA damage. Additionally, since obesity is associated with increased offspring birth defect incidence, we hypothesized that a DMBA-induced DNA damage response (DDR) is compromised in ovaries from obese females. Wild type (lean) non agouti (a/a) and KK.Cg-Ay/J heterozygote (obese) mice were dosed with sesame oil or DMBA (1mg/kg; intraperitoneal injection) at 18 wks of age, for 14 days. Total ovarian RNA and protein were isolated and abundance of Ataxia telangiectasia mutated (Atm), X-ray repair complementing defective repair in chinese hamster cells 6 (Xrcc6), Breast cancer type 1 (Brca1), Rad 51 homolog (Rad51), Poly [ADP-ribose] polymerase 1 (Parp1) and Protein kinase, DNA-activated, catalytic polypeptide (Prkdc) were quantified by RT-PCR or Western blot. Phosphorylated histone H2AX (γH2AX) level was determined by Western blotting. Obesity decreased (P < 0.05) basal protein abundance of PRKDC and BRCA1 proteins but increased (P < 0.05) γH2AX and PARP1 proteins. Ovarian ATM, XRCC6, PRKDC, RAD51 and PARP1 proteins were increased (P < 0.05) by DMBA exposure in lean mice. A blunted DMBA-induced increase (P < 0.05) in XRCC6, PRKDC, RAD51 and BRCA1 was observed in ovaries from obese mice, relative to lean counterparts. Taken together, DMBA exposure induced γH2AX as well as the ovarian DDR, supporting that DMBA causes ovarian DNA damage. Additionally, ovarian DDR was partially attenuated in obese females raising concern that obesity may be an additive factor during chemical-induced ovotoxicity. PMID:25448685

  20. Effects of selenium on 7,12-dimethylbenz(a)anthracene-induced mammary carcinogenesis and DNA adduct formation

    SciTech Connect

    Ip, C.; Daniel, F.B.

    1985-01-01

    The purpose of the present investigation was to determine the effects of dietary selenium deficiency or excess on 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary neoplasia in rats and to delineate whether selenium-mediated modification of mammary carcinogenesis was associated with changes in carcinogen:DNA adduct formation and activities of liver microsomal enzymes that are involved in xenobiotic metabolism. Female Sprague-Dawley rats were divided into three groups from weaning and were maintained on one of three synthetic diets designated as follows: selenium deficient (less than 0.02 ppm); selenium adequate (0.2 ppm); or selenium excess (2.5 ppm). For the DMBA binding and DNA adduct studies, rats were given a dose of (/sup 3/H)DMBA p.o. after 1 month on their respective diets. Results from the liver and the mammary gland indicated that neither selenium deficiency nor excess had any significant effect on the binding levels, which were calculated on the basis of total radioactivity isolated with the purified DNA. Furthermore, it was found that dietary selenium intake did not seem to affect quantitatively or qualitatively the formation of DMBA:DNA adducts in the liver. Similarly, in a parallel group of rats that did not receive DMBA, the activities of aniline hydroxylase, aminopyrine N-demethylase, and cytochrome c reductase were not significantly altered by dietary selenium levels. Concurrent with the above experiments, the effect of dietary selenium intake on carcinogenesis was also monitored. Results of this experiment indicated that selenium deficiency enhanced mammary carcinogenesis only when this nutritional condition was maintained in the postinitiation phase. Likewise, an excess of selenium intake inhibited neoplastic development only when this regimen was continued after DMBA administration.

  1. Hepatic metabolism of 7,12-dimethylbenz(a)anthracene in male, female, and ovariectomized Sprague-Dawley rats

    SciTech Connect

    Vater, S.T.; Baldwin, D.M.; Warshawsky, D. )

    1991-01-15

    Dimethylbenz(a)anthracene (DMBA) is a potent inducer of mammary tumors in intact female Sprague-Dawley rats, but not in males or ovariectomized females (OVX). Qualitative and quantitative aspects of hepatic metabolism of DMBA were examined in these three groups of rats, using the nonrecirculating perfused liver, to determine whether the production of proximate carcinogenic metabolites of DMBA by the liver differed among these groups in the same manner as does sensitivity to tumor induction. DMBA was infused into the liver at a constant rate for 60 min. Rates of appearance of DMBA and its metabolites were measured in perfusate and bile during the infusion period and the first 60 min thereafter. The maximum rate of appearance of total metabolites in the perfusate, seen at the end of the infusion period, was highest in the intact female (2.6 +/- 0.3 nmol/(g x min)), slightly lower in the OVX (2.3 +/- 0.2 nmol/(g x min)) and significantly lower in the male (1.0 +/- 0.1 nmol/(g x min)). The rates of appearance of metabolites in the bile showed the same order as those seen in the perfusate. The major metabolites extracted from the perfusate in all three groups were dihydrodiols, hydroxymethyl metabolites, and several unidentified metabolites. The 3,4-dihydrodiol, a proximate carcinogenic metabolite, appeared in the perfusate at higher rates in the intact female and OVX than in the male. Hydrolysis of bile samples showed that glucuronidation was a major pathway in the excretion of DMBA metabolites in bile. High performance liquid chromatographic analysis indicated that hydrolysis of DMBA glucuronides yielded the 7- and 12-hydroxymethyl metabolites and an unidentified metabolite designated X. The major hydrolysis product in the male was 12-hydroxymethyl while X was found to be the major product in the intact female and OVX.

  2. Adduct formation of 7,12-dimethylbenz(a)anthracene in the embryo of the Japanese medaka (Oryzias latipes)

    SciTech Connect

    Liu, H.; Cooper, K.R.

    1995-12-31

    DNA adduct formation of 7,1 2-dimethylbenz(a)anthracene (DMBA) in vivo in the Japanese medaka embryo were investigated using {sup 32}P-postlabeling analysis. 1-compounds (endogenous adducts) were not observed in the Japanese medaka embryo on days 4 (prior to liver formation), 6 (liver/swim bladder) or 10 (prior to hatch) of development. The level of DMBA:DNA adducts were concentration-dependent over the range of 0.625 ppm (Total Adducts 0.05707 pmol/mg of DNA) to 2.50 ppm (0.43341 pmol/mg of DNA) and decreased at 5.00 ppm (0.25338 pmol/mg of DNA) after medaka embryos were exposed to DMBA for 6 days from the day of fertilization. The decrease in DMBA:DNA adducts at 5.00 ppm was probably due to embryo toxicity (78% death). The level of DMBA:DNA adducts formed from the embryos exposed to DMBA for 24 hr decreased as the stage of development increased: day 4 > day 6 > day 10; 0.0262, 0.0179, 0.0129 pmol/mg of DNA, respectively. The level of DMBA:DNA adducts increased as the length of exposure increased: 4 day < 6 day < 10 day; 0.0233, 0.0614, 0.1502, respectively. There was both a time and dose dependence to the number of adducts detected. The data presented demonstrated the development of DM BA-DNA adducts in the developing Japanese medaka (Oryzias latipes) and the lack of I-compounds.

  3. Enhanced susceptibility of ovaries from obese mice to 7,12-dimethylbenz[a]anthracene-induced DNA damage

    SciTech Connect

    Ganesan, Shanthi Nteeba, Jackson Keating, Aileen F.

    2014-12-01

    7,12-Dimethylbenz[a]anthracene (DMBA) depletes ovarian follicles and induces DNA damage in extra-ovarian tissues, thus, we investigated ovarian DMBA-induced DNA damage. Additionally, since obesity is associated with increased offspring birth defect incidence, we hypothesized that a DMBA-induced DNA damage response (DDR) is compromised in ovaries from obese females. Wild type (lean) non agouti (a/a) and KK.Cg-Ay/J heterozygote (obese) mice were dosed with sesame oil or DMBA (1 mg/kg; intraperitoneal injection) at 18 weeks of age, for 14 days. Total ovarian RNA and protein were isolated and abundance of Ataxia telangiectasia mutated (Atm), X-ray repair complementing defective repair in Chinese hamster cells 6 (Xrcc6), breast cancer type 1 (Brca1), Rad 51 homolog (Rad51), poly [ADP-ribose] polymerase 1 (Parp1) and protein kinase, DNA-activated, catalytic polypeptide (Prkdc) were quantified by RT-PCR or Western blot. Phosphorylated histone H2AX (γH2AX) level was determined by Western blotting. Obesity decreased (P < 0.05) basal protein abundance of PRKDC and BRCA1 proteins but increased (P < 0.05) γH2AX and PARP1 proteins. Ovarian ATM, XRCC6, PRKDC, RAD51 and PARP1 proteins were increased (P < 0.05) by DMBA exposure in lean mice. A blunted DMBA-induced increase (P < 0.05) in XRCC6, PRKDC, RAD51 and BRCA1 was observed in ovaries from obese mice, relative to lean counterparts. Taken together, DMBA exposure induced γH2AX as well as the ovarian DDR, supporting that DMBA causes ovarian DNA damage. Additionally, ovarian DDR was partially attenuated in obese females raising concern that obesity may be an additive factor during chemical-induced ovotoxicity. - Highlights: • DMBA induces markers of ovarian DNA damage. • Obesity induces low level ovarian DNA damage. • DMBA-induced DNA repair response is altered by obesity.

  4. Inhibition of 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis by S-allylcysteine.

    PubMed

    Balasenthil, S; Nagini, S

    2000-07-01

    Consumption of garlic has been reported to be associated with decreased risk of cancer. We used the 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch carcinoma model to assess the oral chemopreventive potential of S-allylcysteine (SAC), a water-soluble constituent of garlic. Hamsters were divided into four groups of six animals each. The right buccal pouches of the animals in group I were painted with a 0.5% solution of DMBA in liquid paraffin three times a week. The animals in group II were painted with DMBA as in group I and in addition received 200 mg/kg body weight SAC intragastrically three times a week on days alternate to DMBA application. Group III animals received SAC as in group II. Animals in group IV received neither DMBA nor SAC and served as control. The hamsters were killed after an experimental period of 14 weeks. Biochemical measurements were carried out on tumour and normal pouch tissues. Measurement of lipid peroxidation, reduced glutathione (GSH), glutathione peroxidase (GPx) and glutathione S-transferase (GST) was used to monitor the chemopreventive potential of SAC. All hamsters painted with DMBA alone for 14 weeks developed well-differentiated squamous cell carcinomas. Diminished lipid peroxidation in the oral tumour tissue was accompanied by a significant increase in the levels of GSH, GPx and GST. Administration of SAC significantly suppressed DMBA-induced oral carcinogenesis as revealed by the absence of neoplasms. The results of the present study suggest that garlic may exert its chemopreventive effects by modulating lipid peroxidation and enhancing the levels of GSH, GPx and GST. PMID:10899678

  5. S-allylcysteine, a garlic constituent, inhibits 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis.

    PubMed

    Balasenthil, S; Ramachandran, C R; Nagini, S

    2001-01-01

    The effect of S-allylcysteine (SAC), a water-soluble garlic constituent, on 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis was investigated in male Syrian hamstes. Forty hamsters were divided into 4 groups of 10 animals. The right buccal pouches of the animals in Group I were painted with a 0.5% solution of DMBA in liquid paraffin three times a week. The animals in Group II were painted with DMBA as in Group I and, in addition, received 200 mg/kg body wt p.o. SAC three times a week on days alternate to DMBA application. Group III animals received SAC as in Group II. Group IV animals received neither DMBA nor SAC and served as the control. The hamsters were killed after an experimental period of 14 wk. Measurement of lipid peroxidation, the antioxidant enzymes superoxide dismutase (SOD) and catalase, in the buccal pouch mucosa, liver, and circulation was used to monitor the chemopreventive potential of SAC. All hamsters painted with DMBA alone developed tumors identified histologically as well-differentiated squamous cell carcinomas. In hamsters bearing DMBA-induced buccal pouch tumors, diminished lipid peroxidation in the tumor tissue was accompanied by decreased activities of SOD and catalase, whereas in the liver and circulation, enhanced lipid peroxidation was associated with compromised antioxidant defenses. Administration of SAC suppressed the incidence of DMBA-induced HBP tumors as revealed by the absence of carcinomas. Histologically, only keratosis was observed. SAC modulated DMBA-induced decreased susceptibility of the HBP to lipid peroxidation while simultaneously enhancing SOD and catalase activities, whereas in the liver and circulation, SAC decreased the extent of lipid peroxidation and significantly enhanced antioxidant activities. We suggest that SAC exerts its chemopreventive effects by modulating lipid peroxidation and enhancing antioxidant activities in the target organ as well as in the liver and

  6. Caribbean yellow band disease compromises the activity of catalase and glutathione S-transferase in the reef-building coral Orbicella faveolata exposed to anthracene.

    PubMed

    Montilla, Luis Miguel; Ramos, Ruth; García, Elia; Cróquer, Aldo

    2016-05-01

    Healthy and diseased corals are threatened by different anthropogenic sources, such as pollution, a problem expected to become more severe in the near future. Despite the fact that coastal pollution and coral diseases might represent a serious threat to coral reef health, there is a paucity of controlled experiments showing whether the response of diseased and healthy corals to xenobiotics differs. In this study, we exposed healthy and Caribbean yellow band disease (CYBD)-affected Orbicella faveolata colonies to 3 sublethal concentrations of anthracene to test if enzymatic responses to this hydrocarbon were compromised in CYBD-affected tissues. For this, a 2-factorial fully orthogonal design was used in a controlled laboratory bioassay, using tissue condition (2 levels: apparently healthy and diseased) and pollutant concentration (4 levels: experimental control, 10, 30 and 100 ppb concentration) as fixed factors. A permutation-based ANOVA (PERMANOVA) was used to test the effects of condition and concentration on the specific activity of 3 enzymatic biomarkers: catalase, glutathione S-transferase, and glutathione peroxidase. We found a significant interaction between the concentration of anthracene and the colony condition for catalase (Pseudo-F = 3.84, df = 3, p < 0.05) and glutathione S-transferase (Pseudo-F = 3.29, df = 3, p < 0.05). Moreover, our results indicated that the enzymatic response to anthracene in CYBD-affected tissues was compromised, as the activity of these enzymes decreased 3- to 4-fold compared to healthy tissues. These results suggest that under a potential scenario of increasing hydrocarbon coastal pollution, colonies of O. faveolata affected with CYBD might become more vulnerable to the deleterious effects of chemical pollution.

  7. Quantitative structure-activity relationships for chronic toxicity of alkyl-chrysenes and alkyl-benz[a]anthracenes to Japanese medaka embryos (Oryzias latipes).

    PubMed

    Lin, Hongkang; Morandi, Garrett D; Brown, R Stephen; Snieckus, Victor; Rantanen, Toni; Jørgensen, Kåre B; Hodson, Peter V

    2015-02-01

    Alkylated polycyclic aromatic hydrocarbons (alkyl-PAHs) are a class of compounds found at significant concentrations in crude oils, and likely the main constituents responsible for the chronic toxicity of oil to fish. Alkyl substituents at different locations on the aromatic rings change the size and shape of PAH molecules, which results in different interactions with tissue receptors and different severities of toxicity. The present study is the first to report the toxicity of several alkylated derivatives of chrysene and benz[a]anthracene to the embryos of Japanese medaka (Oryzias latipes) using the partition controlled delivery (PCD) method of exposure. The PCD method maintained the desired exposure concentrations by equilibrium partitioning of hydrophobic test compounds from polydimethylsiloxane (PDMS) films. Test concentrations declined by only 13% over a period of 17 days. Based on the prevalence of signs of blue sac disease (BSD), as expressed by median effective concentrations (EC50s), benz[a]anthracene (B[a]A) was more toxic than chrysene. Alkylation generally increased toxicity, except at position 2 of B[a]A. Alkyl-PAHs substituted in the middle region had a lower EC50 than those substituted at the distal region. Except for B[a]A and 7-methylbenz[a]anthracene (7-MB), estimated EC50 values were higher than their solubility limits, which resulted in limited toxicity within the range of test concentrations. The regression between log EC50s and logKow values provided a rough estimation of structure-activity relationships for alkyl-PAHs, but Kow alone did not provide a complete explanation of the chronic toxicity of alkyl PAHs.

  8. Crystal structure of [(1,2,3,4,11,12-η)-anthracene]tris­(tri­methyl­stann­yl)cobalt(III)

    PubMed Central

    Brennessel, William W.; Ellis, John E.

    2014-01-01

    The asymmetric unit of the title structure, [Co(η6-C14H10){Sn(CH3)3}3], contains two independent mol­ecules. Each anthracene ligand is η6-coordinating to a CoIII cation and is nearly planar [fold angles of 5.4 (3) and 9.7 (3)°], as would be expected for its behaving almost entirely as a donor to a high-oxidation-state metal center. The slight fold in each anthracene ligand gives rise to slightly longer Co—C bond lengths to the ring junction carbon atoms than to the other four. Each CoIII cation is further coordinated by three Sn(CH3)3 ligands, giving each mol­ecule a three-legged piano-stool geometry. In each of the two independent mol­ecules, the trio of SnMe3 ligands are modeled as disordered over two positions, rotated by approximately 30%, such that the C atoms nearly overlap. In one mol­ecule, the disorder ratio refined to 0.9365 (8):0.0635 (8), while that for the other refined to 0.9686 (8):0.0314 (8). The mol­ecules are well separated, and thus no significant inter­molecular inter­actions are observed. The compound is of inter­est as the first structure report of an η6-anthracene cobalt(III) complex. PMID:25484731

  9. Caribbean yellow band disease compromises the activity of catalase and glutathione S-transferase in the reef-building coral Orbicella faveolata exposed to anthracene.

    PubMed

    Montilla, Luis Miguel; Ramos, Ruth; García, Elia; Cróquer, Aldo

    2016-05-01

    Healthy and diseased corals are threatened by different anthropogenic sources, such as pollution, a problem expected to become more severe in the near future. Despite the fact that coastal pollution and coral diseases might represent a serious threat to coral reef health, there is a paucity of controlled experiments showing whether the response of diseased and healthy corals to xenobiotics differs. In this study, we exposed healthy and Caribbean yellow band disease (CYBD)-affected Orbicella faveolata colonies to 3 sublethal concentrations of anthracene to test if enzymatic responses to this hydrocarbon were compromised in CYBD-affected tissues. For this, a 2-factorial fully orthogonal design was used in a controlled laboratory bioassay, using tissue condition (2 levels: apparently healthy and diseased) and pollutant concentration (4 levels: experimental control, 10, 30 and 100 ppb concentration) as fixed factors. A permutation-based ANOVA (PERMANOVA) was used to test the effects of condition and concentration on the specific activity of 3 enzymatic biomarkers: catalase, glutathione S-transferase, and glutathione peroxidase. We found a significant interaction between the concentration of anthracene and the colony condition for catalase (Pseudo-F = 3.84, df = 3, p < 0.05) and glutathione S-transferase (Pseudo-F = 3.29, df = 3, p < 0.05). Moreover, our results indicated that the enzymatic response to anthracene in CYBD-affected tissues was compromised, as the activity of these enzymes decreased 3- to 4-fold compared to healthy tissues. These results suggest that under a potential scenario of increasing hydrocarbon coastal pollution, colonies of O. faveolata affected with CYBD might become more vulnerable to the deleterious effects of chemical pollution. PMID:27137073

  10. Unimolecular dissociation of anthracene and acridine cations: The importance of isomerization barriers for the C{sub 2}H{sub 2} loss and HCN loss channels

    SciTech Connect

    Johansson, H. A. B.; Zettergren, H.; Holm, A. I. S.; Haag, N.; Schmidt, H. T.; Cederquist, H.; Nielsen, S. Broendsted; Wyer, J. A.; Kirketerp, M.-B. S.; Stoechkel, K.; Hvelplund, P.

    2011-08-28

    The loss of C{sub 2}H{sub 2} is a low activation energy dissociation channel for anthracene (C{sub 14}H{sub 10}) and acridine (C{sub 13}H{sub 9}N) cations. For the latter ion another prominent fragmentation pathway is the loss of HCN. We have studied these two dissociation channels by collision induced dissociation experiments of 50 keV anthracene cations and protonated acridine, both produced by electrospray ionization, in collisions with a neutral xenon target. In addition, we have carried out density functional theory calculations on possible reaction pathways for the loss of C{sub 2}H{sub 2} and HCN. The mass spectra display features of multi-step processes, and for protonated acridine the dominant first step process is the loss of a hydrogen from the N site, which then leads to C{sub 2}H{sub 2}/HCN loss from the acridine cation. With our calculations we have identified three pathways for the loss of C{sub 2}H{sub 2} from the anthracene cation, with three different cationic products: 2-ethynylnaphthalene, biphenylene, and acenaphthylene. The third product is the one with the overall lowest dissociation energy barrier. For the acridine cation our calculated pathway for the loss of C{sub 2}H{sub 2} leads to the 3-ethynylquinoline cation, and the loss of HCN leads to the biphenylene cation. Isomerization plays an important role in the formation of the non-ethynyl containing products. All calculated fragmentation pathways should be accessible in the present experiment due to substantial energy deposition in the collisions.

  11. Overcoming doxorubicin-resistance in the NCI/ADR-RES model cancer cell line by novel anthracene-9,10-dione derivatives.

    PubMed

    Sangthong, Supranee; Ha, Helen; Teerawattananon, Thapong; Ngamrojanavanich, Nattaya; Neamati, Nouri; Muangsin, Nongnuj

    2013-11-15

    Overcoming drug resistance with remarkable cytotoxic activity by anthracene-9,10-dione derivatives would offer a potential therapeutic strategy. In this study, we report the synthesis and the cytotoxicity of a novel set of anthraquninones. (4-(4-Aminobenzylamino)-9,10-dioxo-9,10-dihydroanthracen-1-yl-4-methylbenzenesulfonate) (3) has excellent in vitro cytotoxicity against doxorubicin-resistant cancer cell line (IC50=0.8 μM), 20-fold higher than doxorubicin. The cytotoxic effect via G2/M arrest does not appear to be ROS.

  12. Theoretical study of the electronically excited radical cations of naphthalene and anthracene as archetypal models for astrophysical observations. Part II. Dynamics consequences.

    PubMed

    Ghanta, S; Reddy, V Sivaranjana; Mahapatra, S

    2011-08-28

    Nuclear dynamics is investigated theoretically from first principles by employing the ab initio vibronic models of the prototypical naphthalene and anthracene radical cations developed in Part I. This Part is primarily aimed at corroborating a large amount of available experimental data with a specific final goal to establish an unambiguous link with the current observations in astrophysics and astronomy. The detailed analyses presented here perhaps establish that these two prototypical polycyclic aromatic hydrocarbon radical cations are indeed potential carriers of the observed diffuse interstellar bands. PMID:21750791

  13. Hormone dependency of chromosome aberrations induced by 7,12-dimethylbenz(a)anthracene in rat bone marrow cells: site-specific increase by erythropoietin

    SciTech Connect

    Ueda, N.; Suglyama, T.; Chattopadhyay, S.C.; Goto-Mimura, K.; Maeda, S.

    1981-08-01

    The frequency of chromosome aberrations (CA) 6 hours after iv injection of 50 mg 7,12-dimethylbenz(a)anthracene (DMBA0/kg was studied in bone marrow cells of the noninbred Long-Evans rat under various hematopoietic conditions. The percentage of metaphase cells with CA was enhanced by anemia and suppressed by polycythemia. The low incidence of CA in polycythemic rats was reversed by 6 U of sheep erythropoietin (EP) injected at the time of DMBA treatment. The interchromosomal and intrachromosomal distribution of CA indicated that hematopoietic stimuli, more specifically EP, greatly enhanced DMBA-induced CA in specific chromosomal regions.

  14. Percutaneous absorption of (7. 10-/sup 14/C)benzo(a)pyrene and (7,12-/sup 14/C)dimethylbenz(a)anthracene in mice

    SciTech Connect

    Sanders, C.L.; Skinner, C.; Gelman, R.A.

    1984-04-01

    The percutaneous penetration, tissue distribution, and excretion of /sup 14/C-labeled benzo(a)pyrene (BaP) and dimethylbenz(a)anthracene (DMBA) were studied in mice. Both BaP and DMBA rapidly penetrated the skin and were excreted more in the feces than in the urine. The proportion of BaP or DMBA absorbed was less with increasing applied dose due to apparent saturation of the uptake process. Uptake from the dorsal skin of the nose was similar to uptake from the dorsal nuchal skin. 24 references.

  15. Driving voltage reduction in white organic light-emitting devices from selectively doping in ambipolar blue-emitting layer

    NASA Astrophysics Data System (ADS)

    Hsiao, Chih-Hung; Lin, Chi-Feng; Lee, Jiun-Haw

    2007-11-01

    White organic light-emitting devices (OLEDs) consisting of ambipolar 9,10-bis(2'-naphthyl) anthracene (ADN) as a host of blue-emitting layer (EML) were investigated. A thin codoped layer of yellow 5,6,11,12-Tetraphenylnaphthacene (rubrene) served as a probe for detecting the position of maximum recombination rate in the 4,4'-bis[2-(4-(N,N-diphenylamino)phenyl)vinyl]biphenyl (DPAVBi) doped-ADN EML. Due to the energy barrier and bipolar carrier transport, the maximum recombination rate was found to be close to but not exactly at the interface of the hole-transporting layer and the EML. With appropriate tuning in the thickness, position, and dopant concentrations of the codoped layer (rubrene:DPAVBi:ADN) in the EML, the device driving voltage decreased by 21.7%, nearly 2 V in reduction, due to the increased recombination current from the faster exciton relaxation induced by the yellow dopants. Among the advantages of introducing the codoped layer over conventional single-doped layers are the elimination of the trapping effect to avoid increasing the device driving voltage, the alleviation of the dependence of the recombination zone on the applied voltage for improving color stability, and the utilization of excitons in a more efficient way to enhance device efficiency. Without using any electrically conductive layers such as the p-i-n structure, we were able to successfully generate 112 cd/m2 at 4 V from our white OLED simply by engineering the structure of the EML.

  16. 7,12-Dimethylbenz[a]anthracene exposure induces the DNA repair response in neonatal rat ovaries

    SciTech Connect

    Ganesan, Shanthi Bhattacharya, Poulomi Keating, Aileen F.

    2013-11-01

    7,12-Dimethylbenz[a]anthracene (DMBA) destroys ovarian follicles at all stages of development. This study investigated DMBA-induced DNA double strand break (DSB) formation with subsequent activation of the ovarian DNA repair response in models of pre-antral or pre-ovulatory follicle loss. Postnatal day (PND) 4 Fisher 344 (F344) rat ovaries were cultured for 4 days followed by single exposures of vehicle control (1% DMSO) or DMBA (12.5 nM or 75 nM) and maintained in culture for 4 or 8 days. Alternately, PND4 F344 rat ovaries were exposed to 1 μM DMBA at the start of culture for 2 days. Total RNA or protein was isolated, followed by qPCR or Western blotting to quantify mRNA or protein level, respectively. γH2AX and phosphorylated ATM were localized and quantified using immunofluorescence staining. DMBA exposure increased caspase 3 and γH2AX protein. Additionally, DMBA (12.5 nM and 1 μM) increased levels of mRNA encoding Atm, Xrcc6, Brca1 and Rad51. In contrast, Parp1 mRNA was decreased on d4 and increased on d8 of DMBA exposure, while PARP1 protein increased after 8 days of DMBA exposure. Total ATM increased in a concentration-dependent temporal pattern (75 nM d4; 12.5 nM d8), while pATM was localized in large primary and secondary follicles and increased after 8 days of 75 nM DMBA exposure compared to both control and 12.5 nM DMBA. These findings support that, despite some concentration effects, DMBA induces ovarian DNA damage and that DNA repair mechanisms are induced as a potential mechanism to prevent follicle loss. - Highlights: • DMBA exposure increases ovarian caspase-3 protein expression. • DMBA exposure increases the γH2AX protein in oocytes. • DMBA exposure activates a DNA repair response in the ovary.

  17. Impact of 7,12-dimethylbenz[a]anthracene exposure on connexin gap junction proteins in cultured rat ovaries

    SciTech Connect

    Ganesan, Shanthi Keating, Aileen F.

    2014-01-15

    7,12-Dimethylbenz[a]anthracene (DMBA) destroys ovarian follicles in a concentration-dependent manner. The impact of DMBA on connexin (CX) proteins that mediate communication between follicular cell types along with pro-apoptotic factors p53 and Bax were investigated. Postnatal day (PND) 4 Fisher 344 rat ovaries were cultured for 4 days in vehicle medium (1% DMSO) followed by a single exposure to vehicle control (1% DMSO) or DMBA (12.5 nM or 75 nM) and cultured for 4 or 8 days. RT-PCR was performed to quantify Cx37, Cx43, p53 and Bax mRNA level. Western blotting and immunofluorescence staining were performed to determine CX37 or CX43 level and/or localization. Cx37 mRNA and protein increased (P < 0.05) at 4 days of 12.5 nM DMBA exposure. Relative to vehicle control-treated ovaries, mRNA encoding Cx43 decreased (P < 0.05) but CX43 protein increased (P < 0.05) at 4 days by both DMBA exposures. mRNA expression of pro-apoptotic p53 was decreased (P < 0.05) but no changes in Bax expression were observed after 4 days of DMBA exposures. In contrast, after 8 days, DMBA decreased Cx37 and Cx43 mRNA and protein but increased both p53 and Bax mRNA levels. CX43 protein was located between granulosa cells, while CX37 was located at the oocyte cell surface of all follicle stages. These findings support that DMBA exposure impacts ovarian Cx37 and Cx43 mRNA and protein prior to both observed changes in pro-apoptotic p53 and Bax and follicle loss. It is possible that such interference in follicular cell communication is detrimental to follicle viability, and may play a role in DMBA-induced follicular atresia. - Highlights: • DMBA increases Cx37 and Cx43 expression prior to follicle loss. • During follicle loss both Cx37 and Cx43 expressions are reduced. • CX43 protein is absent in follicle remnants lacking an oocyte.

  18. Protective role for ovarian glutathione S-transferase isoform pi during 7,12-dimethylbenz[a]anthracene-induced ovotoxicity

    SciTech Connect

    Bhattacharya, Poulomi Keating, Aileen F.

    2012-04-15

    7,12-Dimethylbenz[a]anthracene (DMBA) destroys ovarian follicles at all developmental stages. This study investigated a role for the glutathione S-transferase (Gst) isoforms alpha (a), mu (m) and pi (p) and the transcription factors, Ahr and Nrf2, during DMBA-induced ovotoxicity, and their regulation by phosphatidylinositol-3 kinase (PI3K) signaling. Negative regulation of JNK by GSTP during DMBA exposure was also studied. Post-natal day (PND) 4 Fischer 344 rat ovaries were exposed to vehicle control (1% DMSO) ± DMBA (1 μM) or vehicle control (1% DMSO) ± LY294002 (PI3K inhibitor; 20 μM) for 1, 2, 4, or 6 days. Total RNA or protein was isolated, followed by RT-PCR or Western blotting to determine mRNA or protein level, respectively. Immunoprecipitation using an anti-GSTP antibody was performed to determine interaction between GSTP and JNK, followed by Western blotting to determine JNK and p-c-Jun protein level. DMBA had no impact on Gsta, Gstm or Nrf2 mRNA level, but increased Gstp mRNA and protein after 2 days. Ahr mRNA and protein increased after 2 and 4 days of DMBA exposure, respectively and DMBA increased NRF2 protein level after 4 days. JNK bound to GSTP was increased during DMBA exposure, with a concomitant decrease in unbound JNK and p-c-Jun. Ahr and Gstp mRNA were decreased (2 days) and increased (4 days) by PI3K inhibition, while Gstm mRNA increased (P < 0.05) after both time points, and there was no effect on Nrf2 mRNA. PI3K inhibition increased AHR, NRF2 and GSTP protein level. These findings support involvement of ovarian GSTP during DMBA exposure, and indicate a regulatory role for the PI3K signaling pathway on ovarian xenobiotic metabolism gene expression. -- Highlights: ► Ovarian GSTP is activated in response to DMBA exposure. ► AhR and Nrf2 transcription factors are up-regulated by DMBA. ► PI3K signaling regulates Ahr, Nrf2 and Gstp expression. ► GSTP negatively regulates ovarian JNK in response to DMBA exposure.

  19. Synthesis and biological evaluation of 2,6-di(furan-3-yl)anthracene-9, 10-dione as an inhibitor of human protein kinase CK2.

    PubMed

    Haidar, S; Meyers, A; Bollacke, A; Jose, J

    2015-12-01

    Protein kinase CK2 is an emerging target for the therapeutic intervention in human diseases, in particular in cancer. Inhibitors of this enzyme are at current in clinical trials indicating its drug ability. Here we report on the synthesis of two derivatives of 2,6-diaryl-anthracene-9,10-dione, one of them, 2,6-di(furan-3-yl)anthracene-9,10-dione (3), turned out to be active towards CK2, and ATP competitive with an IC50 value of 2.35 μM and a K(i) value of 1.26 μM. Molecular modeling studies were performed to explain the binding affinity of compound 3 in comparison to emodin. These indicated that unlike emodin, compound 3 was not able to perform a hydrogen bond with Lys68, although the compound fits well in the active site of human CK2α, which explains the difference in the measured affinity between those two compounds.

  20. Full-dimensional multilayer multiconfigurational time-dependent Hartree study of electron transfer dynamics in the anthracene/C60 complex

    SciTech Connect

    Xie, Yu; Zheng, Jie; Lan, Zhenggang

    2015-02-28

    Electron transfer at the donor-acceptor heterojunctions plays a critical role in the photoinduced process during the solar energy conversion in organic photovoltaic materials. We theoretically investigate the electron transfer process in the anthracene/C60 donor-acceptor complex by using quantum dynamics calculations. The electron-transfer model Hamiltonian with full dimensionality was built by quantum-chemical calculations. The quantum dynamics calculations were performed using the multiconfigurational time-dependent Hartree (MCTDH) theory and multilayer (ML) MCTDH methods. The latter approach (ML-MCTDH) allows us to conduct the comprehensive study on the quantum evolution of the full-dimensional electron-transfer model including 4 electronic states and 246 vibrational degrees of freedom. Our quantum dynamics calculations exhibit the ultrafast anthracene → C60 charge transfer process because of the strong coupling between excitonic and charge transfer states. This work demonstrates that the ML-MCTDH is a very powerful method to treat the quantum evolution of complex systems.

  1. Determination of the Residual Anthracene Concentration in Cultures of Haloalkalitolerant Actinomycetes by Excitation Fluorescence, Emission Fluorescence, and Synchronous Fluorescence: Comparative Study

    PubMed Central

    Lara-Severino, Reyna del Carmen; Camacho-López, Miguel Ángel; García-Macedo, Jessica Marlene; Gómez-Oliván, Leobardo M.; Sandoval-Trujillo, Ángel H.; Isaac-Olive, Keila; Ramírez-Durán, Ninfa

    2016-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are compounds that can be quantified by fluorescence due to their high quantum yield. Haloalkalitolerant bacteria tolerate wide concentration ranges of NaCl and pH. They are potentially useful in the PAHs bioremediation of saline environments. However, it is known that salinity of the sample affects fluorescence signal regardless of the method. The objective of this work was to carry out a comparative study based on the sensitivity, linearity, and detection limits of the excitation, emission, and synchronous fluorescence methods, during the quantification of the residual anthracene concentration from the following haloalkalitolerant actinomycetes cultures Kocuria rosea, Kocuria palustris, Microbacterium testaceum, and 4 strains of Nocardia farcinica, in order to establish the proper fluorescence method to study the PAHs biodegrading capacity of haloalkalitolerant actinobacteria. The study demonstrated statistical differences among the strains and among the fluorescence methods regarding the anthracene residual concentration. The results showed that excitation and emission fluorescence methods performed very similarly but sensitivity in excitation fluorescence is slightly higher. Synchronous fluorescence using Δλ = 150 nm is not the most convenient method. Therefore we propose the excitation fluorescence as the fluorescence method to be used in the study of the PAHs biodegrading capacity of haloalkalitolerant actinomycetes. PMID:26925294

  2. Synthesis and antitumor mechanisms of a copper(II) complex of anthracene-9-imidazoline hydrazone (9-AIH).

    PubMed

    Qin, Qi-Pin; Liu, Yan-Cheng; Wang, Hai-Lu; Qin, Jiao-Lan; Cheng, Feng-Jie; Tang, Shang-Feng; Liang, Hong

    2015-07-01

    A new anthracycline derivative, anthracene-9-imidazoline hydrazone (9-AIH), was synthesized and selected as an antitumor ligand to afford a copper(II) complex of 9-AIH, cis-[Cu(II)Cl2(9-AIH)] (1). Complex 1 was structurally characterized by IR, elemental analysis, ESI-MS and single crystal X-ray diffraction analysis. By MTT assay, it was revealed that 1 showed overall a higher in vitro cytotoxicity than 9-AIH towards a panel of human tumour cell lines, with IC50 values from 0.94–3.68 μM, in which the BEL-7404 cell line was the most sensitive to 1. By spectral analyses and gel electrophoresis, the DNA binding affinity of 9-AIH and 1 was determined. 9-AIH was suggested to bind with DNA in an intercalative mode, with a quenching constant of 1.04 × 10(4) M(−1) on the EB–DNA complex. While for 1, both intercalative and covalent binding modes were suggested. By flow cytometry, 1 was found to block the cell cycle of BEL-7404 cells in a dose-dependent mode, in which it induced the G2/M phase arrest at 0.5 μM and induced the S phase arrest at higher concentrations of 1.0 or 2.0 μM. From the cellular morphological observations under different fluorescence probe staining, a dose-dependent manner of 1 to induce cell apoptosis in the late stage was suggested. Comparatively, equivalent apoptotic cells, respectively, in the early and late stages were found when incubated with 2.0 μM of 9-AIH. The mitochondrial membrane potential measured by JC-1 staining and the ROS generation in cells detected using a DCFH-DA probe suggested that the cell apoptosis induced by 1 might undergo the ROS-related mitochondrial pathway. Accordingly, the mutant p53 expression was found to be suppressed and the caspase cascade (caspase-9/3) was consequently activated by 1. This action mechanism for 1 in the BEL-7404 cells was unique and was not found in the presence of 9-AIH under the same conditions, indicating their different antitumor mechanism. Furthermore, the in vivo acute toxicity of 1

  3. Effect of Side Chains on Molecular Conformation of Anthracene-Ethynylene-Phenylene-Vinylene Oligomers: A Comparative Density Functional Study With and Without Dispersion Interaction.

    PubMed

    Dong, Chuanding; Hoppe, Harald; Beenken, Wichard J D

    2016-06-01

    Using density functional calculations with and without dispersion interaction, we studied the effects of linear octyl and branched 2-ethylhexyl side chains on the oligomer conformation of the conjugated copolymer poly(p-anthracene-ethynylene)-alt-poly(p-phenylene-vinylene). With dispersion included, the branched side chains can cause significant bending of the oligomer backbone, while without dispersion they induce mainly torsional disorder. The oligomers with mainly linear side chains keep good planarity when optimized with and without dispersion. Despite their dramatically different conformations, the calculated absorption spectra of the oligomers with various side chain combinations are very similar, indicating that the conformation of the copolymer is not the main reason for the experimentally observed different spectra of ordered and disordered phases.

  4. Anthracene-9, 10-dione derivatives induced apoptosis in human cervical cancer cell line (CaSki) by interfering with HPV E6 expression.

    PubMed

    Sangthong, Supranee; Sangphech, Naunpun; Palaga, Tanapat; Ngamrojanavanich, Nattaya; Puthong, Songchan; Vilaivan, Tirayut; Muangsin, Nongnuj

    2014-04-22

    A new series of anthracene-9, 10-dione derivatives have been synthesized to increase cytotoxic activity against human papillomavirus (HPV) positive cancer cell line, CaSki. The highest cytotoxicity was achieved by 4-(benzylamino)-9,10-dioxo-4a,9,9a,10-tetrahydroanthracen-1-yl 4-ethylbenzenesulfonate (5) with the inhibitory concentration 50 (IC50) of 0.3 μM which is 20 times lower than that of cisplatin (CDDP; IC50 = 8.0 μM). The toxicity against non-cancerous cell line, WI-38, was low with the IC50 > 10 μM. Treatment with this compound resulted in decreasing HPV E6 expression. Furthermore, increasing p53 and decreasing Bcl-2 expression were noted. Cell cycle profiles revealed an accumulation of cells in the G2/M phase.

  5. Experimental and computer graphics simulation analyses of the DNA interaction of 1,8-bis-(2-diethylaminoethylamino)-anthracene-9,10-dione, a compound modelled on doxorubicin.

    PubMed

    Islam, S A; Neidle, S; Gandecha, B M; Brown, J R

    1983-09-15

    The crystal structure of the anthraquinone derivative 1,8-bis-(2-diethylaminoethylamino)-anthracene-9,10-dione has been established. This compound was prepared as a potential DNA-intercalating agent based on the proven intercalators doxorubicin and mitoxantrone. Its DNA-binding properties have been examined experimentally by spectroscopic, thermal denaturation and ccc-DNA unwinding techniques: the results are consistent with an intercalative mode of binding to DNA. Computer graphics stimulation of the intercalative docking of this compound into the self-complementary dimer of d(CpG) has provided a minimum energy geometrical arrangement for the bound drug in the intercalation site comparable to that for proflavine when intercalated into the same d(CpG) model system. Entry of the compound into the site can only occur via the major groove.

  6. Induction of mammary tumors in aging rats by 7,12-dimethylbenz(a)anthracene: role of DNA synthesis during carcinogenesis

    SciTech Connect

    Sinha, D.K.; Dao, T.L.

    1980-03-01

    Two routes of administration were used to test the susceptibility of the mammary gland of the rat to 7,12-dimethylbenz(a)anthracene (DMBA) carcinogenesis in relation to age of the tissue. In one series of experiments, 60-, 70-, 90-, 120-, 150-, and 200-day-old female nonbred Sprague-Dawley rats were given DMBA iv. In parallel experiments, rats of the same ages as those above were given DMBA by local application. Mammary tumors developed in 89 to 90% of the 60- and 70-day-old rats and in 40% of the 90-day-old rats. Rats 120 days old and older were completely refractory to DMBA. In contrast, all rats, irrespective of their ages, developed tumors when DMBA was applied locally. DMBA given iv significantly inhibited DNA synthesis in mammary glands, but DMBA applied locally significantly increased the Li of the mammary glands.

  7. DNA binding and adduct formation of 7,12-dimethylbenz(a)-anthracene by rat mammary epithelial cell aggregates in vitro

    SciTech Connect

    Singletary, K.W.; Milner, J.A.

    1986-01-01

    Freshly isolated mammary epithelial cell aggregates from female Sprague-Dawley rats metabolized 7,12-dimethylbenz-(a)anthracene (DMBA) to bay-region anti- and syn-dihydrodiolepoxides that bound to deoxyguanosine and deoxyadenosine residues in cellular DNA. After 24 h of incubation 68% of the DMBA (0.4 micrograms/ml) was metabolized and 58% of the extracellular metabolites were water-soluble. DMBA-DNA binding increased rapidly during the initial 24 h of incubation. Formation of the bay-region syn-dihydrodiolepoxide:deoxyadenosine adduct increased linearly throughout the 24 h, whereas formation of deoxyadenosine and deoxyguanosine adducts with the bay-region anti-dihydrodiolepoxide increased rapidly following a delay of 12 h.

  8. 7,12-dimethylbenz(a)anthracene-induced DNA binding and repair synthesis in susceptible and nonsusceptible mammary epithelial cells in culture. [Rats

    SciTech Connect

    Tay, L.K.; Russo, J.

    1981-07-01

    The effect of age and parity on the binding of 7,12-dimethylbenz(a)anthracene (DMBA) to DNA and the repair of DMBA-damaged DNA have been demonstrated in logarithmic phase and confluent mammary epithelial cell cultures from young virgin (YV), old virgin (OV), and parous (P) noninbred and inbred Sprague-Dawley rats. Excision repair was determined by measuring, in the presence of hydroxyurea and 5-bromodeoxyuridine, tritiated thymidine incorporation into DNA during the repair process. These results suggest that age and parity not only lower the binding of DMBA to mammary epithelial cell DNA but also increase the efficiency of DNA repair processes, which may explain the lower susceptibility of OV and P rats to DMBA-induced mammary carcinogenesis.

  9. Analysis of the near-edge X-ray-absorption fine-structure of anthracene: A combined theoretical and experimental study

    SciTech Connect

    Klues, Michael; Witte, Gregor; Hermann, Klaus

    2014-01-07

    The near-edge fine structure of the carbon K-edge absorption spectrum of anthracene was measured and theoretically analyzed by density functional theory calculations implemented in the StoBe code. It is demonstrated that the consideration of electronic relaxation of excited states around localized core holes yields a significant improvement of the calculated excitation energies and reproduces the experimentally observed fine structure well. The detailed analysis of excitation spectra calculated for each symmetry inequivalent excitation center allows in particular to examine the influence of chemical shifts and core hole effects on the excitation energies. Moreover, the visualization of final states explains the large variations in the oscillator strength of various transitions as well as the nature of Rydberg-states that exhibit a notable density of states below the ionization potentials.

  10. Anthracene/phenothiazine π-conjugated sensitizers for dye-sensitized solar cells using redox mediator in organic and water-based solvents.

    PubMed

    Lin, Ryan Yeh-Yung; Chuang, Tzu-Man; Wu, Feng-Ling; Chen, Pei-Yu; Chu, Te-Chun; Ni, Jen-Shyang; Fan, Miao-Syuan; Lo, Yih-Hsing; Ho, Kuo-Chuan; Lin, Jiann T

    2015-01-01

    Metal-free dyes (MD1 to MD5) containing an anthracene/phenothiazine unit in the spacer have been synthesized. The conversion efficiency (7.13 %) of the dye-sensitized solar cell using MD3 as the sensitizer reached approximately 85 % of the N719-based standard cell (8.47 %). The cell efficiency (8.42 %) of MD3-based dye-sensitized solar cells (DSSCs) with addition of chenodeoxycholic acid is comparable with that of N719-based standard cell. The MD3 water-based DSSCs using a dual-TEMPO (2,2,6,6-tetramethylpiperidine-N-oxyl)/iodide electrolyte exhibited very promising cell performance of 4.96 % with an excellent Voc of 0.77 V.

  11. A new fluorescent enhanced probe based on (E)-9-(2-nitrovinyl)-anthracene for the detection of bisulfite anions and its practical application

    NASA Astrophysics Data System (ADS)

    Chao, Jianbin; Liu, Yuhong; Zhang, Yan; Zhang, Yongbin; Huo, Fangjun; Yin, Caixia; Wang, Yu; Qin, Liping

    2015-07-01

    A new fluorescent enhanced probe based on (E)-9-(2-nitrovinyl)-anthracene is developed, which shows high selectivity and sensitivity for the detection of bisulfite anions at Na2HPO4 citric acid buffer solutions (pH 5.0). When addition of HSO3-, the fluorescence intensity is significantly enhanced and the probe displays apparent fluorescence color changes from non-fluorescence to blue under a UV lamp illumination, the solution color also changes from yellow to colorless. The detection limit is determined to be as low as 6.30 μM. This offers another specific colorimetric and fluorescent probe for bisulfite anions detection, furthermore it is applied in detecting the level of bisulfite in sugar samples.

  12. Catalytic effect of gallium chloride in the diels-alder reaction between maleic anhydride and its derivatives and unsubstituted and substituted anthracenes

    SciTech Connect

    Kiselev, V.D.; Konovalov, A.I.; Shakirov, I.M.

    1985-11-10

    The stability of n, v complexes between gallium chloride and unsubstituted and substituted maleic anhydrides was determined in benzene by a thermochemical method; it was shown that the stability of the complexes decreases in the transition from maleic anhydrides with electron-donating substituents to maleic anhydrides with electron-withdrawing substituents. The reactivity of these dienophiles in the uncatalyzed Diels-Alder reactions with unsubstituted and substituted anthracenes in benzene and in the reactions catalyzed by gallium chloride was studied. The reactivity of the dienophiles varies similarly in the reactions with the investigated dienes, and this rules out treatment of steric hindrances as the reason for the reduced reactivity of the substituted dienophiles. A decrease in the catalytic effect was observed for the unreactive diene-dienophile pairs.

  13. Photophysical properties of some fluorescent materials containing 3-methoxy-7H-benzo[de]anthracen-7-one embedded in sol-gel silica hybrids

    NASA Astrophysics Data System (ADS)

    Raditoiu, Alina; Raditoiu, Valentin; Culita, Daniela Cristina; Baran, Adriana; Anghel, Dan Florin; Spataru, Catalin Ilie; Amariutei, Viorica; Nicolae, Cristian Andi; Wagner, Luminita Eugenia

    2015-07-01

    Several fluorescent materials were prepared by embedding 3-methoxy-7H-benzo[de]anthracen-7-one in transparent sol-gel silica hybrids, in acid catalysis and at room temperature. The photophysical properties of the materials are studied in relationship with the structure and based on interactions established between the fluorophore, which display high sensitivity to minor changes in the local environments, and hybrid silica networks. Colored materials show marked differences in absorption and fluorescence spectra due to the environments around the dyestuff molecules created in the host matrices by grafting different organic moieties onto silica surface. The fluorescence emission spectrum of the obtained materials reveals a positive solvatochromism due to the intramolecular charge transfer character of the excited states and changes in the fluorophore dipole moment. Variations recorded in the fluorescence parameters of the hybrid materials confirm that some interactions are established between the fluorescent dyestuff and hybrid silica network.

  14. Therapeutic effect of centchroman alone and in combination with glycine soya on 7,12-dimethylbenz[alpha]anthracene-induced breast tumor in rat.

    PubMed

    Mishra, Rajeev; Tiwari, Ashutosh; Bhadauria, Smrati; Mishra, Jyoti; Murthy, P K; Murthy, P S R

    2010-06-01

    Centchroman is a non-steroidal oral contraceptive and has been found to be a candidate drug for breast cancer exhibiting partial to complete remission of lesions in 40.5% of breast cancer patients. The therapeutic efficacy of centchroman was monitored alone and together with glycine soya on growth of 7,12-dimethylbenz[alpha]anthracene-induced breast tumor in rat. The tumor regression was monitored at different doses of centchroman alone ranging from 0 to 10 mg kg(-1) and with glycine soya from 1x10(4) to 5x10(4) mg kg(-1) per day until 5weeks treatment. An optimum tumor treatment opus was established with varying treatment parameters including doses of therapeutic agents and treatment period. The tumors were found to be static with a strong anti-estrogenic effect. Overall our study shows that both centchroman and glycine soya alone and jointly combat with breast cancer.

  15. Further metabolism of diol-epoxides of chrysene and dibenz[a,c]anthracene to DNA binding species as evidenced by 32P-postlabelling analysis.

    PubMed

    Hall, M; Parker, D K; Hewer, A J; Phillips, D H; Grover, P L

    1988-05-01

    Incubation of r-1,t-2-dihydroxy-t-3,4-oxy-1,2,3,4-tetrahydrochrysene (anti-chrysene-1,2-diol 3,4-oxide), the bay-region diol-epoxide of chrysene, with rat liver microsomes in the presence of NADP+ and DNA, followed by 32P-postlabelling analysis of the DNA, revealed the presence of at least two adducts not detected when anti-chrysene-1,2-diol 3,4-oxide was incubated with DNA alone. The formation of these adducts was not blocked by the epoxide hydrolase inhibitor 1,1,1-trichloropropane-2,3-oxide. One of the adducts cochromatographed with the adduct spot obtained when authentic 9-hydroxy-r-1,t-2-dihydroxy-t-3,4-oxy-1,2,3,4-tetrahydrochrysene (anti-9-OH-chrysene-1,2-diol 3,4-oxide) was reacted with DNA. Evidence suggested that a second adduct could also be formed by further metabolism of anti-9-OH-chrysene-1,2-diol 3,4-oxide. In addition, evidence was obtained for the further metabolism of the syn-isomer of chrysene 1,2-diol 3,4-oxide and the anti-isomer of a non-bay-region diol-epoxide of dibenz[a,c]anthracene to DNA binding species, but not for that of either the anti- or syn-isomers of the bay-region diol-epoxide of benzo[a]pyrene, the anti-isomers of the bay-region or a non-bay-region diol-epoxide of benz[a]anthracene, or the anti-isomer of the bay-region diol-epoxide of benzo[b]fluoranthene.

  16. Vertical and adiabatic excitations in anthracene from quantum Monte Carlo: Constrained energy minimization for structural and electronic excited-state properties in the JAGP ansatz

    NASA Astrophysics Data System (ADS)

    Dupuy, Nicolas; Bouaouli, Samira; Mauri, Francesco; Sorella, Sandro; Casula, Michele

    2015-06-01

    We study the ionization energy, electron affinity, and the π → π∗ (1La) excitation energy of the anthracene molecule, by means of variational quantum Monte Carlo (QMC) methods based on a Jastrow correlated antisymmetrized geminal power (JAGP) wave function, developed on molecular orbitals (MOs). The MO-based JAGP ansatz allows one to rigorously treat electron transitions, such as the HOMO → LUMO one, which underlies the 1La excited state. We present a QMC optimization scheme able to preserve the rank of the antisymmetrized geminal power matrix, thanks to a constrained minimization with projectors built upon symmetry selected MOs. We show that this approach leads to stable energy minimization and geometry relaxation of both ground and excited states, performed consistently within the correlated QMC framework. Geometry optimization of excited states is needed to make a reliable and direct comparison with experimental adiabatic excitation energies. This is particularly important in π-conjugated and polycyclic aromatic hydrocarbons, where there is a strong interplay between low-lying energy excitations and structural modifications, playing a functional role in many photochemical processes. Anthracene is an ideal benchmark to test these effects. Its geometry relaxation energies upon electron excitation are of up to 0.3 eV in the neutral 1La excited state, while they are of the order of 0.1 eV in electron addition and removal processes. Significant modifications of the ground state bond length alternation are revealed in the QMC excited state geometry optimizations. Our QMC study yields benchmark results for both geometries and energies, with values below chemical accuracy if compared to experiments, once zero point energy effects are taken into account.

  17. Exploring the interaction of mercury(II) by N(2)S(2) and NS(3) anthracene-containing macrocyclic ligands: photophysical, analytical, and structural studies.

    PubMed

    Tamayo, Abel; Pedras, Bruno; Lodeiro, Carlos; Escriche, Lluis; Casabó, Jaume; Capelo, José Luis; Covelo, Berta; Kivekäs, Raikko; Sillanpää, Reijo

    2007-09-17

    The complexation properties toward Hg(II) of six macrocyclic ligands, 3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,15-triene (L1), 7-(9-anthracenylmethyl)-3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,15-triene (L2), 7-(10-methyl-9-anthracenylmethyl)-3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,15-triene (L3), 7,7'-[9,10-anthracenediylbis(methylene)]bis-3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,15-triene (L4), 1,4,7-trithia-11-azacyclotetradecane (L5), and 11,-(anthracen-9-ylmethyl)-1,4,7-trithia-11-azacyclotetradecane (L6), were studied. The stoichiometries of the formed species were determined from absorption and fluorescence titrations. In these anthracene-containing macrocycles, a fluorescent quenching of the emission was found upon Hg(II) addition. The X-ray crystal structure of [HgCl2(L2)] x 1/2CH2Cl2 was determined. The asymmetric unit contains two independent [HgCl2(L2)] molecules and one dichloromethane molecule. Each Hg(II) ion is coordinated by the pyridine nitrogen, the two sulfur atoms of one L2 molecule, and two chloride ions. Analytical studies using solvent extraction separation of Hg(II) from aqueous solutions were performed to determine the Hg(II) extraction capability of ligands L1, L2, and L5.

  18. Vertical and adiabatic excitations in anthracene from quantum Monte Carlo: Constrained energy minimization for structural and electronic excited-state properties in the JAGP ansatz

    SciTech Connect

    Dupuy, Nicolas; Bouaouli, Samira; Mauri, Francesco Casula, Michele; Sorella, Sandro

    2015-06-07

    We study the ionization energy, electron affinity, and the π → π{sup ∗} ({sup 1}L{sub a}) excitation energy of the anthracene molecule, by means of variational quantum Monte Carlo (QMC) methods based on a Jastrow correlated antisymmetrized geminal power (JAGP) wave function, developed on molecular orbitals (MOs). The MO-based JAGP ansatz allows one to rigorously treat electron transitions, such as the HOMO → LUMO one, which underlies the {sup 1}L{sub a} excited state. We present a QMC optimization scheme able to preserve the rank of the antisymmetrized geminal power matrix, thanks to a constrained minimization with projectors built upon symmetry selected MOs. We show that this approach leads to stable energy minimization and geometry relaxation of both ground and excited states, performed consistently within the correlated QMC framework. Geometry optimization of excited states is needed to make a reliable and direct comparison with experimental adiabatic excitation energies. This is particularly important in π-conjugated and polycyclic aromatic hydrocarbons, where there is a strong interplay between low-lying energy excitations and structural modifications, playing a functional role in many photochemical processes. Anthracene is an ideal benchmark to test these effects. Its geometry relaxation energies upon electron excitation are of up to 0.3 eV in the neutral {sup 1}L{sub a} excited state, while they are of the order of 0.1 eV in electron addition and removal processes. Significant modifications of the ground state bond length alternation are revealed in the QMC excited state geometry optimizations. Our QMC study yields benchmark results for both geometries and energies, with values below chemical accuracy if compared to experiments, once zero point energy effects are taken into account.

  19. Bright white organic light-emitting diodes based on two blue emitters with similar molecular structures

    NASA Astrophysics Data System (ADS)

    Wang, Liduo; Lei, Gangtie; Qiu, Yong

    2005-06-01

    We show that highly efficient and chromatically stable white organic electroluminescent devices can be obtained, based on two blue emitters with similar structures: 9,10-di-(2-naphthyl)-anthracene (ADN) and 9,10-di-(2-naphthyl)-2-terbutyl-anthracene doped with yellow-orange emitting 5,6,11,12-tetraphenylnaphthacene (rubrene) at ultralow doping concentrations (0.01%-0.05%). The relative intensity of the blue and orange-yellow emissions could be fine-tuned by varying the doping concentrations of rubrene in the host to achieve pure white emission. The energy-transfer mechanism of ADN and rubrene with ultralow doping concentrations is discussed in terms of the long exciton diffusion distance of ADN.

  20. The effect of diet, exercise, and 7,12-dimethylbenz(a)anthracene on food intake, body composition, and carcass energy levels in virgin female BALB/c mice

    NASA Technical Reports Server (NTRS)

    Lane, Helen W.; Keith, Robert E.; Strahan, Susan; White, Marguerite T.

    1991-01-01

    The effects of diet, exercise, and 7,12-dimethylbenz(a)anthracene (DMBA), a mammary-tumor carcinogen, on food intake, energy consumption, body weight, and body composition in virgin female BALB/c mice are investigated. Diet, exercise, and DMBA all had pronounced effects on energy consumption, which in turn affected body composition. These treatments may influence manifestations of breast cancer via their effects on body composition.

  1. Time-dependent changes in antioxidative enzyme expression and photosynthetic activity of Chlamydomonas reinhardtii cells under acute exposure to cadmium and anthracene.

    PubMed

    Aksmann, Anna; Pokora, Wojciech; Baścik-Remisiewicz, Agnieszka; Dettlaff-Pokora, Agnieszka; Wielgomas, Bartosz; Dziadziuszko, Małgorzata; Tukaj, Zbigniew

    2014-12-01

    Heavy metals (HM) and polycyclic aromatic hydrocarbons (PAHs) are present in the freshwater environment at concentrations that can be hazardous to the biota. Among HMs and PAHs, cadmium (Cd) and anthracene (ANT) are the most prevalent and toxic ones. The response of Chlamydomonas cells to Cd and ANT at concentrations that markedly reduced the growth of algal population was investigated in this study. At such concentrations, both cadmium and anthracene were recognized as oxidative stress inducers, since high concentration of H2O2 in treated cultures was observed. Therefore, as a part of the "molecular phase" of the cell response to this stress, we examined the time-dependent expression of genes encoding the main antioxidative enzymes: superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX), as well as the activity of these enzymes in cells, with special attention paid to chloroplastic and mitochondrial isoforms of SOD. To characterize the cell response at the "physiological level", we examined the photosynthetic activity of stressed cells via analysis of chlorophyll a fluorescence in vivo. In contrast to standard ecotoxicity studies in which the growth end-points are usually determined, herein we present time-dependent changes in algal cell response to Cd- and ANT-induced stress. The most significant effect(s) of the toxicants on photosynthetic activity was observed in the 6th hour, when strong depression of PI parameter value, an over 50 percent reduction of the active reaction center fraction (RC0) and a 3-fold increase in non-photochemical energy dissipation (DI0/RC) were noted. At the same time, the increase (up to 2.5-fold) in mRNA transcript of SOD and CAT genes, followed by the enhancement in the enzyme activity was observed. The high expression of the Msd 3 gene in treated Chlamydomonas cells probably complements the partial loss of chloroplast Fe-SOD and APX activity, while catalase and Mn-SOD 5 seem to be the major enzymes responsible for

  2. Time-dependent changes in antioxidative enzyme expression and photosynthetic activity of Chlamydomonas reinhardtii cells under acute exposure to cadmium and anthracene.

    PubMed

    Aksmann, Anna; Pokora, Wojciech; Baścik-Remisiewicz, Agnieszka; Dettlaff-Pokora, Agnieszka; Wielgomas, Bartosz; Dziadziuszko, Małgorzata; Tukaj, Zbigniew

    2014-12-01

    Heavy metals (HM) and polycyclic aromatic hydrocarbons (PAHs) are present in the freshwater environment at concentrations that can be hazardous to the biota. Among HMs and PAHs, cadmium (Cd) and anthracene (ANT) are the most prevalent and toxic ones. The response of Chlamydomonas cells to Cd and ANT at concentrations that markedly reduced the growth of algal population was investigated in this study. At such concentrations, both cadmium and anthracene were recognized as oxidative stress inducers, since high concentration of H2O2 in treated cultures was observed. Therefore, as a part of the "molecular phase" of the cell response to this stress, we examined the time-dependent expression of genes encoding the main antioxidative enzymes: superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX), as well as the activity of these enzymes in cells, with special attention paid to chloroplastic and mitochondrial isoforms of SOD. To characterize the cell response at the "physiological level", we examined the photosynthetic activity of stressed cells via analysis of chlorophyll a fluorescence in vivo. In contrast to standard ecotoxicity studies in which the growth end-points are usually determined, herein we present time-dependent changes in algal cell response to Cd- and ANT-induced stress. The most significant effect(s) of the toxicants on photosynthetic activity was observed in the 6th hour, when strong depression of PI parameter value, an over 50 percent reduction of the active reaction center fraction (RC0) and a 3-fold increase in non-photochemical energy dissipation (DI0/RC) were noted. At the same time, the increase (up to 2.5-fold) in mRNA transcript of SOD and CAT genes, followed by the enhancement in the enzyme activity was observed. The high expression of the Msd 3 gene in treated Chlamydomonas cells probably complements the partial loss of chloroplast Fe-SOD and APX activity, while catalase and Mn-SOD 5 seem to be the major enzymes responsible for

  3. Comparative DNA binding of 7,12-dimethylbenz[a]anthracene and some of its metabolites in mouse epidermis in vivo as revealed by the 32P-postlabeling technique.

    PubMed

    Schoepe, K B; Friesel, H; Schurdak, M E; Randerath, K; Hecker, E

    1986-04-01

    The binding of some mouse skin metabolites and related derivatives of the tumor initiator 7,12-dimethylbenz[a]anthracene (DMBA) was investigated by 32P-postlabeling analysis after its topical administration. DMBA and trans-3,4-dihydro-3,4-dihydroxy-DMBA (DMBA-3,4-dihydrodiol) both led to the formation of four DNA adducts, which showed a very similar pattern of spots on thin-layer chromatograms. With trans-8,9-dihydro-8,9-dihydroxy-7,12-dimethylbenz[a]anthracene (DMBA-8,9-dihydrodiol) one major adduct was obtained which was chromatographically indistinguishable from one of the DMBA adducts. In contrast, 7-hydroxymethyl-12-methylbenz[a]anthracene (7-OHM-12-MBA) gave rise to two major adducts which were separable from DMBA adducts. 3-hydroxy-7,12-dimethylbenz[a]anthracene (3-OH-DMBA) and 7,12-dimethylbenz[a]anthracene-7,12-epoxide (DMBA-O2) did not lead to detectable amounts of adducts. Quantitative determination of DNA binding showed that an initiating dose (i = 100 nmol) of DMBA yielded approximately 12 adducts/10(7) normal nucleotides. Adduct formation with the same dose of DMBA-3,4-dihydrodiol was 7-8 times higher. At a 4-fold higher dose level, DMBA-8,9-dihydrodiol exhibited a 3- to 6-times weaker binding and 7-OHM-12-MBA a slightly stronger binding than DMBA. Chromatography of the DMBA and DMBA-3,4-dihydrodiol adducts with a solvent containing borate showed a decreased mobility of two out of four adducts in each case. These adducts were also sensitive to oxidation by periodate. The results suggest that two DMBA adducts carried vicinal cis-hydroxyl groups and thus were probably derived from the anti-3,4-dihydrodiol-1,2-oxide(s) of DMBA. The other two adducts were probably derived from the syn-stereoisomer(s). When the DNA-modifying capabilities and initiating activities of the more prominent mouse-skin metabolites are considered in relation to DMBA, DMBA-3,4-dihydrodiol is postulated to be a proximate and DMBA-3,4-dihydrodiol-1,2-oxide(s) to be ultimate

  4. The effect of gender, sexual maturation and xenobiotic treatment on the formation of hydroxymethyl metabolites from 7, 12-dimethylbenz[a]anthracene in rat liver microsomes.

    PubMed

    Boyle, S P; Craft, J A

    2000-09-30

    The effects of age, gender, strain, phenobarbital (PB) treatment and pituitary influence on the regioselective metabolism of 7, 12-dimethylbenz[a]anthracene to hydroxmethyl metabolites were investigated. Studies used hepatic microsomal membranes from immature and mature Long Evans (LE) rats and adult Hooded Lister (HL) animals. Hydroxymethyl metabolites were resolved by both normal and reverse phase HPLC with on-line diode array detection. The CYP isoform(s) responsible for oxidation at the 12 methyl position exhibited no gender or developmental regulation and the rate of formation was not altered following hypophysectomy. PB-treatment of adult rats caused a significant increase in the rate of formation of both male and female animals (29 and 41-fold, respectively) suggesting a major contribution from a PB-inducible isoform, such as CYP2B. The rate of formation of 7OHMe12MBA exhibited no gender dependency in immature animals but was 2-fold greater than that observed for 12OHMe7MBA suggesting that steric hindrance resulting from the adjacent 1,2 benzyl ring favours substrate oxidation at the 7-methyl position. Male predominant formation of 7OHMe12MBA was apparent following sexual maturation of the LE rats and was significantly reduced upon hypophysectomy suggesting the involvement of a male-specific GH dependent isoform e.g. CYP2C11.

  5. The anharmonic quartic force field infrared spectra of five non-linear polycyclic aromatic hydrocarbons: Benz[a]anthracene, chrysene, phenanthrene, pyrene, and triphenylene

    NASA Astrophysics Data System (ADS)

    Mackie, Cameron J.; Candian, Alessandra; Huang, Xinchuan; Maltseva, Elena; Petrignani, Annemieke; Oomens, Jos; Mattioda, Andrew L.; Buma, Wybren Jan; Lee, Timothy J.; Tielens, Alexander G. G. M.

    2016-08-01

    The study of interstellar polycyclic aromatic hydrocarbons (PAHs) relies heavily on theoretically predicted infrared spectra. Most earlier studies use scaled harmonic frequencies for band positions and the double harmonic approximation for intensities. However, recent high-resolution gas-phase experimental spectroscopic studies have shown that the harmonic approximation is not sufficient to reproduce experimental results. In our previous work, we presented the anharmonic theoretical spectra of three linear PAHs, showing the importance of including anharmonicities into the theoretical calculations. In this paper, we continue this work by extending the study to include five non-linear PAHs (benz[a]anthracene, chrysene, phenanthrene, pyrene, and triphenylene), thereby allowing us to make a full assessment of how edge structure, symmetry, and size influence the effects of anharmonicities. The theoretical anharmonic spectra are compared to spectra obtained under matrix isolation low-temperature conditions, low-resolution, high-temperature gas-phase conditions, and high-resolution, low-temperature gas-phase conditions. Overall, excellent agreement is observed between the theoretical and experimental spectra although the experimental spectra show subtle but significant differences.

  6. Embryotoxic effects of benzo(. cap alpha. )pyrene, chrysene, and 7,12-dimethylbenz(. cap alpha. )anthracene in petroleum hydrocarbon mixtures in mallard ducks

    SciTech Connect

    Hoffman, D.J.; Gay, M.L.

    1981-05-01

    In the present study the effects of three polycyclic aromatic hydrocarbons identified in petroleum were examined on mallard (Anas platyrhynchos) embryo development. Addition of benzo(a)pyrene (BaP), chrysene, or 7,12-dimethylbenz(a)anthracene (DMBA) to a synthetic petroleum hydrocarbon mixture of known composition and relatively low embryotoxicity resulted in embryotoxicity that was enhanced or equal to that of crude oil when 10 ..mu../ was applied externally to eggs at 72 h of development. The order of ability to enhance embryotoxicity was DMBA > BaP > chrysene. The temporal pattern of embryonic death was similar to that reported after exposure to crude oil. Retarded growth was accompanied by teratogenicity. Gas chromatographic-mass spectral analysis of externally treated eggs showed the passage of aromatic hydrocarbons including chrysene through the shell and shell membranes to the developing embryos. These findings suggest that the presence of polycyclic aromatic hydrocarbons in petroleum, including BaP, chrysene, and DMBA, significantly enhances the overall embryotoxicity in avian species.

  7. The anharmonic quartic force field infrared spectra of five non-linear polycyclic aromatic hydrocarbons: Benz[a]anthracene, chrysene, phenanthrene, pyrene, and triphenylene.

    PubMed

    Mackie, Cameron J; Candian, Alessandra; Huang, Xinchuan; Maltseva, Elena; Petrignani, Annemieke; Oomens, Jos; Mattioda, Andrew L; Buma, Wybren Jan; Lee, Timothy J; Tielens, Alexander G G M

    2016-08-28

    The study of interstellar polycyclic aromatic hydrocarbons (PAHs) relies heavily on theoretically predicted infrared spectra. Most earlier studies use scaled harmonic frequencies for band positions and the double harmonic approximation for intensities. However, recent high-resolution gas-phase experimental spectroscopic studies have shown that the harmonic approximation is not sufficient to reproduce experimental results. In our previous work, we presented the anharmonic theoretical spectra of three linear PAHs, showing the importance of including anharmonicities into the theoretical calculations. In this paper, we continue this work by extending the study to include five non-linear PAHs (benz[a]anthracene, chrysene, phenanthrene, pyrene, and triphenylene), thereby allowing us to make a full assessment of how edge structure, symmetry, and size influence the effects of anharmonicities. The theoretical anharmonic spectra are compared to spectra obtained under matrix isolation low-temperature conditions, low-resolution, high-temperature gas-phase conditions, and high-resolution, low-temperature gas-phase conditions. Overall, excellent agreement is observed between the theoretical and experimental spectra although the experimental spectra show subtle but significant differences.

  8. Micronuclei in mouse skin cells following in vivo exposure to benzo(a)pyrene, 7,12-dimethylbenz(a)anthracene, chrysene, pyrene and urethane

    SciTech Connect

    Shuilin He ); Baker, R. )

    1991-01-01

    Detection of micronuclei (MN) in skin cells from HRA/Skh hairless mice treated with chemical or physical agents may prove informative in qualitative and quantitative studies of skin carcinogenesis. MN induction and cell survival were estimated in cytokinesis-blocked keratinocytes, cultured for 4 days in vitro, after a single topical dose of various organic compounds. Treatment with 7,12-dimethylbenz(a)anthracene (DMBA) resulted in maximal MN induction in cells removed from skin 12-24 hr after topical administration. Even in cells removed only 1 hr after DMBA treatment, a significant increase in MN was evident. However, to allow sufficient time for metabolic activation, a sampling time of 24 hr was adopted for all test substances. Dose-dependent increases in MN were observed with DMBA, benzo(a)pyrene, chrysene, and urethane. Increased numbers of micronucleated cells were detected at the lowest doses administered in the present study. Although reduced cell recovery occurred following exposure of mice to acetone, pyrene, and other chemicals, there was no evidence that cytotoxicity contributed to MN scored in keratinocytes. Moreover, the probable noncarcinogen, pyrene, failed to induce MN at doses from 2.5 {mu}g to 2.5 mg/mouse. These results show that it is possible to assess chemical exposure in skin by measuring cell survival and skin genotoxicity by measuring MN induction in cultured keratinocytes.

  9. The anharmonic quartic force field infrared spectra of five non-linear polycyclic aromatic hydrocarbons: Benz[a]anthracene, chrysene, phenanthrene, pyrene, and triphenylene.

    PubMed

    Mackie, Cameron J; Candian, Alessandra; Huang, Xinchuan; Maltseva, Elena; Petrignani, Annemieke; Oomens, Jos; Mattioda, Andrew L; Buma, Wybren Jan; Lee, Timothy J; Tielens, Alexander G G M

    2016-08-28

    The study of interstellar polycyclic aromatic hydrocarbons (PAHs) relies heavily on theoretically predicted infrared spectra. Most earlier studies use scaled harmonic frequencies for band positions and the double harmonic approximation for intensities. However, recent high-resolution gas-phase experimental spectroscopic studies have shown that the harmonic approximation is not sufficient to reproduce experimental results. In our previous work, we presented the anharmonic theoretical spectra of three linear PAHs, showing the importance of including anharmonicities into the theoretical calculations. In this paper, we continue this work by extending the study to include five non-linear PAHs (benz[a]anthracene, chrysene, phenanthrene, pyrene, and triphenylene), thereby allowing us to make a full assessment of how edge structure, symmetry, and size influence the effects of anharmonicities. The theoretical anharmonic spectra are compared to spectra obtained under matrix isolation low-temperature conditions, low-resolution, high-temperature gas-phase conditions, and high-resolution, low-temperature gas-phase conditions. Overall, excellent agreement is observed between the theoretical and experimental spectra although the experimental spectra show subtle but significant differences. PMID:27586928

  10. Eu3+/Sm3+ hybrids based with 8-hydroxybenz[de]anthracen-7-one organically modified mesoporous silica SBA-15/16

    NASA Astrophysics Data System (ADS)

    Gu, Yan-Jing; Yan, Bing

    2015-12-01

    A series of organic-inorganic hybrid materials were prepared by linking lanthanide (Eu3+, Sm3+) complexes to mesoporous SBA-15/SBA-16 through 8-hydroxybenz[de]anthracen-7-one modified silane (HBA-Si) as linker. The physical characterizations of these hybrids revealed that they all have high surface area, uniformity in mesostructure. The luminescence properties of these covalently bonded materials (denoted as Ln(HBA-SBA-15)3phen and Ln(HBA-SBA-16)3phen) were compared with ternary complexes (Ln(HBA)3phen) (Ln = Eu, Sm). Eu(HBA-SBA-15(16))3phen hybrids display better thermal stability, whose luminescent lifetimes and quantum efficiencies were matchable with those of Eu(HBA)3phen complex in spite of its much lower effective condensation of Eu3+ species. In addition, the luminescent performance of functionalized SBA-15 hybrids was more favorable than that of functionalized SBA-16 hybrids, revealing that SBA-15 was a better host material for lanthanide complex than mesoporous silica SBA-16.

  11. Chemoprevention of 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster cheek pouch carcinogenesis by a 5-lipoxygenase inhibitor, garcinol.

    PubMed

    Chen, Xin; Zhang, Xinyan; Lu, Ye; Shim, Joong-Youn; Sang, Shengmin; Sun, Zheng; Chen, Xiaoxin

    2012-01-01

    Our previous studies have shown that aberrant arachidonic acid metabolism, especially the 5-lipoxygenase (5-Lox) pathway, is involved in oral carcinogenesis and can be targeted for cancer prevention. To develop potent topical agents for oral cancer chemoprevention, 5 known 5-Lox inhibitors from dietary and synthetic sources (Zileuton, ABT-761, licofelone, curcumin, and garcinol) were evaluated in silico for their potential efficacy. Garcinol, a polyisoprenylated benzophenone from the fruit rind of Garcinia spp., was found to be a promising agent based on the calculation of a theoretical activity index. Computer modeling showed that garcinol well fit the active site of 5-Lox, and potentially inhibited enzyme activity through interactions between the phenolic hydroxyl groups and the non-heme catalytic iron. In a short-term study on 7,12-dimethylbenz[a]anthracene (DMBA)-treated hamster cheek pouch, topical garcinol suppressed leukotriene B4 (LTB4) biosynthesis and inhibited inflammation and cell proliferation in the oral epithelium. In a long-term carcinogenesis study, topical garcinol significantly reduced the size of visible tumors, the number of cancer lesions, cell proliferation, and LTB4 biosynthesis. These results demonstrated that topical application of a 5-Lox inhibitor, garcinol, had chemopreventive effect on DMBA-induced hamster cheek pouch carcinogenesis. PMID:23137051

  12. Estrogen deprivation and excess energy supply accelerate 7,12-dimethylbenz(a)anthracene-induced mammary tumor growth in C3H/HeN mice

    PubMed Central

    Kim, Jin; Lee, Yoon Hee; Park, Jung Han Yoon

    2015-01-01

    BACKGROUND/OBJECTIVES Obesity is a risk factor of breast cancer in postmenopausal women. Estrogen deprivation has been suggested to cause alteration of lipid metabolism thereby creating a cellular microenvironment favoring tumor growth. The aim of this study is to investigate the effects of estrogen depletion in combination with excess energy supply on breast tumor development. MATERIALS/METHODS Ovariectomized (OVX) or sham-operated C3H/HeN mice at 4 wks were provided with either a normal diet or a high-fat diet (HD) for 16 weeks. Breast tumors were induced by administration of 7,12-dimethylbenz(a)anthracene once a week for six consecutive weeks. RESULTS Study results showed higher serum concentrations of free fatty acids and insulin in the OVX+HD group compared to other groups. The average tumor volume was significantly larger in OVX+HD animals than in other groups. Expressions of mammary tumor insulin receptor and mammalian target of rapamycin proteins as well as the ratio of pAKT/AKT were significantly increased, while pAMPK/AMPK was decreased in OVX+HD animals compared to the sham-operated groups. Higher relative expression of liver fatty acid synthase mRNA was observed in OVX+HD mice compared with other groups. CONCLUSIONS These results suggest that excess energy supply affects the accelerated mammary tumor growth in estrogen deprived mice. PMID:26634052

  13. Chemopreventive and Antilipidperoxidative Efficacy of Piper longum (Linn.) on 7,12-dimethylbenz (a) anthracene (DMBA) Induced Hamster Buccal Pouch Carcinogenesis

    NASA Astrophysics Data System (ADS)

    Senthil, Namasivayam; Manoharan, Shanmugam; Balakrishnan, Subramanian; Rajmani Ramachandran, Cinnamanoor; Muralinaidu, Radhakrishnan

    Aim of the present study was to find out the chemopreventive efficacy of Piper longum, a plant having diverse medicinal properties, in 7,12-dimethyl benz (a) anthracene (DMBA) induced oral carcinogenesis. The mechanistic pathway for its chemopreventive potential was analysed by measuring lipid peroxidation and antioxidants status in DMBA induced oral cancer. DMBA painting in hamster buccal pouch three times per week for 14 weeks resulted in well developed, well differentiated squamous cell carcinoma. Elevated lipid peroxidation and decline in antioxidants were noticed in tumor bearing hamsters as compared to control animals. Oral administration of ethanolic extract of Piper longum dried fruits (PLEFet) on alternate days to DMBA painting significantly prevented the tumor incidence, volume and burden and restored the status of lipid peroxidation and antioxidants in DMBA painted hamsters. Our results indicate that the dried fruits of P. longum has suppressing effects on cell proliferation, which is probably due to its antilipid peroxidative and antioxidative potential during DMBA induced oral carcinogenesis.

  14. The effect of diet and exercise on incidence of 7,12 dimethylbenz(a)anthracene-induced mammary tumors in virgin BALB/c mice

    SciTech Connect

    White, M.T.; Lane, H.W.; Teer, P.; Keith, R.E.; Strahan, S. NASA, Houston, TX )

    1991-03-15

    The effects of rotating-drum treadmill exercise and diet on 7,12 dimethylbenz(a)anthracene (DMBA)-induced mammary tumors were investigated in virgin female BALB/c mice. The animals were fed one of three diets: AIN 76 (SD), high-fat diet (HFD), or a restricted calorie diet (RCD). All diets were begun at 6 weeks of age and fed ad libitum except for the restricted diet which was fed at 70% of the SD. At 8 weeks of age all animals received the first of 6 consecutive DMBA doses via gastric tube. Each diet had an exercise and no exercise subgroup. Exercise began at 10 wks of age (6 m/min for 60 min, 5 d/wk) and continued throughout the 9.5 mo. study. Exercise reduced feed consumption in SD and HFD groups. Body weight was similar in all groups with HFDEx having the lowest body wt. Calorie restriction had no effect on body wt. but reduced mammary tumor incidence in the SD groups; however, exercise did affect mammary tumor incidence in the other groups as follows: RCD = 28%, RCDEx = 13%; HFD = 31%, HFDEx = 19%. Caloric consumption appeared to be related to mammary tumor incidence rather than body wt. or dietary fat.

  15. Modulating Effect of Enicostemma littorale on the Expression Pattern of Apoptotic, Cell Proliferative, Inflammatory and Angiogenic Markers During 7, 12-Dimethylbenz (a) Anthracene Induced Hamster Buccal Pouch Carcinogenesis.

    PubMed

    Manoharan, Shanmugam; Rajasekaran, Duraisamy; Prabhakar, Murugaraj Manoj; Karthikeyan, Sekar; Manimaran, Asokan

    2015-01-01

    Enicostemma littorale leaves are traditionally used for the treatment of several diseases, including inflammation and cancer. This study has taken effort to explore the antitumor initiating potential of E. littorale leaves (ElELet) by analyzing the expression pattern of apoptotic (p53, Bcl-2 and Bcl-2 associated X-protein), cell-proliferative (cyclin D1 and proliferating cell nuclear antigen), angiogenic (vascular endothelial growth factor), invasive (matrix metalloproteinase-2 and 9), and inflammatory (NF-κB and cyclooxygenase-2) markers during 7, 12-dimethylbenz (a) anthracene (DMBA) induced hamster buccal pouch carcinogenesis. Oral tumors were induced in the buccal pouches of hamsters using the potent site and organ specific carcinogen, DMBA. DMBA application 3 times a week for 14 weeks resulted in tumor formation in the buccal pouches. Hundred percent tumor formations with dysregulation in the expression pattern of apoptotic, cell proliferative, inflammatory, angiogenic, and invasive markers were observed in the buccal pouches of hamsters treated with DMBA alone. ElELet at a dose of 250 mg/kg body weight orally to DMBA treated hamsters significantly prevented the tumor formation as well as corrected the abnormalities in the expression pattern of above mentioned molecular markers. ElELet thus modulated the expression pattern of all the above mentioned molecular markers in favor of the suppression of cell proliferation occurring in DMBA induced hamster buccal pouch carcinogenesis. PMID:26862274

  16. Modulation of ultraviolet light-, ethyl methanesulfonate-, and 7,12-dimethylbenz(A)anthracene-induced unscheduled DNA synthesis by retinol and retinoic acid in the primary rat hepatocyte

    SciTech Connect

    Budroe, J.D.; Shaddock, J.G.; Casciano, D.A.

    1987-01-01

    The effects of retinol and retinoic acid on unscheduled DNA synthesis (UDS) in primary Sprague-Dawley rat hepatocytes were studied in the presence and absence of know chemical and physical mutagens. Neither retinol or retinoic acid caused a significant increase in UDS over solvent control at concentrations ranging from 1 ..mu..M to 50 ..mu..M. Retinol and retinoic acid did not significantly affect 200..mu..g/mL ethyl methanesulfonate (EMS)- or 32 J/m/sup 2/ ultraviolet light (UV)-induced UDS at concentrations ranging from 1..mu..M to 50 ..mu..M. In contrast, retinol and retinoic acid significantly inhibited 2.5 ..mu..g/mL and 5.0 ..mu..g/mL 7,12-dimethyl-benz(a)-anthracene(DMBA)-induced UDS at concentrations of 1..mu..M or greater. Retinol-and retinoic acid-induced hepatocytotoxicity was studied in vitro using lactate dehydrogenase (LDH) release as an indicator of cytoxicity. Neither retinol nor retinoic acid caused significant increases in LDH release over solvent control 3 hours after treatment, whereas retinol caused a biologically significant increase in LDH release 24 hours posttreatment at concentrations of 50 ..mu..M and 100 ..mu..M. These data suggest that nontoxic concentrations of retinol and retinoic acid do not inhibit the DNA excision repair process but apparently affect the effective DNA adduct load due to the ultimate species of DMBA metabolite responsible for hepatocellular DNA damage.

  17. Effects of 7,12-dimethylbenz[a]anthracene on immune function and mixed-function oxygenase activity in the European starling

    SciTech Connect

    Trust, K.A.; Hooper, M.J. . Inst. of Wildlife and Environmental Toxicology); Fairbrother, A. . Environmental Research Lab.)

    1994-05-01

    Immune function and hepatic MFO activity were examined in adult and nestling starlings administered a synthetic PAH, 7,12-dimethylbenz[a]anthracene (DMBA). Methods used to examine the starling immune system included immunopathology, macrophage phagocytosis, lymphocyte blastogenesis to concanavalin A, and hemagglutination of sheep erythrocytes (SRBC). Concomitant investigations of MFO activity were conducted in starlings exposed to DMBA. Ethoxyresorufin O-dealkylase (EROD) and pentoxyresorufin O-depentylase (PROD) were used as indicators of hepatic MFO activity. Changes in MFO activity were compared to chemically altered immune responses following DMBA exposure. Subcutaneous exposure of adult starlings to 125 mg/kg DMBA resulted in suppression of lymphocyte blastogenesis and antibody production to SRBC. EROD and PROD activity were increased 2.8- and 3.4-fold, respectively. Lymphocyte blastogenesis was impaired in adult starlings orally exposed to 125 mg/kg DMBA. The immune system of nestling starlings exposed orally to 100 mg/kg DMBA was altered, as evidenced by decreased phagocytic ability of macrophages and inhibition of lymphocyte blastogenesis. Oral exposure to DMBA did not induce MFO activity in starlings of either age class. Effects of DMBA on immune function and MFO activity in starlings varied with the age of birds and route and length of chemical exposure.

  18. Paternal selenium deficiency but not supplementation during preconception alters mammary gland development and 7,12-dimethylbenz[a]anthracene-induced mammary carcinogenesis in female rat offspring.

    PubMed

    Guido, Luiza N; Fontelles, Camile C; Rosim, Mariana P; Pires, Vanessa C; Cozzolino, Silvia M F; Castro, Inar A; Bolaños-Jiménez, Francisco; Barbisan, Luis F; Ong, Thomas P

    2016-10-15

    Breast cancer is a global public health problem and accumulating evidence indicates early-life exposures as relevant factors in the disease risk determination. Recent studies have shown that paternal nutrition can influence offspring health including breast cancer risk. Selenium is a micronutrient with essential role in central aspects of embryogenesis, male fertility and cancer and that has been extensively studied as a chemopreventive agent in several breast cancer experimental models. Thus, we designed an animal study to evaluate whether paternal selenium deficiency or supplementation during preconception could affect the female offspring mammary gland development and breast cancer susceptibility. Male Sprague-Dawley rats were fed AIN93-G diet containing 0.15 ppm (control diet), 0.05 ppm (deficient diet) or 1 ppm (supplemented diet) of selenium for 9 weeks and mated with control female rats. Mammary carcinogenesis was induced with 7,12-dimethylbenz[a]anthracene (DMBA) in their female offspring. Paternal selenium deficiency increased the number of terminal end buds, epithelial elongation and cell proliferation in the mammary gland of the female rat offspring and these effects were associated with higher susceptibility to DMBA-induced mammary tumors (increased incidence and higher grade tumors). On the other hand, paternal selenium supplementation did not influence any of these parameters. These results highlight the importance of father's nutrition including selenium status as a relevant factor affecting daughter's breast cancer risk and paternal preconception as a potential developmental stage to start disease preventive strategies. PMID:27270969

  19. Effect of gamma-linolenic acid and dihomo-gamma-linolenic acid 7,12-dimethylbenz(a)anthracene-induced mammary tumorigenesis

    SciTech Connect

    Ramchurren, N.; Karmali, R.A. )

    1991-03-15

    Gamma-linolenic acid (GLA) and its sequential metabolite, dihomogamma-linolenic acid (DHLA) have been reported to influence growth of neoplastic cells in culture. The pure forms of these fatty acids have not been tested in vivo. The authors have studied the effect of GLA and DHLA on mammary tumors induced by 7,12-dimethylbenz(a) anthracene (DMBA) (7.5 mg/rat) in female Sprague-Dawley rats. Rats received either 0.15 g of GLA or DHLA or corn oil (CO) orally, twice weekly for a period of 12 weeks. All three groups of rats were maintained on a diet containing 5% (w/w) corn oil as fat. Tumor incidence and multiplicity were recorded. The group receiving 0.15 g Co had higher tumor yields than those receiving GLA or DHLA. At the end of the experiment, tumor incidence was the lowest in the group receiving DHLA. Tumor multiplicity was consistently lowest with GLA. Fatty acid composition of mammary tissue and liver reflected that of fatty acid treatment. These results suggest that oral administration of GLA or DHLA retards the development of DMBA-induced mammary tumors in rats receiving a diet containing 5% (w/w) corn oil.

  20. Comparison of ovariectomy and retinyl acetate on the growth of established 7,12-dimethylbenz(a)anthracene-induced mammary tumors in the rat

    SciTech Connect

    Gandlihon, P.; Melancon, R.; Djiane, J.; Kelly, P.A.

    1982-08-01

    Prolonged exposure to retinyl acetate (RA) in the diet inhibits the development of 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary cancers in rats. The effectiveness of RA was examined when given 6 months after the administration of DMBA. Non-inbred female Sprague-Dawley rats with DMBA-induced mammary tumors were divided into 3 groups and treated for 4 weeks as follows: Group 1 served as controls, group 2 was ovariectomized, and group 3 received 328 mg RA/kg diet. Ovariectomy (OVX) markedly reduced both the number and size of the tumors. RA administration failed to induce any significant regression in tumor number but significantly retarded tumor growth when compared to tumor growth in group 1 controls. The levels of estradiol, progestin, and prolactin (PRL) receptors were significantly reduced after OVX, whereas only the levels of PRL receptors declined significantly after RA administration. Circulating progesterone concentrations were not affected in the RA-treated group but the plasma PRL level was significantly increased. The present studies show that if treatment with RA is delayed until 6 months after carcinogen administration, the protective effect of RA can still be observed although its effectiveness is less dramatic than when it is administered earlier.

  1. Combination between Taxol-Encapsulated Liposomes and Eruca sativa Seed Extract Suppresses Mammary Tumors in Female Rats Induced by 7,12 Dimethylbenz(α)anthracene.

    PubMed

    Shaban, Nadia; Abdel-Rahman, Salah; Haggag, Amany; Awad, Doaa; Bassiouny, Ahmad; Talaat, Iman

    2016-01-01

    Taxol (paclitaxel) is a powerful anti-cancer drug widely used against several types of malignant tumors. Because Taxol may exert several side effects, a variety of formulations have been developed. One of these features liposomes, regarded as one of the most promising drug carriers, biocompatible and best able to reduce drug toxicity without changing efficacy against tumor cells. Eruca sativa seed extract (SE) is considered a promising natural product from cruciferous vegetables against breast cancer, increasing chemotherapeutic and eliminating harmful side effects. The effects of Taxol-encapsulated liposomes (T) alone and in combination between Eruca sativa seed extract on nuclear factor kappa B (NF-κB), cyclooxygenase-2 (COX-2) and B-cell lymphoma-2 (Bcl-2) gene expression levels were investigated in rat mammary gland carcinogenesis induced by 7,12 dimethylbenz(α) anthracene (DMBA) using qRT-PCR. The results showed that DMBA increased NF-κB, COX-2 and Bcl-2 gene expression levels and lipid peroxidation (LP), while decreasing glutathione-S-transferase (GST) and superoxide dismutase (SOD) activities and total antioxidant concentration (TAC) compared to the control group. T and T-SE treatment reduced NF-κB, COX-2 and Bcl-2 gene expression levels and LP. Hence, T and T-SE treatment appeared to reduce inflammation and cell proliferation, while increasing apoptosis, GST and SOD activities and TAC. PMID:26838195

  2. Cytotoxic effects and metabolism of benzo(a)pyrene and 7,12-dimethylbenz(a)anthracene in duodenal and ileal epithelial cell cultures. [Rats

    SciTech Connect

    Quaroni, A.; Isselbacher, K.J.

    1981-12-01

    Two epithelial cell lines have been established from the duodenum (IEC-17) and the ileum (IEC-18) of outbred germfree Crl:CD(SD)GN rats. They have a very similar morphology and ultrastruture, a normal rat diploid karyotype, comparable growth rates, and a similar set of surface antigens as detected with monoclonal antibodies specific for intestinal epithelial cell surface proteins in vivo. Both cell lines do not grow in soft agar and when injected into syngeneic animals do not form tumors. The toxic effects of benzo(a)pyrene (BP) and 7,12-dimethylbenz(a)anthracene (DMBA) were studied in these two cell lines. The IEC-18 cells were found to be much more sensitive to both chemicals than the IEC-17 cells. In paticular, at concentrations greater than 1 ..mu..g/ml, DMBA completely and irreversibly inhibited cell proliferaion in the IEC-18 cells, whereas it produced a less marked and reversible inhibition in the IEC-17 cells. The metabolism of BP and DMBA to water-soluble products was studied; BP was apparently metabolized at similar rates in the two cell lines, whereas a striking difference was observed with DMBA, which was metabolized at a rate 10-15 times greater in the IEC-18 cells than that in the IEC-17 cells. These results suggest that cultured cell lines derived from different portions of the intestinal tract have similar propertes in vitro, but they may have very different responses to chemical carcinogens.

  3. Modulation of ultraviolet light-, ethyl methanesulfonate-, and 7,12-dimethylbenz(a)anthracene-induced unscheduled DNA synthesis by retinol and retinoic acid in the primary rat hepatocyte

    SciTech Connect

    Budroe, J.D.; Shaddock, J.G.; Casciano, D.A.

    1987-01-01

    The effects of retinol and retinoic acid on unscheduled DNA synthesis (UDS) in primary Sprague-Dawley rat hepatocytes were studied in the presence and absence of known chemical and physical mutagens. Neither retinol nor retinoic acid caused a significant increase in UDS over solvent control at concentrations ranging from 1 microM to 50 microM. Retinol and retinoic acid did not significantly affect 200 micrograms/mL ethyl methanesulfonate(EMS)- or 32 J/m2 ultraviolet light(UV)-induced UDS at concentrations ranging from 1 microM to 50 microM. In contrast, retinol and retinoic acid significantly inhibited 2.5 micrograms/mL and 5.0 micrograms/mL 7,12-dimethyl-benz(a)anthracene(DMBA)-induced UDS at concentrations of 1 microM or greater. Retinol- and retinoic acid-induced hepatocytotoxicity was studied in vitro using lactate dehydrogenase (LDH) release as an indicator of cytoxicity. Neither retinol nor retinoic acid caused significant increases in LDH release over solvent control 3 hours after treatment, whereas retinol caused a biologically significant increase in LDH release 24 hours posttreatment at concentrations of 50 microM and 100 microM. These data suggest that nontoxic concentrations of retinol and retinoic acid do not inhibit the DNA excision repair process but apparently affect the effective DNA adduct load due to the ultimate species of DMBA metabolite responsible for hepatocellular DNA damage.

  4. Induction of mammary tumors in virgin female BALB/c mice by single low doses of 7,12-dimethylbenz(a)anthracene

    SciTech Connect

    Ethier, S.P.; Ullrich, R.L.

    1982-11-01

    The induction of mammary tumors in virgin female inbred BALB/c mice after administration of 7,12-dimethylbenz(a)anthracene (DMBA) over a wide range of doses was studied. Mice were exposed at 12 weeks of age to single or multiple doses of DMBA ranging from 0.0025 to 12.0 mg by gastric intubation and were checked regularly for mammary tumors. The experiment was terminated when the mice were 800 days of age. In the dose range of 0.0025-0.125 mg DMBA, the incidence of mammary tumors was dose-dependent. At higher doses, the mammary tumor incidence became less dose-dependent and was nearly independent of doses above the 0.25-mg level. Analysis of the data for the rate of appearance of mammary tumor with age of the animals and for the age at death of non-mammary tumor-bearing animals indicated that in the low dose range induction of mammary tumors was the predominant effect of DMBA exposure, whereas at moderate to high doses the toxic and carcinogenic effects of DMBA on other tissues significantly influenced the final incidence of mammary tumors. Greater than 90% of the tumors that resulted from administration of low doses of DMBA were adenocarcinomas. In contrast, adenocarcinomas and adenoacanthomas were found in approximately equal proportions following administration of high doses of DMBA.

  5. Carcinogenicity and DNA binding of benzo(a)pyrene and 7,12-dimethylbenz(a)anthracene in rainbow trout by controlled laboratory exposure

    SciTech Connect

    Fong, A.T.; Hendricks, J.D.; Bailey, G.S. )

    1988-09-01

    Polycyclic aromatic hydrocarbons (PAH) recently have been implicated as etiological agents responsible for observed neoplasia in some feral fish populations. However, establishing a direct causal relationship has not been possible in part because only a few PAH have been tested for carcinogenicity in fish models. The present studies were undertaken to characterize the carcinogenicity and DNA binding of benzo(a)pyrene (BP) and 7,12-dimethylbenz(a)anthracene (DMBA) in the rainbow trout by controlled laboratory exposure. Two parameters which may influence tumor response to PAH were examined, route of exposure and life stage at exposure. Although rainbow trout seldom inhibit polluted environments where fish tumor epizootics occur, this extensively studied fish species provides a useful model for examining the carcinogenic effects of environmental contamination because they have been shown to be highly sensitive to the carcinogenic effects of aflatoxin B{sub 1} and over 20 other carcinogens. The results of these studies show that the trout is sensitive to the carcinogenic effects of PAH at the embryo, fry, and juvenile life stages, and that tumor response and site of tumor formation depend on the particular PAH used, the dose of PAH, and the route of administration.

  6. Antineoplastic effect of iodine and iodide in dimethylbenz[a]anthracene-induced mammary tumors: association between lactoperoxidase and estrogen-adduct production.

    PubMed

    Soriano, Ofelia; Delgado, Guadalupe; Anguiano, Brenda; Petrosyan, Pavel; Molina-Servín, Edith D; Gonsebatt, Maria E; Aceves, Carmen

    2011-08-01

    Several groups, including ours, have reported that iodine exhibited antiproliferative and apoptotic effects in various cancer cells only if this element is supplemented as molecular iodine, or as iodide, to cells that are able to oxidize it with the enzyme thyroperoxidase. In this study, we analyzed the effect of various concentrations of iodine and/or iodide in the dimethylbenz[a]anthracene (DMBA) mammary cancer model in rats. The results show that 0.1% iodine or iodide increases the expression of peroxisome proliferator-activated receptor type γ (PPARγ), triggering caspase-mediated apoptosis pathways in damaged mammary tissue (DMBA-treated mammary gland) as well as in frank mammary tumors, but not in normal mammary gland. DMBA treatment induces the expression of lactoperoxidase, which participates in the antineoplastic effect of iodide and could be involved in the pro-neoplastic effect of estrogens, increasing the formation of DNA adducts. In conclusion, our results show that a supplement of 0.1% molecular iodine/potassium iodide (0.05/0.05%) exert antineoplastic effects, preventing estrogen-induced DNA adducts and inducing apoptosis through PPARγ/caspases in pre-cancer and cancerous cells. Since this iodine concentration does not modify the cytology (histology, apoptosis rate) or physiology (triiodothyronine and thyrotropin) of the thyroid gland, we propose that it be considered as an adjuvant treatment for premenopausal mammary cancer.

  7. Decreased expression of stem cell markers by simvastatin in 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast cancer.

    PubMed

    Rennó, André Lisboa; Alves-Júnior, Marcos José; Rocha, Rafael Malagoli; De Souza, Philipi Coutinho; de Souza, Valéria Barbosa; Jampietro, Juliano; Vassallo, José; Hyslop, Stephen; Anhê, Gabriel Forato; de Moraes Schenka, Natália Guimarães; Soares, Fernando Augusto; Schenka, André Almeida

    2015-04-01

    Simvastatin, a competitive inhibitor of HMG-CoA reductase widely used in the treatment and prevention of hyperlipidemia-related diseases, has recently been associated to in vitro anticancer stem cell (CSC) actions. However, these effects have not been confirmed in vivo. To assess in vivo anti-CSC effects of simvastatin, female Sprague-Dawley rats with 7,12-dimethyl-benz(a)anthracene (DMBA)-induced mammary cancer and control animals were treated for 14 days with either simvastatin (20 or 40 mg/kg/day) or soybean oil (N = 60). Tumors and normal breast tissues were removed for pathologic examination and immunodetection of CSC markers. At 40 mg/kg/day, simvastatin significantly reduced tumor growth and the expression of most CSC markers. The reduction in tumor growth (80%) could not be explained solely by the decrease in CSCs, since the latter accounted for less than 10% of the neoplasia (differentiated cancer cells were also affected). Stem cells in normal, nonneoplastic breast tissues were not affected by simvastatin. Simvastatin was also associated with a significant decrease in proliferative activity but no increase in cell death. In conclusion, this is the first study to confirm simvastatin anti-CSC actions in vivo, further demonstrating that this effect is specific for neoplastic cells, but not restricted to CSCs, and most likely due to inhibition of cell proliferation.

  8. Modulating Effect of Enicostemma littorale on the Expression Pattern of Apoptotic, Cell Proliferative, Inflammatory and Angiogenic Markers During 7, 12-Dimethylbenz (a) Anthracene Induced Hamster Buccal Pouch Carcinogenesis

    PubMed Central

    Manoharan, Shanmugam; Rajasekaran, Duraisamy; Prabhakar, Murugaraj Manoj; Karthikeyan, Sekar; Manimaran, Asokan

    2015-01-01

    Enicostemma littorale leaves are traditionally used for the treatment of several diseases, including inflammation and cancer. This study has taken effort to explore the antitumor initiating potential of E. littorale leaves (ElELet) by analyzing the expression pattern of apoptotic (p53, Bcl-2 and Bcl-2 associated X-protein), cell-proliferative (cyclin D1 and proliferating cell nuclear antigen), angiogenic (vascular endothelial growth factor), invasive (matrix metalloproteinase-2 and 9), and inflammatory (NF-κB and cyclooxygenase-2) markers during 7, 12-dimethylbenz (a) anthracene (DMBA) induced hamster buccal pouch carcinogenesis. Oral tumors were induced in the buccal pouches of hamsters using the potent site and organ specific carcinogen, DMBA. DMBA application 3 times a week for 14 weeks resulted in tumor formation in the buccal pouches. Hundred percent tumor formations with dysregulation in the expression pattern of apoptotic, cell proliferative, inflammatory, angiogenic, and invasive markers were observed in the buccal pouches of hamsters treated with DMBA alone. ElELet at a dose of 250 mg/kg body weight orally to DMBA treated hamsters significantly prevented the tumor formation as well as corrected the abnormalities in the expression pattern of above mentioned molecular markers. ElELet thus modulated the expression pattern of all the above mentioned molecular markers in favor of the suppression of cell proliferation occurring in DMBA induced hamster buccal pouch carcinogenesis. PMID:26862274

  9. Effects of morin on the pharmacokinetics of docetaxel in rats with 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary tumors.

    PubMed

    Yang, Si H; Lee, Joo H; Lee, Dae Y; Lee, Myung G; Lyuk, Koon C; Kim, So H

    2011-10-01

    Docetaxel is a P-glycoprotein (P-gp) substrate and metabolized via cytochrome P450 (CYP) 3A subfamily in rats. Morin is an inhibitor of both CYPs and P-gp. Hence, the effects of morin on the intravenous and oral pharmacokinetics of docetaxel were investigated using 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary tumor rats (DMBA rats) as an animal model of human breast cancer. Docetaxel was administered intravenously (4 mg/kg) and orally (20 mg/kg) without and with morin (15 mg/kg) in DMBA rats. After the intravenous administration of docetaxel in control and DMBA rats with and without morin, the values of non-renal clearance and area under the plasma concentration-time (AUC) for docetaxel were comparable. Morin did not increase AUC or the absolute oral bioavailability (F) for docetaxel after the oral administration of docetaxel in control and DMBA rats with and without morin. The inhibition of hepatic and intestinal metabolism of docetaxel by morin and/or DMBA and the effect of intestinal P-gp inhibition by morin on the pharmacokinetics of docetaxel did not seem to be considerable in DMBA-induced mammary tumor rats.

  10. Kinetic and spectrophotometric investigation of the diels-alder reaction between maleic anhydride derivatives and substituted anthracenes in the presence of gallium and aluminum chlorides

    SciTech Connect

    Kiselev, V.D.; Konovalov, A.I.; Shakirov, I.M.

    1986-10-01

    A comparison was made of the kinetic data for the normal Diels-Alder reaction of para-substituted N-arylmaleimides and substituted maleic anhydrides with meso-substituted anthracenes and of the reaction catalyzed by gallium and aluminum chlorides. The largely constant effects of gallium chloride (10/sup 4/) and aluminum chloride (10/sup 5/) in the acceleration of the reactions between the various pairs were demonstrated. The energies of charge transfer in the complexes between hexamethylbenzene and the dienophiles in the presence and absence of Lewis acids were determined by spectrophotometry. A significant decrease (to 1.2 eV) of the charge-transfer energy was found in the ..pi.., ..pi..-complexes and was attributed to the stabilization of the LUMO of the dienophile. From analysis of the obtained data it was concluded that the observed catalytic effect in the presence of Lewis acids can be explained by the approach of the frontier orbital levels and by a favorable change in the coefficients at the atomic orbitals responsible for the reaction.

  11. Oral artemisinin prevents and delays the development of 7,12-dimethylbenz[a]anthracene (DMBA)-induced breast cancer in the rat.

    PubMed

    Lai, Henry; Singh, Narendra P

    2006-01-01

    Artemisinin, a compound isolated from the sweet wormwood Artemisia annua L., has previously been shown to have selective toxicity towards cancer cells in vitro. In the present experiment, we studied the potential of artemisinin to prevent breast cancer development in rats treated with a single oral dose (50mg/kg) of 7,12-dimethylbenz[a]anthracene (DMBA), known to induce multiple breast tumors. Starting from the day immediately after DMBA treatment, one group of rats was provided with a powdered rat-chow containing 0.02% artemisinin, whereas a control group was provided with plain powdered food. For 40 weeks, both groups of rats were monitored for breast tumors. Oral artemisinin significantly delayed (P<.002) and in some animals prevented (57% of artemisinin-fed versus 96% of the controls developed tumors, P<.01) breast cancer development in the monitoring period. In addition, breast tumors in artemisinin-fed rats were significantly fewer (P<.002) and smaller in size (P<.05) when compared with controls. Since artemisinin is a relatively safe compound that causes no known side effects even at high oral doses, the present data indicate that artemisinin may be a potent cancer-chemoprevention agent. PMID:16356830

  12. Apoptosis induction by S-allylcysteine, a garlic constituent, during 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis.

    PubMed

    Balasenthil, S; Rao, K S; Nagini, S

    2002-09-01

    The apoptosis-inducing capacity of S-allylcysteine (SAC), a water-soluble garlic constituent, during 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch (HBP) carcinogenesis was investigated in male Syrian hamsters using DNA fragmentation and the apoptosis-associated proteins, tissue transglutaminase (tTG) and Bcl-2. Hamsters were divided into four groups of six animals each. Animals in group 1 were painted with a 0.5% solution of DMBA in liquid paraffin on the right buccal pouches three times a week for 14 weeks. Group 2 animals painted with DMBA as in group 1, in addition received 200 mg kg(-1) body weight SAC orally on days alternate to DMBA application. Group 3 animals received SAC as in group 2. Group 4 animals received neither DMBA nor SAC and served as the control. The experiment was terminated at the end of 14 weeks. Administration of SAC (200 mg kg(-1) body weight) to animals painted with DMBA inhibited DMBA-induced HBP carcinogenesis as revealed by the absence of neoplasms, induction of tTG and inhibition of Bcl-2 expression. The results of the present study suggest that SAC may exert its chemopreventive effect by inducing apoptosis. PMID:12125104

  13. The effect of gender, sexual maturation and xenobiotic treatment on the formation of hydroxymethyl metabolites from 7, 12-dimethylbenz[a]anthracene in rat liver microsomes.

    PubMed

    Boyle, S P; Craft, J A

    2000-09-30

    The effects of age, gender, strain, phenobarbital (PB) treatment and pituitary influence on the regioselective metabolism of 7, 12-dimethylbenz[a]anthracene to hydroxmethyl metabolites were investigated. Studies used hepatic microsomal membranes from immature and mature Long Evans (LE) rats and adult Hooded Lister (HL) animals. Hydroxymethyl metabolites were resolved by both normal and reverse phase HPLC with on-line diode array detection. The CYP isoform(s) responsible for oxidation at the 12 methyl position exhibited no gender or developmental regulation and the rate of formation was not altered following hypophysectomy. PB-treatment of adult rats caused a significant increase in the rate of formation of both male and female animals (29 and 41-fold, respectively) suggesting a major contribution from a PB-inducible isoform, such as CYP2B. The rate of formation of 7OHMe12MBA exhibited no gender dependency in immature animals but was 2-fold greater than that observed for 12OHMe7MBA suggesting that steric hindrance resulting from the adjacent 1,2 benzyl ring favours substrate oxidation at the 7-methyl position. Male predominant formation of 7OHMe12MBA was apparent following sexual maturation of the LE rats and was significantly reduced upon hypophysectomy suggesting the involvement of a male-specific GH dependent isoform e.g. CYP2C11. PMID:11033228

  14. Influence of mode of exposure and the presence of a tubiculous polychaete on the fate of benz(a)anthracene in the benthos

    SciTech Connect

    McElroy, A.E.; Farrington, J.W.; Teal, J.M. )

    1990-11-01

    The distribution and metabolism of ({sup 14}C-12)benz(a)-anthracene (BA) was followed in benthic microcosms in the presence and absence of the polychaete Nereis virens for periods of 4-25 days to simultaneously assess the effects of mode of introduction and the presence of large burrowing organisms on the fate of polycyclic aromatic hydrocarbons (PAH) and their metabolites in the benthos. Radiolabeled BA was added to the chambers in three ways: already sorbed to the entire sediment reservoir, directly into the water column, or incorporated into food for the worms. BA added to the water column was more available for uptake and metabolism by worms and microbial mineralization to CO{sub 2} than BA previously sorbed to the entire sediment reservoir. In experiments with the sediment reservoir uniformly labeled with BA, worms increased flux of BA from the sediment, and with time, their presence led to increased rates of microbial mineralization of BA to CO{sub 2}. Dietary BA was most rapidly metabolized by Nereis.

  15. Enhanced cytostatic effectiveness of aniline mustard against 7,12-dimethylbenz[a]anthracene-induced rat mammary tumors during regression in response to ovariectomy.

    PubMed

    Benckhuysen, C; Ter Hart, H G; Van Dijk, P J

    1981-01-01

    Sprague-Dawley rats bearing 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary tumors were treated with either of two aromatic alkylating agents, aniline mustard or melphalan, alone or combined with ovariectomy. Both drugs were applied once a week for 8 weeks. Eight-four percent of the tumors responded to ovariectomy, 38% regressing completely and 46% regressing partially. Aniline mustard, though virtually ineffective as a single agent, appeared synergistic with ovariectomy: a 100% regression rate (72% complete, 28% partial) was observed for this combination. Treatment with melphalan was as effective as ovariectomy, but the combination of melphalan with ovariectomy was no more effective than either treatment alone. The end product of aniline mustard metabolism, p-hydroxyaniline mustard O-glucuronide, may be more extensively activated by beta-glucuronidase in hormonally regressing than in growing or stationary tumors. Intratumoral levels of beta-glucoronidase occurring in DMBA-induced tumors 4 days after ovariectomy were found to be similar to those in the aniline mustard-sensitive mouse plasma cell tumor ADJ/PC6. It remains to be more extensively studied whether an effect of endocrine treatment on tumor beta-glucuronidase levels, and possibly on intracellular distribution of enzyme, could be used therapeutically. An effectively scheduled cytostatic treatment (with a drug conjugate such as that formed metabolically from aniline mustard) in conjunction with ovariectomy might be effective in the treatment of hormone-responsive breast cancer.

  16. Theoretical study on exciton recurrence motion in anthracene dimer using the Ab initio MO-CI based quantum master equation approach.

    PubMed

    Kishi, Ryohei; Nakano, Masayoshi; Minami, Takuya; Fukui, Hitoshi; Nagai, Hiroshi; Yoneda, Kyohei; Takahashi, Hideaki

    2009-05-01

    We apply the ab initio molecular orbital (MO)-configuration interaction (CI) based quantum master equation (MOQME) method to the investigation of ultrafast exciton dynamics in an anthracene dimer modeled after anthracenophane, which is experimentally found to exhibit an oscillatory signal of fluorescence anisotropy decay. Two low-lying near-degenerate one-photon allowed excited states with a slight energy difference (42 cm(-1)) are obtained at the CIS/6-31G** level of approximation using full valence pi-orbitals. The time evolution of reduced exciton density matrices is performed by numerically solving the quantum master equation. After the creation of a superposition state of these near-degenerate states by irradiating a near-resonant laser field, we observe two kinds of oscillatory behaviors of polarizations: field-induced polarizations with faster periods, and amplitude oscillations of x- and z-polarizations, P(x) and P(z), with a slower period, in which the amplitudes of P(x) and P(z) attain maximum alternately. The latter behavior turns out to be associated with an oscillatory exciton motion between the two monomers, i.e., exciton recurrence motion, using the dynamic exciton expression based on the polarization density. From the analysis of contribution to the exciton distributions, such exciton recurrence motion is found to be characterized by both the difference in eigenfrequencies between the two near-degenerate states excited by the laser field and the relative phases among the frontier MOs primarily contributing to the near-degenerate states.

  17. Chronic unpredictable stress (CUS) enhances the carcinogenic potential of 7,12-dimethylbenz(a)anthracene (DMBA) and accelerates the onset of tumor development in Swiss albino mice.

    PubMed

    Suhail, Nida; Bilal, Nayeem; Hasan, Shirin; Ahmad, Ausaf; Ashraf, Ghulam Md; Banu, Naheed

    2015-11-01

    Social stressors evolving from individual and population interactions produce stress reactions in many organisms (including humans), influencing homeostasis, altering the activity of the immunological system, and thus leading to various pathological states including cancer and their progression. The present study sought to validate the effectiveness of chronic unpredictable stress (CUS) in cancer promotion and to assess oxidative stress outcomes in terms of various in vivo biochemical parameters, oxidative stress markers, DNA damage, and the development of skin tumors in Swiss albino mice. Animals were randomized into different groups based on their exposure to CUS alone, 7,12-dimethylbenz(a)anthracene (DMBA) alone (topical), and DMBA-12-O-tetradecanoylphorbol-13-acetate (TPA) (topical) and exposure to CUS prior to DMBA or DMBA-TPA treatments and sacrificed after 16 weeks of treatment. Prior exposure to CUS significantly increased the pro-oxidant effect of carcinogen, depicted by compromised levels of antioxidants in the circulation and skin, accompanied by enhanced lipid peroxidation, plasma corticosterone, and marker enzymes as compared to DMBA-alone or DMBA-TPA treatments. DNA damage results corroborated the above biochemical outcomes. Also, the development of skin tumors (in terms of their incidence, tumor yield, and tumor burden) in mice in the presence and absence of stress further strongly supported our above biochemical measurements. CUS may work as a promoter of carcinogenesis by enhancing the pro-oxidant potential of carcinogens. Further studies may be aimed at the development of interventions for disease prevention by identifying the relations between psychological factors and DNA damage.

  18. Chemopreventive effect of selenium-enriched Japanese radish sprout against breast cancer induced by 7,12-dimethylbenz[a]anthracene in rats.

    PubMed

    Yamanoshita, Osamu; Ichihara, Shu; Hama, Hidetoshi; Ichihara, Gaku; Chiba, Momoko; Kamijima, Michihiro; Takeda, Iwao; Nakajima, Tamie

    2007-06-01

    Breast cancer is one of the major cancers in women, and dietary intake must be controlled to prevent it. Selenium (Se), especially Se compound in vegetables, is thought to be a promising chemopreventive dietary ingredient for preventing breast cancer. In this study, we developed Se-enriched Japanese radish sprout using a special Se-additional fertilizer, and identified the Se chemical forms. The newly developed Se-enriched sprout is produced within a week by the tank forming method, and the major chemical form was identified as Se-methylselenocysteine (MeSeCys) (80%). Then, the chemopreventive effects of the Se-enriched sprout were investigated using Sprague-Dawley female rats with mammary cancer, induced by a single oral dose of 10 mg or 14 mg of 7, 12-dimethylbenz[a]anthracene (DMBA). Mammary tumors were found in 11, 16 and 2 rats treated with DMBA and thereafter fed the basal (n = 34), sprout-added basal (n = 30) and Se-enriched sprout-added test diets (n = 30), respectively. The incidence of mammary tumors was significantly lower in the Se-enriched sprout-added test diet group (7%) than in the basal diet group (32%) or sprout-added basal diet group (53%). In contrast, no significant difference was detected in the numbers and incidence of the tumor between the basal diet group and Se-enriched sprout-added test diet group before DMBA-dosing. These results suggest that the diet supplement of Se-enriched sprout after DMBA-dosing provides a significant chemoprevention against chemical-induced mammary cancer. Thus, Se-enriched sprout may be a useful dietary ingredient for preventing breast cancer.

  19. Zyflamend reduces LTB4 formation and prevents oral carcinogenesis in a 7,12-dimethylbenz[alpha]anthracene (DMBA)-induced hamster cheek pouch model.

    PubMed

    Yang, Peiying; Sun, Zheng; Chan, Diana; Cartwright, Carrie A; Vijjeswarapu, Mary; Ding, Jibin; Chen, Xiaoxin; Newman, Robert A

    2008-11-01

    Aberrant arachidonic acid metabolism, especially altered cyclooxygenase and 5-lipoxygenase (LOX) activities, has been associated with chronic inflammation as well as carcinogenesis in human oral cavity tissues. Here, we examined the effect of Zyflamend, a product containing 10 concentrated herbal extracts, on development of 7,12-dimethylbenz[alpha]anthracene (DMBA)-induced inflammation and oral squamous cell carcinoma (SCC). A hamster cheek pouch model was used in which 0.5% DMBA was applied topically onto the left cheek pouch of male Syrian golden hamsters either three times per week for 3 weeks (short term) or 6 weeks (long term). Zyflamend was then applied topically at one of three different doses (25, 50 and 100 microl) onto the left cheek pouch three times for 1 week (short-term study) or chronically for 18 weeks. Zyflamend significantly reduced infiltration of inflammatory cells, incidence of hyperplasia and dysplastic lesions, bromodeoxyuridine-labeling index as well as number of SCC in a concentration-dependent manner. Application of Zyflamend (100 microl) reduced formation of leukotriene B(4) (LTB(4)) by 50% compared with DMBA-treated tissues. The reduction of LTB(4) was concentration dependent. The effect of Zyflamend on inhibition of LTB(4) formation was further confirmed with in vitro cell-based assay. Adding LTB(4) to RBL-1 cells, a rat leukemia cell line expressing high levels of 5-LOX and LTA(4) hydrolase, partially blocked antiproliferative effect of Zyflamend. This study demonstrates that Zyflamend inhibited LTB(4) formation and modulated adverse histopathological changes in the DMBA-induced hamster cheek pouch model. The study suggests that Zyflamend might prevent oral carcinogenesis at the post-initiation stage. PMID:18687669

  20. 9D nonadiabatic quantum dynamics through a four-state conical intersection: Investigating the homolysis of the O-O bond in anthracene-9,10-endoperoxide

    NASA Astrophysics Data System (ADS)

    Assmann, Mariana; Worth, Graham A.; González, Leticia

    2012-12-01

    The excited state dynamics of anthracene-9,10-endoperoxide is investigated using quantum wavepacket dynamics. APO is an aromatic endoperoxide which, upon excitation to S1, shows a cleavage of the oxygen-oxygen bond, leading to rearrangement products. It was shown that the dynamics of the O-O cleavage is modulated by a four-state degeneracy [D. Mollenhauer, I. Corral, and L. González, J. Phys. Chem. Lett. 1, 1036 (2010)], 10.1021/jz100196q. The most important mode to describe the O-O cleavage is the opening of the O-O bond. Excitation to higher excited states Sn (n ⩾ 2) leads to the release of singlet molecular oxygen. For this release, the twist of the oxygen atoms around the molecular axis is an important mode. These two degrees of freedom were employed to calculate two-dimensional potential energy surfaces for the four singlet states which become degenerate. Further modes were included in terms of harmonic oscillators. Using the multiconfigurational time-dependent Hartree method, quantum dynamic simulations were performed in up to nine degrees of freedom. Moreover, the nine branching space vectors, which prove the degeneracy to be a four-state conical intersection (4CI), were calculated and included in the wavepacket propagations. The resulting dynamics show that the 4CI is reached very fast (in less than 30 fs after excitation) and the wavepacket distributes over all states. The degree of distribution into the states is very much dependent on which modes are included in the simulation.

  1. Uptake and phytotoxicity of anthracene and benzo[k]fluoranthene applied to the leaves of celery plants (Apium graveolens var. secalinum L.).

    PubMed

    Wieczorek, Jolanta; Sienkiewicz, Stanisław; Pietrzak, Monika; Wieczorek, Zbigniew

    2015-05-01

    The above-ground parts of celery plants were exposed to two polycyclic aromatic hydrocarbons (PAHs): 3-ring anthracene (ANT) and 5-ring benzo[k]fluoranthene (BkF), and the combination of ANT and BkF. After 43 days of exposure (overall dose of 1325µg/plant), celery plants retained only 1.4% of the total dose of ANT and 17.5% of the total dose of BkF. After exposure to a combination of ANT and BkF (1325µg of each compound per plant), the average ANT concentrations were more than twofold higher in/on leaf blades, whereas BkF levels were insignificantly higher. Under natural photoperiod conditions equivalent to a normal day, the combined application of ANT and BkF to the above-ground parts of celery plants slowed down physicochemical transformations of ANT. A similar effect was observed when PAHs were applied to glass surfaces. The combination of both PAHs probably led to stacking interactions, which decreased volatilization, in particular of ANT. Phytotoxicity of ANT and BkF could not be unambiguously established based on the results of this study. In all analyzed treatments, the chlorophyll content of leaf blades remained unchanged. Foliar application of ANT reduced ascorbic acid levels in all analyzed plant parts and increased the total acidity of celery leaves. In all experimental treatments, the total phenolic content of leaves increased up to 15%. Interestingly, ANT and BkF did not produce cumulative effects when applied in combination (when total PAH concentrations per plant were twofold higher). PMID:25666733

  2. Impact of obesity on 7,12-dimethylbenz[a]anthracene-induced altered ovarian connexin gap junction proteins in female mice

    SciTech Connect

    Ganesan, Shanthi Nteeba, Jackson Keating, Aileen F.

    2015-01-01

    The ovarian gap junction proteins alpha 4 (GJA4 or connexin 37; CX37), alpha 1 (GJA1 or connexin 43; CX43) and gamma 1 (GJC1 or connexin 45; CX45) are involved in cell communication and folliculogenesis. 7,12-dimethylbenz[a]anthracene (DMBA) alters Cx37 and Cx43 expression in cultured neonatal rat ovaries. Additionally, obesity has an additive effect on DMBA-induced ovarian cell death and follicle depletion, thus, we investigated in vivo impacts of obesity and DMBA on CX protein levels. Ovaries were collected from lean and obese mice aged 6, 12, 18, or 24 wks. A subset of 18 wk old mice (lean and obese) were dosed with sesame oil or DMBA (1 mg/kg; ip) for 14 days and ovaries collected 3 days thereafter. Cx43 and Cx45 mRNA and protein levels decreased (P < 0.05) after 18 wks while Cx37 mRNA and protein levels decreased (P < 0.05) after 24 wks in obese ovaries. Cx37 mRNA and antral follicle protein staining intensity were reduced (P < 0.05) by obesity while total CX37 protein was reduced (P < 0.05) in DMBA exposed obese ovaries. Cx43 mRNA and total protein levels were decreased (P < 0.05) by DMBA in both lean and obese ovaries while basal protein staining intensity was reduced (P < 0.05) in obese controls. Cx45 mRNA, total protein and protein staining intensity level were decreased (P < 0.05) by obesity. These data support that obesity temporally alters gap junction protein expression and that DMBA-induced ovotoxicity may involve reduced gap junction protein function. - Highlights: • Ovarian gap junction proteins are affected by ovarian aging and obesity. • DMBA exposure negatively impacts gap junction proteins. • Altered gap junction proteins may contribute to infertility.

  3. Embryotoxic effects of benzo[a]pyrene, chrysene and 7,12-dimethylbenz[a]-anthracene in petroleum hydrocarbon mixtures in mallard ducks

    USGS Publications Warehouse

    Hoffman, D.J.; Gay, M.L.

    1981-01-01

    Studies with different avian species have revealed that surface applications of microliter amounts of some crude and fuel oils that coat less than 70% of the egg surface result in considerable reduction in hatching with teratogenicity and stunted growth. Other stUdies have shown that the embryo toxicity is dependent on the aromatic hydrocarbon content, further suggesting that the toxicity is due to causes other than asphyxia. In the present study the effects of three polycyclic aromatic hydrocarbons identified in petroleum were examined on mallard (Anas platyrhynchos) embryo development. Addition of benzo[a]pyrene (BaP), chrysene, or 7,7 2-dimethylbenz[ a]anthracene (DMBA) to a synthetic petroleum hydrocarbon mixture of known composition and relatively low embryotoxicity resulted in embryo toxicity that was enhanced or equal to that of crude oil when 10 :I was applied externally to eggs at 72 h of development. The order of ability to enhance embryo toxicity was DMBA > BaP > chrysene. The temporal pattern of embryonic death was similar to that reported after exposure to crude oil, with additional mortality occurring after outgrowth of the chorioallantois. Retarded growth, as reflected by embryonic body weight, crown-rump length, and bill length, was accompanied by teratogenicity. Abnormal embryos exhibited extreme stunting; eye, brain, and bill defects; and incomplete ossification. Gas chromatographic-mass spectral analysis of externally treated eggs showed the passage of aromatic hydrocarbons including chrysene through the shell and shell membranes to the developing embryos. These findings suggest that the presence of polycyclic aromatic hydrocarbons in petroleum, including BaP, chrysene, and DMBA, significantly enhances the overall embryotoxicity in avian species.

  4. Derivation of transplantable 7,12-dimethylbenz(a)anthracene-induced chicken fibrosarcoma lines: differences in metastasizing properties and organ specificity

    SciTech Connect

    Galton, J.E.; Xue, B.; Hochwald, G.M.; Thorbecke, G.J.

    1982-08-01

    Transplantable 7,12-dimethylbenz(a)anthracene-induced SC chicken fibrosarcoma (CHCT-NYU) lines were studied for their ability to grow in internal organs after iv injection (artificial metastases) into 1- to 3-week-old chickens. Some tumor lines were recently derived, whereas others were studied after many serial subcutaneous transplantations. Artificial metastases were seen in the stomach, pancreas, lungs, heart, and muscle, and occasionally in the kidneys and liver. Agammaglobulinemic recipients showed more extensive organ involvement than normal recipients of the same age. Whole-body ..gamma..-irradiation enhanced the incidence of artificial metastases, particularly in lungs. Antibody from the serum of a primary tumor-bearing host reduced the growth of the corresponding tumor in many organs. The metastatic pattern of line CHCT-NYU4 was a relatively stable property. However, intravenous transplantation of tumor cells from line CHCT-NYU4 taken from the liver, lungs, and pancreas of a single recipient established sublines with changes in organ specificity. After a few such serial transplants of liver-derived tumor, a line was derived that grew virtually in the liver alone. A subline with preference for growth in lungs was also obtained, but its ability to grow in the pancreas persisted. A pancreas-derived tumor line also grew in the liver and lungs. Subcutaneous transplants of tissue fragments of the lung-derived tumor line caused the appearance of spontaneous metastases in lungs. The incidence of spontaneous metastases with the lung-derived line was much greater than that with the liver-derived line or with the original CHCT-NYU4 line.

  5. Involvement of retrotransposition of long interspersed nucleotide element-1 in skin tumorigenesis induced by 7,12-dimethylbenz[a]anthracene and 12-O-tetradecanoylphorbol-13-acetate.

    PubMed

    Okudaira, Noriyuki; Goto, Motohito; Yanobu-Takanashi, Rieko; Tamura, Masato; An, Akihiro; Abe, Yukiko; Kano, Shigeyuki; Hagiwara, Shotaro; Ishizaka, Yukihito; Okamura, Tadashi

    2011-11-01

    Tumor development induced by 7,12-dimethylbenz[a]anthracene (DMBA) plus 12-O-tetradecanoylphorbol-13-acetate (TPA) is a well-characterized model of multistep carcinogenesis. DMBA mutates the Ha-ras gene, whereas TPA promotes the growth of transformed cells by activating cellular signaling molecules. It remains to be clarified how repeated TPA treatment endows transformed cells with autonomous cell growth. Long interspersed nucleotide element-1 (L1) is an endogenous retroelement, and 80-100 copies of L1 function as autonomous mobile elements. Although the L1 retrotransposition (RTP) has been found in various human tumors, implying the possible mobility of L1 during carcinogenesis, little is known about how L1-RTP arises in tumor cells, owing to a lack of experimental models. To dissect the mechanism of L1-RTP during carcinogenesis, we established a line of transgenic mice carrying human L1 and enhanced green fluorescent protein (hL1-EGFP mice) and subjected them to DMBA/TPA-induced skin tumorigenesis. Of 15 skin tumors examined, 13 were positive for L1-RTP; L1-RTP was not detected in normal skin tissues adjacent to the tumors. Moreover, nine L1-RTP-positive tumors were positive for activated Ha-ras, and immunohistochemical analysis revealed cells positive for both L1-RTP and phosphorylated Stat3, a marker of tumor cells. Additional in vivo experiments suggested that L1-RTP occurred during tumor promotion by TPA. This is the first report on the involvement of L1-RTP in chemical carcinogenesis. We propose hL1-EGFP mice as a versatile system for investigating the mode of L1-RTP in tumor development and discuss the possible role of L1-RTP in tumorigenesis.

  6. Chemopreventive effects of Furan-2-yl-3-pyridin-2-yl-propenone against 7,12-dimethylbenz[a]anthracene-inducible genotoxicity

    SciTech Connect

    Hwang, Yong Pil; Han, Eun Hee; Choi, Jae Ho; Kim, Hyung Gyun; Lee, Kyung Jin; Jeong, Tae Cheon; Lee, Eung Seok; Jeong, Hye Gwang

    2008-05-01

    1-Furan-2-yl-3-pyridin-2-yl-propenone (FPP-3) is an anti-inflammatory agent with a propenone moiety and chemically synthesized recently. In this study, we examined the chemopreventive effect of FPP-3 on 7,12-dimethylbenz[a]anthracene (DMBA)-induced genotoxicity in MCF-7 cells. FPP-3 reduced the formation of the DMBA-DNA adduct. DMBA-induced CYP1A1 and CYP1B1 gene expression and enzyme activity were inhibited by FPP-3. It inhibited DMBA-induced aryl hydrocarbon receptor (AhR) transactivation and DMBA-inducible nuclear localization of the AhR. Induction of detoxifying phase II genes by chemopreventive agents represents a coordinated protective response against oxidative stress and neoplastic effects of carcinogens. Transcription factor NF-E2 related factor 2 (Nrf2) regulates antioxidant response element (ARE) of phase II detoxifying and antioxidant enzymes, such as glutathione S-transferase (GST) and NAD(P)H:quinone oxidoreductase (QR). FPP-3 increased the expression and enzymatic activity of GST and QR. Moreover, FPP-3 increased transcriptional activity of GST and QR. GST and QR induction and Nrf2 translocation by FPP-3 were blocked by the PKC inhibitor Goe6983, and the p38 inhibitor SB203580. These results reflected a partial role of PKC{delta} and p38 signaling in FPP-3-mediated GSTA and QR induction through nuclear translocation of Nrf2. Classically, chemopreventive agents either inhibit CYP metabolizing enzyme or induce phase II detoxifying enzymes. These results suggest that FPP-3 has a potent protective effect against DMBA-induced genotoxicity through modulating phase I and II enzymes and that it has potential as a chemopreventive agent.

  7. Daphnetin ameliorates 7,12-dimethylbenz[a]anthracene-induced mammary carcinogenesis through Nrf-2-Keap1 and NF-κB pathways.

    PubMed

    Kumar, Abhishek; Jha, S; Pattanayak, Shakti P

    2016-08-01

    Cancer is a faction of disorders that conjugated primarily with oxidative imbalance. In mammary carcinoma, oxidative stress secondarily changes various gene expressions and signalling pathways that bring genomic instability and mutagenic alterations that fascinating carcinogenesis. Several coumarin compounds are active against various malignancies. Among them, daphnetin (DAP) exhibits valuable safety and bioactivity profile that contributes towards its efficacy against cancer. In this study, the antioxidative and chemotherapeutic potential of DAP against 7,12-dimethylbenz(a)anthracene (DMBA)- induced mammary carcinogenesis was evaluated in female Sprague-Dawley rats. Besides this, we have determined the effect of DAP on Keap1-Nrf-2, associated HO-1 and NF-κB expressions behind the antioxidative and anti-proliferating activity. In our findings, a protective effect of DAP was established against lipid peroxidation, enzymic (Total SOD, MnSOD, CuZnSOD, CAT, GPx) and non-enzymic (GSH) antioxidative markers in serum, liver, kidney and breast tissue of both control and experimental groups. An up-regulation of protective Nrf-2 & HO-1 with a synchronized suppression in Keap1 & NF-κB mRNA and protein expressions were observed. DAP revealed the inhibition of p-AKT which accountable for decrease in NF-κB expressions but shown to be ineffective on p-ERK1/2. This study revealed that DAP inhibits mammary carcinogenesis through multiple mechanisms. Dual efficacy of DAP on Nrf-2-Keap1 pathway and NF-κB expressions propose it as a potential chemotherapeutic agent in mammary cancer management. PMID:27470383

  8. Vitamin D postpones the progression of epithelial ovarian cancer induced by 7, 12-dimethylbenz [a] anthracene both in vitro and in vivo

    PubMed Central

    Liu, Lizhi; Hu, Zhiyong; Zhang, Hemei; Hou, Yongfeng; Zhang, Zengli; Zhou, Guangming; Li, Bingyan

    2016-01-01

    Purpose Ovarian cancer is the most lethal malignancy of the female reproductive system, and the prevention and treatment of ovarian carcinoma are still far from optimal. Epidemiological studies reported that ovarian cancer risk was inversely associated with low level of 25-hydroxy vitamin D [25(OH)]. Therefore, this study focuses on exploring the chemoprevention of vitamin D on epithelial ovarian cancer induced by 7, 12-dimethylbenz [a] anthracene (DMBA). Methods The mouse ovarian surface epithelial cells were isolated from estrus mice by mild trypsinization and maintained in completed culture medium by repeated passaging. The malignant transformation of mouse ovarian surface epithelial cells was induced by DMBA in vitro. DMBA was directly injected into the bursa of mouse ovary to produce optimized in vivo ovarian cancer model. Results The results indicate that 1α,25 dihydroxyvitamin D3 may delay malignant transformation of mouse ovarian surface epithelial cells induced by DMBA and significantly decreased the colony formation rate from 18.4% to 3.2% (P<0.05). There was a negative correlation between incidence of DMBA-induced tumor and 25-hydroxy vitamin D level (R2=0.978, P<0.05). Vitamin D3 can delay the progression of ovarian cancer induced by DMBA, and the administration of vitamin D3 during the whole process worked more effectively than the administration only during tumor initiation or promotion. Moreover, we found the vitamin D3 increased the expression of E-cadherin and vitamin D receptor while it decreased the expression of β-catenin. Conclusion We succeeded in establishment of epithelial ovarian cancer models both in vitro and in vivo. The DMBA-implanted model in mice yields high incidence and specificity of epithelial derived tumors. We also found that vitamin D delays the progression of ovarian cancer. However, spontaneous epithelial ovarian carcinoma models are still to be explored for testing the preventive effects of vitamin D on epithelial ovarian

  9. Effect of phosphatidylinositol-3 kinase inhibition on ovotoxicity caused by 4-vinylcyclohexene diepoxide and 7, 12-dimethylbenz[a]anthracene in neonatal rat ovaries

    SciTech Connect

    Keating, Aileen F.; Mark, Connie J.; Sen, Nivedita; Sipes, I. Glenn; Hoyer, Patricia B.

    2009-12-01

    4-vinylcyclohexene diepoxide (VCD) is an ovotoxicant that specifically destroys primordial and small primary follicles in the ovaries of mice and rats. In contrast, 7,12-dimethylbenz[a]anthracene (DMBA) is ovotoxic to all ovarian follicle classes. This study investigated phosphatidylinositol-3 kinase signaling involvement in VCD- and DMBA-induced ovotoxicity. Postnatal day (PND) 4 Fischer 344 (F344) rat whole ovaries were cultured for 2-12 days in vehicle control, VCD (30 muM), or DMBA (1 muM), +- PI3 kinase inhibitor LY294002 (20 muM) or its inactive analog LY303511 (20 muM). Following culture, ovaries were histologically evaluated, and healthy follicles were classified and counted. PI3 kinase inhibition had no effect on primordial follicle number, but reduced (P < 0.05) small primary and larger follicles beginning on day 4. VCD caused primordial and small primary follicle loss (P < 0.05) beginning on day 6. With PI3 kinase inhibition, VCD did not affect primordial follicles (P > 0.05) at any time, but did cause loss (P < 0.05) of small primary follicles. DMBA exposure caused primordial and small primary follicle loss (P < 0.05) on day 6. Further, DMBA-induced primordial and small primary follicle loss was greater with PI3 kinase inhibition (P < 0.05) than with DMBA alone. These results support that (1) PI3 kinase mediates primordial to small primary follicle recruitment, (2) VCD, but not DMBA, enhances ovotoxicity by increasing primordial to small primary follicle recruitment, and (3) in addition to xenobiotic-induced ovotoxicity, VCD is also a useful model chemical with which to elucidate signaling mechanisms involved in primordial follicle recruitment.

  10. Comparison of the metabolic activation of 7, 12-dimethylbenz(a)anthracene by a human hepatoma cell line (HepG2) and low passage hamster embryo cells

    SciTech Connect

    DiGiovanni, J.; Singer, J.M.; Diamond, L.

    1984-07-01

    Under similar conditions of cell-mediated mutagenesis, secondary hamster embryo (HE) cells were much more effective than were cells of the human hepatoma cell line, HepG2 , in activating 7, 12-dimethylbenz(a)anthracene (DMBA) to metabolites mutagenic for V79 Chinese hamster cells. At the same dose of DMBA (0.1 microgram/ml), mutation induction (6-thioguanine resistance) with HE cells as activators was about ten times greater than with HepG2 cells as activators. Both cell types rapidly metabolized DMBA. HepG2 cells converted DMBA primarily to water-soluble derivatives that were neither sulfates nor glucuronides, whereas HE cells converted DMBA to a variety of organic solvent-soluble and water-soluble metabolites. The major water-soluble metabolites produced by HE cells were phenol-glucuronides. In HepG2 cells, binding of DMBA to DNA reached a maximum value of 12.1 pmol/mg DNA at 12 hr, whereas in HE cells, binding reached a peak value of 180.7 pmol/mg DNA at 24 hr. Despite this difference in total binding between the two cell types, the pattern of DNA adducts formed was nearly identical. The results indicate that the marked difference in the ability of HepG2 and HE cells to activate DMBA in cell-mediated mutation assays is not due to a lower metabolizing capacity of HepG2 cells for DMBA. Rather, significant differences in the metabolic pathways used by the two cell types lead to a marked reduction in DNA-binding metabolites in one cell type (HepG2) compared to the other (HE).

  11. Influence of ionizing radiation and 7,12-dimethylbenz(a)anthracene on the expression of mammary ductal dysplasia in mice

    SciTech Connect

    Ethier, S.P.

    1982-01-01

    These studies were undertaken to determine if altered growth potential of mammary epithelial cells could be detected in outgrowths derived from monodispersed mammary cells of virgin female BALB/c mice previously exposed to ionizing radiation or 7,12-dimethylbenz(a)anthracene (DMBA). Monodispersed mammary cells were obtained by enzymatic dissociation of mammary tissues of 12-week-old virgin female BALB/c mice. Twenty-four hours prior to cell dissociation, donor animals were exposed to either ..gamma..-ray irradiation or DMBA, while control donors were untreated. Mammary outgrowths were then derived from the donor cells by injecting either 10/sup 5/ or 10/sup 4/ cells into the gland free mammary fat pads of three-week-old virgin female BALB/c mice. In the initial studies all outgrowths were removed 10 weeks after injection of cells. The outgrowths that resulted were examined at the whole mount and histological level and were classified as having a normal ductal architecture or as having ductal dysplasia or alveolar adenosis. Outgrowths exhibiting ductal dysplasia were further classified as having mild or severe epithelial hyperplasia. The data indicated that treatment of donor animals with either ..gamma..-radiation or DMBA could result in an increased incidence of ductal dysplasias over control levels. Further, the incidence of lesions observed in all groups was influenced by the number of cells used to derive the outgrowths in that lesions were more frequent in outgrowths derived from 10/sup 4/ rather than 10/sup 5/ cells. The findings of these experiments indicate that acquisition of altered growth potential by mammary cells that results in expression of ductal dysplasia occurs soon after carcinogen treatment and that deriving mammary outgrowths from dissociated cells results in enhanced expression of these lesions.

  12. Proteomic analysis of the murine liver in response to a combined exposure to psychological stress and 7,12-dimethylbenz(a)anthracene.

    PubMed

    Flint, Melanie S; Hood, Brian L; Sun, Mai; Stewart, Nicolas A; Jones-Laughner, Jacqueline; Conrads, Thomas P

    2010-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are environmental carcinogens implicated to underlie development of several types of cancers. Cytochrome P450 (CYP) enzymes play key roles in the conversion of PAHs to highly potent carcinogens, namely diol epoxides. 7,12-Dimethylbenz(a)anthracene (DMBA), a PAH, is highly carcinogenic, where in mouse models it is known to be responsible for initiating tumor formation in many organs including mammary tissues, ovaries, and skin. Psychological stress, via release of biochemical mediators, can greatly impact carcinogenesis. The present investigation examined the hypothesis that psychological stress modulates metabolism and carcinogenicity of DMBA through alteration of key drug metabolizing enzyme abundance levels in the liver utilizing mass spectrometry-based proteomics. To test this hypothesis, four groups of mice were treated as follows: nonstressed, stressed, nonstressed/DMBA-exposed, and stressed/DMBA-exposed, where the stressor was a well-accepted model of restraint. Liver proteins were extracted, resolved by one-dimensional gel electrophoresis, digested in-gel with trypsin, and analyzed by liquid chromatography-tandem mass spectrometry. This investigation resulted in the unique identification of 59 isoforms of CYP enzymes. Changes in protein abundances derived from spectral counting indicates that stress alone results in increases in the abundance of proteins responsive to oxidative stress, along with Phase I and II metabolizing enzymes, such as CYP2J5 and UDP glucoronytransferases. The proteomic results further indicate that exposure to DMBA induces increases in the abundance of CYP1A2 and serine protease inhibitors and decreases the abundance of CYP4 V3. Finally, significant changes in the abundance of proteins such as CYP1A2, CYP3A11, and Topoisomerase-2 were found between nonstressed and stressed/DMBA-treated mice. These data support the hypothesis that psychological stress modulates DMBA-induced regulation of drug

  13. Incorporation and electron transfer of anthracene in pores of ZSM-5 zeolites. Effect of Brønsted acid site density.

    PubMed

    Hureau, Matthieu; Moissette, Alain; Marquis, Séverine; Brémard, Claude; Vezin, Hervé

    2009-08-01

    The sorption course of anthracene (ACENE-3) into Brønsted-acidic medium pore MFI zeolites was monitored by in situ EPR and diffuse reflectance UV-visible absorption over one year. Weighed amounts of solid ACENE-3 were merely exposed to H(n)ZSM-5 (H(n)(AlO(2))(n)(SiO(2))(96-n)), with the following Brønsted acid site (BAS) densities, n = 0.0, 0.17, 0.57, 0.95, 2.0, 3.4, 6.6, dehydrated at 623 K under argon. The weighed amounts correspond to 1 ACENE-3 per zeolite unit cell. ACENE-3 is found to be incorporated as intact molecules in purely siliceous MFI (silicalite-1). Monte Carlo simulations indicate that ACENE-3 lies in the intersection of straight and zigzag channels. In contrast, the presence of BASs on the inner surface of channels induces spontaneous ionization of ACENE-3 (ionization potential = 7.44 eV). The charge separation as ACENE-3*(+)@H(n)ZSM-5*(-) is caused by the strong Coulombic field gradient of Si-O(-)(H(+))-Al BAS in the absence of any Lewis acid site. The rate and yield of ionization are found to increase dramatically with BAS density increase. The stabilization of ACENE-3*(+)@H(n)ZSM-5*(-) is explained by the tight fit between the rod-shape ACENE-3 and the channel dimensions and especially by the compartmentalization of ejected electrons as AlO(4)H*(-) centers away from the initial site of ionization. The final charge recombination occurs after more than one year and leads to ACENE-3 occluded in the straight channel in close proximity to BAS without any protonation of ACENE-3 (pK(a) = -13.5).

  14. Quantitation of benzo(a)pyrene and 7,12-dimethylbenz(a)anthracene binding to nuclear macromolecules in human and rat mammary epithelial cells.

    PubMed

    Moore, C J; Eldridge, S R; Tricomi, W A; Gould, M N

    1987-05-15

    Our laboratory has developed virtually identical techniques for the isolation and culture of mammary epithelial cells (MEC) from rats and humans. In a cell-mediated mutagenesis assay, rat MEC activated 7,12-dimethylbenz(a)anthracene (DMBA) but not benzo(a)pyrene [B(a)P] to mutagenic forms, and the opposite pattern was found with human MEC. These species-specific patterns were not readily explained by either qualitative or quantitative differences in Phase I metabolism of these compounds. In contrast, relative levels of covalent binding of these compounds to DNA in the human and rat cells under identical assay conditions generally parallel the pattern of the mutagenesis results, while not reflecting the absolute levels of metabolism in each system. The ability of the rat MEC to bind relatively higher levels of DMBA than B(a)P to nuclear DNA, and the reversed pattern in human MEC, was found at all incubation times tested between 6 and 48 h. Culture density was found to exert a greater effect on the levels of PAH-DNA binding in rat than in human cells, but in neither case did it affect the ratio of DMBA to B(a)P binding within a species. C2SO4 gradient separation of nuclear macromolecules from PAH-treated MEC revealed that the relative DNA binding levels of DMBA and B(a)P did not correlate with relative levels of nuclear protein binding. For both species, nuclear (DNA + protein) binding levels of B(a)P were approximately 2-fold higher than DMBA. However, these binding levels were 4 to 5-fold higher for both carcinogens in the human than in the rat MEC. The species-specific patterns of PAH activation shown by these cells suggest that caution should be used in extrapolating rodent carcinogenesis data to humans, for either quantitative or qualitative purposes.

  15. Synthesis and structure of dimeric anthracene-9-carboxylato bridged dinuclear erbium(III) complex, [Er(2)(9-AC)(6)(DMF)(2)(H(2)O)(2)].

    PubMed

    Kusrini, Eny; Adnan, Rohana; Saleh, Muhammad I; Yan, Lim-Kong; Fun, Hoong-Kun

    2009-05-01

    We study the influence of the bulky aromatic rings, e.g. anthracence-9-carboxylic acid (9-ACA) with a large conjugated pi-system on the structure and spectroscopic properties of [Er(2)(9-AC)(6)(DMF)(2)(H(2)O)(2)] complex where 9-AC=anthracence-9-carboxylato and DMF=N,N'-dimethylformamide. The complex has been prepared from the erbium chloride and 9-ACA in the mixture of H(2)O:DMF solution (4:1, v/v) followed by pH adjustment to 6. The complex is crystallized in a monoclinic system with space group P2(1)/n. The two Er(III) ions are double bridged by the deprotonated carboxyl groups of two 9-AC anions (O1 and O1A), forming an eight-coordination number. The chelating bidentate (O,O), chelating-bridging tridentate (O,O,O') and monodentate of 9-AC anions are observed in the dinuclear [Er(2)(9-AC)(6)(DMF)(2)(H(2)O)(2)] complex. The Er-Er distance is 4.015A in the dimeric unit. Intramolecular O-Hcdots, three dots, centeredO and C-Hcdots, three dots, centeredO hydrogen bonds as well as numerous of intermolecular C-Hcdots, three dots, centeredpi interactions between the anthracene rings by edge-to-face interactions linked the dinuclear dimeric units into two-dimensional supramolecular network in a propeller-arrangement. Electronic absorption spectra of the Er(III) complex and its salt were measured. The emission spectrum of the complex is composed of a broad band due to the emission of intraligand pi*-->pi transition from the 9-AC anions and a shoulder peak originating from the 4f-4f emission transition of the Er(III) ions. The complex has a high thermal stability which can be attributed to the effectively increase the rigidity of the 9-AC anions.

  16. Uptake and phytotoxicity of anthracene and benzo[k]fluoranthene applied to the leaves of celery plants (Apium graveolens var. secalinum L.).

    PubMed

    Wieczorek, Jolanta; Sienkiewicz, Stanisław; Pietrzak, Monika; Wieczorek, Zbigniew

    2015-05-01

    The above-ground parts of celery plants were exposed to two polycyclic aromatic hydrocarbons (PAHs): 3-ring anthracene (ANT) and 5-ring benzo[k]fluoranthene (BkF), and the combination of ANT and BkF. After 43 days of exposure (overall dose of 1325µg/plant), celery plants retained only 1.4% of the total dose of ANT and 17.5% of the total dose of BkF. After exposure to a combination of ANT and BkF (1325µg of each compound per plant), the average ANT concentrations were more than twofold higher in/on leaf blades, whereas BkF levels were insignificantly higher. Under natural photoperiod conditions equivalent to a normal day, the combined application of ANT and BkF to the above-ground parts of celery plants slowed down physicochemical transformations of ANT. A similar effect was observed when PAHs were applied to glass surfaces. The combination of both PAHs probably led to stacking interactions, which decreased volatilization, in particular of ANT. Phytotoxicity of ANT and BkF could not be unambiguously established based on the results of this study. In all analyzed treatments, the chlorophyll content of leaf blades remained unchanged. Foliar application of ANT reduced ascorbic acid levels in all analyzed plant parts and increased the total acidity of celery leaves. In all experimental treatments, the total phenolic content of leaves increased up to 15%. Interestingly, ANT and BkF did not produce cumulative effects when applied in combination (when total PAH concentrations per plant were twofold higher).

  17. Impact of obesity on 7,12-dimethylbenz[a]anthracene-induced altered ovarian connexin gap junction proteins in female mice

    PubMed Central

    Ganesan, Shanthi; Nteeba, Jackson; Keating, Aileen F.

    2014-01-01

    The ovarian gap junction proteins alpha 4 (GJA4 or connexin 37; CX37), alpha 1 (GJA1 or connexin 43; CX43) and gamma 1 (GJC1 or connexin 45; CX45) are involved in cell communication and folliculogenesis. 7,12-dimethylbenz[a]anthracene (DMBA) alters Cx37 and Cx43 expression in cultured neonatal rat ovaries. Additionally, obesity has an additive effect on DMBA-induced ovarian cell death and follicle depletion, thus, we investigated in vivo impacts of obesity and DMBA on CX protein levels. Ovaries were collected from lean and obese mice aged 6, 12, 18, or 24 wks. A subset of 18 wk old mice (lean and obese) were dosed with sesame oil or DMBA (1mg/kg; ip) for 14 days and ovaries collected 3 days thereafter. Cx43 and Cx45 mRNA and protein levels decreased (P < 0.05) after 18 wks while Cx37 mRNA and protein levels decreased (P < 0.05) after 24 wks in obese ovaries. Cx37 mRNA and antral follicle protein staining intensity were reduced (P < 0.05) by obesity while total CX37 protein was reduced (P < 0.05) in DMBA exposed obese ovaries. Cx43 mRNA and total protein levels were decreased (P < 0.05) by DMBA in both lean and obese ovaries while basal protein staining intensity was reduced (P < 0.05) in obese controls. Cx45 mRNA, total protein and protein staining intensity level were decreased (P < 0.05) by obesity. These data support that obesity temporally alters gap junction protein expression and that DMBA-induced ovotoxicity may involve reduced gap junction protein function. PMID:25447408

  18. Chronic unpredictable stress (CUS) enhances the carcinogenic potential of 7,12-dimethylbenz(a)anthracene (DMBA) and accelerates the onset of tumor development in Swiss albino mice.

    PubMed

    Suhail, Nida; Bilal, Nayeem; Hasan, Shirin; Ahmad, Ausaf; Ashraf, Ghulam Md; Banu, Naheed

    2015-11-01

    Social stressors evolving from individual and population interactions produce stress reactions in many organisms (including humans), influencing homeostasis, altering the activity of the immunological system, and thus leading to various pathological states including cancer and their progression. The present study sought to validate the effectiveness of chronic unpredictable stress (CUS) in cancer promotion and to assess oxidative stress outcomes in terms of various in vivo biochemical parameters, oxidative stress markers, DNA damage, and the development of skin tumors in Swiss albino mice. Animals were randomized into different groups based on their exposure to CUS alone, 7,12-dimethylbenz(a)anthracene (DMBA) alone (topical), and DMBA-12-O-tetradecanoylphorbol-13-acetate (TPA) (topical) and exposure to CUS prior to DMBA or DMBA-TPA treatments and sacrificed after 16 weeks of treatment. Prior exposure to CUS significantly increased the pro-oxidant effect of carcinogen, depicted by compromised levels of antioxidants in the circulation and skin, accompanied by enhanced lipid peroxidation, plasma corticosterone, and marker enzymes as compared to DMBA-alone or DMBA-TPA treatments. DNA damage results corroborated the above biochemical outcomes. Also, the development of skin tumors (in terms of their incidence, tumor yield, and tumor burden) in mice in the presence and absence of stress further strongly supported our above biochemical measurements. CUS may work as a promoter of carcinogenesis by enhancing the pro-oxidant potential of carcinogens. Further studies may be aimed at the development of interventions for disease prevention by identifying the relations between psychological factors and DNA damage. PMID:26272695

  19. Synthesis and characterization of novel, optically active polyamides derived from S-valine natural amino acid and bulky anthracenic side chain.

    PubMed

    Mallakpour, Shadpour; Mirkarimi, Fatemeh

    2010-11-01

    This is the first description of the application of molten tetrabutylammonium bromide (TBAB) in the presence of triphenyl phosphite (TPP) for the synthesis of novel polyamides (PAs). Monomer diacid, 5-[(9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboximido)-3-methylbutanoylamino]isophthalic acid (4), having anthracenic and amino acid S-valine pendant group, was synthesized in four steps. Several novel, optically active PAs were prepared by the condensation of synthesized diacid monomer 4 with various aromatic diamines using two different techniques: a mixture of N-methyl-2-pyrrolidone (NMP)/TPP/pyridine/calcium chloride (method I) and combination of TPP with TBAB (method II). The main goal of the present paper was to prepare novel PAs in a green media by removal of toxic reagents. Therefore, TBAB/TPP was used as a novel, easy, safe and eco-friendly method for the preparation of aromatic PAs. This method is compared with the polymerization reaction under conventional solvent and in the case of TBAB as a new method, higher yields, inherent viscosities and thermally stable of PAs are gained. The resulting polymers showed good solubility in polar aprotic solvents such as dimethyl sulfoxide, NMP, N,N-dimethylacetamide and N,N-dimethylformamide. These polymers are characterized with respect to chemical structure and purity by means of specific rotation experiments, FT-IR, 1H NMR spectroscopy techniques and elemental analysis. The obtained PAs exhibit good thermal stability up to 335°C for 10% weight loss in nitrogen atmosphere and glass transition temperatures fell in the rang of 177-185°C. PMID:20352462

  20. Apigenin prevents development of medroxyprogesterone acetate-accelerated 7,12-dimethylbenz(a)anthracene-induced mammary tumors in Sprague-Dawley rats

    PubMed Central

    Mafuvadze, Benford; Benakanakere, Indira; Lopez, Franklin; Besch-Williford, Cynthia; Ellersieck, Mark R.; Hyder, Salman M.

    2011-01-01

    The use of progestins as a component of hormone replacement therapy has been linked to an increase in breast cancer risk in postmenopausal women. We have previously shown that medroxyprogesterone acetate (MPA), a commonly administered synthetic progestin, increases production of the potent angiogenic factor vascular endothelial growth factor (VEGF) by tumor cells, leading to the development of new blood vessels and tumor growth. We sought to identify nontoxic chemicals that would inhibit progestin-induced tumorigenesis. We used a recently developed progestin-dependent mammary cancer model in which tumors are induced in Sprague-Dawley rats by 7,12-dimethylbenz(a)anthracene (DMBA) treatment. The flavonoid apigenin, which we previously found to inhibit progestin-dependent VEGF synthesis in human breast cancer cells in vitro, significantly delayed the development of, and decreased the incidence and multiplicity of, MPA-accelerated DMBA-induced mammary tumors in this animal model. Whereas apigenin decreased the occurrence of such tumors, it did not block MPA-induced intraductal and lobular epithelial cell hyperplasia in the mammary tissue. Apigenin blocked MPA-dependent increases in VEGF, and suppressed VEGF receptor-2 (VEGFR-2) but not VEGFR-1 in regions of hyperplasia. No differences were observed in estrogen or progesterone receptor levels, or the number of estrogen receptor-positive cells, within the mammary gland of MPA-treated animals administered apigenin, MPA-treated animals, and placebo treated animals. However, the number of progesterone receptor-positive cells was reduced in animals treated with MPA or MPA and apigenin compared with those treated with placebo. These findings suggest that apigenin has important chemopreventive properties for those breast cancers that develop in response to progestins. PMID:21505181

  1. Relative induction potency of benzo(a)pyrene and dibenzo(a,h) anthracene in environmental samples using the H4IIE cell bioassay

    SciTech Connect

    Willett, K.; Gardinali, P.; Sericano, J.; Wade, T.; Safe, S.

    1995-12-31

    The induction of ethoxyresorufin O-deethylase (EROD) activity in H4IIE cells has proven to be a useful assay for assessing the toxic equivalents of complex mixtures of halogenated aromatic hydrocarbons and related compounds in environmental samples. However, there is often a discrepancy between bioassay induction results and toxic equivalents calculated from chemical analysis of samples; the former yielding higher I-TEQs (induction/toxic equivalents). Polynuclear aromatic hydrocarbons (PAHs) are a class of chemicals which can significantly contribute to I-TEQ estimates. Benzo(a)pyrene (BAP) and dibenzo(a,h)anthracene (DBA) are both carcinogenic PAHs found in environmental samples, specifically oysters (Crassostrea virginica) collected from Galveston Bay. Dose-response studies were conducted with H4IIE cells to determine the relative induction potency of these two PAHs relative to 2,3,7,8-TCDD. Using probit analysis, the I-TEFs were 0.00144 and 0.0095 for BAP and DBA, respectively. Reconstituted PAH mixtures (744 to 4,466 ng/g total PAHs) with constant percentages of BAP (4.5%) and DEA (3.5%) yielded bioassay derived I-TEQs which ranged from 0.52 to 1.44 ng/g. Oysters treated with the same PAH mix for 30 days differentially accumulated the DBA and BAP over the time course. The bioassay derived I-TEQs of extracts from these oysters ranged from 0.99 to 6.14 ng/g whereas the calculated values using only the I-TEQs of BAP and BDA ranged from 0.04 to 0.57 accounting for only 5--10% of the observed induction response. These results indicate that presence of other PAHs in the treated oyster extracts are highly active as inducers of EROD activity in the H4IIE bioassay.

  2. Characterization of molecular mass ranges of two coal tar distillate fractions (creosote and anthracene oils) and aromatic standards by LD-MS, GC-MS, probe-MS and size-exclusion chromatography

    SciTech Connect

    T.J. Morgan; A. George; P. A'lvarez; M. Millan; A.A. Herod; R. Kandiyoti

    2008-09-15

    Laser-desorption mass spectrometry (LD-MS) method development was undertaken to improve estimates of mass ranges for complex hydrocarbon mixtures. A creosote oil, an anthracene oil, and a mixture of known polynuclear aromatic hydrocarbon (PAH) compounds were examined. The formation of cluster ions was possible without overloading the detector system. These multimer ions overlapped with higher-mass ion signals from the sample. However, careful balancing of sample concentration, laser power, total ion current, and delayed ion extraction appears to show high-mass materials without generating high-mass multimer (artifact) ions. It is possible to suppress the formation of cluster ions by keeping low target concentrations and, consequently, low gas phase concentrations formed by the laser pulse. The principal method used in this work was the fractionation of samples by planar chromatography followed by successive LD-MS analysis of the separated fractions directly from the chromatographic plates. This method separated the more abundant small molecules from the less abundant large molecules to permit the generation of their mass spectra independently, as well as reducing the concentration of sample by spreading over the PC-plate. The technique demonstrably suppressed multimer formation and greatly improved the reproducibility of the spectra. Results showed the presence of molecule ions in the ranges m/z 1000-2000 for the anthracene oil sample and m/z 600-1500 for the creosote oil sample, tailing off to m/z about 5,000. The creosote oil contained significantly less of this high-mass material than the anthracene oil sample, and in both cases, high-mass material was only present in low quantities. The method outlined in the paper appears directly applicable to the characterization of heavier coal and petroleum derived fractions. 44 refs., 14 figs., 3 tabs.

  3. 4-[2-(Anthracen-9-yl­methyl­idene)hydrazinyl­idene]-3-chloro-1-methyl-3,4-dihydro-1H-2λ6,1-benzothia­zine-2,2-dione

    PubMed Central

    Shafiq, Muhammad; Tahir, M. Nawaz; Khan, Islam Ullah; Bokhari, Tanveer Hussain; Asghar, Muhammad Nadeem

    2012-01-01

    In the title compound, C24H18ClN3O2S, the dihedral angle between the benzene ring and the anthracene ring system is 41.10 (8)°. The thia­zine ring has a half-chair conformation and the Cl atom is in an axial orientation. In the crystal, mol­ecules are linked by C—H⋯O inter­actions, generating C(8) chains along [100]. A C—H⋯N short contact occurs in the mol­ecule, generating an S(6) ring. PMID:22719565

  4. Synthesis of some novel 1-(2-naphthyl)-2-(imidazol-1-yl)ethanone oxime ester derivatives and evaluation of their anticonvulsant activity.

    PubMed

    Karakurt, Arzu; Alagöz, Mehmet A; Sayoğlu, Burcu; Calış, Unsal; Dalkara, Sevim

    2012-11-01

    Twenty-three new oxime ester derivatives of nafimidone were synthesized with the prospect of potential anticonvulsant activities. MES and ScM tests were employed for their anticonvulsant activities and rotorod test for neurological deficits. Eighteen compounds were found to be protective against MES seizures. Alkyl (1-8) and arylalkyl (9, 10) oxime ester derivatives were found to be more active than aryl oxime ester derivatives (11-23). Five compounds (2, 3, 7, 9, 10), which were protective at 0.5 h at the doses of 30 mg/kg and higher in MES test, showed the highest activity. Compound 17 was the most active one in ScM test at all dose levels at 4 h.

  5. 9-Anthracene carboxylic acid is more suitable than DIDS for characterization of calcium-activated chloride current during canine ventricular action potential.

    PubMed

    Váczi, Krisztina; Hegyi, Bence; Ruzsnavszky, Ferenc; Kistamás, Kornél; Horváth, Balázs; Bányász, Tamás; Nánási, Péter P; Szentandrássy, Norbert; Magyar, János

    2015-01-01

    Understanding the role of ionic currents in shaping the cardiac action potential (AP) has great importance as channel malfunctions can lead to sudden cardiac death by inducing arrhythmias. Therefore, researchers frequently use inhibitors to selectively block a certain ion channel like 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) and 9-anthracene carboxylic acid (9-AC) for calcium-activated chloride current (ICl(Ca)). This study aims to explore which blocker is preferable to study ICl(Ca). Whole-cell voltage-clamp technique was used to record ICa,L, IKs, IKr and IK1, while action potentials were measured using sharp microelectrodes. DIDS- (0.2 mM) and 9-AC-sensitive (0.5 mM) currents were identical in voltage-clamp conditions, regardless of intracellular Ca(2+) buffering. DIDS-sensitive current amplitude was larger with the increase of stimulation rate and correlated well with the rate-induced increase of calcium transients. Both drugs increased action potential duration (APD) to the same extent, but the elevation of the plateau potential was more pronounced with 9-AC at fast stimulation rates. On the contrary, 9-AC did not influence either the AP amplitude or the maximal rate of depolarization (V max), but DIDS caused marked reduction of V max. Both inhibitors reduced the magnitude of phase-1, but, at slow stimulation rates, this effect of DIDS was larger. All of these actions on APs were reversible upon washout of the drugs. Increasing concentrations of 9-AC between 0.1 and 0.5 mM in a cumulative manner gradually reduced phase-1 and increased APD. 9-AC at 1 mM had no additional actions upon perfusion after 0.5 mM. The half-effective concentration of 9-AC was approximately 160 μM with a Hill coefficient of 2. The amplitudes of ICa,L, IKs, IKr and IK1 were not changed by 0.5 mM 9-AC. These results suggest that DIDS is equally useful to study ICl(Ca) during voltage-clamp but 9-AC is superior in AP measurements for studying the physiological role of

  6. 7,12-Dimethylbenz(a)anthracene-induced genotoxicity on bone marrow cells from mice phenotypically selected for low acute inflammatory response.

    PubMed

    Katz, Iana Suly Santos; Albuquerque, Layra Lucy; Suppa, Alessandra Paes; da Silva, Graziela Batista; Jensen, José Ricardo; Borrego, Andrea; Massa, Solange; Starobinas, Nancy; Cabrera, Wafa Hanna Koury; De Franco, Marcelo; Borelli, Primavera; Ibañez, Olga Martinez; Ribeiro, Orlando Garcia

    2016-01-01

    Exposure to polycyclic aromatic hydrocarbon (PAH) environmental contaminants has been associated with the development of mutations and cancer. 7,12-Dimethylbenz(a)anthracene ( DMBA), a genotoxic agent, reacts with DNA directly, inducing p53-dependent cytotoxicity resulting in cell death by apoptosis or giving rise to cancer. DMBA metabolism largely depends on activation of the aryl hydrocarbon receptor (AhR). Mice phenotypically selected for high (AIRmax) or low (AIRmin) acute inflammatory response present a complete segregation of Ahr alleles endowed with low (Ahr(d)) or high (Ahr(b1)) affinity to PAHs, respectively. To evaluate the role of AhR genetic polymorphism on the bone marrow susceptibility to DMBA, AIRmax and AIRmin mice were treated with a single intraperitoneal injection of DMBA (50mg/kg b.w.) in olive oil. Bone marrow cells (BMCs) were phenotyped by both flow cytometry and cytoslide preparations. Despite a significant decrease in total cell count in BM from AIRmin mice, there was an increase of blast cells and immature neutrophils at 1 and 50 days after DMBA treatment, probably due to a cell-cycle blockade at the G1/S transition leading to immature stage cell production. A panel of proteins related to cell cycle regulation was evaluated in immature BM cells (Lin(-)) by Western Blot, and DNA damage and repair were measured using an alkaline version of the Comet assay. In Lin(-) cells isolated from AIRmin mice, high levels were found in both p53 and p21 protein contents in contrast with the low levels of CDK4 and Ciclin D1. Evaluation of DNA repair in DMBA-treated BMCs, indicated long-lasting genotoxicity and cytotoxicity in BMC from AIRmin mice and a blockade of cell cycle progression. On the other hand, AIRmax mice have a high capacity of DNA damage repair and protection. These mechanisms can be associated with the differential susceptibility to the toxic and carcinogenic effects of DMBA observed in these mice. PMID:26687588

  7. Acute 7,12-dimethylbenz[a]anthracene exposure causes differential concentration-dependent follicle depletion and gene expression in neonatal rat ovaries

    SciTech Connect

    Madden, Jill A.; Hoyer, Patricia B.; Devine, Patrick J.; Keating, Aileen F.

    2014-05-01

    Chronic exposure to the polycyclic aromatic hydrocarbon 7,12-dimethylbenz[a]anthracene (DMBA), generated during combustion of organic matter including cigarette smoke, depletes all ovarian follicle types in the mouse and rat, and in vitro models mimic this effect. To investigate the mechanisms involved in follicular depletion during acute DMBA exposure, two concentrations of DMBA at which follicle depletion has (75 nM) and has not (12.5 nM) been observed were investigated. Postnatal day four F344 rat ovaries were maintained in culture for four days before a single exposure to vehicle control (1% DMSO; CT) or DMBA (12 nM; low-concentration or 75 nM; high-concentration). After four or eight additional days of culture, DMBA-induced follicle depletion was evaluated via follicle enumeration. Relative to control, DMBA did not affect follicle numbers after 4 days of exposure, but induced large primary follicle loss at both concentrations after 8 days; while, the low-concentration DMBA also caused secondary follicle depletion. Neither concentration affected primordial or small primary follicle number. RNA was isolated and quantitative RT-PCR performed prior to follicle loss to measure mRNA levels of genes involved in xenobiotic metabolism (Cyp2e1, Gstmu, Gstpi, Ephx1), autophagy (Atg7, Becn1), oxidative stress response (Sod1, Sod2) and the phosphatidylinositol 3-kinase (PI3K) pathway (Kitlg, cKit, Akt1) 1, 2 and 4 days after exposure. With the exception of Atg7 and cKit, DMBA increased (P < 0.05) expression of all genes investigated. Also, BECN1 and pAKT{sup Thr308} protein levels were increased while cKIT was decreased by DMBA exposure. Taken together, these results suggest an increase in DMBA bioactivation, add to the mechanistic understanding of DMBA-induced ovotoxicity and raise concern regarding female low concentration DMBA exposures. - Highlights: • Acute DMBA exposures induce large primary and/or secondary follicle loss. • Acute DMBA exposure did not impact

  8. Evaluation of ovotoxicity induced by 7, 12-dimethylbenz[a]anthracene and its 3,4-diol metabolite utilizing a rat in vitro ovarian culture system

    SciTech Connect

    Igawa, Yoshiyuki; Keating, Aileen F. Rajapaksa, Kathila S.; Sipes, I. Glenn; Hoyer, Patricia B.

    2009-02-01

    The polycyclic aromatic hydrocarbon 7, 12-dimethylbenz[a]anthracene, (DMBA), targets and destroys all follicle types in rat and mouse ovaries. DMBA requires bioactivation to DMBA-3,4-diol-1,2-epoxide for ovotoxicity via formation of the intermediate, DMBA-3,4-diol (catalyzed by microsomal epoxide hydrolase; mEH). mEH was shown to be involved in DMBA bioactivation for ovotoxicity induction in B6C3F{sub 1} mouse ovaries. The current study compared DMBA and DMBA-3,4-diol mediated ovotoxicity, and investigated mEH involvement in DMBA-3,4-diol bioactivation in Fischer 344 (F344) rat ovary. F344 postnatal day (PND) 4 rat ovaries were cultured in vehicle control or media containing 1) DMBA or DMBA-3,4-diol (12.5 nM - 1 {mu}M; 15 days); 2) DMBA (1 {mu}M; 6 h - 15 days); and 3) DMBA (1 {mu}M) or DMBA-3,4-diol (75 nM) {+-} the mEH activity inhibitor cyclohexene oxide (CHO; 2 mM; 4 days). Ovaries were histologically evaluated and mEH mRNA and protein were measured by reverse transcriptase PCR or Western blotting, respectively. Ovotoxicity following 15 days of culture occurred (P < 0.05) at lower concentrations of DMBA-3,4-diol (12.5 nM - primordial; 75 nM - primary) than DMBA (75 nM - primordial; 375 nM - primary). The temporal pattern of mEH expression following DMBA exposure showed mRNA up-regulation (P < 0.05) on day 2, with increased protein (P < 0.05) on day 4, the earliest time of observed follicle loss (P < 0.05). mEH inhibition prevented DMBA-induced, but not DMBA-3,4-diol-induced ovotoxicity. These results demonstrate a conserved response in mice and rats for ovarian mEH involvement in DMBA bioactivation to its ovotoxic, 3,4-diol-1,2-epoxide form.

  9. Molecular conformational analysis, vibrational spectra, NBO, NLO, HOMO-LUMO and molecular docking studies of ethyl 3-(E)-(anthracen-9-yl)prop-2-enoate based on density functional theory calculations.

    PubMed

    Mary, Y Sheena; Varghese, Hema Tresa; Panicker, C Yohannan; Thiemann, Thies; Al-Saadi, Abdulaziz A; Popoola, Saheed A; Van Alsenoy, C; Al Jasem, Yosef

    2015-11-01

    FT-IR and FT-Raman spectra of ethyl 3-(E)-(anthracen-9-yl)prop-2-enoate were recorded and analyzed. The conformational behavior of the molecule was also investigated. The vibrational wavenumbers were calculated using DFT quantum chemical calculations. The data obtained from the wavenumber calculations were used to assign vibrational bands obtained experimentally. The geometrical parameters are in agreement with XRD data. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The HOMO and LUMO analysis were used to determine the charge transfer within the molecule and quantum chemical parameters related to the title compound. From the MEP analysis, it is clear that the negative electrostatic potential regions are mainly localized over the carbonyl groups and anthracene ring and are possible sites for electrophilic attack and the positive regions are localized at all the hydrogen atoms as possible sites for nucleophilic attack. NLO and NMR studies are also reported. Molecular docking studies suggest that the title compound might exhibit inhibitory activity against IDE and may act as an insulysin inhibitor. Conformational analysis is also reported.

  10. A femtosecond study of the anomaly in electron injection for dye-sensitized solar cells: the influence of isomerization employing Ru(II) sensitizers with anthracene and phenanthrene ancillary ligands.

    PubMed

    Cheema, Hammad; Younts, Robert; Ogbose, Louis; Gautam, Bhoj; Gundogdu, Kenan; El-Shafei, Ahmed

    2015-01-28

    In this study, an intriguing difference caused by structural isomerization based on anthracene and phenanthrene stilbazole type ancillary ligands in Ru(ii) sensitizers for dye sensitized solar cells (DSCs) has been investigated using femtosecond transient absorption spectroscopy. Both anthracene and phenanthrene based sensitizers HD-7 and HD-8, respectively, resulted in a similar extinction coefficient, photophysical and thermodynamic free energy of electron injection and dye regeneration as measured by UV-Vis, excited state lifetime and cyclic voltammetry measurements, respectively. However, TiO2 adsorbed HD-7 resulted in up to 45% less photocurrent density than HD-8 although photovoltage was similar owing to comparable thermodynamic characteristics. It was obvious from the measurement of incident photon to current conversion efficiency (IPCE) that excited electrons in HD-7 are prone to internal energy loss before injection into the TiO2 conduction band. Analysis of photo-induced spectral features measured by femtosecond transient absorption spectroscopy showed that excited electrons in HD-7 are prone to ISC (intersystem crossing) much more than HD-8 and those triplet electrons are not injected into TiO2 efficiently. Interestingly, from impedance measurements, HD-7 showed higher recombination resistance than HD-8 and N719, but a shorter lifetime for electrons injected into the TiO2 conduction band.

  11. Organ specific, protocol dependent modulation of 7,12-dimethylbenz[a]anthracene carcinogenesis in rainbow trout (Oncorhynchus mykiss) by dietary ellagic acid.

    PubMed

    Harttig, U; Hendricks, J D; Stoner, G D; Bailey, G S

    1996-11-01

    This study investigated pre-initiation and post-initiation effects of dietary ellagic acid (EA) on 7,12-dimethylbenz[a]anthracene (DMBA) multi-organ carcinogenesis in rainbow trout (Oncorhynchus mykiss). EA at 100, 250 (study 2), 1000 and 2000 (study 1) p.p.m. suppressed stomach adenopapilloma incidence by 33, 60, 70 and 78% (P < or = 0.001), respectively, as well as tumor multiplicity (P < 0.01) and size (P < 0.001) when fed continuously following DMBA initiation. However, continuous EA feeding also produced modest (250 p.p.m.) to extensive (1000, 2000 p.p.m.) growth rate suppression in these studies. Retrospective logistic regression modeling of the data allowed separation of growth-related from non-growth-related inhibitory effects. By this approach: (i) tumor development showed a similarly strong dependence (same regression slope) on animal growth rate in all treatment groups; (ii) EA-mediated reduction in mean population growth contributed to suppressed stomach tumor response above 250 p.p.m. EA; and (iii) even at high, toxic doses EA displayed inhibitory mechanisms additional to, and distinct from, growth suppression effect. The effects of post-initiation EA were organ specific. Chronic EA treatment significantly suppressed swim-bladder as well as stomach tumor incidence at doses > or = 1000 p.p.m., but increased liver tumor incidence at doses > or = 250 p.p.m. Three protocols examined EA effects on the initiation process. EA fed at 1000 p.p.m. concurrently with 750 p.p.m. dietary DMBA for 7 weeks modestly reduced stomach tumor incidence (from 85 to 78%, P < 0.05) and multiplicity (from 6.3 +/- 4.3 to 4.9 +/- 2.9, P < 0.01), but did not alter swim-bladder or liver response. The effect of EA pretreatment prior to DMBA single-dose initiation by gill uptake was also examined. When fed for 1 week prior to initiation, 2000 p.p.m. EA again imposed a small reduction in stomach adenoma incidence (from 88 to 78%; P < 0.05) and multiplicity (from 5.5 +/- 3.2 to 4

  12. Gas-phase intramolecular Diels-Alder reactions of 2,3-dimethylene-2,3-dihydrofurans. II. Formation of anthracene and other polycyclic aromatic compounds in the pyrolysis of 1,5-bidenzocyclooctadienes and related compounds. III. Formation of 9-methylanthracene and anthracene in the pyrolysis of 5,6,11,12-tetrahydrodibenzo(A,E)cyclooctene and other related compounds. IV. Preparation of cyclopentadienones by flash vacuum pyrolysis and their dimerization and intramolecular reactions

    SciTech Connect

    Lee, S.K.

    1987-01-01

    The intramolecular Diels-Alder reactions of 2,3-dimethylene-2,3-dihydrofurans have been investigated through the pyrolysis of 2-alkenyl-3-furylmethyl benzoates. Under flash vacuum pyrolysis (FVP) conditions each of the 2,3-dimethylene-2,3-dihydrofurans can undergo an intramolecular Diels-Alder reaction or 1,5-hydrogen shift to give the corresponding tricycles 4c,t, 5c,t, and 6c,t and 1,5-hydrogen shift products 36c,t and 37c,t. FVP of 1,5-dibenzocyclooctadienes containing heteroatoms and dibenzosuberanes gave the corresponding tricyclic compounds (benzodifuran (18), acridine (24), and anthracene) with exception of 6H, 11H-dibenzo(b,f)(1,4)-dioxocin (17). The FVP of 17 gave (2-hydroxybenzyl)-o-benzaldehyde (28) as a major product. A mechanistic study of the regiospecific formation of 9-methyl-anthracene from the sealed tube pyrolysis the (4 + 4) dimer of o-xylylene (1) is presented. This study was carried out by pyrolyzing several possible precursors for 9-methylanthracene (e.g., 5,6-dihydrodibenzo(a,e)cyclooctene, di-o-tolylethane, and 5-methyldibenzosuberane). Sealed tube pyrolyses of dibenzosuberanes and dibenzosuberones were also carried out. A new method of preparing cyclopentadienones by the pyrolysis of cyclic diethers is presented. Cyclopentadienones including inden-2-one have been utilized in the synthesis of polycyclic compounds. The transient existence of these intermediates has also been proven by the isolation of polycyclic compounds.

  13. Synthesis and characterization of vinylimidazolium salts: Solution state study to realize the influence of different anions

    NASA Astrophysics Data System (ADS)

    Suresh, Paladugu; Samanta, Arpan; Sathyanarayana, Arruri; Prabusankar, Ganesan

    2012-09-01

    New vinylimidazolium salts, [9,10-bis{(N-vinylimidazolium)methyl}anthracene] bistetrafluoroborate (2) and [9,10-bis{(N-vinylimidazolium)methyl}anthracene] bishexafluorophosphate (3) have been prepared by the N alkylation of 9,10-bis(chloromethyl)anthracene with 1-vinylimidazole in 1,4-dioxane at 70 °C followed by the anion exchange reaction between [9,10-bis{(N-vinylimidazolium)methyl}anthracene] dichloride (1) and ammonium salt of tetrafluoroborate (for 2) or hexafluorophosphate (for 3). The interaction of tribromide anion with 1-3 has been studied with the help of 1H NMR and fluorescence spectra. Notably, the tribromide anion exhibits very strong fluorescent quenching effects towards 2 than 1 and 3. Similarly, 2 shows very strong fluorescent quenching effect in the presence of tribromide anion compare to bromide anion. Moreover the proton of imidazolium cation, Nsbnd CHsbnd N in 2 undergoes considerable downfield shift in the presence of tribromide anion, while the vinyl group depicts strong upfield shift due to the possible interaction of tribromide with vinylimidazolium unit.

  14. Anion-exchange and anthracene-encapsulation within copper(II) and manganese(II)-triazole metal-organic confined space in a single crystal-to-single crystal transformation fashion.

    PubMed

    Liu, Ju-Yan; Wang, Qian; Zhang, Li-Jun; Yuan, Bin; Xu, Yao-Yao; Zhang, Xin; Zhao, Cong-Ying; Wang, Dan; Yuan, Yue; Wang, Ying; Ding, Bin; Zhao, Xiao-Jun; Yue, Min Min

    2014-06-16

    A new multidentate ligand 1-(9-(1H-1,2,4-triazol-1-yl)anthracen-10-yl)-1H-1,2,4-triazole (tatrz) was designed and synthesized. Using tatrz as a building block, three novel coordination frameworks, namely, {[Cu(tatrz)2(NO3)2]·(CH3OH)·4H2O}n (1), {[Cu(tatrz)2(H2O)2](BF4)2}n (2), and [Mn(tatrz)2(SCN)2(CH3OH)]·2H2O (3) can be isolated. Anion-exchange experiment indicates that NO3(-) anions in the two-dimensional (2D) copper framework of 1 can be completely exchanged by ClO4(-) in an irreversible single crystal-to-single crystal (SC-SC) transformation fashion, as evidenced by the anion-exchange products of {[Cu(tatrz)2(H2O)2](ClO4)2·4CH3OH} (1a). Further, if 1a was employed as a precursor in N,N-dimethylformamide (DMF), an isomorphic solvate of {[Cu(tatrz)2(DMF)2](ClO4)2·2H2O}n (1b) can be generated during the reversible dynamic transformation process. When 1 was immersed in CH3OH, a distinct 2D layer {[Cu(tatrz)2(NO3)2]·4.4CH3OH·0.6H2O}n (1c) was isolated. Interestingly, the solvent-exchange conversion is also invertible between 1 and 1c, which exhibits spongelike dynamic behavior with retention of crystalline integrity. If the 2-fold interpenetrating three-dimensional (3D) framework 2 is selected, it can be transformed into another 2-fold interpenetrating 3D framework {[Cu(tatrz)2(H2O)2](ClO4)2·5.56H2O}n (2a) in a reversible SC-SC transformation fashion. However, when the light yellow crystals of mononuclear complex 3 were exposed to trichloromethane containing aromatic organic anthracene (atan), through our careful observation, the crystals of 3 were dissolved and reassembled into dark brown crystals of 2D crystalline coordination framework {[Mn(tatrz)2(SCN)2]·(atan)}n (3a). X-ray diffraction revealed that in 3a, atan acting as an organic template was encapsulated in the confined space of the 2D grid. Luminescent measurements illustrate that 3a is the first report of multidimensional polymers based on triazole derivatives as luminescent probes of Mg(2+).

  15. Combinatorial chemopreventive effect of butyric acid, nicotinamide and calcium glucarate against the 7,12-dimethylbenz(a)anthracene induced mouse skin tumorigenesis attained by enhancing the induction of intrinsic apoptotic events.

    PubMed

    Tiwari, Prakash; Sahay, Satya; Pandey, Manuraj; Qadri, Syed S Y H; Gupta, Krishna P

    2015-01-25

    We explored the basis of the combinatorial chemopreventive effect of butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG) on mouse skin exposed to 7,12-dimethylbenz(a)anthracene (DMBA). We studied the effects of topical application of DMBA in the presence or absence of BA, NA and CAG on the regulators of apoptosis. DMBA treatment suppressed Bax, Bax/Bcl-2 ratio, release of cyt c, Apaf1, caspase-9, -3 mediated apoptosis. Downregulation of p21 and upregulation of Bcl-2, mut p53 were also observed in only DMBA treated mice. Simultaneous application of BA, NA and CAG induced a mitochondria-mediated apoptosis, characterized by a rise in the Bax, Bax/Bcl-2 ratio, release of cyt c, upregulation of Apaf1 with down-stream activation of caspase-9, -3. Furthermore treatment with BA, NA and CAG demonstrated an upregulation of p21 and downregulation of Bcl-2, mut p53. But this effect was enhanced in the presence of all the three compounds together in combination. Chemoprevention by a combination of BA, NA and CAG by inducing the apoptosis, the natural cell death, suggest the importance of the potential combinational strategies capable of preventing skin tumor development.

  16. Synthesis of 1,4-anthracene-9,10-dione derivatives and their regulation of nitric oxide, IL-1β and TNF-α in activated RAW264.7 cells.

    PubMed

    Corrêa, Taís Arthur; Alves, Caio C S; Castro, Sandra B R; Oliveira, Erick E; Franco, Lucas S; Ferreira, Ana P; de Almeida, Mauro V

    2013-10-01

    Mitoxantrone is an anthracenedione antineoplastic and immunosuppressive agent approved for multiple sclerosis treatment. Novel mono- and disubstituted anthraquinone derivatives, analogues of mitoxantrone, were synthesized through the addition of lipophilic amino alcohols and evaluated for their effect on IL-1β, TNF-α and nitric oxide production by LPS/IFN-γ-stimulated RAW264.7 cells. The disubstituted 1,4-anthracene-9,10-dione 10 showed significant inhibition of nitric oxide, TNF-α and IL-1β production at the concentration of 5 μg/mL, with a much lower cytotoxicity than mitoxantrone. The monosubstituted 3, 4, 11, 12 and 13 also displayed a moderate to good inhibitory capacity on IL-1β production. However, the methylated compounds 11, 12 and 13 failed to inhibit the TNF-α production, and compound 13 was the only one to decrease the production of nitric oxide. None of these derivatives was toxic at the tested concentrations. Compounds 10 and 13 had better inhibitory capacity of the inflammatory mediators analyzed, with reliable viability of the cells.

  17. Synthesis and antitumor evaluations of symmetrically and unsymmetrically substituted 1,4-bis[(aminoalkyl)amino]anthracene-9,10-diones and 1,4-bis[(aminoalkyl)amino]-5,8-dihydroxyanthracene-9,10-diones.

    PubMed

    Krapcho, A P; Getahun, Z; Avery, K L; Vargas, K J; Hacker, M P; Spinelli, S; Pezzoni, G; Manzotti, C

    1991-08-01

    The ipso bis displacements of fluoride from 1,4-difluoroanthracene-9,10-dione (3) and 1,4-difluoro-5,8-dihydroxyanthracene-9,10-dione (4) by excess of a diamine (or a monoamine) in pyridine at room temperature lead to the symmetrically substituted 1,4-bis-substituted analogues 5 and 6, respectively. The ipso monodisplacements of fluoride from 3 and 4 can be accomplished by treatment with less than 1 molar equiv of a diamine (or a monoamine) to yield 7 and 8, respectively. Treatment of 7 or 8 with a different diamine leads to the unsymmetrically substituted 1,4-bis[(aminoalkyl)amino]anthracene-9,10-diones 9 and 10, respectively. Many of the synthetic unsymmetrical analogues have been evaluated for their antitumor activity against L1210 in vitro and in vivo. Cross resistance of analogue 10a with mitoxantrone (2) and doxorubicin was evaluated against MDR lines in vitro against human colon carcinoma LOVO and its subline resistant to DOXO (LOVO/DOXO). Potential mechanisms for the observed cytotoxicity are presented and discussed.

  18. Crystal structure of 2-[(3S,4S)-4-(anthracen-9-yl)-1-(4-meth­oxy­phen­yl)-2-oxoazetidin-3-yl]-2-aza-2H-phenalene-1,3-dione unknown solvate

    PubMed Central

    Çelik, Ísmail; Akkurt, Mehmet; Jarrahpour, Aliasghar; Rad, Javad Ameri; Çelik, Ömer

    2015-01-01

    The central β-lactam ring of the title compound, C36H24N2O4, is almost planar (r.m.s. deviation = 0.003 Å) and makes dihedral angles of 17.17 (19), 89.76 (17) and 78.44 (17)° with the benzene ring, the anthracene ring (r.m.s. deviation = 0.003 Å) and the 1H-benzo[de]iso­quinoline-1,3(2H)-dione moiety, which is nearly planar [maximum deviation = 0.098 (2) Å], respectively. The mol­ecular structure is stabilized by an intra­molecular C—H⋯N hydrogen bond. In the crystal, mol­ecules are linked via C—H⋯π and π–π stacking inter­actions [centroid–centroid distances = 3.5270 (19) and 3.779 (2) Å], forming a three-dimensional structure. A region of disordered electron density, probably disordered solvent mol­ecules, was treated with the SQUEEZE procedure in PLATON [Spek (2015 ▸). Acta Cryst. C71, 9–18], which indicated a solvent cavity of 322 Å3 containing approximately 91 electrons. Their formula mass and unit-cell characteristics were not taken into account during the refinement. PMID:25844239

  19. Modulation of miR-203 and its regulators as a function of time during the development of 7, 12 dimethylbenz [a] anthracene induced mouse skin tumors in presence or absence of the antitumor agents.

    PubMed

    Tiwari, Prakash; Gupta, Krishna P

    2014-07-15

    We investigated the chemopreventive effects of naturally occurring compounds like butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG) individually or in combination in 7, 12-dimethylbenz [a] anthracene (DMBA) treated mouse skin at 4 and 16 weeks, the time before and after the tumor development. DMBA application did not show any skin tumors at 4 weeks but well defined tumors appeared at 16 weeks. BA, NA or CAG prevented the tumor development significantly but the protection was highly enhanced when all these compounds were given together. In order to see the molecular changes progressing with tumors, we showed the downregulation of tumor suppressor miR-203 at 16 weeks and upregulation of histone deacetylases (HDAC), DNA methyltransferase, promoter methylation of miR-203 at 4 or 16 weeks. Regulators of micro RNA biogenesis such as DICER1 and Ago2 were also deregulated by DMBA. Proto-oncogene c-myc and BMI1 were upregulated and tumor suppressor gene p16 was downregulated by DMBA as a function of time. Effects of BA, NA or CAG were more pronounced after 16 weeks as compared to 4 weeks in preventing the tumor development and altered gene expression. Concomitant administration of BA, NA and CAG tried to prevent these alterations more effectively than that of individual compound possibly by regulating miR-203 status through epigenetic or biogenetic modulations before and after the tumor development. Study provides a rationale for chemoprevention by combination of different compounds targeting miR-203. PMID:24792773

  20. Combinatorial chemopreventive effect of butyric acid, nicotinamide and calcium glucarate against the 7,12-dimethylbenz(a)anthracene induced mouse skin tumorigenesis attained by enhancing the induction of intrinsic apoptotic events.

    PubMed

    Tiwari, Prakash; Sahay, Satya; Pandey, Manuraj; Qadri, Syed S Y H; Gupta, Krishna P

    2015-01-25

    We explored the basis of the combinatorial chemopreventive effect of butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG) on mouse skin exposed to 7,12-dimethylbenz(a)anthracene (DMBA). We studied the effects of topical application of DMBA in the presence or absence of BA, NA and CAG on the regulators of apoptosis. DMBA treatment suppressed Bax, Bax/Bcl-2 ratio, release of cyt c, Apaf1, caspase-9, -3 mediated apoptosis. Downregulation of p21 and upregulation of Bcl-2, mut p53 were also observed in only DMBA treated mice. Simultaneous application of BA, NA and CAG induced a mitochondria-mediated apoptosis, characterized by a rise in the Bax, Bax/Bcl-2 ratio, release of cyt c, upregulation of Apaf1 with down-stream activation of caspase-9, -3. Furthermore treatment with BA, NA and CAG demonstrated an upregulation of p21 and downregulation of Bcl-2, mut p53. But this effect was enhanced in the presence of all the three compounds together in combination. Chemoprevention by a combination of BA, NA and CAG by inducing the apoptosis, the natural cell death, suggest the importance of the potential combinational strategies capable of preventing skin tumor development. PMID:25478867

  1. Interactions between 7, 12-dimethylbenz(a)anthracene (DMBA) and repeated low-level X radiation in hamster cheek pouch carcinogenesis: dependence on the relative timing of DMBA and radiation treatments

    SciTech Connect

    Lurie, A.G.

    1982-04-01

    Low-level X radiation was shown to enhance Syrian hamster cheek pouch carcinogenesis by 7,12-dimethylbenz(a)anthracene (DMBA) when radiation was administered concurrently with and following DMBA applications. We studied the effects of altering the timing of radiation and DMBA applications on this enhancement. DMBA in mineral oil was applied twice weekly for 10 weeks and 20 R head and neck X radiation once weekly for 17 weeks. In duplicate studies, animals received radiation, DMBA, or DMBA plus X radiation. In the DMBA plus X-ray group, there were 9 weeks of preirradiation and 7 weeks of concurrent treatments. Radiation alone did not result in any histologically detectable changes. In one study, preirradiation may have reduced the carcinogenic activity of DMBA, while in the second study there were no significant differences in tumor incidences between X radiation plus DMBA and DMBA only groups. Thus, while repeated 20-R-X-ray exposures during the following DMBA applications enhance DMBA carcinogenesis, identical X-ray exposures prior to and during DMBA applications appear either to slightly inhibit or to have no appreciable effect on DMBA carcinogenesis.

  2. Differential carcinogenic effects of intraperitoneal initiation with 7,12-dimethylbenz(a)anthracene or urethane and topical promotion with 12-O-tetradecanoylphorbol-13-acetate in skin and internal tissues of female SENCAR and BALB/c mice

    SciTech Connect

    Ward, J.M.; Rehm, S.; Devor, D.; Hennings, H.; Wenk, M.L.

    1986-09-01

    Groups of female SENCAR or BALB/c mice were initiated once intraperitoneally with 300 ..mu..g/mouse of 7,12-dimethylbenz(a) anthracene (DMBA) or 20 mg/mouse of urethane at 7 weeks of age. Beginning one week later, mice received topically applied acetone or 12-O-tetradecanoylphorbol-13-acetate (TPA), once weekly, at 2.5 ..mu..g/mouse for weeks 1 through 6 and 1.25 ..mu..g/mouse for weeks 7 through 52. The skin lesions were evaluated clinically. A complete necropsy was performed on all mice at week 52. SENCAR mice exposed to DMBA/TPA and urethane/TPA had more skin tumors than SENCAR mice exposed to DMBA or urethane alone and more than BALB/c mice in any treatment group. Of all skin carcinomas diagnosed histologically in DMBA/TPA-exposed mice, less than one-third had been identified clinically while the mice were alive. Most of the carcinomas arose within papillomas. BALB/c mice developed more vascular and uterine tumors than did SENCAR mice injected with DMBA and more lung and vascular tumors than did SENCAR mice injected with urethane. TPA exposure after treatment with either initiator had no significant effect on internal tumor development in either SENCAR or BALB/c mice.

  3. Selection of carcinogen-altered rat tracheal epithelial cells preexposed to 7,12-dimethylbenz(a)anthracene by their loss of a need for pyruvate to survive in culture

    SciTech Connect

    Marchok, A.C.; Huang, S.F.; Martin, D.H.

    1984-01-01

    Normal rat tracheal epithelial cells require exogenous pyruvate to survive in culture while carcinogen-altered cells do not. The aims of our study were, (i) to utilize this loss of requirement for pyruvate by carcinogen-altered cells as a way of selecting out and quantitating the numbers of altered cell populations induced in tracheas exposed to 200 ..mu..g 7,12-dimethylbenz(a)-anthracene (DMBA)-beeswax pellets for different lengths of time, (ii) to determine the constancy of these numbers at increasing time intervals after the exposure, (iii) to look for distinctive growth properties in cell populations that may be related to the exposure conditions. Results show that there were 1.8/altered or selected cell populations (SPC) trachea 2 months after the 2 weeks exposure, while 5.0 and 7.2 SPC were obtained from the 4 weeks and continuously exposed tracheas, respectively, at this time. The numbers of SPC did not increase with time after exposure indicating that the maximal number of initiation sites was fixed. Between 2 and 9 months the number of subculturable SPC increased from 67 to 88% in the 2 week exposed group, while 93-100% of the SPC were subculturable after the longer DMBA exposures. Only the SPC from the 2 week DMBA-2 month group were distinguished by smaller numbers of cells surviving the selection medium and by a slower average growth rate compared to all the other experimental conditions. 29 references, 3 figures, 2 tables.

  4. Modulatory Effect of Taurine on 7,12-Dimethylbenz(a)Anthracene-Induced Alterations in Detoxification Enzyme System, Membrane Bound Enzymes, Glycoprotein Profile and Proliferative Cell Nuclear Antigen in Rat Breast Tissue.

    PubMed

    Vanitha, Manickam Kalappan; Baskaran, Kuppusamy; Periyasamy, Kuppusamy; Selvaraj, Sundaramoorthy; Ilakkia, Aruldoss; Saravanan, Dhiravidamani; Venkateswari, Ramachandran; Revathi Mani, Balasundaram; Anandakumar, Pandi; Sakthisekaran, Dhanapal

    2016-08-01

    The modulatory effect of taurine on 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast cancer in rats was studied. DMBA (25 mg/kg body weight) was administered to induce breast cancer in rats. Protein carbonyl levels, activities of membrane bound enzymes (Na(+) /K(+) ATPase, Ca(2+) ATPase, and Mg(2+) ATPase), phase I drug metabolizing enzymes (cytochrome P450, cytochrome b5, NADPH cytochrome c reductase), phase II drug metabolizing enzymes (glutathione-S-transferase and UDP-glucuronyl transferase), glycoprotein levels, and proliferative cell nuclear antigen (PCNA) were studied. DMBA-induced breast tumor bearing rats showed abnormal alterations in the levels of protein carbonyls, activities of membrane bound enzymes, drug metabolizing enzymes, glycoprotein levels, and PCNA protein expression levels. Taurine treatment (100 mg/kg body weight) appreciably counteracted all the above changes induced by DMBA. Histological examination of breast tissue further supported our biochemical findings. The results of the present study clearly demonstrated the chemotherapeutic effect of taurine in DMBA-induced breast cancer. PMID:27091720

  5. Crystal structure of 2-[(3S,4S)-4-(anthracen-9-yl)-1-(4-meth-oxy-phen-yl)-2-oxoazetidin-3-yl]-2-aza-2H-phenalene-1,3-dione unknown solvate.

    PubMed

    Çelik, Ísmail; Akkurt, Mehmet; Jarrahpour, Aliasghar; Rad, Javad Ameri; Çelik, Ömer

    2015-03-01

    The central β-lactam ring of the title compound, C36H24N2O4, is almost planar (r.m.s. deviation = 0.003 Å) and makes dihedral angles of 17.17 (19), 89.76 (17) and 78.44 (17)° with the benzene ring, the anthracene ring (r.m.s. deviation = 0.003 Å) and the 1H-benzo[de]iso-quinoline-1,3(2H)-dione moiety, which is nearly planar [maximum deviation = 0.098 (2) Å], respectively. The mol-ecular structure is stabilized by an intra-molecular C-H⋯N hydrogen bond. In the crystal, mol-ecules are linked via C-H⋯π and π-π stacking inter-actions [centroid-centroid distances = 3.5270 (19) and 3.779 (2) Å], forming a three-dimensional structure. A region of disordered electron density, probably disordered solvent mol-ecules, was treated with the SQUEEZE procedure in PLATON [Spek (2015 ▶). Acta Cryst. C71, 9-18], which indicated a solvent cavity of 322 Å(3) containing approximately 91 electrons. Their formula mass and unit-cell characteristics were not taken into account during the refinement. PMID:25844239

  6. Modulatory Effect of Taurine on 7,12-Dimethylbenz(a)Anthracene-Induced Alterations in Detoxification Enzyme System, Membrane Bound Enzymes, Glycoprotein Profile and Proliferative Cell Nuclear Antigen in Rat Breast Tissue.

    PubMed

    Vanitha, Manickam Kalappan; Baskaran, Kuppusamy; Periyasamy, Kuppusamy; Selvaraj, Sundaramoorthy; Ilakkia, Aruldoss; Saravanan, Dhiravidamani; Venkateswari, Ramachandran; Revathi Mani, Balasundaram; Anandakumar, Pandi; Sakthisekaran, Dhanapal

    2016-08-01

    The modulatory effect of taurine on 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast cancer in rats was studied. DMBA (25 mg/kg body weight) was administered to induce breast cancer in rats. Protein carbonyl levels, activities of membrane bound enzymes (Na(+) /K(+) ATPase, Ca(2+) ATPase, and Mg(2+) ATPase), phase I drug metabolizing enzymes (cytochrome P450, cytochrome b5, NADPH cytochrome c reductase), phase II drug metabolizing enzymes (glutathione-S-transferase and UDP-glucuronyl transferase), glycoprotein levels, and proliferative cell nuclear antigen (PCNA) were studied. DMBA-induced breast tumor bearing rats showed abnormal alterations in the levels of protein carbonyls, activities of membrane bound enzymes, drug metabolizing enzymes, glycoprotein levels, and PCNA protein expression levels. Taurine treatment (100 mg/kg body weight) appreciably counteracted all the above changes induced by DMBA. Histological examination of breast tissue further supported our biochemical findings. The results of the present study clearly demonstrated the chemotherapeutic effect of taurine in DMBA-induced breast cancer.

  7. Investigation of three-terminal organic-based devices with memory effect and negative differential resistance

    NASA Astrophysics Data System (ADS)

    Yu, Li-Zhen; Lee, Ching-Ting

    2009-09-01

    The current-voltage characteristics of the gate-controlled three-terminal organic-based devices with memory effect and negative differential resistances (NDR) were studied. Gold and 9,10-di(2-naphthyl)anthracene (ADN) were used as the metal electrode and active channel layer of the devices, respectively. By using various gate-source voltages, the memory and NDR characteristics of the devices can be modulated. The memory and NDR characteristics of the devices were attributed to the formation of trapping sites in the interface between Au electrode and ADN active layer caused by the defects, when Au metal deposited on the ADN active layer.

  8. A high performance fluorescent white organic light-emitting device and its optimization for full-colour display

    NASA Astrophysics Data System (ADS)

    Li, Jiang; Duan, Yu; Zhao, Yi; Li, Xinhong; Li, Chuannan; Hou, Jingying; Liu, Shiyong

    2006-02-01

    A white organic light emitting diode (OLED) was fabricated in which blue emission host 9,10-di(2-naphthyl)anthracene (ADN) doped with an orange emission dye (rubrene) was used to generate bright, high efficiency white light. A large amount of work was done to study the emission mechanism of a rubrene-doped device. Finally, to get optimized EL spectra, we introduced a green light which is emitted from tris(8-hydroxy-quinoline) aluminium (Alq3), the electron transport material, into the emission of white light.

  9. Retraction: erbB expression changes in ethanol and 7,12- dimethylbenz (a)anthracene-induced oral carcinogenesis. Med Oral Patol Oral Cir Bucal. 2013 Mar 1;18(2):e325-31.

    PubMed

    2014-01-01

    The authors (Garcia Carrancá A, Zentero Galindo E, Jiménez Farfán MD and Hernandez Guerrero JC) express that one of the figures of the original article (Jacinto-Alemán LF, García-Carrancá A, Leyba-Huerta ER, Zenteno-Galindo E, Jiménez-Farfán MD, Hernández-Guerrero JC. erbB expression changes in ethanol and 7,12- dimethylbenz (a)anthracene-induced oral carcinogenesis. Med Oral Patol Oral Cir Bucal. 2013 Mar 1;18(2):e325-31.) corresponding to Western blots have not been found and the voluntary alteration of this figure is evident. The coauthors Alejandro García Carranca, Edgar Zenteno Galindo, Maria Dolores Jiménez Farfán and Juan Carlos Hernández Guerrero have made the decision to take back what has been published, as they have come to the conclusion, that at least this result is false. The editor declare that the journal had the signed copyright by the authors when the article was initially published. This copyright document certifies that the undersigned authors warrants that the article is original; is not under consideration by another publication; and its tables or figures have not been previously published. The authors confirmed that the final article had been read and each author's contribution had been approved by the appropriate author. The editor has made the decision to retract the article due to the above comments of some authors against the rest. The editors apologize to the readers and reviewers of Med Oral Patol Oral Cir Bucal for the inconvenience caused by the authors of the article.

  10. Modulation of miR-203 and its regulators as a function of time during the development of 7, 12 dimethylbenz [a] anthracene induced mouse skin tumors in presence or absence of the antitumor agents

    SciTech Connect

    Tiwari, Prakash; Gupta, Krishna P.

    2014-07-15

    We investigated the chemopreventive effects of naturally occurring compounds like butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG) individually or in combination in 7, 12-dimethylbenz [a] anthracene (DMBA) treated mouse skin at 4 and 16 weeks, the time before and after the tumor development. DMBA application did not show any skin tumors at 4 weeks but well defined tumors appeared at 16 weeks. BA, NA or CAG prevented the tumor development significantly but the protection was highly enhanced when all these compounds were given together. In order to see the molecular changes progressing with tumors, we showed the downregulation of tumor suppressor miR-203 at 16 weeks and upregulation of histone deacetylases (HDAC), DNA methyltransferase, promoter methylation of miR-203 at 4 or 16 weeks. Regulators of micro RNA biogenesis such as DICER1 and Ago2 were also deregulated by DMBA. Proto-oncogene c-myc and BMI1 were upregulated and tumor suppressor gene p16 was downregulated by DMBA as a function of time. Effects of BA, NA or CAG were more pronounced after 16 weeks as compared to 4 weeks in preventing the tumor development and altered gene expression. Concomitant administration of BA, NA and CAG tried to prevent these alterations more effectively than that of individual compound possibly by regulating miR-203 status through epigenetic or biogenetic modulations before and after the tumor development. Study provides a rationale for chemoprevention by combination of different compounds targeting miR-203. - Highlights: • DMBA modulates miR-203 and its regulator before and after the onset of tumors. • Suppression of miR-203 and p16 could be the result of gene promoter methylation. • BA, NA or CAG prevents the effects of DMBA. • Combination of BA, NA or CAG is more effective in preventing the DMBA modulations.

  11. Preventive effects of butyric acid, nicotinamide, calcium glucarate alone or in combination during the 7, 12-dimethylbenz (a) anthracene induced mouse skin tumorigenesis via modulation of K-Ras-PI3K-AKTpathway and associated micro RNAs.

    PubMed

    Tiwari, Prakash; Sahay, Satya; Pandey, Manuraj; Qadri, Syed S Y H; Gupta, Krishna P

    2016-02-01

    Skin cancer is among the most common cancers worldwide and identifiable molecular changes for early and late stage of skin tumorigenesis can suggest the better targets for its control. In this study, we investigated the status of K-Ras-PI3K-AKTpathway followed by NF-κB, cyclin D1, MMP-9 and regulatory micro RNA during 7, 12-dimethylbenz[a]anthracene (DMBA) induced mouse skin tumorigenesis and its prevention by butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG), individually or in combination with respect to time. DMBA upregulated the K-Ras, PI3K, Akt, NF-κB, cyclin D1 and MMP-9, but downregulated the PTEN in a time dependent manner. DMBA also reduced the levels of micoRNA let-7a but induced the levels of miR-21 and miR-20a as a function of time. BA, NA and CAG were found to prevent DMBA induced changes, but they were most effective when used together in a combination. Reduced let-7a and miR-211 were correlated with the overexpression of K-Ras and MMP-9. Overexpression of miR-21 and miR-20a was correlated with the down regulation of PTEN and overexpression of Cyclin D1. Collectively, the enhanced chemopreventive potential of natural compound in combination via regulation of K-Ras-PI3K-AKTpathway along with regulatory micro RNAs provide a newer and effective mean for cancer management.

  12. Enrichment of maternal diet with conjugated linoleic acids influences desaturases activity and fatty acids profile in livers and hepatic microsomes of the offspring with 7,12-dimethylbenz[a]anthracene-induced mammary tumors.

    PubMed

    Białek, Agnieszka; Stawarska, Agnieszka; Tokarz, Andrzej; Czuba, Katarzyna; Konarska, Anna; Mazurkiewicz, Magdalena

    2014-01-01

    The aim of this study was to assess the influence of diet supplementation of pregnant and breast-feeding female Sprague-Dawley rats with conjugated linoleic acids (CLA) on the Δ6- and Δ5-desaturase activity in hepatic microsomes as well as on fatty acids profile and lipids peroxidation in liver and hepatic microsomes of the progeny with chemically induced mammary tumors. Rats were divided into two groups with different diet supplementation (vegetable oil (which did not contain CLA) or CLA). Their female offspring was divided within these groups into two subgroups: (1)--fed the same diet as mothers (K1 - oil, 01 - CLA), and (2)--fed the standard fodder (K2, O2). At 50th day of life, the progeny obtained carcinogenic agent (7,12-dimethylbenz[a]anthracene). Higher supply of CLA in diet of mothers resulted in lower susceptibility to chemically induced mammary tumors in their offspring (p = 0.0322). It also influenced the fatty acids profile in livers and in hepatic microsomes, especially polyunsaturated n3 and n6 fatty acids. CLA inhibited the activity of the desaturases, which confirmed that CLA can reduce the level of arachidonic acid directly, reducing linoleic acid content in membranes, or indirectly, through the regulation of its metabolism. We were unable to confirm or deny the antioxidative properties of CLA. Our results indicate that the higher supply of CLA in mothers' diet during pregnancy and breastfeeding causes their incorporation into tissues of children, changes the efficiency of fatty acids metabolism and exerts health-promoting effect in their adult life reducing the breast cancer risk.

  13. Chemoprevention of 7,12-dimethylbenz[a]anthracene (DMBA)-induced oral carcinogenesis in hamster cheek pouch by topical application of a dual inhibitor of epidermal growth factor receptor (EGFR) and ErbB2 tyrosine kinases.

    PubMed

    Sun, Zheng; Sood, Sandeep; Li, Ning; Yang, Peiying; Newman, Robert A; Yang, Chung S; Chen, Xiaoxin

    2008-07-01

    Oral cancer is a common neoplasm worldwide with tobacco and alcohol being the major etiological factors contributing to its pathogenesis. Epidermal growth factor receptor (EGFR) and ErbB2 are known to be involved in the development of oral cancer with the former up-regulated in up to 90% human cases. The goal of this study was to evaluate the chemopreventive effects of a dual inhibitor of EGFR and ErbB2 tyrosine kinases, GW2974, in the 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster cheek pouch model. A short-term experiment (3-week topical DMBA followed by 1-week topical GW2974) was conducted to examine the effects of GW2974 on aberrant arachidonic acid (AA) metabolism and cell proliferation in the hamster oral epithelium. Topical application of 0.1 ml GW2974 (160 microM, three times a week) significantly reduced the levels of prostaglandin E2 (PGE2), leukotriene B4 (LTB4), 5-, 12-, 15-hydroxyeicosatetraenoic acid (HETE), and cell proliferation (BrdU-labeling index). In a long-term post-initiation experiment (6-week topical DMBA followed by 18-week topical GW2974), GW2974 (4 mM and 8 mM) significantly inhibited the incidence, number and size of visible tumors. Under microscope, the numbers of oral lesions (hyperplasia, dysplasia, carcinoma) and the incidence of squamous cell carcinoma (SCC) were also significantly suppressed by GW2974. In summary, our study indicated that dual inhibition of EGFR and ErbB2 tyrosine kinases by GW2974 was effective in preventing oral carcinogenesis in DMBA-induced hamster cheek pouch model. GW2974 exerted its chemopreventive effects in part by suppressing aberrant AA metabolism. PMID:17936675

  14. The effect of Plantago major Linnaeus on serum total sialic acid, lipid-bound sialic acid, some trace elements and minerals after administration of 7,12-dimethylbenz(a)anthracene in rats.

    PubMed

    Oto, Gokhan; Ekin, Suat; Ozdemir, Hulya; Levent, Abdulkadir; Berber, Ismet

    2012-05-01

    The present study was designed to evaluate the effect of Plantago major Linnaeus (PM) extract on serum total sialic acid (TSA), lipid-bound sialic acid (LSA), some trace elements (copper (Cu), zinc (Zn) and iron) and mineral levels (magnesium, calcium and sodium) in Wistar albino rat administrated 7,12-dimethylbenz(a)anthracene (DMBA). Rats were divided into three equal groups (n = 6). Group I comprised the control group, group II was treated with DMBA (100 mg/kg, single dose) and group III was treated with DMBA (100 mg/kg single dose) and aqueous extract of PM 100 mg/kg/day for 60 days. After 60 days, statistical analyses showed that TSA and LSA levels in DMBA and DMBA + PM groups were significantly higher compared to the control group (TSA: p < 0.01, p < 0.05; LSA: p < 0.05, p < 0.05, respectively). Serum Zn levels were decreased in subjects treated with DMBA (p < 0.01) and DMBA + PM (p < 0.05) compared to the control group values. Serum Cu levels were increased in DMBA group and PM-treated group compared to the control group values. The results of this investigation showed that the levels of TSA and LSA changed significantly, which are sensitive markers for detecting the toxic effects of DMBA. On the other hand, observed decline in Zn levels in rats from DMBA + PM group might be due to decreased generation of free radicals and oxidative stress. Results from this study suggest that PM may be partially effective in preventing carcinogenesis initiated by environmental carcinogen DMBA.

  15. Preventive effects of butyric acid, nicotinamide, calcium glucarate alone or in combination during the 7, 12-dimethylbenz (a) anthracene induced mouse skin tumorigenesis via modulation of K-Ras-PI3K-AKTpathway and associated micro RNAs.

    PubMed

    Tiwari, Prakash; Sahay, Satya; Pandey, Manuraj; Qadri, Syed S Y H; Gupta, Krishna P

    2016-02-01

    Skin cancer is among the most common cancers worldwide and identifiable molecular changes for early and late stage of skin tumorigenesis can suggest the better targets for its control. In this study, we investigated the status of K-Ras-PI3K-AKTpathway followed by NF-κB, cyclin D1, MMP-9 and regulatory micro RNA during 7, 12-dimethylbenz[a]anthracene (DMBA) induced mouse skin tumorigenesis and its prevention by butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG), individually or in combination with respect to time. DMBA upregulated the K-Ras, PI3K, Akt, NF-κB, cyclin D1 and MMP-9, but downregulated the PTEN in a time dependent manner. DMBA also reduced the levels of micoRNA let-7a but induced the levels of miR-21 and miR-20a as a function of time. BA, NA and CAG were found to prevent DMBA induced changes, but they were most effective when used together in a combination. Reduced let-7a and miR-211 were correlated with the overexpression of K-Ras and MMP-9. Overexpression of miR-21 and miR-20a was correlated with the down regulation of PTEN and overexpression of Cyclin D1. Collectively, the enhanced chemopreventive potential of natural compound in combination via regulation of K-Ras-PI3K-AKTpathway along with regulatory micro RNAs provide a newer and effective mean for cancer management. PMID:26655363

  16. Endogenous estrogen status, but not genistein supplementation, modulates 7,12-dimethylbenz[a]anthracene-induced mutation in the liver cII gene of transgenic big blue rats.

    PubMed

    Chen, Tao; Hutts, Robert C; Mei, Nan; Liu, Xiaoli; Bishop, Michelle E; Shelton, Sharon; Manjanatha, Mugimane G; Aidoo, Anane

    2005-06-01

    A growing number of studies suggest that isoflavones found in soybeans have estrogenic activity and may safely alleviate the symptoms of menopause. One of these isoflavones, genistein, is commonly used by postmenopausal women as an alternative to hormone replacement therapy. Although sex hormones have been implicated as an important risk factor for the development of hepatocellular carcinoma, there are limited data on the potential effects of the estrogens, including phytoestrogens, on chemical mutagenesis in liver. Because of the association between mutation induction and the carcinogenesis process, we investigated whether endogenous estrogen and supplemental genistein affect 7,12-dimethylbenz[a]anthracene (DMBA)-induced mutagenesis in rat liver. Intact and ovariectomized female Big Blue rats were treated with 80 mg DMBA/kg body weight. Some of the rats also received a supplement of 1,000 ppm genistein. Sixteen weeks after the carcinogen treatment, the rats were sacrificed, their livers were removed, and mutant frequencies (MFs) and types of mutations were determined in the liver cII gene. DMBA significantly increased the MFs in liver for both the intact and ovariectomized rats. While there was no significant difference in MF between the ovariectomized and intact control animals, the mutation induction by DMBA in the ovariectomized groups was significantly higher than that in the intact groups. Dietary genistein did not alter these responses. Molecular analysis of the mutants showed that DMBA induced chemical-specific types of mutations in the liver cII gene. These results suggest that endogenous ovarian hormones have an inhibitory effect on liver mutagenesis by DMBA, whereas dietary genistein does not modulate spontaneous or DMBA-induced mutagenesis in either intact or ovariectomized rats.

  17. A Comparative Account of the Kinetics of Light-Induced E-Z Isomerization of an Anthracene-Based Organogelator in Sol, Gel, Xerogel, and Powder States: Fiber to Crystal Transformation.

    PubMed

    Mondal, Sanjoy; Chakraborty, Priyadarshi; Das, Sujoy; Bairi, Partha; Nandi, Arun K

    2016-05-31

    The organogel of (E)-N'-(anthracene-10-ylmethylene)-3,4,5-tris(dodecyloxy)benzohydrazide (I) in methyl cyclohexane having a fibrillar network structure exhibits excellent fluorescence, which decreases sharply with time upon photoirradiation at λ = 365 nm. It has been attributed to the transformation of the E isomer of I to the Z isomer, and the kinetics of E-Z isomerization are compared for the sol, gel, xerogel, and powder states. The rate constants at different temperatures are measured from Avrami plots and its increase with an increase in temperature, indicating temperature acts as a promoter for photoirradiated E-Z isomeization along the imine (C═N) bond. In the powder form, the rate constant values are the lowest compared to those of other states for all temperatures and the xerogels exhibit the highest rate of E-Z isomerization. The rate constants of sol and gel states mostly lie between the two. The wide-angle X-ray scattering pattern changes after ultraviolet (UV) irradiation with the generation of new sharp peaks whose intensities increase with an increase in irradiation time. A polarized optical microscopic study indicates formation of small crystalline dots on the fibers in the gels, dendritic morphology on the xerogel fibers, and large needlelike morphology at the surface boundary of the solid. The dried I gel exhibits a melting peak at 96.7 °C, but upon irradiation, two peaks are observed at 98.5 and 152.7 °C; the latter has been attributed to the melting of crystals of Z isomers. Similar higher melting peaks are observed both for the xerogel and for powders after UV irradiation; the powders exhibit the highest meting peak at 159.4 °C. Possible reasons for the variation of rate constant values in the four different states and the difference in morphology and melting points of crystals of Z isomers of I are discussed.

  18. The effect of Plantago major Linnaeus on serum total sialic acid, lipid-bound sialic acid, some trace elements and minerals after administration of 7,12-dimethylbenz(a)anthracene in rats.

    PubMed

    Oto, Gokhan; Ekin, Suat; Ozdemir, Hulya; Levent, Abdulkadir; Berber, Ismet

    2012-05-01

    The present study was designed to evaluate the effect of Plantago major Linnaeus (PM) extract on serum total sialic acid (TSA), lipid-bound sialic acid (LSA), some trace elements (copper (Cu), zinc (Zn) and iron) and mineral levels (magnesium, calcium and sodium) in Wistar albino rat administrated 7,12-dimethylbenz(a)anthracene (DMBA). Rats were divided into three equal groups (n = 6). Group I comprised the control group, group II was treated with DMBA (100 mg/kg, single dose) and group III was treated with DMBA (100 mg/kg single dose) and aqueous extract of PM 100 mg/kg/day for 60 days. After 60 days, statistical analyses showed that TSA and LSA levels in DMBA and DMBA + PM groups were significantly higher compared to the control group (TSA: p < 0.01, p < 0.05; LSA: p < 0.05, p < 0.05, respectively). Serum Zn levels were decreased in subjects treated with DMBA (p < 0.01) and DMBA + PM (p < 0.05) compared to the control group values. Serum Cu levels were increased in DMBA group and PM-treated group compared to the control group values. The results of this investigation showed that the levels of TSA and LSA changed significantly, which are sensitive markers for detecting the toxic effects of DMBA. On the other hand, observed decline in Zn levels in rats from DMBA + PM group might be due to decreased generation of free radicals and oxidative stress. Results from this study suggest that PM may be partially effective in preventing carcinogenesis initiated by environmental carcinogen DMBA. PMID:21996710

  19. Blueberry inhibits invasion and angiogenesis in 7,12-dimethylbenz[a]anthracene (DMBA)-induced oral squamous cell carcinogenesis in hamsters via suppression of TGF-β and NF-κB signaling pathways.

    PubMed

    Baba, Abdul Basit; Kowshik, Jaganathan; Krishnaraj, Jayaraman; Sophia, Josephraj; Dixit, Madhulika; Nagini, Siddavaram

    2016-09-01

    Aberrant activation of oncogenic signaling pathways plays a pivotal role in tumor initiation and progression. The purpose of the present study was to investigate the chemopreventive and therapeutic efficacy of blueberry in the hamster buccal pouch (HBP) carcinogenesis model based on its ability to target TGF-β, PI3K/Akt, MAPK and NF-κB signaling and its impact on invasion and angiogenesis. Squamous cell carcinomas were induced in the HBP by 7,12-dimethylbenz[a]anthracene (DMBA). The effect of blueberry on the oncogenic signaling pathways and downstream events was analyzed by quantitative real-time PCR and immunoblotting. Experiments with the ECV304 cell line were performed to explore the mechanism by which blueberry regulates angiogenesis. Blueberry supplementation inhibited the development and progression of HBP carcinomas by abrogating TGF-β and PI3K/Akt pathways. Although blueberry failed to influence MAPK, it suppressed NF-κB activation by preventing nuclear translocation of NF-κB p65. Blueberry also modulated the expression of the oncomiR miR-21 and the tumor suppressor let-7. Collectively, these changes induced a shift to an anti-invasive and anti-angiogenic phenotype as evidenced by downregulating matrix metalloproteinases and vascular endothelial growth factor. Blueberry also inhibited angiogenesis in ECV304 cells by suppressing migration and tube formation. The results of the present study suggest that targeting oncogenic signaling pathways that influence acquisition of cancer hallmarks is an effective strategy for chemointervention. Identification of modulatory effects on phosphorylation, intracellular localization of oncogenic transcription factors and microRNAs unraveled by the present study as key mechanisms of action of blueberry is critical from a therapeutic perspective. PMID:27371785

  20. Epidermal changes following application of 7,12-dimethylbenz(a)anthracene and 12-O-tetradecanoylphorbol-13-acetate to human skin transplanted to nude mice studied with histological species markers

    SciTech Connect

    Graem, N.

    1986-01-01

    Effects of the tumor initiator 7,12-dimethylbenz(a)anthracene (DMBA) and of the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) on epidermis of human fetal and adult skin were studied in the nude mouse/human skin model. Human skin grafts on NC nude mice were exposed to two topical applications of 1 mg of DMBA in 50 microliter of acetone with an interval of 3 days and/or to applications of 10 micrograms of TPA in 50 microliter of acetone twice weekly. In some animals, it was attempted to augment the susceptibility of the grafts to the tumor-initiating effect of DMBA by pretreatment with TPA or ultraviolet light. The mice were sacrificed 8-32 wk after the initial treatment. Tumors did not appear in the central portions of any of the grafts, but epidermal tumors were seen at the graft border in 34.9% of the DMBA-treated animals. To identify human epidermis on the grafts and to determine the species origin of the induced tumors, two independently working histological marker methods were applied. (a) The first is detection of a human Blood Group B-like antigen present in mouse epidermis and in chemically induced murine epidermal tumors. This antigen cannot be demonstrated in human epidermis and in epidermal tumors of human patients. (b) The second is histological staining with the DNA-specific fluorochrome, bisbenzimide, displaying a characteristic pattern of 5-10 intranuclear fluorescent bodies in murine nonneoplastic epidermal cells and in murine epidermal tumor cells. Such a pattern is not seen in human epidermis and in epidermal tumors of human patients. The studies showed that TPA treatment resulted in epidermal hyperplasia in both the human epidermis and the adjacent mouse epidermis and that the induced tumors were derived from murine tissue.

  1. A Comparative Account of the Kinetics of Light-Induced E-Z Isomerization of an Anthracene-Based Organogelator in Sol, Gel, Xerogel, and Powder States: Fiber to Crystal Transformation.

    PubMed

    Mondal, Sanjoy; Chakraborty, Priyadarshi; Das, Sujoy; Bairi, Partha; Nandi, Arun K

    2016-05-31

    The organogel of (E)-N'-(anthracene-10-ylmethylene)-3,4,5-tris(dodecyloxy)benzohydrazide (I) in methyl cyclohexane having a fibrillar network structure exhibits excellent fluorescence, which decreases sharply with time upon photoirradiation at λ = 365 nm. It has been attributed to the transformation of the E isomer of I to the Z isomer, and the kinetics of E-Z isomerization are compared for the sol, gel, xerogel, and powder states. The rate constants at different temperatures are measured from Avrami plots and its increase with an increase in temperature, indicating temperature acts as a promoter for photoirradiated E-Z isomeization along the imine (C═N) bond. In the powder form, the rate constant values are the lowest compared to those of other states for all temperatures and the xerogels exhibit the highest rate of E-Z isomerization. The rate constants of sol and gel states mostly lie between the two. The wide-angle X-ray scattering pattern changes after ultraviolet (UV) irradiation with the generation of new sharp peaks whose intensities increase with an increase in irradiation time. A polarized optical microscopic study indicates formation of small crystalline dots on the fibers in the gels, dendritic morphology on the xerogel fibers, and large needlelike morphology at the surface boundary of the solid. The dried I gel exhibits a melting peak at 96.7 °C, but upon irradiation, two peaks are observed at 98.5 and 152.7 °C; the latter has been attributed to the melting of crystals of Z isomers. Similar higher melting peaks are observed both for the xerogel and for powders after UV irradiation; the powders exhibit the highest meting peak at 159.4 °C. Possible reasons for the variation of rate constant values in the four different states and the difference in morphology and melting points of crystals of Z isomers of I are discussed. PMID:27159227

  2. Long-term dysregulation of circadian and 17-beta estradiol-induced LH, prolactin and corticosterone secretion after dimethylbenz (a) anthracene administration in the Sprague-Dawley female rat.

    PubMed

    Yon de Jonage-Canonico, M Beau; Lenoir, V; Scholler, R; Kerdelhué, B

    2005-07-01

    A single intragastric administration of 7,12-dimethylbenz (a) anthracene (DMBA) has been shown, when given at 55-60 days of age, to induce mammary tumors in young cycling female Sprague-Dawley rats. The appearance of the tumors is preceded by a series of neuroendocrine disturbances of the hypothalamo-pituitary-gonadal (HPG) axis, including attenuation of the preovulatory Luteinizing Hormone (LH) and Gonadotropin-Releasing Hormone (GnRH) release and amplification of the preovulatory 17beta-Estradiol (E(2)) surge. In this study, we examined the hypothesis that a single administration of DMBA could also, in the long range, induce disturbances of others neuroendocrine axis, like the Hypothalamic-Pituitary-Adrenal (HPA) axis and/or the Lactotroph axis. Sprague-Dawley rats, 55-60 days of age, received, on the day of Estrous of the Estrous cycle, a single administration of 15 mg of DMBA delivered by intragastric intubation. Then, they were ovariectomized 5 days later. One month later, (1) Two groups of animal were sacrificed by decapitation at 09:00 a.m. and 05:00 p.m. to record the circadian rhythm of plasma LH, Prolactin (PRL) and corticosterone, (2) Three other groups of animal were sacrificed by decapitation at three different times after a morning subcutaneous administration of 50 microg/kg of Estradiol Benzoate (EB), to induce a negative and positive feed-back of the secretion of LH. Then, plasma LH, PRL and corticosterone concentrations were measured. After DMBA administration, (1) the negative--but not the positive--LH feed-back was seen, (2) the PRL circadian rhythm was blunted and the corticosterone circadian rhythm was almost absent, (3) the increase in PRL or Corticosterone plasma concentration was significantly reduced. In conclusion, a single administration of DMBA provokes a long-term dysregulation of not only the HPG axis but also of the lactotroph and HPA axis. These dysregulations, along with the already evidenced long-term inhibition of DMBA upon

  3. Effect of the promoter 12-O-tetradecanolyphorbol-13- acetate on the evolution of carcinogen-altered cell populations in tracheas initiated with 7,12-dimethylbenz(a)anthracene

    SciTech Connect

    Terzaghi, M.; Klein-Szanto, A.; Nettesheim, P.

    1983-04-01

    The aim of these studies was to investigate the effect(s) of the promoter 12-O-tetradecanoylphorbol-13- acetate (TPA) on the evolution of different types of 7,12-dimethylbenz(a)anthracene (DMBA)-initiated rat tracheal epithelial cells in vivo. In the present study, tracheal transplants were exposed in vivo to 35 ..mu..g DMBA for 2 weeks and subsequently to 100 ..mu..g TPA. Controls were exposed to DMBA alone, TPA alone, or blank pellets alone. Tracheal cells were harvested by enzymatic procedures at 0, 3, 6, 12, or 18 months after the end of exposure to DMBA and at the same time points after the beginning of exposure to TPA or control pellets and were assayed in vitro with the epithelial focus (EF) assay for the frequency of different types of EF-forming units. Control tracheas yielded <1 EF/10/sub 4/ viable cells harvested. Exposure to TPA alone did not increase the yield of EF, EF/sub s/, or EF/sub s,ag+/ above control levels. Carcinogen exposure resulted in a 6- to 20-fold increase in yield of EF, a 2- to 3-fold increase in EF/sub s/, and a greater than or equal to 15-fold increase in yield of EF/sub s,ag+/ above control levels. Neither the yield of EF nor the yield of EF/sub s/ was affected by subsequent TPA. In contrast, there was a marked effect of subsequent TPA exposure on the maintenance and size of the cell pool giving rise to anchorage-independent offspring (EF/sub s,ag+/). In summary, it appears that initiation can be viewed as a series of complex cellular changes. With time, some of these changes are reversible. Exposure to TPA of cell populations initiated with low doses of DMBA results in the persistence of altered cell populations in the intact tissue. Without TPA treatment, some phenotypically altered cells appear to revert to a more normal state and/or fail to replicate. 26 references, 1 figure, 1 table.

  4. Influence of caffeine consumption on 7,12-dimethylbenz(a)anthracene-induced mammary gland tumorigenesis in female rats fed a chemically defined diet containing standard and high levels of unsaturated fat.

    PubMed

    Welsch, C W; DeHoog, J V

    1988-04-15

    The effect of caffeine (430-500 mg/liter of drinking water) on the initiation and promotion phases of 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary gland tumorigenesis in female Sprague-Dawley rats fed a chemically defined diet containing standard (5%) or high (20%) levels of fat (corn oil) was examined. In the initiation studies, caffeine and the standard or high fat diet treatments were provided for 34 days, from 24-29 days of age to 58-63 days of age. Three days prior to termination of caffeine-fat diet treatments, each rat received a single dose of DMBA. In the promotion studies, caffeine and the standard or high fat diets were provided commencing 3 days after a single dose of DMBA (at 56-61 days of age) and until termination of the study. Caffeine consumption, during the initiation phase significantly (P less than 0.05) reduced mammary carcinoma multiplicity (number of tumors/rat), in rats fed either a standard or high fat diet. In the promotion studies, prolonged consumption of caffeine in rats fed either a standard or high fat diet did not significantly effect mammary carcinoma multiplicity. In the early stages of promotion, an apparent increase in mammary carcinoma multiplicity was observed; this increase in mammary carcinoma multiplicity did not, however, reach the 5% level of statistical probability. When caffeine was administered during both the initiation and promotion phases, no significant effect on mammary carcinoma multiplicity was observed. Treatment of rats during the initiation or promotion phases with caffeinated coffee (via drinking water) mimicked the mammary tumor modulating activities of caffeine. Decaffeinated coffee consumption did not effect either the initiation or promotion phases of this tumorigenic process. In both the initiation and promotion studies, caffeine and/or coffee consumption did not significantly affect the incidence of mammary carcinomas (percentage of rats bearing mammary carcinomas) or the mean latency period of

  5. Metformin inhibits 7,12-dimethylbenz[a]anthracene-induced breast carcinogenesis and adduct formation in human breast cells by inhibiting the cytochrome P4501A1/aryl hydrocarbon receptor signaling pathway

    SciTech Connect

    Maayah, Zaid H.; Ghebeh, Hazem; Alhaider, Abdulqader A.; El-Kadi, Ayman O.S.; Soshilov, Anatoly A.; Denison, Michael S.; Ansari, Mushtaq Ahmad; Korashy, Hesham M.

    2015-04-15

    Recent studies have established that metformin (MET), an oral anti-diabetic drug, possesses antioxidant activity and is effective against different types of cancer in several carcinogen-induced animal models and cell lines. However, whether MET can protect against breast cancer has not been reported before. Therefore, the overall objectives of the present study are to elucidate the potential chemopreventive effect of MET in non-cancerous human breast MCF10A cells and explore the underlying mechanism involved, specifically the role of cytochrome P4501A1 (CYP1A1)/aryl hydrocarbon receptor (AhR) pathway. Transformation of the MCF10A cells into initiated breast cancer cells with DNA adduct formation was conducted using 7,12-dimethylbenz[a]anthracene (DMBA), an AhR ligand. The chemopreventive effect of MET against DMBA-induced breast carcinogenesis was evidenced by the capability of MET to restore the induction of the mRNA levels of basic excision repair genes, 8-oxoguanine DNA glycosylase (OGG1) and apurinic/apyrimidinic endonuclease1 (APE1), and the level of 8-hydroxy-2-deoxyguanosine (8-OHdG). Interestingly, the inhibition of DMBA-induced DNA adduct formation was associated with proportional decrease in CYP1A1 and in NAD(P)H:quinone oxidoreductase 1 (NQO1) gene expression. Mechanistically, the involvements of AhR and nuclear factor erythroid 2-related factor-2 (Nrf2) in the MET-mediated inhibition of DMBA-induced CYP1A1 and NQO1 gene expression were evidenced by the ability of MET to inhibit DMBA-induced xenobiotic responsive element and antioxidant responsive element luciferase reporter gene expression which suggests an AhR- and Nrf2-dependent transcriptional control. However, the inability of MET to bind to AhR suggests that MET is not an AhR ligand. In conclusion, the present work shows a strong evidence that MET inhibits the DMBA-mediated carcinogenicity and adduct formation by inhibiting the expression of CYP1A1 through an AhR ligand-independent mechanism

  6. Method validation and simultaneous determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum treated with 7,12 dimethylbenz[a]anthracene and Plantago major L. by high- performance liquid chromatography using diode-array detection.

    PubMed

    Levent, Abdulkadi; Oto, Gokhan; Ekin, Suat; Berber, Ismet

    2013-02-01

    A new and simple high-performance liquid chromatography method was developed and validated for the simultaneous determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum treated with Plantago Major L. and 7,12 dimethylbenz[a]anthracene. High-performance liquid chromatography analysis was performed utilizing an Inertsil ODS3 reversed phase column with methanol-tetrahydrofuran-water as mobile phase under gradient conditions, at 1.5 mL min(-1) flow rate and 25 °C. Diode-array detection was at 325, 450, 290 and 270 nm (retinol and retinyl palmitate), β-carotene, α-tocopherol and vitamin C, respectively and runnig time 18 min. The high-performance liquid chromatography assay and extraction procedure proposed are simple, rapid, sensitive and accurate. The method was then applied for the determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum. Results of this study demonstrated that; at 60th day DMBA-treated group, there was a significant decrease in vitamin levels compared to the levels of control group. A significant increase was observed in vitamin levels of 7,12 dimethylbenz[α]anthracene+Plantago Major L.-treated group compared to the DMBA-treated group. Additionally, the results obtained in the study are found to be in agreement with data reported in the literature. PMID:23176060

  7. Method validation and simultaneous determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum treated with 7,12 dimethylbenz[a]anthracene and Plantago major L. by high- performance liquid chromatography using diode-array detection.

    PubMed

    Levent, Abdulkadi; Oto, Gokhan; Ekin, Suat; Berber, Ismet

    2013-02-01

    A new and simple high-performance liquid chromatography method was developed and validated for the simultaneous determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum treated with Plantago Major L. and 7,12 dimethylbenz[a]anthracene. High-performance liquid chromatography analysis was performed utilizing an Inertsil ODS3 reversed phase column with methanol-tetrahydrofuran-water as mobile phase under gradient conditions, at 1.5 mL min(-1) flow rate and 25 °C. Diode-array detection was at 325, 450, 290 and 270 nm (retinol and retinyl palmitate), β-carotene, α-tocopherol and vitamin C, respectively and runnig time 18 min. The high-performance liquid chromatography assay and extraction procedure proposed are simple, rapid, sensitive and accurate. The method was then applied for the determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum. Results of this study demonstrated that; at 60th day DMBA-treated group, there was a significant decrease in vitamin levels compared to the levels of control group. A significant increase was observed in vitamin levels of 7,12 dimethylbenz[α]anthracene+Plantago Major L.-treated group compared to the DMBA-treated group. Additionally, the results obtained in the study are found to be in agreement with data reported in the literature.

  8. (+)-2-(1,2,3,4,4a,5,6,7-Octahydro-4a,8-dimethyl-7-oxo-2-naphthyl)propionic acid: catemeric hydrogen bonding in a bicyclic sesquiterpenoid keto acid.

    PubMed

    Brunskill, Andrew P J; Thompson, Hugh W; Lalancette, Roger A

    2002-05-01

    The title compound, C(15)H(22)O(3), derived from a naturally occurring sesquiterpenoid, has two molecules in the asymmetric unit, differing principally in the rotational conformation of the carboxyl group. Each species aggregates separately as a carboxyl-to-ketone hydrogen-bonding catemer [O.O = 2.752 (4) and 2.682 (4) A, and O-H.O = 161 (4) and 168 (4) degrees ], producing two crystallographically independent single-strand hydrogen-bonding helices, with opposite end-to-end orientations, passing through the cell in the b direction. Three intermolecular C-H.O=C close contacts exist for the ketone. PMID:11983981

  9. Synthesis and Property of New Propeller Shaped Emitting Materials for Organic Light-Emitting Devices.

    PubMed

    Kang, Seokwoo; Lee, Hayoon; Kim, Beomjin; Park, Youngil; Park, Jongwook

    2016-03-01

    New propeller type emitting compound, namely 3,6-di-anthracen-9-yl-9,10-bis-(4-anthracen-9-yi-phenyl)-phenanthrene[TAnDAP] and 3,6-bis-(10-phenyl-anthracen-9-yl)-9,10-bis-[4-(10-phenyl-anthracen-9-yl)-phenyl]-phenanthrene [TAnPDAP] were synthesized through Suzuki and McMurry reactions. We investigated their physical properties such as optical, electrochemical, and electroluminescent properties. The two compounds were used as an emitting layer in OLED devices: ITO/2-TNATA (60 nm)/NPB (15 nm)/non-doped: TAnDAP or TAnPDAP (35 nm)/Alq3 (20 nm)/LiF (1 nm)/Al (200 nm). The TAnDAP OLED device showed C.I.E. value of (0.28, 0.41) and luminance efficiency of 3.81 cd/A at 10 mA/cm2. The TAnPDAP device showed C.I.E. value of (0.20, 0.27) and high luminance efficiency of 5.40 cd/A at 10 mA/cm2. TAnPDAP was found to show better luminance efficiency and C.I.E. value than TAnDAP because it has a bulky 9-phenylanthracene.

  10. Synthesis and reactivity of ((eta/sup 5/-C/sub 5/R/sub 5/)Ru(eta/sup 6/-arene))PF/sub 6/ (R = H, CH/sub 3/) complexes of naphthalene, anthracene, pyrene, chrysene, and azulene. Kinetic studies of arene displacement reactions in acetonitrile solutions

    SciTech Connect

    McNair, A.M.; Mann, K.R.

    1986-07-16

    The synthesis and characterization of new ((eta/sup 5/-C/sub 5/H/sub 5/)Ru(eta/sup 6/-arene))PF/sub 6/ and ((eta/sup 5/-C/sub 5/(CH/sub 3/)/sub 5/)Ru(eta/sup 6/-arene))PF/sub 6/ complexes are reported (arene = naphthalene, anthracene, pyrene, chrysene, azulene). Kinetic studies of arene displacement by acetonitrile for five of these complexes are reported. The values obtained for k/sub obsd/ range from 1.3 x 10/sup -2/ s/sup -1/ to 4.6 x 10/sup -6/ s/sup -1/ in 2.73 M CH/sub 3/CN. The differences between the rates observed for the C/sub 5/H/sub 5//sup -/ complexes and the C/sub 5/(CH/sub 3/)/sub 5//sup -/ compound are explained in terms of an associative mechanism. Rate constants for the ruthenium compounds containing pyrene and chrysene were found to be approximately 4 orders of magnitude larger, respectively, than those for the corresponding Fe complexes. This is believed to be an effect of the difference in the sizes of the two metals and their subsequent susceptibility toward nucleophilic attack. The temperature and concentration dependence of the rate constant k was studied for the reaction of (eta/sup 5/-C/sub 5/(CH/sub 3/)/sub 5/)Ru(eta/sub 6/-anthracene))/sup +/ with CH/sub 3/CN. The ..delta..S double dagger of -13.3 (9) eu and ..delta..H double dagger = +14.9 (3) kcal/mol confirm the associative nature of the displacement reaction. The straight-line plot obtained for k/sub obsd/ vs. (CH/sub 3/CN) is consistent with a rate equation of the general form rate = k(M)(CH/sub 3/CH) where (M) is the concentration of the metal complex. Two mechanisms consistent with the data are proposed and discussed; on includes a preequilibrium between a eta/sup 6/-arene metal complex and a eta/sup 4/-arene species, while the other involves direct nucleophilic attack on the metal-center of the eta/sup 6/ complex.

  11. Characteristics of blue organic light emitting diodes with different thick emitting layers

    NASA Astrophysics Data System (ADS)

    Li, Chong; Tsuboi, Taiju; Huang, Wei

    2014-08-01

    We fabricated blue organic light emitting diodes (called blue OLEDs) with emitting layer (EML) of diphenylanthracene derivative 9,10-di(2-naphthyl)anthracene (ADN) doped with blue-emitting DSA-ph (1-4-di-[4-(N,N-di-phenyl)amino]styryl-benzene) to investigate how the thickness of EML and hole injection layer (HIL) influences the electroluminescence characteristics. The driving voltage was observed to increase with increasing EML thickness from 15 nm to 70 nm. The maximum external quantum efficiency of 6.2% and the maximum current efficiency of 14 cd/A were obtained from the OLED with 35 nm thick EML and 75 nm thick HIL. High luminance of 120,000 cd/m2 was obtained at 7.5 V from OLED with 15 nm thick EML.

  12. Memory bistable mechanisms of organic memory devices

    NASA Astrophysics Data System (ADS)

    Lee, Ching-Ting; Yu, Li-Zhen; Chen, Hung-Chun

    2010-07-01

    To investigate the memory bistable mechanisms of organic memory devices, the structure of [top Au anode/9,10-di(2-naphthyl)anthracene (ADN) active layer/bottom Au cathode] was deposited using a thermal deposition system. The Au atoms migrated into the ADN active layer was observed from the secondary ion mass spectrometry. The density of 9.6×1016 cm-3 and energy level of 0.553 eV of the induced trapping centers caused by the migrated Au atoms in the ADN active layer were calculated. The induced trapping centers did not influence the carrier injection barrier height between Au and ADN active layer. Therefore, the memory bistable behaviors of the organic memory devices were attributed to the induced trapping centers. The energy diagram was established to verify the mechanisms.

  13. Optical and morphological characteristics of organic thin films for optoelectronic devices

    NASA Astrophysics Data System (ADS)

    Zhong, Zhiyou; Sun, Fenglou

    2007-12-01

    Organic semiconductor thin films of tri-(8-hydroxyquinoline)-aluminum (Alq), 9,10-di-(2-naphthyl)-anthracene (ADN), and N,N'bis(naphthalen-1-yl)-N,N'bis(phenyl)-benzidine (NPB) for optoelectronic devices were deposited onto glass substrates by vacuum sublimation technique. The surface morphology and roughness of the thin film were characterized by means of atomic force microscopy (AFM). Experimental results indicate that all thin films present similar granular topography but different surface roughness. In addition, the optical transmittance spectra of thin films were measured by a double beam spectrophotometer and their corresponding optical properties were investigated. The complex refractive index and the optical band gap of thin films were obtained, respectively. Meanwhile, the dispersion behavior of the refractive index was studied in terms of Wemple-DiDomenico single oscillator model, and the oscillator parameters were achieved.

  14. White organic light-emitting diodes based on incomplete energy transfer from perylene to rubrene

    NASA Astrophysics Data System (ADS)

    Ding, Bangdong; Zhu, Wenqing; Jiang, Xueyin; Zhang, Zhilin

    2008-11-01

    This paper presents organic light-emitting diodes which generate white emission based on both perylene and rubrene doped in 9,10-di(2-naphthyl)anthracene (ADN). In this doping system, the blue dopant perylene not only emitted but also assisted the energy transfer from ADN to rubrene, which contributes to a lower doping concentration of rubrene. The optimal configuration of the device is ITO/TPD(50 nm)/ADN:0.5 wt% perylene:0.006 wt% rubrene(40 nm)/Bphen(25 nm)/LiF(1 nm)/Al. The maximum luminance of 11 665 cd/m 2 at 14 V according to a luminance efficiency of 2.9 cd/A was obtained. A CIE color coordinate of (0.30, 0.37) at 4 mA/cm 2 was also achieved.

  15. Solution-Processable Low-Molecular Weight Extended Arylacetylenes: Versatile p-Type Semiconductors for Field-Effect Transistors and Bulk Heterojunction Solar Cells

    SciTech Connect

    Silvestri, Fabio; Marrocchi, Assunta; Seri, Mirko; Kim, Choongik; Marks, Tobin J.; Facchetti, Antonio; Taticchi, Aldo

    2010-04-08

    We report the synthesis and characterization of a series of five extended arylacetylenes, 9,10-bis-{[m,p-bis(hexyloxy)phenyl]ethynyl}-anthracene (A-P6t, 1), 9,10-bis-[(p-{[m,p-bis(hexyloxy) phenyl]ethynyl}phenyl)ethynyl]-anthracene (PA-P6t, 2), 4,7-bis-{[m,p-bis(hexyloxy)phenyl]ethynyl}-2,1,3-benzothiadiazole (BTZ-P6t, 5), 4,7-bis(5-{[m,p-bis(hexyloxy)phenyl]ethynyl}thien-2-yl)-2,1,3-benzothiadiazole (TBTZ-P6t, 6), and 7,7'-({[m,p-bis(hexyloxy)phenyl]ethynyl}-2,1,3-benzothiadiazol-4,4'-ethynyl)-2,5-thiophene (BTZT-P6t, 7), and two arylvinylenes, 9,10-bis-{(E)-[m,p-bis(hexyloxy)phenyl]vinyl}-anthracene (A-P6d, 3), 9,10-bis-[(E)-(p-{(E)-[m,p-bis(hexyloxy)phenyl]vinyl}phenyl)vinyl]-anthracene (PA-P6d, 4). Trends in optical absorption spectra and electrochemical redox processes are first described. Next, the thin-film microstructures and morphologies of films deposited from solution under various conditions are investigated, and organic field-effect transistors (OFETs) and bulk heterojunction photovoltaic (OPV) cells fabricated. We find that substituting acetylenic for olefinic linkers on the molecular cores significantly enhances device performance. OFET measurements reveal that all seven of the semiconductors are FET-active and, depending on the backbone architecture, the arylacetylenes exhibit good p-type mobilities (μ up to ~0.1 cm2 V-1 s-1) when optimum film microstructural order is achieved. OPV cells using [6,6]-phenyl C61-butyric acid methyl ester (PCBM) as the electron acceptor exhibit power conversion efficiencies (PCEs) up to 1.3% under a simulated AM 1.5 solar irradiation of 100 mW/cm2. These results demonstrate that arylacetylenes are promising hole-transport materials for p-channel OFETs and promising donors for organic solar cells applications. A direct correlation between OFET arylacetylene hole mobility and OPV performance is identified and analyzed.

  16. [C70] fullerene-sensitized triplet-triplet annihilation upconversion.

    PubMed

    Moor, Kyle; Kim, Jae-Hyuk; Snow, Samuel; Kim, Jae-Hong

    2013-11-28

    We herein report the first instance of using pristine C70 as a heavy-atom free organic sensitizer for efficient triplet-triplet annihilation upconversion (UC) for both green-to-blue and red-to-green UC using 9,10-bis(phenylethynyl)anthracene and perylene as acceptors, respectively. C70 achieved quantum yields of 8% and 0.8% for green-to-blue and red-to-green UC, 25 to 35 times higher than C60, and showed improved stability under continuous laser irradiation compared to the benchmark platinum(II)-octaethylporphyrin.

  17. Single-displacement controlled spontaneous electrolysis towards CuTCNQ microribbon electrodes in organic single-crystal transistors.

    PubMed

    He, Liangfu; Ji, Zhuoyu; Zhen, Yonggang; Liu, Jie; Yang, Fangxu; Zhao, Qiang; Dong, Huanli; Hu, Wenping

    2015-10-28

    Using single-displacement controlled spontaneous electrolysis solution-prepared CuTCNQ microribbons as the source/drain electrodes, we have fabricated 9,10-bis(2-phenylethynyl)anthracene (BEPA) based organic single crystal top-contact field-effect transistors. The interfacial energetic match between organic semiconductors and CuTCNQ electrodes with the low contact resistance accounts for the compelling improvement in electrical characteristics relative to the copper electrode, even comparable to gold counterparts. Furthermore, we have estimated the contact resistance of single-crystal transistors by the transfer line method (TLM).

  18. The Comparative Nucleophilicity of Naphthoxide Derivatives in Reactions with a Fast-Red TR Dye: A Discovery-Oriented Capstone Project for the Second-Year Organic Laboratory

    ERIC Educational Resources Information Center

    Mascarenhas, Cheryl M.

    2008-01-01

    In this experiment, organic chemistry students perform reactions between three naphthyl acetate derivatives and the diazonium salt Fast-Red TR, under basic conditions. The three naphthyl acetate derivatives used in this study are 2-naphthyl acetate (1a), 6-bromo-2-naphthyl acetate (1b) and 1,6-dibromo-2-naphthyl acetate (1c). The two-step, one-pot…

  19. Localized surface plasmon effects of two dimensional lattice of metal nanoislands

    NASA Astrophysics Data System (ADS)

    Oda, Yukari; Shimada, Ryoko; Japan Women's University Team

    2015-03-01

    Localized surface plasmon (LSP) of metal nanoparticles results from non-propagating excitation of their conduction electrons coupled to the electromagnetic field. LSP localizes the electric field and enhances light emission from fluorescent materials. In this study, a two dimensional (2D) lattice of silver (Ag) nanoislands was fabricated by nanosphere lithography (NSL) method utilizing self-assembled, close-packed hexagonal structures of polystyrene spheres as the etching mask. This 2D lattice was subjected to the electric field for investigating a role of the periodicity of metal islands in the LSP effect. 9,10-di(2-naphthyl) anthracene (ADN), a well-known blue-emitting material in the field of electroluminescence, was used for the study of the enhancement of emission due to the LSP effect. Hybrid thin films of poly(methyl methacrylate) containing ADN were prepared with spin-casting onto the 2D lattice of Ag nanoislands. Transmission and photoluminescence measurements were conducted for these hybrid thin films at room temperature. Detailed results will be presented on site.

  20. The effect of a charge control layer on the electroluminescent characteristic of blue and white organic light-emitting diodes.

    PubMed

    Lee, Dong Hyung; Lee, Seok Jae; Koo, Ja-Ryong; Lee, Ho Won; Shin, Hyun Su; Lee, Song Eun; Kim, Woo Young; Lee, Kum Hee; Yoon, Seung Soo; Kim, Young Kwan

    2014-08-01

    We investigated blue fluorescent organic light-emitting diode (OLED) with a charge control layer (CCL) to produce high efficiency and improve the half-decay lifetime. Three types of devices (device A, B, and C) were fabricated following the number of CCLs within the emitting layer (EML), maintaining the thickness of whole EML. The CCL and host material, 2-methyl-9,10-di(2-naphthyl)anthracene, which has a bipolar property, was able to control the carrier movement with ease inside the EML. Device B demonstrated a maximum luminous efficiency (LE) and external quantum efficiency (EQE) of 9.19 cd/A and 5.78%, respectively. It also showed that the enhancement of the half-decay lifetime, measured at an initial luminance of 1,000 cd/m2, was 1.5 times longer than that of the conventional structure. A hybrid white OLED (WOLED) was also fabricated using a phosphorescent red emitter, bis(2-phenylquinoline)-acetylacetonate iridium III doped in 4,4'-N,N'-dicarbazolyl-biphenyl. The property of the hybrid WOLED with CCL showed a maximum LE and an EQE of 13.46 cd/A and 8.32%, respectively. It also showed white emission with Commission International de L'Éclairage coordinates of (x = 0.41, y = 0.33) at 10 V. PMID:25936005

  1. Investigation of Förster-type energy transfer in organic light-emitting devices with 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethy ljulolidin-4-yl-vinyl)-4H-pyran doped cohost emitting layer

    NASA Astrophysics Data System (ADS)

    Yu, Li-Zhen; Jiang, Xue-Yin; Zhang, Zhi-Lin; Lou, Li-Ren; Lee, Ching-Ting

    2009-01-01

    Organic light-emitting devices (OLEDs) with cohosted emitter, which is composed of 9,10-di(2-naphthyl)anthracene (ADN) and tris(8-hydroxy-quinolinato) aluminum (Alq3) and doped with 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethy ljulolidin-4-yl-vinyl)-4H-pyran (DCJTB), were fabricated and studied. The efficiency of OLEDs with a cohost emitter was higher than that with a single host emitter. For the cohost emitter with ADN/Alq3 weight ratio of 75:25, the 3.4 cd/A efficiency of the resulted OLEDs was obtained. It is found that the absorption spectra of DCJTB and the emission spectra of Alq3 changed with the composition of the emitter. This phenomenon is attributed to the polarization effect. On the basis of the Förster's theory, the resulted overlap integral exhibits the highest value for this cohost emitter. The experimental results reveal that the cascade energy transfer plays an important role in the luminance efficiency enhancement of the cohost emitter in OLEDs.

  2. Improvement of efficiency and stability utilizing a wide band gap material as the host for red organic light-emitting diodes

    NASA Astrophysics Data System (ADS)

    Tang, Hao; Li, Ying; Wang, Xiuru; Wang, Wengen; Sun, Runguang

    2007-03-01

    We present red organic light-emitting diodes (OLEDs) with high efficiency and stability based on a wide band gap host material 9,10-di (2-naphthyl) anthracene (ADN). In these diodes, N,N'-bis(1-naphthyl)-N,N'-diphenyl-1, 1'-biphenyl-4,4'diamine(NPB) and tris-(8- ydroxy-quinoline) aluminium (Alq) are used as hole and electron transport layers, respectively. 2,3,6,7-tetrahydro-1,1,7,7,-tetramethyl- 1H,5H,11H-10-(2-benzothiazolyl) quinolizino-[9,9a,1gh] coumarin (C545T) and 4-(dicyano-methylene)-2- t-butyl-6-(1,1,7,7-tetramethyl-julolidyl-9-enyl)-4H-pyran (DCJTB) are co-doped into the ADN emitting layer. Utilizing the two-step energy transfer from ADN to C545T and then from C545T to DCJTB, we achieved pure red organic light-emitting devices, which showed improved optical and electrical characteristics. Compared with devices where the emitting layer is made of Alq and DCJTB, the emission efficiency and stability of the ADN-based devices are greatly improved and the turn-on voltage is also decreased. The co-doping technique provides a promising way of utilizing wide band gap materials as the host to make red OLEDs, which will be useful in improving the electroluminesent performance of devices and simplifying the process of fabricating full colour OLEDs.

  3. Highly fluorescent N,N-dimethylaminophenylethynylarenes: synthesis, photophysical properties, and electrochemiluminescence.

    PubMed

    Ho, Tong-Ing; Elangovan, Arumugasamy; Hsu, Hsien-Yi; Yang, Shu-Wen

    2005-05-12

    A new family of aryl-pi-donor-aryl molecules has been synthesized and studied with respect to their photophysical properties and electrogenerated chemiluminscence (ECL) for the first time. Anthracene, phenanthrene, naphthalene, biphenyl, and fluorene were coupled with N,N-dimethylanilino moiety via a C-C triple bond (1-7). Introduction of such a strong electron-donating moiety as N,N-dimethylanilino group through a triple bond imparts new properties to the resultant molecules that are not commonly observed for the parent arenes. All molecules show absorption in the near-visible region and emission totally in the visible region with high fluorescence quantum yields. Bright solid-state photoluminescence has also been noticed for all the compounds in the visible region. 9-Anthryl- and 1-naphthyl- derivatives exhibited blue-shifted electrochemiluminescence (ECL) relative to their photoluminescence because of aggregation. 9-Phenanthryl- and 2-naphthyl- derivatives did not show ECL. 2-Biphenyl derivative showed monomeric ECL while 4-biphenyl counterpart exhibited excimer ECL. No ECL was observed for 2-fluorenyl derivative. The observed electronic properties are discussed with regard to the structure of the molecules. The characteristics of the molecules chosen in the present study open up new prospects and promises for novel tunable organic materials, on the basis of simple extension of conjugation to promote intramolecular communication, for ECL, OLED, and other optoelectronic applications.

  4. High-mobility bio-organic field effect transistors with photoreactive DNAs as gate insulators

    NASA Astrophysics Data System (ADS)

    Kim, Youn Sun; Jung, Ki Hwa; Lee, U. Ra; Kim, Kyung Hwan; Hoang, Mai Ha; Jin, Jung-Il; Choi, Dong Hoon

    2010-03-01

    Organic-soluble DNAs bearing chalcone moieties were synthesized by using purified natural sodium DNA. In addition to the chalcone-containing DNA homopolymer (CcDNA), a copolymer (CTMADNA-co-CcDNA) was synthesized. They were employed as gate insulators for fabricating organic thin-film transistors. An organic semiconductor (5,5'-(9,10-bis((4-hexylphenyl)ethynyl)anthracene-2,6-yl-diyl)bis(ethyne-2,1-diyl)bis(2-hexylthiophene; HB-ant-THT) was deposited on the photocrosslinked DNA-based gate insulators via a solution process. Interestingly, the resulting TFT devices had extremely high field-effect mobilities, and their corresponding transfer curves indicated low hysteresis. The carrier mobility of the device with HB-ant-THT deposited on the CTMADNA-co-CcDNA gate insulator was the best, i.e., 0.31 cm2 V-1 s-1 (Ion/Ioff=1.0×104).

  5. Screening of pi-basic naphthalene and anthracene amplifiers for pi-acidic synthetic pore sensors.

    PubMed

    Hagihara, Shinya; Gremaud, Ludovic; Bollot, Guillaume; Mareda, Jiri; Matile, Stefan

    2008-04-01

    Synthetic ion channels and pores attract current attention as multicomponent sensors in complex matrixes. This application requires the availability of reactive signal amplifiers that covalently capture analytes and drag them into the pore. pi-Basic 1,5-dialkoxynaphthalenes (1,5-DAN) are attractive amplifiers because aromatic electron donor-acceptor (AEDA) interactions account for their recognition within pi-acidic naphthalenediimide (NDI) rich synthetic pores. Focusing on amplifier design, we report here the synthesis of a complete collection of DAN and dialkoxyanthracene amplifiers, determine their oxidation potentials by cyclic voltammetry, and calculate their quadrupole moments. Blockage experiments reveal that subtle structural changes in regioisomeric DAN amplifiers can be registered within NDI pores. Frontier orbital overlap in AEDA complexes, oxidation potentials, and, to a lesser extent, quadrupole moments are shown to contribute to isomer recognition by synthetic pores. Particularly important with regard to practical applications of synthetic pores as multianalyte sensors, we further demonstrate that application of the lessons learned with DAN regioisomers to the expansion to dialkoxyanthracenes provides access to privileged amplifiers with submicromolar activity.

  6. Preparation, characterization, physical properties, and photoconducting behaviour of anthracene derivative nanowires

    NASA Astrophysics Data System (ADS)

    Xiao, Jinchong; Yin, Zongyou; Yang, Bo; Liu, Yi; Ji, Li; Guo, Jun; Huang, Ling; Liu, Xuewei; Yan, Qingyu; Zhang, Hua; Zhang, Qichun

    2011-11-01

    Organic nanowires of 9,10-dibromoanthracene (DBA) and 9,10-dicyanoanthracene (DCNA) were obtained by adding the THF solution of DBA/DCNA into water containing P123 surfactants. The as-prepared nanowires were characterized by UV-vis, fluorescence spectra, Field Emission Scanning Electron Microscopy (FESEM), and Transmission Electron Microscopy (TEM). We found that DBA and DCNA nanowires emitted green light rather than blue light for molecules in THF solution. The red-shift UV and fluorescent spectra of DBA and DCNA nanowires implied that these nanowires were formed through J-aggregation. The photoconducting study of DBA/DCNA nanowire-based network on rGO/SiO2/Si shows different photocurrent behaviors upon irradiation, which displayed that electron transfer from DCNA nanowire to rGO was stronger than that of DBA nanowires to rGO.Organic nanowires of 9,10-dibromoanthracene (DBA) and 9,10-dicyanoanthracene (DCNA) were obtained by adding the THF solution of DBA/DCNA into water containing P123 surfactants. The as-prepared nanowires were characterized by UV-vis, fluorescence spectra, Field Emission Scanning Electron Microscopy (FESEM), and Transmission Electron Microscopy (TEM). We found that DBA and DCNA nanowires emitted green light rather than blue light for molecules in THF solution. The red-shift UV and fluorescent spectra of DBA and DCNA nanowires implied that these nanowires were formed through J-aggregation. The photoconducting study of DBA/DCNA nanowire-based network on rGO/SiO2/Si shows different photocurrent behaviors upon irradiation, which displayed that electron transfer from DCNA nanowire to rGO was stronger than that of DBA nanowires to rGO. Electronic supplementary information (ESI) available: XRD patterns and simulations, and FT-IR spectra. CCDC reference numbers 840471. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c1nr10655d

  7. Anthracene derivative covalently immobilized on sensing membrane as a fluorescent carrier for water assay.

    PubMed

    Jiao, Chen-Xu; Han, Yuan-Yuan; Xing, Bao-Yan

    2013-01-01

    This article describes an optical chemical sensor based on a fluorescent dye 1-allyloxy-4-hydroxyanthracene-9, 10-dione (AHD) with terminal double bond, which is covalently bonded to quartz glass plate surface treated with a silanizing agent to prevent its leakage. The purpose of this work was to characterize and optimize the sensor for determining the water content in the acetone organic solvent. The sensor is resistant to swelling; the membrane possesses relatively long lifetime, short response and recovering time. The reversibility and reproducibility of the sensor are adequate for practical measurements.

  8. Highly conductive single naphthalene and anthracene molecular junction with well-defined conductance

    SciTech Connect

    Liu, Chenyang; Kaneko, Satoshi; Komoto, Yuki; Fujii, Shintaro Kiguchi, Manabu

    2015-03-09

    We performed electronic investigation on single acene molecular junctions bridging Au-electrodes in ultra-high vacuum conditions using mechanically controllable break junction technique. While the molecular junctions displayed various conductance values at 100 K, they exhibited well-defined high conductance values (∼0.3 G{sub 0}) at 300 K, which is close to that of metal atomic contact. Direct π-binding of the molecules to the Au-electrodes leads to the high conductivities at the metal-molecule interface. At the elevated temperature, single molecular junctions trapped in local metastable structures can be fallen into energetically preferential more stable state and thus we fabricated structurally well-defined molecular junctions.

  9. Anthracene-based inhibitors of dengue virus NS2B-NS3 protease.

    PubMed

    Tomlinson, Suzanne M; Watowich, Stanley J

    2011-02-01

    Dengue virus (DENV) is a mosquito-borne flavivirus that has strained global healthcare systems throughout tropical and subtropical regions of the world. In addition to plaguing developing nations, it has re-emerged in several developed countries with recent outbreaks in the USA (CDC, 2010), Australia (Hanna et al., 2009), Taiwan (Kuan et al., 2010) and France (La Ruche et al., 2010). DENV infection can cause significant disease, including dengue fever, dengue hemorrhagic fever, dengue shock syndrome, and death. There are no approved vaccines or antiviral therapies to prevent or treat dengue-related illnesses. However, the viral NS2B-NS3 protease complex provides a strategic target for antiviral drug development since NS3 protease activity is required for virus replication. Recently, we reported two compounds with inhibitory activity against the DENV protease in vitro and antiviral activity against dengue 2 (DEN2V) in cell culture (Tomlinson et al., 2009a). Analogs of one of the lead compounds were purchased, tested in protease inhibition assays, and the data evaluated with detailed kinetic analyses. A structure activity relationship (SAR) identified key atomic determinants (i.e. functional groups) important for inhibitory activity. Four "second series" analogs were selected and tested to validate our SAR and structural models. Here, we report improvements to inhibitory activity ranging between ∼2- and 60-fold, resulting in selective low micromolar dengue protease inhibitors.

  10. Fluorescence of new o-carborane compounds with different fluorophores: can it be tuned?

    PubMed

    Ferrer-Ugalde, Albert; González-Campo, Arántzazu; Viñas, Clara; Rodríguez-Romero, Jesús; Santillan, Rosa; Farfán, Norberto; Sillanpää, Reijo; Sousa-Pedrares, Antonio; Núñez, Rosario; Teixidor, Francesc

    2014-08-01

    Two sets of o-carborane derivatives incorporating fluorene and anthracene fragments as fluorophore groups have been successfully synthesized and characterized, and their photophysical properties studied. The first set, comprising fluorene-containing carboranes 6-9, was prepared by catalyzed hydrosilylation reactions of ethynylfluorene with appropriate carboranylsilanes. The compound 1-[(9,9-dioctyl-fluorene-2-yl)ethynyl]carborane (11) was synthesized by the reaction of 9,9-dioctyl-2-ethynylfluorene and decaborane (B10H14). Furthermore, reactions of the lithium salt of 11 with 1 equivalent of 4-(chloromethyl)styrene or 9-(chloromethyl)anthracene yielded compounds 12 and 13. Members of the second set of derivatives, comprising anthracene-containing carboranes, were synthesized by reactions of monolithium or dilithium salts of 1-Me-1,2-C2B10H11, 1-Ph-1,2-C2B10H11, and 1,2-C2B10H12 with 1 or 2 equivalents of 9-(chloromethyl)anthracene, respectively, to produce compounds 14-16. In addition, 2 equivalents of the monolithium salts of 1-Me-1,2-C2B10H11 (Me-o-carborane) and 1-Ph-1,2-C2B10H11 (Ph-o-carborane) were reacted with 9,10-bis(chloromethyl)anthracene to produce compounds 17 and 18, respectively. Fluorene derivatives 6-9 exhibit moderate fluorescence quantum yields (32-44 %), whereas 11-13, in which the fluorophore is bonded to the Ccluster (Cc), show very low emission intensity (6 %) or complete fluorescence quenching. The anthracenyl derivatives containing the Me-o-carborane moiety exhibit notably high fluorescence emissions, with ϕF = 82 and 94 %, whereas their Ph-o-carborane analogues are not fluorescent at all. For these compounds, we have observed a correlation between the Cc-Cc bond length and the fluorescence intensity in CH2Cl2 solution, comparable to that observed for previously reported styrene-containing carboranes. Thus, our hypothesis is that for systems of this type the fluorescence may be tuned and even predicted by changing the

  11. FAST TRACK COMMUNICATION: Al/WO3/Au as the interconnecting layer for efficient tandem white organic light-emitting diodes

    NASA Astrophysics Data System (ADS)

    Zhang, Hongmei; Dai, Yanfeng; Ma, Dongge

    2008-05-01

    White light emission from tandem organic light-emitting diodes consisting of blue and red light units separated by a transparent interconnecting layer of Al/WO3/Au has been realized. The devices have a structure of indium-tin-oxide (ITO)/molybdenum oxide (MoO3) (8 nm)/N, N'-di(naphthalene-1-yl)-N, N'-diphenyl-benzidine (NPB)(100 nm)/p-bis(p-N,N-diphenyl-aminostyryl)benzene) (DSA-ph):2-methyl-9,10-di(2-naphthyl) anthracene (MADN)(40 nm)/tris(8-hydroxylquinoline) aluminium (Alq3) (10 nm)/LiF(1 nm)/Al(2 nm)/WO3(3 nm)/Au(16 nm)/MoO3(5 nm)/NPB(60 nm)/Alq3: 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB)(30 nm)/Alq3(30 nm)/LiF(1 nm)/Al(150 nm). It can be seen that a stable white light emission, including 461 and 491 nm peaks from DSA-ph and 620 nm peak from DCJTB, with Commission International De L'Eclairage chromaticity coordinates from (0.35, 0.33) at 8 V to (0.37, 0.30) at 12 V was obtained. The current efficiency and brightness of the white devices are basically equal to the sum of the blue unit and red unit devices. The maximum brightness reached 20 700 cd m-2 at a bias of 23 V, and the maximum current efficiency was 9.1 cd A-1 at a current density of 0.41 mA cm-2.

  12. [Multiplayer white organic light-emitting diodes with different order and thickness of emission layers].

    PubMed

    Xu, Wei; Lu, Fu-Han; Cao, Jin; Zhu, Wen-Qing; Jiang, Xue-Yin; Zhang, Zhi-Lin; Xu, Shao-Hong

    2008-02-01

    In multilayer OLED devices, the order and thickness of the emission layers have great effect on their spectrum. Based on the three basic colours of red, blue and green, a series of white organic light-emitting diodes(WOLEDS)with the structure of ITO/CuPc(12 nm)/NPB(50 nm)/EML/LiF(1 nm)/Al(100 nm) and a variety of emission layer's orders and thicknesses were fabricated. The blue emission material: 2-t-butyl-9,10-di-(2-naphthyl)anthracene (TBADN) doped with p-bis(p-N, N-diphenyl-amono-styryl)benzene(DSA-Ph), the green emission material: tris-[8-hydroxyquinoline]aluminum(Alq3) doped with C545, and the red emission material: tris-[8-hydroxyquinoline]aluminum( Alq3) doped with 4-(dicyanomethylene)-2-t-butyl-6-(1, 1, 7, 7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) were used. By adjusting the order and thickness of each emission layer in the RBG structure, we got a white OLED with current efficiency of 5.60 cd x A(-1) and Commission Internationale De L'Eclairage (CIE) coordinates of (0. 34, 0.34) at 200 mA x cm(-2). Its maximum luminance reached 20 700 cd x m(-2) at current density of 400 mA x cm(-2). The results were analyzed on the basis of the theory of excitons' generation and diffusion. According to the theory, an equation was set up which relates EL spectra to the luminance efficiency, the thickness of each layer and the exciton diffusion length. In addition, in RBG structure with different thickness of red layer, the ratio of th e spectral intensity of red to that of blue was calculated. It was found that the experimental results are in agreement with the theoretical values. PMID:18479000

  13. Red organic light-emitting diodes based on wide band gap emitting material as the host utilizing two-step energy transfer

    NASA Astrophysics Data System (ADS)

    Haq, Khizar-ul; Shan-peng, Liu; Khan, M. A.; Jiang, X. Y.; Zhang, Z. L.; Zhu, W. Q.

    2008-03-01

    We demonstrated efficient red organic light-emitting diodes based on a host emitting system of 9,10-di(2-naphthyl)anthracene (ADN) co-doped with 4-(dicyano-methylene)-2-t-butyle-6- (1,1,7,7-tetramethyl-julolidyl-9-enyl)-4H-pyran (DCJTB) as a red dopant and 2,3,6,7- tetrahydro-1,1,7,7-tetramethyl-1H,5H,1 1H-10(2-benzothiazolyl)-quinolizine-[9,9a,1gh] coumarin (C545T) as an assistant dopant. The typical device structure was glass substrate/ITO/4,4',4''-tris(N-3-methylphenyl-N-phenylamino) triphenylamine(m-MTDATA)/N,N'-bis-(naphthalene-1-yl)-N,N'-diphenylbenzidine(NPB)/[ADN: DCJTB: C545T/Alq3/LiF/Al]. It was found that C545T dopant did not emit by itself but did assist the energy transfer from the host (ADN) to the red emitting dopant. The red OLEDs realized by this approach not only enhanced the emission color, but also significantly improved the EL efficiency. The EL efficiency reached 3.5 cd A-1 at a current density of 20 mA cm-2, which is enhanced by three times compared with devices where the emissive layer is composed of the DCJTB doped ADN. The saturated red emission was obtained with CIE coordinates (x = 0.618, y = 0.373) at 621 nm, and the device driving voltage is decreased as much as 38%. We attribute these improvements to the assistant dopant (C545T), which leads to the more efficient energy transfer from ADN to DCJTB. These results indicate that the co-doped system is a promising method for obtaining high-efficiency red OLEDs.

  14. Efficiency and Color Coordinate Improvement Using Codopants in Blue Organic Light-Emitting Diode

    NASA Astrophysics Data System (ADS)

    Wang, Xiu Ru; Chen, Jiang Shan; You, Han; Ma, Dong Ge; Sun, Run Guang

    2005-12-01

    The codoping method is applied to fabricate efficient blue organic light-emitting diodes (OLEDs). With the same structure of indium-tin oxide (ITO)/N,N'-bis(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4,4'diamine (NPB)(80 nm)/light-emitting layer (30 nm)/tris-(8-hydroxy-quinoline)aluminum (Alq3) (20 nm)/LiF (1 nm)/Al (120 nm), a set of three devices was manufactured for comparison. For Devices 1, 2, and 3, the light-emitting layers are 9,10-di(2-naphthyl)anthracene (ADN):4,4'-(1,4-phenylenedi-2,1-ethene diyl)bis[N,N-bis(4-methylphenyl)-benzenamine] (DPAVB) (1 wt %), ADN:2,5,8,11-tetra-(t-butyl)-perylene (TBPE) (1 wt %), and ADN:DPAVB (0.3 wt %):TBPE (0.7 wt %), respectively. It is found that the codoped Device 3 has the highest maximum luminance, Electroluminescence (EL) quantum efficiency and color saturation. Further study on the effect of the codopants was through a relative photoluminescence (PL) quantum efficiency measurement. The result shows that the relative PL efficiencies of Devices 1, 2, and 3 are 15.6, 19.3, and 24%, respectively, as determined using an integrating sphere system excited at 375 nm. The codoping method improves the EL efficiency intrinsically. Codopants of the heterogeneous light-emitting molecules may decrease the possibility of self-quenching from the interaction of the homogenous molecules at the same total doping concentration. Furthermore, the decrease in the interaction of homogenous molecules suppresses the light emission from the aggregations thus narrowing the emission spectrum, and results in saturated blue light emission.

  15. Bromelain nanoparticles protect against 7,12-dimethylbenz[a]anthracene induced skin carcinogenesis in mouse model.

    PubMed

    Bhatnagar, Priyanka; Pant, Aditya B; Shukla, Yogeshwer; Chaudhari, Bhushan; Kumar, Pradeep; Gupta, Kailash C

    2015-04-01

    Conventional cancer chemotherapy leads to severe side effects, which limits its use. Nanoparticles (NPs) based delivery systems offer an effective alternative. Several evidences highlight the importance of Bromelain (BL), a proteolytic enzyme, as an anti-tumor agent which however has been limited due to the requirement of high doses at the tumor site. Therefore, we illustrate the development of BL loaded poly (lactic-co-glycolic acid) NPs that show enhanced anti-tumor effects compared to free BL. The formulated NPs with a mean particle size of 130.4 ± 8.81 nm exhibited sustained release of BL. Subsequent investigation revealed enhanced anti-tumor ability of NPs in 2-stage skin tumorigenesis mice model. Reduction in average number of tumors (∼ 2.3 folds), delay in tumorigenesis (∼ 2 weeks), percent tumorigenesis (∼ 4 folds), and percent mortality rate as well as a reduction in the average tumor volume (∼ 2.5 folds) in mice as compared to free BL were observed. The NPs were found to be superior in exerting chemopreventive effects over chemotherapeutic effects at 10 fold reduced dose than free BL, validated by the enhanced ability of NPs (∼ 1.8 folds) to protect the DNA from induced damage. The effects were also supported by histopathological evaluations. NPs were also capable of modulating the expression of pro-apoptotic (P53, Bax) and anti-apoptotic (Bcl2) proteins. Therefore, our findings demonstrate that developed NPs formulation could be used to improve the efficacy of chemotherapy by exerting chemo-preventive effects against induced carcinogenesis at lower dosages. PMID:25619920

  16. Inclusion of an Anthracene-based Fluorophore within Molecular Containers: A Comparative Study of the Cucurbituril and Cyclodextrin Host Families.

    PubMed

    Ganguly, Aniruddha; Ghosh, Soumen; Guchhait, Nikhil

    2016-05-19

    In this paper, the binding interaction of a promising chloride channel blocker, 9-methyl anthroate (9-MA), with two different classes of molecular containers, β-cyclodextrins (β-CD and methyl-β-CD) and cucurbit[7]uril, having comparable cavity dimensions, has been thoroughly demonstrated via inspection of the modulation of the excited-state properties of the emissive molecule. Spectral data suggest that CB7 encapsulates the probe more efficiently in a 1:2 fashion, whereas the efficacies of β-CDs are relatively less and the corresponding stoichiometry is 1:1. Interestingly, despite being thermodynamically much more favorable than the probe-β-CD complexation equilibria, the fraction of probe-CB7 complex formed is appreciably smaller with respect to that of probe-β-CD complexes. This apparent inconsistency has been addressed via the proposition that since the formation of a 1:2 complex is entropically disadvantageous, it is anticipated that the activation barrier of the corresponding reaction is reasonably high, and thus only a small fraction of the reactants are able to surpass the energy barrier to form the products. This proposition has been thoroughly corroborated by fluorescence lifetime measurements at different temperatures. PMID:27119387

  17. 1,6-Dihydr-oxy-3-hydroxy-methyl-8-methoxy-anthracene-9,10-dione monohydrate.

    PubMed

    Wang, Wen-Liang; Sun, Wei; Gu, Qian-Qun; Zhu, Wei-Ming

    2007-12-21

    The title compound, C(16)H(12)O(6)·H(2)O, isolated from the halotolerant fungus Aspergillus variecolor B-17, is also known as questinol monohydrate. In the crystal structure, O-H⋯O hydrogen bonds link the mol-ecules, forming a three-dimensional network. π-π stacking inter-actions consolidate the supra-molecular structure [the shortest inter-planar distances are 3.456 (3), 3.366 (4) and 3.382 (4) Å].

  18. Increased expression of peripheral benzodiazepine receptor (PBR) in dimethylbenz[a]anthracene-induced mammary tumors in rats.

    PubMed

    Mukhopadhyay, Sutapa; Mukherjee, Shyamali; Das, Salil K

    2006-05-01

    Expression of peripheral benzodiazepine receptors (PBR) has been found in every tissue examined; however, it is most abundant in steroid-producing tissues. Although the primary function of PBR is the regulation of steroidogenesis, its existence in nonsteroidogenic tissues as well as in other cellular compartments including the nucleus suggests that there may be other roles for PBR. Our laboratory reported earlier a significant increase of PBR density in the nucleus of DMBA-induced malignant submandibular glands of rats, suggesting a role of PBR in nuclear events of peripheral tissues. Since then numerous studies have demonstrated the abundance of PBR in tumors. Numerous studies implicate a role for cholesterol in the mechanisms underlying cell proliferation and cancer progression. Based on studies with a battery of human breast cancer cell lines and several human tissue biopsies, Hardwick et al. suggested that PBR expression, nuclear localization, and PBR-mediated cholesterol transport into the nucleus are involved in human breast cancer cell proliferation and aggressive phenotype expression. The purpose of the present study is to confirm this hypothesis by developing an animal breast cancer model and correlating the above events with the breast cancer. Weanling rats were maintained on a diet containing animal protein (casein) for 30 days and then a single dose of DMBA in sesame oil (80 mg/kg) was administered by gavage to the animals. Control animals received the vehicle only. After 122 days of DMBA administration, the animals were sacrificed. All tumors were detected by palpation. B(max) of PBRs was 52.6% and 128.4% higher in the non-aggressive and aggressive cancer tissues, respectively, than that in normal tissues. Cholesterol uptake into isolated nuclei was found to be higher in both non-aggressive and aggressive tumor breast tissue than that in control tissue. There was also corresponding increase in B(max) of PBRs in the nucleus of cancer tissues. Furthermore, the nuclear nucleoside triphosphatase (NTPase) activity was found to be higher in aggressive tumor tissues than that in non-aggressive tumor tissues. In conclusion, these data suggest that PBR ligand binding, and PBR-mediated cholesterol transport into the nucleus may be involved in the development of mammary gland adenocarcinoma, thus participating in the advancement of the disease.

  19. Fatty acid profiles of mammary gland tissue in rats following exposure to 7,12-dimethylbenz(a)anthracene

    SciTech Connect

    Lee, H.; Karmali, R.

    1986-03-01

    Prostaglandins have been implicated in the mechanism of DMBA carcinogenesis and tumor-promoting effects of linoleic acid (C18:2 omega 6). Since elevated levels of arachidonate (C20:4 omega 6) products have been reported in various mammary tumors it is important to evaluate changes in pools of this substrate fatty acid and its precursor, linoleic acid. To address this question, total lipid extracts were subjected to TLC separation to obtain phosphatidyl choline (PC), phosphatidyl ethanolamine (PE), and neutral (N) fractions. Fatty acid profiles for each fraction were analyzed by GLC. Three groups of 50 day old female Sprague-Dawley rats were used: Control, DMBA 10mg and 20mg/rat. Mammary gland tissue specimens were excised at 2 week intervals from the time of challenge through appearance of tumors. Individual fatty acid percentages and specific ratios were examined. At 2 weeks post DMBA, the levels of C18:2 omega 6 were increased in all 3 lipid fractions in both DMBA-challenged compared with Control groups. On the other hand, similar trends in C20:4 omega 6 were apparent only in the PE fraction. Also, ratio of 20:4/18:2 showed a marked increase from the Control (0.09) to DMBA-challenged groups (0.47 and 0.42 respectively) in the PE fraction. These results suggest changes in fatty acid profiles during the early phase of DMBA carcinogenesis. Results of similar studies at subsequent stages will also be discussed in detail.

  20. Bromelain nanoparticles protect against 7,12-dimethylbenz[a]anthracene induced skin carcinogenesis in mouse model.

    PubMed

    Bhatnagar, Priyanka; Pant, Aditya B; Shukla, Yogeshwer; Chaudhari, Bhushan; Kumar, Pradeep; Gupta, Kailash C

    2015-04-01

    Conventional cancer chemotherapy leads to severe side effects, which limits its use. Nanoparticles (NPs) based delivery systems offer an effective alternative. Several evidences highlight the importance of Bromelain (BL), a proteolytic enzyme, as an anti-tumor agent which however has been limited due to the requirement of high doses at the tumor site. Therefore, we illustrate the development of BL loaded poly (lactic-co-glycolic acid) NPs that show enhanced anti-tumor effects compared to free BL. The formulated NPs with a mean particle size of 130.4 ± 8.81 nm exhibited sustained release of BL. Subsequent investigation revealed enhanced anti-tumor ability of NPs in 2-stage skin tumorigenesis mice model. Reduction in average number of tumors (∼ 2.3 folds), delay in tumorigenesis (∼ 2 weeks), percent tumorigenesis (∼ 4 folds), and percent mortality rate as well as a reduction in the average tumor volume (∼ 2.5 folds) in mice as compared to free BL were observed. The NPs were found to be superior in exerting chemopreventive effects over chemotherapeutic effects at 10 fold reduced dose than free BL, validated by the enhanced ability of NPs (∼ 1.8 folds) to protect the DNA from induced damage. The effects were also supported by histopathological evaluations. NPs were also capable of modulating the expression of pro-apoptotic (P53, Bax) and anti-apoptotic (Bcl2) proteins. Therefore, our findings demonstrate that developed NPs formulation could be used to improve the efficacy of chemotherapy by exerting chemo-preventive effects against induced carcinogenesis at lower dosages.

  1. Decreased adrenal medullary tyrosine hydroxylase mRNA in DMBA (7,12-dimethylbenz(a)anthracene)-induced mammary carcinoma

    SciTech Connect

    Bunce, O.R.; Badary, O.A.; Abou El-Ela, S.; Hartle, D.K. )

    1991-03-15

    Adrenal cortical hormones suppress initiation and promotion of DMBA-induced mammary tumorigenesis. The authors found a positive correlation between presence of DMBA-induced adrenal cortical necrosis and mammary tumor incidence. Because they find adrenal medullary as well as cortical lesions in tumor bearing (TB) DMBA-treated rats, they evaluated medullary function by quantitating hybridized cDNA- TH-S{sup 35} with in situ TH-mRNA u sing computer assisted quantitative autoradiographic technique. Virgin female Sprague-Dawley rats were given a 10 mg i.g. dose of DMBA. Three wks later, rats were placed on 20% polyunsaturated (PUFA) fat diets containing omega-6 and omega-3 fatty acids. All were killed 15 wks post-DMBA. TH-mRNA levels in adrenal medullae of TB animals were decreased compared to non-TB rats. Histopathology indicated a high incidence of medullary necrosis in TB rats, whereas, adrenal necrosis did not occur in non-TB animals. Adrenal necrosis correlated positively with tumor burden, but no correlation was found between incidence of adrenal lesions and type of PUFA in the diet. The authors suggest that DMBA adrenal necrosis may reduce TH-mRNA in the medulla, compromise its catecholamine synthetic capability, and thereby contribute to the overall metabolic stress condition of TB rats.

  2. Exploring the Intrinsic Piezofluorochromic Mechanism of TPE-An by STS Technique.

    PubMed

    Jin, Shunyu; Tian, Yan; Liu, Fei; Deng, Shaozhi; Chen, Jun; Xu, Ningsheng

    2015-12-01

    9,10-bis(4-(1,2,2-triphenylvinyl)styryl)anthracene (TPE-An) materials have attracted considerable attention in recent years because they have high luminescence efficiency and excellent piezofluorochromic properties, which have potential applications in organic light-emitting display (OLED) area. Scanning tunneling spectroscopy (STS) technique was used to study the piezofluorochromic mechanism of aggregation-induced emission (AIE) materials for the first time. Photoluminescence (PL) experiments revealed that the emission peak of TPE-An is observed to exhibit a red-shift with the increase of the grinding time. A theoretical calculation was carried out to find the relationship between the bandgap of TPE-An and the external force by combination of the classical tunneling theory and STS results. It is found that when the pressure variation on the surface of TPE-An film was increased to be over 4.38 × 10(4) Pa, the shrink of the highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gap can arrive at 1.1 eV. It is concluded that the piezofluorochromic behaviors of TPE-An should originate from the shrinking effect of the bandgap under external force. Moreover, this research method may shed light on comprehending and adjusting the piezofluorochromic characters of other AIE materials. PMID:26334542

  3. Multiphoton harvesting metal–organic frameworks

    PubMed Central

    Quah, Hong Sheng; Chen, Weiqiang; Schreyer, Martin K.; Yang, Hui; Wong, Ming Wah; Ji, Wei; Vittal, Jagadese J.

    2015-01-01

    Multiphoton upconversion is a process where two or more photons are absorbed simultaneously to excite an electron to an excited state and, subsequently, the relaxation of electron gives rise to the emission of a photon with frequency greater than those of the absorbed photons. Materials possessing such property attracted attention due to applications in biological imaging, photodynamic therapy, three-dimensional optical data storage, frequency-upconverted lasing and optical power limiting. Here we report four-photon upconversion in metal–organic frameworks containing the ligand, trans, trans-9,10-bis(4-pyridylethenyl)anthracene. The ligand has a symmetrical acceptor–π–donor–π–acceptor structure and a singlet biradical electronic ground state, which boosted its multiphoton absorption cross-sections. We demonstrate that the upconversion efficiency can be enhanced by Förster resonance energy transfer within host–guest metal–organic frameworks consisting of encapsulated high quantum yielding guest molecules. Using these strategies, metal–organic framework materials, which can exhibit frequency-upconverted photoluminescence excited by simultaneous multiphoton absorption, can be rationally designed and synthesized. PMID:26245741

  4. Quick Fabrication of Large-area Organic Semiconductor Single Crystal Arrays with a Rapid Annealing Self-Solution-Shearing Method

    PubMed Central

    Li, Yunze; Ji, Deyang; Liu, Jie; Yao, Yifan; Fu, Xiaolong; Zhu, Weigang; Xu, Chunhui; Dong, Huanli; Li, Jingze; Hu, Wenping

    2015-01-01

    In this paper, we developed a new method to produce large-area single crystal arrays by using the organic semiconductor 9, 10-bis (phenylethynyl) anthracene (BPEA). This method involves an easy operation, is efficient, meets the demands of being low-cost and is independent of the substrate for large-area arrays fabrication. Based on these single crystal arrays, the organic field effect transistors exhibit the superior performance with the average mobility extracting from the saturation region of 0.2 cm2 V−1s−1 (the highest 0.47 cm2 V−1s−1) and on/off ratio exceeding 105. In addition, our single crystal arrays also show a very high photoswitch performance with an on/off current ratio up to 4.1 × 105, which is one of the highest values reported for organic materials. It is believed that this method provides a new way to fabricate single crystal arrays and has the potential for application to large area organic electronics. PMID:26282460

  5. Quick Fabrication of Large-area Organic Semiconductor Single Crystal Arrays with a Rapid Annealing Self-Solution-Shearing Method.

    PubMed

    Li, Yunze; Ji, Deyang; Liu, Jie; Yao, Yifan; Fu, Xiaolong; Zhu, Weigang; Xu, Chunhui; Dong, Huanli; Li, Jingze; Hu, Wenping

    2015-08-18

    In this paper, we developed a new method to produce large-area single crystal arrays by using the organic semiconductor 9, 10-bis (phenylethynyl) anthracene (BPEA). This method involves an easy operation, is efficient, meets the demands of being low-cost and is independent of the substrate for large-area arrays fabrication. Based on these single crystal arrays, the organic field effect transistors exhibit the superior performance with the average mobility extracting from the saturation region of 0.2 cm(2) V(-1)s(-1) (the highest 0.47 cm(2) V(-1)s(-1)) and on/off ratio exceeding 10(5). In addition, our single crystal arrays also show a very high photoswitch performance with an on/off current ratio up to 4.1 × 10(5), which is one of the highest values reported for organic materials. It is believed that this method provides a new way to fabricate single crystal arrays and has the potential for application to large area organic electronics.

  6. Multiphoton harvesting metal-organic frameworks

    NASA Astrophysics Data System (ADS)

    Quah, Hong Sheng; Chen, Weiqiang; Schreyer, Martin K.; Yang, Hui; Wong, Ming Wah; Ji, Wei; Vittal, Jagadese J.

    2015-08-01

    Multiphoton upconversion is a process where two or more photons are absorbed simultaneously to excite an electron to an excited state and, subsequently, the relaxation of electron gives rise to the emission of a photon with frequency greater than those of the absorbed photons. Materials possessing such property attracted attention due to applications in biological imaging, photodynamic therapy, three-dimensional optical data storage, frequency-upconverted lasing and optical power limiting. Here we report four-photon upconversion in metal-organic frameworks containing the ligand, trans, trans-9,10-bis(4-pyridylethenyl)anthracene. The ligand has a symmetrical acceptor-π-donor-π-acceptor structure and a singlet biradical electronic ground state, which boosted its multiphoton absorption cross-sections. We demonstrate that the upconversion efficiency can be enhanced by Förster resonance energy transfer within host-guest metal-organic frameworks consisting of encapsulated high quantum yielding guest molecules. Using these strategies, metal-organic framework materials, which can exhibit frequency-upconverted photoluminescence excited by simultaneous multiphoton absorption, can be rationally designed and synthesized.

  7. White organic light-emitting devices with high color purity and stability

    NASA Astrophysics Data System (ADS)

    Bai, Yajie; Liu, Su; Li, Hairong; Liu, Chunjuan; Wang, Jinshun; Chang, Jinxian

    2014-04-01

    A white organic light-emitting device (WOLED) with dual-emitting layers was presented, in which the blue fluorescent dye 2,5,8,11-terta-tertbutylperylene (TBPe) was doped in 2-methyl-9, 10-di(2-naphthyl)-anthracene (MADN) as a blue-emitting layer, while 5,6,11,12-tetraphenylnaphthacene (rubrene, Rb) was doped in the above-mentioned materials as a yellow-emitting layer. The fabricated monochromatic devices using the blue- and yellow-emitting layer have demonstrated that the direct charge trapping mechanism is the dominant emission mechanism in the yellow OLED. Studies on the WOLEDs with dual-emitting layers have shown that the performances of these devices are strongly susceptible to the thickness of the emitting layer and the stack order of two emitting layers. Structure of ITO(160 nm)/NPB(30 nm)/MADN: 5 wt%TBPe: 3 wt%Rb(10 nm)/MADN: 5 wt%TBPe(20 nm)/BCP (10 nm)/Alq3(20 nm)/Al(100 nm) was determined to be the most favorable WOLED. The maximum luminance of 16 000 cd cm-2 at the applied voltage of 13.4 V and Commission International de 1‧Eclairage (CIE) coordinates of (0.3263, 0.3437) which is closer to the standard white light (CIE (0.33, 0.33)) than the most recent reported WOLEDs were obtained. Moreover, there is just slight variation of CIE coordinates (ΔCIEx, y = 0.0171, 0.0167; corresponding Δu‧v‧ = 0.0119) when the current density increases from 10 to 100 mA cm-2. It reveals that the emissive dopant Rb acts as charge traps to improve electron-hole balance, provides sites for electron-hole recombination and thus makes carriers distribute more evenly in the dual-emitting layers which broaden the recombination zone and improve the stability of the CIE coordinates.

  8. Synthesis and high-throughput characterization of structural analogues of molecular glassformers: 1,3,5-trisarylbenzenes.

    PubMed

    Liu, Tianyi; Cheng, Kevin; Salami-Ranjbaran, Elmira; Gao, Feng; Glor, Ethan C; Li, Mu; Walsh, Patrick J; Fakhraai, Zahra

    2015-10-14

    We report the synthesis and characterization of an analogous series of small organic molecules derived from a well-known glass former, 1,3-bis(1-naphthyl)-5-(2-naphthyl)benzene (α,α,β-TNB). Synthesized molecules include α,α,β-TNB, 3,5-di(naphthalen-1-yl)-1-phenylbenzene (α,α-P), 9-(3,5-di(naphthalen-1-yl)phenyl)anthracene (α,α-A), 9,9'-(5-(naphthalen-2-yl)-1,3-phenylene)dianthracene (β-AA) and 3,3',5,5'-tetra(naphthalen-1-yl)-1,1'-biphenyl (α,α,α,α-TNBP). The design of molecules was based on increasing molecular weight with varied π-π interactions in one or more substituents. The synthesis is based on Suzuki cross-coupling of 1-bromo-3-chloro-5-iodobenzene with arylboronic acids, which allows attachment of various substituents to tailor the chemical structure. The bulk compounds were characterized using NMR spectroscopy and differential scanning calorimetry (DSC). Thin films of these compounds were produced using physical vapor deposition and were subsequently annealed above the glass transition temperatures (Tg). For each molecular glass, cooling rate-dependent glass transition temperature measurements (CR-Tg) were performed using ellipsometry as a high-throughput method to characterize thin film properties. CR-Tg allows rapid characterization of glassy properties, such as Tg, apparent thermal expansion coefficients, apparent activation energy at Tg and fragility. DSC measurements confirmed the general trend that increasing molecular weight leads to increasing melting point (Tm) and Tg. Furthermore, CR-Tg provided evidence that the introduction of stronger π-interacting substituents in the chosen set of structural analogues increases fragility and decreases the ability to form glasses, such that β-AA has the largest fragility and highest tendency to crystallize among all the compounds. These strong interactions also significantly elevate Tg and promote more harmonic intermolecular potentials, as observed by decreasing value of the apparent

  9. The effect of chemical structure on the stability of physical vapor deposited glasses of 1,3,5-triarylbenzene.

    PubMed

    Liu, Tianyi; Cheng, Kevin; Salami-Ranjbaran, Elmira; Gao, Feng; Li, Chen; Tong, Xiao; Lin, Yi-Chih; Zhang, Yue; Zhang, William; Klinge, Lindsey; Walsh, Patrick J; Fakhraai, Zahra

    2015-08-28

    We detail the formation and properties associated with stable glasses (SG) formed by a series of structural analogues of 1,3-bis(1-naphthyl)-5-(2-naphthyl)benzene (α,α,β-TNB), a well-studied SG former. Five compounds with similar structural properties were synthesized and physical vapor-deposited with a constant deposition rate at various substrate temperatures (Tdep) in the range between 0.73 Tg and 0.96 Tg. These molecules include α,α,β-TNB, 3,5-di(naphthalen-1-yl)-1-phenylbenzene (α,α-P), 9-(3,5-di(naphthalen-1-yl)phenyl)anthracene (α,α-A), 9,9'-(5-(naphthalen-2-yl)-1,3-phenylene)dianthracene (β-AA), and 3,3',5,5'-tetra(naphthalen-1-yl)-1,1'-biphenyl (α,α,α,α-TNBP). Ellipsometry was used to study the transformations from the as-deposited glasses into ordinary glasses (OG). The stability of each film was evaluated by measuring the fictive temperature (Tf) and density difference between the as-deposited glass and OG. It is demonstrated that all five molecules can form SGs upon vapor deposition in this temperature range. In-depth studies on the dependence of the stability of as-deposited glasses upon Tdep were performed with three molecules, α,α,β-TNB, α,α-P, and α,α-A. The general trends of stability were comparable at the same Tdep/Tg for these three compounds. Similar to previous studies on α,α,β-TNB, vapor-deposited glasses of α,α-P and α,α-A formed the most stable structures around Tdep = 0.8-0.85 Tg. The most stable glass of each molecule showed the lowest thermal expansion coefficient compared to OG and a positive optical birefringence. However, the SGs of α,α-A were less stable compared to α,α-P and α,α,β-TNB at the relative Tdep/Tg. Based on Arrhenius extrapolation of the aging time, as a measure of stability, the most stable α,α-A glass was only aged for a few years as opposed to hundreds or thousands of years for other glasses. We hypothesize that the reduced stability is due to slower mobility at the free surface of

  10. 40 CFR 464.31 - Specialized definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-benzanthracene) 76. chrysene 77. acenaphthylene 78. anthracene 80. fluorene 81. phenanthrene 84. pyrene (3...-benzanthracene) 76. chrysene 77. acenaphthylene 78. anthracene 80. fluorene 81. phenanthrene 84. pyrene (5)...

  11. 40 CFR 464.31 - Specialized definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-benzanthracene) 76. chrysene 77. acenaphthylene 78. anthracene 80. fluorene 81. phenanthrene 84. pyrene (3...-benzanthracene) 76. chrysene 77. acenaphthylene 78. anthracene 80. fluorene 81. phenanthrene 84. pyrene (5)...

  12. Protective effect of Ocimum sanctum on 3-methylcholanthrene, 7,12-dimethylbenz(a)anthracene and aflatoxin B1 induced skin tumorigenesis in mice

    SciTech Connect

    Rastogi, Shipra; Shukla, Yogeshwer; Paul, Bhola N.; Chowdhuri, D. Kar; Khanna, Subhash K.; Das, Mukul

    2007-11-01

    A study on the protective effect of alcoholic extract of the leaves of Ocimum sanctum on 3-mthylcholanthrene (MCA), 7,12-dimethylbenzanthracene (DMBA) and aflatoxin B{sub 1} (AFB{sub 1}) induced skin tumorigenesis in a mouse model has been investigated. The study involved pretreatment of mice with the leaf extract prior to either MCA application or tetradecanoyl phorbol acetate (TPA) treatment in a two-stage tumor protocol viz a viz, DMBA/TPA and AFB1/TPA. The results of the present study indicate that the pretreatment with alcoholic extract of the leaves of O. sanctum decreased the number of tumors in MCA, DMBA/TPA and AFB1/TPA treated mice. The skin tumor induced animals pretreated with alcoholic extract led to a decrease in the expression of cutaneous {gamma}-glutamyl transpeptidase (GGT) and glutathione-S-transferase-P (GST-P) protein. The histopathological examination of skin tumors treated with leaf extract showed increased infiltration of polymorphonuclear, mononuclear and lymphocytic cells, decreased ornithine decarboxylase activity with concomitant enhancement of interleukin-1{beta} (IL-1{beta}) and tumor necrosis factor-{alpha} (TNF-{alpha}) in the serum, implying the in vivo antiproliferative and immunomodulatory activity of leaf extract. The decrease in cutaneous phase I enzymes and elevation of phase II enzymes in response to topical application of leaf extract prior to MCA, AFB1, DMBA/TPA and AFB1/TPA treatment indicate the possibility of impairment in reactive metabolite(s) formation and thereby reducing skin carcinogenicity. Furthermore, pretreatment of leaf extract in the carcinogen induced animals resulted in elevation of glutathione levels and decrease in lipid peroxidation along with heat shock protein expression, indicating a scavenging or antioxidant potential of the extract during chemical carcinogenesis. Thus it can be concluded that leaf extract of O. sanctum provides protection against chemical carcinogenesis in one or more of the following mechanisms: (i) by acting as an antioxidant; (ii) by modulating phase I and II enzymes; (iii) by exhibiting antiproliferative activity.

  13. Strain Differences in Dimethylbenz[a]anthracene-Induced Mammary Tumor Incidence in Long Evans and Sprague Dawley Rat Offspring Following Prenatal Atrazine Exposure

    EPA Science Inventory

    It has been shown that prenatal exposure to the chlorotriazine herbicide atrazine (ATR) during mammary bud outgrowth (late gestation) delays postnatal mammary epithelial progression in Long Evans (LE) rats. Our laboratory has recently found that prenatal exposure to ATR also effe...

  14. Influence of dietary protein intakes on the metabolism and DNA-binding of 7,12-dimethylbenz(a)anthracene (DMBA) in rat mammary epithelial cells

    SciTech Connect

    Singletary, K.; Milner, J.

    1986-03-05

    The influence of prior dietary protein intakes in rats on the ability of their isolated mammary cells to metabolize DMBA to intermediates that bind to intracellular DNA was examined. Female 40d old SD rats (30) were pair-fed isocaloric diets containing 7.5 or 15% protein (casein) for two weeks prior to sacrifice. Pooled cells were plated (0.9 mg protein) in Dulbecco's Modified Eagle's Medium containing antibiotics, insulin and 10% fetal calf serum, 1 h before adding 0.4 ..mu..g DMBA/ml. At 6 hours of incubation, cells from rats fed 15% protein metabolized 52.7% of the DMBA while those from rats fed 7.5% protein metabolized 43.7%. Extracellular water-soluble metabolites increased as dietary protein increased but accounted for only 14% of total metabolism. Binding of DMBA at 6 h to DNA from rats fed 15% protein was 19% higher than binding in rats fed 7.5% protein. These differences in binding increased with increasing doses of DMBA. The increased binding was associated with a proportional increase in both syn and anti- bay-region dihydrodiol-epoxide adducts. The bay-region syn-dihydrodiol-epoxide:deoxyadenosine adduct was the predominant adduct. Thus, increasing dietary protein intake leads to increased metabolism of DMBA and increased binding of bay-region dihydrodiol-epoxides to DNA.

  15. Influence of selenium, age and dosage of 7,12-dimethylbenz(a)anthracene (DMBA) on the in vivo formation of DNA adducts in mammary tissue

    SciTech Connect

    Jinzhou Liu; Milner, J.A. )

    1991-03-15

    Diets formulated to contain selenium, as sodium selenite, 0.1 or 2 {mu}g/g were fed for 2 weeks prior to DMBA treatment. Food intake and weight gain were not influenced by Se intake. Anti- and syn-dihydrodiol epoxide adducts reached maximum binding by 24 h. Se supplementation inhibited by about 50% the appearance of both anti-and syn- DMBA-DNA adducts. Dietary selenium increased the rate of removal of the anti-dihydrodiol epoxide adduct bound to guanine, but delayed the removal of the other adducts. The occurrence of DMBA-DNA adducts correlated positively with the dosage of DMBA administered. Binding increased about 40% as the rat's age increased from 36 to 125 d. Se supplementation inhibited binding in 36, 54 and 125 d old rats. These data confirmed that dietary selenium is effective in inhibiting in vivo metabolism of DMBA.

  16. Di-μ-chlorido-bis­({9-[(2,6-diisopropyl­phen­yl)imino­meth­yl]anthracen-1-yl}palladium(II))

    PubMed Central

    Zhou, Jin; Wang, Qibao; Sun, Hongjian

    2008-01-01

    The centrosymmetric title compound, [Pd2Cl2(C27H26N)2], was obtained by a C—H bond-activation reaction of a Schiff base ligand with Li2PdCl4 in methanol, and was crystallized from dichloro­methane as orange crystals. The Pd atom displays a slightly distorted square-planar geometry, with the N- and C-atom donors in a cis arrangement. PMID:21202224

  17. 9,10-Dihydr­oxy-4,4-dimethyl-5,8-dihydro­anthracen-1(4H)-one

    PubMed Central

    Ramírez-Rodríguez, Oney; Martínez-Cifuentes, Maximiliano; Ibañez, Andres; Vega, Andrés; Araya-Maturana, Ramiro

    2008-01-01

    In the title mol­ecule, C16H16O3, the ring system is planar and an intramolecular hydrogen bond is present. The mol­ecular packing is dominated by an inter­molecular hydrogen bond and by π-stacking inter­actions [inter­planar separation 3.8012 Å]. PMID:21202942

  18. Morphological changes in the lingual papillae and their connective tissue cores on the 7,12-dimethylbenz[alpha]anthracene (DMBA) stimulated rat experimental model.

    PubMed

    Zheng, Jinhua; Xie, Liping; Teng, He; Liu, Shilong; Yoshimura, Ken; Kageyama, Ikuo; Kobayashi, Kan

    2009-02-01

    The aim of the study was to analyze morphological changes of the epithelial surface and underlying connective tissue cores (CTCs) of the lingual mucosa in the rat using a DMBA induced pre-cancerous experimental model. Lightmicroscopically, initially DMBA treated sections exhibited infiltration of chronic inflammatory cells. At 16 weeks, aldehyde-fuchsin (AF) positive elastic fibers decreased and were scanty in the juxtaepithelium. On the other hand, rather densely packed thick bundles of AF positive fibers were observable in the deep layers of lamina propria. Carcinomas were not found at any stage, however, epithelial dysplasia was observed at 24 weeks post-treatment with DMBA. Scanning electron microscopy revealed an irregular arrangement of filiform papillae 4-12 weeks following DMBA stimulation. Patchy degenerated areas were observed especially at 16-24 weeks post-treatment and filiform papillae were totally attenuated on the central part of the degenerated areas. After removal of the epithelium, attenuated CTCs were observed from 4-8 weeks. Morphology of CTCs seemed to be gradually remodeled and severely altered in the later stage. The CTCs were however attenuated and exhibited a patchy distribution. The animal experimental model in this study revealed degenerative morphological changes of CTCs of the lingual papillae in the precancerous stage induced by DMBA.

  19. A Rare and Exclusive Endoperoxide Photoproduct Derived from a Thiacalix[4]arene Crown-Shaped Derivative Bearing a 9,10-Substituted Anthracene Moiety.

    PubMed

    Zhao, Jiang-Lin; Wu, Chong; Tomiyasu, Hirotsugu; Zeng, Xi; Elsegood, Mark R J; Redshaw, Carl; Yamato, Takehiko

    2016-05-20

    A rare and exclusive endoperoxide photoproduct was quantitatively obtained from a thiacalix[4]arene crown-shaped derivative upon irradiation at λ=365 nm; the structure was unambiguously confirmed by (1) H/(13) C NMR spectroscopy and X-ray crystallography. The prerequisites for the formation of the endoperoxide photoproduct have also been discussed. Furthermore, the photochemical reaction rate could be greatly enhanced in the presence of the thiacalix[4]arene platform because it served as a host to capture oxygen.

  20. Vertical Single-Crystalline Organic Nanowires on Graphene: Solution-Phase Epitaxy and Optical Microcavities.

    PubMed

    Zheng, Jian-Yao; Xu, Hongjun; Wang, Jing Jing; Winters, Sinéad; Motta, Carlo; Karademir, Ertuğrul; Zhu, Weigang; Varrla, Eswaraiah; Duesberg, Georg S; Sanvito, Stefano; Hu, Wenping; Donegan, John F

    2016-08-10

    Vertically aligned nanowires (NWs) of single crystal semiconductors have attracted a great deal of interest in the past few years. They have strong potential to be used in device structures with high density and with intriguing optoelectronic properties. However, fabricating such nanowire structures using organic semiconducting materials remains technically challenging. Here we report a simple procedure for the synthesis of crystalline 9,10-bis(phenylethynyl) anthracene (BPEA) NWs on a graphene surface utilizing a solution-phase van der Waals (vdW) epitaxial strategy. The wires are found to grow preferentially in a vertical direction on the surface of graphene. Structural characterization and first-principles ab initio simulations were performed to investigate the epitaxial growth and the molecular orientation of the BPEA molecules on graphene was studied, revealing the role of interactions at the graphene-BPEA interface in determining the molecular orientation. These free-standing NWs showed not only efficient optical waveguiding with low loss along the NW but also confinement of light between the two end facets of the NW forming a microcavity Fabry-Pérot resonator. From an analysis of the optical dispersion within such NW microcavities, we observed strong slowing of the waveguided light with a group velocity reduced to one-tenth the speed of light. Applications of the vertical single-crystalline organic NWs grown on graphene will benefit from a combination of the unique electronic properties and flexibility of graphene and the tunable optical and electronic properties of organic NWs. Therefore, these vertical organic NW arrays on graphene offer the potential for realizing future on-chip light sources. PMID:27438189

  1. Aggregation-induced emission: a simple strategy to improve chemiluminescence resonance energy transfer.

    PubMed

    Zhang, Lijuan; He, Nan; Lu, Chao

    2015-01-20

    The emergence of aggregation-induced emission (AIE) has opened up a new avenue for scientists. There is a great demand for the development of a new generation chemiluminescence resonance energy transfer (CRET) acceptors with AIE characteristics due to the aggregation-caused chemiluminescence (CL) quenching effect commonly observed in the conventional fluorophore CL acceptors at high concentrations. However, the systematical studies involving in AIE-amplified CL are still scarce. Herein, it is the first report that the gold nanocluster aggregates (a type of well-defined AIE molecules) are used to study their influence on the bis(2,4,6-trichlorophenyl) oxalate (TCPO)-H2O2 CL reaction. Interestingly, the AIE molecules in the diluted solution are unable to boost the CL signal of the TCPO-H2O2 system, but their aggregates display a strongly enhanced CL emission compared to their counterparts of fluorophore molecules, thanks to the unique AIE effect of gold nanoclusters. In comparison to rhodamine B with the aid of an imidazole catalyst, the detection limit of the gold nanocluster aggregate-amplified CL probe for H2O2 (S/N = 3) is low in the absence of any catalyst. Finally, the other two typical AIE molecules, Au(I)-thiolate complexes and 9,10-bis[4-(3-sulfonatopropoxyl)-styryl]anthracene (BSPSA), are investigated to verify the generality of the AIE molecule-amplified CL emissions. These results demonstrate effective access to highly fluorescent AIE molecules with practical applications in avoiding the aggregation-induced CL quenching at high concentrations, which can be expected to provide a novel and sensitive platform for the CL amplified detection.

  2. Charge transport and injection in amorphous organic electronic materials

    NASA Astrophysics Data System (ADS)

    Tse, Shing Chi

    This thesis presents how we use various measuring techniques to study the charge transport and injection in organic electronic materials. Understanding charge transport and injection properties in organic solids is of vital importance for improving performance characteristics of organic electronic devices, including organic-light-emitting diodes (OLEDs), photovoltaic cells (OPVs), and field effect transistors (OFETs). The charge transport properties of amorphous organic materials, commonly used in organic electronic devices, are investigated by the means of carrier mobility measurements. Transient electroluminescence (EL) technique was used to evaluate the electron mobility of an electron transporting material--- tris(8-hydroxyquinoline) aluminum (Alq3). The results are in excellent agreement with independent time-of-flight (TOF) measurements. Then, the effect of dopants on electron transport was also examined. TOF technique was also used to examine the effects of tertiary-butyl (t-Bu) substitutions on anthracene derivatives (ADN). All ADN compounds were found to be ambipolar. As the degree of t-Bu substitution increases, the carrier mobilities decrease progressively. The reduction of carrier mobilities with increasing t-butylation can be attributed to a decrease in the charge-transfer integral or the wavefunction overlap. In addition, from TOF measurements, two naphthylamine-based hole transporters, namely, N,N'-diphenyl-N,N'-bis(1-naphthyl)(1,1'-biphenyl)-4,4'diamine (NPB) and 4,4',4"-tris(n-(2-naphthyl)-n-phenyl-amino)-triphenylamine (2TNATA) were found to possess electron-transporting (ET) abilities. An organic light-emitting diode that employed NPB as the ET material was demonstrated. The electron conducting mechanism of NPB and 2TNATA in relation to the hopping model will be discussed. Furthermore, the ET property of NPB applied in OLEDs will also be examined. Besides transient EL and TOF techniques, we also use dark-injection space-charge-limited current

  3. 40 CFR Appendix II to Part 258 - List of Hazardous Inorganic and Organic Constituents

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-Aminobiphenyl 92-67-1 -4-amine Anthracene 120-12-7 Anthracene Antimony (Total) Antimony Arsenic (Total) Arsenic..., ethyl- Ethyl methacrylate 97-63-2 2-Propenoic acid, 2-methyl-, ethyl ester Ethyl methanesulfonate...

  4. 40 CFR 464.21 - Specialized definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... benzo(a)anthracene (1,2-benzanthracene) 74. 3,4-benzofluoranthene 75. benzo(k) fluoranthene 76. chrysene.... benzo(a)anthracene (1,2-benzanthracene) 74. 3,4-benzofluoranthene 75. benzo(k) fluoranthene 76. chrysene.... chrysene 77. acenaphthylene 78. anthracene 81. phenanthrene 84. pyrene (5) Mold Cooling (§ 464.25(g)...

  5. 40 CFR 464.21 - Specialized definitions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... benzo(a)anthracene (1,2-benzanthracene) 74. 3,4-benzofluoranthene 75. benzo(k) fluoranthene 76. chrysene.... benzo(a)anthracene (1,2-benzanthracene) 74. 3,4-benzofluoranthene 75. benzo(k) fluoranthene 76. chrysene.... chrysene 77. acenaphthylene 78. anthracene 81. phenanthrene 84. pyrene (5) Mold Cooling (§ 464.25(g)...

  6. 40 CFR 464.21 - Specialized definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... benzo(a)anthracene (1,2-benzanthracene) 74. 3,4-benzofluoranthene 75. benzo(k) fluoranthene 76. chrysene.... benzo(a)anthracene (1,2-benzanthracene) 74. 3,4-benzofluoranthene 75. benzo(k) fluoranthene 76. chrysene.... chrysene 77. acenaphthylene 78. anthracene 81. phenanthrene 84. pyrene (5) Mold Cooling (§ 464.25(g)...

  7. Translational diffusion in sucrose benzoate near the glass transition: Probe size dependence in the breakdown of the Stokes-Einstein equation

    NASA Astrophysics Data System (ADS)

    Rajian, Justin Rajesh; Quitevis, Edward L.

    2007-06-01

    The translational diffusion coefficient Dtrans for rubrene, 9,10-bis(phenylethynyl)anthracene (BPEA), and tetracene in the fragile molecular glass-former sucrose benzoate (SB) (Tg=337K) was studied as a function of temperature from Tg+3KtoTg+71K by use of the holographic fluorescence recovery after photobleaching technique. The values of Dtrans vary by five to six orders of magnitude in this temperature range. Contrary to the predictions of the Stokes-Einstein equation, the temperature dependence of probe diffusion in SB over the temperature range of the measurements is weaker than that of T /η, where η is the shear viscosity. In going from the crossover temperature Tx≈1.2Tg to Tg, Dtransη/T increases by factors of 2.4±0.2 decades for rubrene, 3.4±0.2 decades for BPEA, and 3.8±0.4 decades for tetracene. The decoupling between probe diffusion in SB and viscosity is characterized by the scaling law Dtrans˜T/ηξ, with ξ =0.621 for tetracene, 0.654 for BPEA, and 0.722 for rubrene. Data for probe diffusion in SB are combined with data from the literature for probe diffusion in ortho-terphenyl and ααβ-tris(naphthyl)benzene in a plot of enhancement versus the relative probe size parameter ρm=(mp/mh)1/3, where mp and mh are, respectively, the molecular weights of the probe and host solvent. The plot clearly shows a sharp increase in enhancement of translational diffusion at ρm≈1. By applying temperature shifts, Dtrans for probe diffusion in SB and the dielectric relaxation time τD can be superimposed on a single master curve based on the Williams-Landel-Ferry equation. This suggests that the dynamics of probe diffusion in SB is described by the scaling relationship Dtrans˜1/τD(T +ΔT), where τD(T+ΔT) is the temperature-shifted dielectric relaxation time. The results from this study are discussed within the context of dynamic heterogeneity in glass-forming liquids.

  8. Modulatory effect of Ganoderma lucidum on expression of xenobiotic enzymes, oxidant-antioxidant and hormonal status in 7,12-dimethylbenz(a)anthracene-induced mammary carcinoma in rats

    PubMed Central

    Deepalakshmi, Krishnamoorthy; Mirunalini, Sankaran

    2013-01-01

    Background: Mushrooms are an important natural source represents a major and untapped potent pharmaceutical product. Ganoderma lucidum (G. lucidum) an important medicinal mushroom has been shown to contain high amount of antioxidant. However, in vivo studies on G. lucidum fruiting bodies are lacking. Objectives: To determine the effects of G. lucidum fruiting bodies ethanolic extract (GLEet) on expression of xenobiotic enzymes, oxidant-antioxidant and hormonal status on 7,12-dimethyl benz[a]antheracene (DMBA) induced experimental breast cancer was investigated in female Sprague dawley rats. Materials and Methods: Cancer bearing female Sprague dawley rats was orally treated with GLEet (500mg/kg body weight) for 16 weeks. Incidence and tumor volume in each groups, and biochemical parameters were carried out in plasma, liver, and mammary tissues of animals. Histopathological and immunohistochemical analysis were also determined. Result: Oral administration of GLEet on tumor bearing animals significantly diminished the levels of lipid peroxidation thereby enhancing the nonenzymatic antioxidants and also positively regulated the estrogen receptor hormones level to near normal when compared with DMBA treated rats. Moreover, it also positively modulates the xenobiotic metabolizing enzymes. Therefore, the dietary administration of G. lucidum may be efficiently used as a chemopreventive agent against mammary carcinogenesis. Conclusion: We concluded that G. lucidum is a potent chemopreventive agent, thereby it offers maximum protection against DMBA-induced mammary carcinogenesis. PMID:23772114

  9. Influence of maternal diet enrichment with conjugated linoleic acids on lipoxygenase metabolites of polyunsaturated fatty acids in serum of their offspring with 7,12-dimethylbenz[a]anthracene induced mammary tumors.

    PubMed

    Białek, Agnieszka; Jelińska, Małgorzata; Tokarz, Andrzej

    2015-01-01

    Conjugated linoleic acids (CLA), which are a group of naturally occurring in food isomers of linoleic acid, seem to be active in each step of cancer development. There are many possible mechanisms of this action, and interactions with polyunsaturated fatty acids (PUFA) in lipoxygenase (LOX) and cyclooxygenase (COX) pathways are among the most likely ones. The aim of this study was to assess the influence of diet supplementation with CLA of pregnant and breastfeeding Sprague-Dawley female rats on selected polyunsaturated fatty acids and their LOX metabolites concentrations in serum of the progeny with chemically induced mammary tumors. We confirmed that higher supply of CLA in the diet of female rats corresponded with the lower susceptibility to chemically induced mammary tumors in their female offspring. It also influenced the polyunsaturated n-3 and n-6 fatty acid concentrations in serum, as well as the concentrations of their LOX metabolites. The significant negative correlation between the concentrations of two CLA isomers in serum and linoleic acid (p=0.0144, p=0.0098), eicosapentaenoic acid (p=0.0158, p=0.0124), and 5-HEPE (p=0.0014, p=0.01690) and between cis-9, trans-11 CLA and 15-HEPE was detected, whereas arachidonic acid concentration positively correlated with CLA concentration in serum (p=0.0150, p=0.0231). Our results indicate that CLA can compete with PUFA and influence serum concentration of PUFA and their LOX metabolites, which could partly explain the anticancerogenic action of CLA.

  10. 6-[3-(2,4-Dimethyl-anilino)-2-hydroxy-prop-oxy]-1,8-dihydr-oxy-3-methyl-9,10-dihydro-anthracene-9,10-dione.

    PubMed

    Wang, Xing-Po; Xu, Wenfang

    2009-01-23

    In the title compound, C(26)H(25)NO(6), the anthraquinone ring system forms a dihedral angle of 15.5 (1)° with the benzene ring of the dimethyl-aniline group. Intra-molecular O-H⋯O hydrogen bonding is observed between the carbonyl and two hydroxyl groups. The mol-ecules are linked into a ribbon-like structure along the [100] direction by O-H⋯N and C-H⋯O hydrogen bonds. The crystal used was twinned via a 180° rotation about [100]. The ratio of the two twin components is 0.947 (1):0.053 (1).

  11. Reduction in 7,12-dimethylbenz[a]anthracene-induced hepatic cytochrome-P450 1A1 expression following soy consumption in female rats is mediated by degradation of the aryl hydrocarbon receptor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Consumption of a soy diet has been found to reduce cancer incidence in animals and is associated with reduced cancer risk in humans. In this study, the effect of consuming soy protein isolate (SPI) on the aryl hydrocarbon receptor (AhR)-mediated signaling pathway was investigated. Female Sprague-Daw...

  12. Determination of the effective redox potentials of SmI₂, SmBr₂, SmCl₂, and their complexes with water by reduction of aromatic hydrocarbons. Reduction of anthracene and stilbene by samarium(II) iodide-water complex.

    PubMed

    Szostak, Michal; Spain, Malcolm; Procter, David J

    2014-03-21

    Samarium(II) iodide-water complexes are ideally suited to mediate challenging electron transfer reactions, yet the effective redox potential of these powerful reductants has not been determined. Herein, we report an examination of the reactivity of SmI2(H2O)n with a series of unsaturated hydrocarbons and alkyl halides with reduction potentials ranging from -1.6 to -3.4 V vs SCE. We found that SmI2(H2O)n reacts with substrates that have reduction potentials more positive than -2.21 V vs SCE, which is much higher than the thermodynamic redox potential of SmI2(H2O)n determined by electrochemical methods (up to -1.3 V vs SCE). Determination of the effective redox potential demonstrates that coordination of water to SmI2 increases the effective reducing power of Sm(II) by more than 0.4 V. We demonstrate that complexes of SmI2(H2O)n arising from the addition of large amounts of H2O (500 equiv) are much less reactive toward reduction of aromatic hydrocarbons than complexes of SmI2(H2O)n prepared using 50 equiv of H2O. We also report that SmI2(H2O)n cleanly mediates Birch reductions of substrates bearing at least two aromatic rings in excellent yields, at room temperature, under very mild reaction conditions, and with selectivity that is not attainable by other single electron transfer reductants.

  13. Prenatal 3,3',4,4',5-pentachlorobiphenyl exposure modulates induction of rat hepatic CYP 1A1, 1B1, and AhR by 7,12-dimethylbenz[a]anthracene

    SciTech Connect

    Wakui, Shin . E-mail: wakui@azabu-u.ac.jp; Yokoo, Kiyofumi; Takahashi, Hiroyuki; Muto, Tomoko; Suzuki, Yoshihiko; Kanai, Yoshikatsu; Hano, Hiroshi; Furusato, Masakuni; Endou, Hitoshi

    2006-02-01

    We previously reported the finding that prenatal exposure to a relatively low dose of PCB126 increases the rate of DMBA-induced rat mammary carcinoma, while a high dose decreased it. One of the most important factors determining the sensitivity to mammary carcinogenesis is the metabolic stage at administration of the carcinogenic agent. DMBA is a procarcinogen that recruits the host metabolism to yield its ultimate carcinogenic form, and CYP1A1 and CYP1B1 (CYP1) conduct this metabolism. We investigated the hepatic expression of CYP1 and AhR following oral administration of DMBA (100 mg/kg b.w.) (i.g.) to 50-day-old female Sprague-Dawley rats whose dams had been treated (i.g.) with 2.5 ng, 250 ng, 7.5 {mu}g of PCB126/kg or the vehicle on days 13 to 19 post-conception. Real-time quantitative RT-PCR analysis revealed that the prenatal exposure to a relatively low dose of PCB126 (the 250 ng group) prolonged the higher expression of CYP1A1, CYP1B1, and AhR mRNA, while prenatal exposure to a high dose of PCB126 (the 7.5 {mu}g group) prolonged the higher expression of CYP1A1 and AhR mRNA. Western blotting and immunohistochemical analyses were consistent with mRNAs changes. Because DMBA oxidation produces a highly mutagenic metabolite and is finally catalyzed by CYP1B1, a relatively low PCB126 dose might produce the biological character to potentially increase the risk of DMBA-induced mammary carcinoma.

  14. Structure-activity relationships among the ortho-, meta- and para-isomers of phenylenebis (methylene)seleno cyanate (XSC) as inhibitors of 7,12-dimethylbenz(a)anthracene-DNA binding in mammary glands of female CD rats.

    PubMed

    Chae, Y; Upadhyaya, P; Elbayoumy, K

    1997-01-01

    As shown earlier p-XSC inhibits DMBA-induced mammary cancer in female CD rats. This inhibition is due, in part, to inhibition of DMBA-DNA adduct formation in the target organ. We have now utilized the DMBA-DNA binding assay to evaluate the chemopreventive potential of positional isomers of XSC (o-, m- and p-XSC) applied at selenium doses of 5 and 15 ppm; p-XTC, the sulfur analog of p-XSC, was used at an equimolar dose to determine whether selenium is required for the observed inhibitory effect. Selenium and sulfur compounds were administered in a semipurified high-fat diet (23.5% corn oil). Rats were fed for 1 week prior to oral administration of a single dose of [H-3]DMBA (5 mg/rat); animals were sacrificed 24 h later, DNA was isolated from mammary fat pads and levels of total binding were determined. All agents produced a dose-dependent inhibition of DMBA-DNA binding in the mammary tissues. The inhibition at 5, respectively 15 ppm Se in the form of XSC isomers and at 30 mu M, respectively 90 mu M in the form of p-XTC was: o-XSC (27%, 42%); m-XSC (32%, 47%); p-XSC (22%, 29%); and p-XTC (10%, 20%); only inhibition by dietary o-XSC and m-XSC at 15 ppm Se reached statistical significance (p<0.05). Thus, o-XSC and m-XSC equally inhibit DMBA-DNA binding and both are better inhibitors than p-XSC; the latter appears to be slightly more effective than its sulfur analog p-XTC. Clearly, the structure of the selenium-containing compound is a critical factor in determining the extent of inhibition of DMBA-DNA binding. The described short-term in vivo assay may constitute the basis for future selection of chemopreventive agents in the rat mammary tumor model system.

  15. In vivo DNA/RNA adduction of 7,12-dimethylbenz(a)anthracene (DMBA) and benzo(a)pyrene (BaP) in the liver of rainbow trout (Oncorhynchus mykiss)

    SciTech Connect

    Schnitz, A.R.; O'Connor, J.M. )

    1992-07-01

    Juvenile rainbow trout were exposed via two intramuscular injections to either 14C-DMBA for 24 hr or 14C-BaP for 48 hr, after which the livers were removed for DNA extraction and analysis. In the fish exposed to 14C-BaP, 0.2 ng was bound to the DNA, representing 0.5% of the total liver PAH-derived radioactivity and 2.38% of the administered dose. Liver DNA and RNA were found to contain 0.5% of the administered dose, respectively. Liver analysis of rainbow trout exposed to 14C-DMBA demonstrated that 0.4 ng and 0.3 ng were bound to the DNA and RNA, respectively. This represents 1.0% and 0.6% of the liver DMBA burden, respectively. The DNA adduct concentrations formed were comparable to both in vitro and in vivo experiments with both mammals and fishes, indicating that relatively small, environmentally realistic' doses of PAH have the ability to bind significantly to critical cellular macromolecules of young fish in vivo.

  16. Quinoxaline-substituted chalcones as new inhibitors of breast cancer resistance protein ABCG2: polyspecificity at B-ring position.

    PubMed

    Winter, Evelyn; Gozzi, Gustavo Jabor; Chiaradia-Delatorre, Louise Domeneghini; Daflon-Yunes, Nathalia; Terreux, Raphael; Gauthier, Charlotte; Mascarello, Alessandra; Leal, Paulo César; Cadena, Silvia M; Yunes, Rosendo Augusto; Nunes, Ricardo José; Creczynski-Pasa, Tania Beatriz; Di Pietro, Attilio

    2014-01-01

    A series of chalcones substituted by a quinoxaline unit at the B-ring were synthesized and tested as inhibitors of breast cancer resistance protein-mediated mitoxantrone efflux. These compounds appeared more efficient than analogs containing other B-ring substituents such as 2-naphthyl or 3,4-methylenedioxyphenyl while an intermediate inhibitory activity was obtained with a 1-naphthyl group. In all cases, two or three methoxy groups had to be present on the phenyl A-ring to produce a maximal inhibition. Molecular modeling indicated both electrostatic and steric positive contributions. A higher potency was observed when the 2-naphthyl or 3,4-methylenedioxyphenyl group was shifted to the A-ring and methoxy substituents were shifted to the phenyl B-ring, indicating preferences among polyspecificity of inhibition.

  17. Ground state of naphthyl cation: Singlet or triplet?

    SciTech Connect

    Dutta, Achintya Kumar; Vaval, Nayana Pal, Sourav; Manohar, Prashant U.

    2014-03-21

    We present a benchmark theoretical investigation on the electronic structure and singlet-triplet(S-T) gap of 1- and 2-naphthyl cations using the CCSD(T) method. Our calculations reveal that the ground states of both the naphthyl cations are singlet, contrary to the results obtained by DFT/B3LYP calculations reported in previous theoretical studies. However, the triplet states obtained in the two structural isomers of naphthyl cation are completely different. The triplet state in 1-naphthyl cation is (π,σ) type, whereas in 2-naphthyl cation it is (σ,σ{sup ′}) type. The S-T gaps in naphthyl cations and the relative stability ordering of the singlet and the triplet states are highly sensitive to the basis-set quality as well as level of correlation, and demand for inclusion of perturbative triples in the coupled-cluster ansatz.

  18. Quinoxaline-substituted chalcones as new inhibitors of breast cancer resistance protein ABCG2: polyspecificity at B-ring position

    PubMed Central

    Winter, Evelyn; Gozzi, Gustavo Jabor; Chiaradia-Delatorre, Louise Domeneghini; Daflon-Yunes, Nathalia; Terreux, Raphael; Gauthier, Charlotte; Mascarello, Alessandra; Leal, Paulo César; Cadena, Silvia M; Yunes, Rosendo Augusto; Nunes, Ricardo José; Creczynski-Pasa, Tania Beatriz; Di Pietro, Attilio

    2014-01-01

    A series of chalcones substituted by a quinoxaline unit at the B-ring were synthesized and tested as inhibitors of breast cancer resistance protein-mediated mitoxantrone efflux. These compounds appeared more efficient than analogs containing other B-ring substituents such as 2-naphthyl or 3,4-methylenedioxyphenyl while an intermediate inhibitory activity was obtained with a 1-naphthyl group. In all cases, two or three methoxy groups had to be present on the phenyl A-ring to produce a maximal inhibition. Molecular modeling indicated both electrostatic and steric positive contributions. A higher potency was observed when the 2-naphthyl or 3,4-methylenedioxyphenyl group was shifted to the A-ring and methoxy substituents were shifted to the phenyl B-ring, indicating preferences among polyspecificity of inhibition. PMID:24920885

  19. Diastereo- and enantioselective iridium-catalyzed allylation of cyclic ketone enolates: synergetic effect of ligands and barium enolates.

    PubMed

    Chen, Wenyong; Chen, Ming; Hartwig, John F

    2014-11-12

    We report asymmetric allylic alkylation of barium enolates of cyclic ketones catalyzed by a metallacyclic iridium complex containing a phosphoramidite ligand derived from (R)-1-(2-naphthyl)ethylamine. The reaction products contain adjacent quaternary and tertiary stereocenters. This process demonstrates that unstabilized cyclic ketone enolates can undergo diastereo- and enantioselective Ir-catalyzed allylic substitution reactions with the proper choice of enolate countercation. The products of these reactions can be conveniently transformed to various useful polycarbocyclic structures.

  20. Fuel composition and method for control of octane requirement increase

    SciTech Connect

    Croudace, M.C.; Wusz, T.; Brass, S.G.

    1987-10-13

    A fuel composition is described comprising a hydrocarbon liquid consisting essentially of components boiling within the gasoline range. An octane requirement is dissolved increase-inhibiting amount or more fused aromatic compounds having aromatic rings containing no heteroatoms in the ring structure selected from the group consisting of acenaphthylene, benzanthracene, naphthalene, anthracene, pheneanthrene, amino anthracene, chrysene, coronene, 1,2,3,4-dibenzanthracene, 1,2,4,6-dibenzanthracene, 9,10-diphenyl anthracene, pentacene, perylene, pyrene, rubrene, and triphenylene.

  1. On the aromatic stabilization of benzenoid hydrocarbons.

    PubMed

    Ciesielski, Arkadiusz; Stepień, Dorota K; Dobrowolski, Michał A; Dobrzycki, Łukasz; Cyrański, Michał K

    2012-10-18

    A general scheme for estimation of aromatic stabilization energies of benzenoid hydrocarbons based on selected topological features has been presented. The reactions have been applied to benzene, naphthalene, anthracene, phenanthrene, pyrene, tetracene, benz[a]anthracene, chrysene, [4]-helicene, anthanthrene and coronene.

  2. Mutagenicity of anthraquinone and hydroxylated anthraquinones in the Ames/Salmonella microsome system.

    PubMed Central

    Liberman, D F; Fink, R C; Schaefer, F L; Mulcahy, R J; Stark, A A

    1982-01-01

    The mutagenicity of anthracene, anthraquinone, and four structurally similar compounds of each was evaluated in the Ames/Salmonella microsome assay. Anthraquinone was shown to be mutagenic for strains TA1537, TA1538, and TA98 in the absence of rat liver homogenate. The four anthraquinone derivatives tested were mutagenic for TA1537 exclusively. None of the anthracenes exhibited mutagenic activity. PMID:7103489

  3. Proliferating conduction by isomerism

    NASA Astrophysics Data System (ADS)

    Kaur, Rupan Preet; Sawhney, Ravinder Singh; Engles, Derick

    2015-01-01

    The electrical conduction of isomers of anthracene molecule attached between two semi-infinite gold electrodes was simulated using extended Huckel theory (EHT)-based on semi-empirical model in this research work. The electron transport parameters were examined in two epochs by buffering anthracene and its isomer phenanthrene alternatively between gold electrodes using sulphur as an alligator clip, under variegated bias voltages. Differential NDR effect was observed in both the cases but phenanthrene exhibited more linear I-V curve than its counterpart, anthracene. The simulated results discovered phenanthrene as a better candidate than anthracene towards contributing to electrical conduction in molecular junctions. Phenanthrene reported maximum conductance of 0.74G0 whereas anthracene exhibited 0.03G0 at 0.8V.

  4. The crystal structures of two chalcones: (2E)-1-(5-chloro­thio­phen-2-yl)-3-(2-methyl­phen­yl)prop-2-en-1-one and (2E)-1-(anthracen-9-yl)-3-[4-(propan-2-yl)phen­yl]prop-2-en-1-one

    PubMed Central

    Girisha, Marisiddaiah; Yathirajan, Hemmige S.; Jasinski, Jerry P.; Glidewell, Christopher

    2016-01-01

    In the crystal of compound (I), C14H11ClOS, mol­ecules are linked by C—H⋯O hydrogen bonds to form simple C(5) chains. Compound (II), C26H22O, crystallizes with Z′ = 2 in space group P-1; one of the mol­ecules is fully ordered but the other is disordered over two sets of atomic sites having occupancies 0.644 (3) and 0.356 (3). The two disordered components differ from one another in the orientation of the isopropyl substituents, and both differ from the ordered mol­ecules in the arrangement of the central propenone spacer unit, so that the crystal of (II) contains three distinct conformers. The ordered and disordered conformers each form a C(8) chain built from a single type of C—H⋯O hydrogen bond but those formed by the disordered conformers differ from that formed by the ordered form. PMID:27536402

  5. Synthesis of [1-.sup.13C]pyruvic acid], [2-.sup.13C]pyruvic acid], [3-.sup.13C]pyruvic acid] and combinations thereof

    DOEpatents

    Martinez, Rodolfo A.; Unkefer, Clifford J.; Alvarez, Marc A.

    2009-09-01

    The present invention is directed to labeled compounds, of the formulae ##STR00001## wherein C* is each independently selected from the group consisting of .sup.13C and .sup.12C with the proviso that at least one C* is .sup.13C, each hydrogen of the methylene group can independently be either hydrogen or deuterium, the methyl group includes either zero or three deuterium atoms, Q is from the group of sulfide, sulfinyl, and sulfone, Z is an aryl group from the group of 1-naphthyl, substituted 1-naphthyl, 2-naphthyl, substituted 2-naphthyl, and phenyl groups with the structure ##STR00002## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are each independently from the group of hydrogen, a C.sub.1-C.sub.4 lower alkyl, a halogen, and an amino group from the group of NH.sub.2, NHR and NRR' where R and R' are each independently from the group of a C.sub.1-C.sub.4 lower alkyl, a phenyl, and an alkoxy group, and the methyl group can include either zero or three deuterium atoms.

  6. Synthesis of [1-.sup.13C]pyruvic acid], [2-.sup.13C]pyruvic acid], [3-.sup.13C]pyruvic acid] and combinations thereof

    DOEpatents

    Martinez, Rodolfo A. , Unkefer; Clifford J. , Alvarez; Marc A.

    2012-06-12

    The present invention is directed to the labeled compounds, ##STR00001## wherein C* is each either .sup.13C and .sup.12C where at least one C* is .sup.13C, each hydrogen of the methylene group is hydrogen or deuterium, the methyl group includes either zero or three deuterium atoms, Q is sulfide, sulfinyl, or sulfone, Z is an aryl group such as 1-naphthyl, substituted 1-naphthyl, 2-naphthyl, substituted 2-naphthyl, or a phenyl group ##STR00002## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are each independently either hydrogen, a C.sub.1-C.sub.4 lower alkyl, a halogen, and an amino group such as NH.sub.2, NHR and NRR' where R and R' are each independently either a C.sub.1-C.sub.4 lower alkyl, a phenyl, and an alkoxy group, and the methyl group can include either zero or three deuterium atoms. The present invention is also directed to the labeled compounds ##STR00003##

  7. Synthesis of [.sup.13C] and [.sup.2H] substituted methacrylic acid, [.sup.13C] and [.sup.2H] substituted methyl methacrylate and/or related compounds

    SciTech Connect

    Alvarez, Marc A.; Martinez, Rodolfo A.; Unkefer, Clifford J.

    2010-02-16

    The present invention is directed to labeled compounds of the formulae ##STR00001## wherein Q is selected from the group consisting of --S(.dbd.O)--, and --S(.dbd.O).sub.2--, Z is selected from the group consisting of 1-naphthyl, substituted 1-naphthyl, 2-naphthyl, substituted 2-naphthyl, and phenyl groups with the structure ##STR00002## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are each independently selected from the group consisting of hydrogen, a C.sub.1-C.sub.4 lower alkyl, a halogen, and an amino group selected from the group consisting of NH.sub.2, NHR and NRR' where R and R' are each independently selected from the group consisting of a C.sub.1-C.sub.4 lower alkyl, an aryl, and an alkoxy group, and X is selected from the group consisting of hydrogen, a C.sub.1-C.sub.4 lower alkyl group, and a fully-deuterated C.sub.1-C.sub.4 lower alkyl group.

  8. Identification of major urinary metabolites of nafarelin acetate, a potent agonist of luteinizing hormone-releasing hormone, in the rhesus monkey

    SciTech Connect

    Chan, R.L.; Chaplin, M.D.

    1985-09-01

    Nafarelin acetate (less than Glu-His-Trp-Ser-Tyr-3-(2-naphthyl)-D-Ala-Leu-Arg-Pro-Gly-NH2) is a potent agonistic analogue of luteinizing hormone-releasing hormone. After a single iv administration of nafarelin acetate (with UC label at C-3 of 3-(2-naphthyl)-D-Ala) to female rhesus monkeys, about 80% of the radioactivity was eliminated in urine. Five major radioactive urinary metabolites were isolated and purified by reversed phase HPLC. Four of these metabolites, identified by amino acid analysis, were short peptides: the 5-10-hexapeptide amide, the 6-10-pentapeptide amide, the 5-7-tripeptide, and the 6-7-dipeptide. The fifth metabolite, which accounted for about 15% of the radioactivity administered, was shown by NMR and mass spectrometry to be 2-naphthylacetic acid. A possible pathway of its formation is by oxidative deamination of 3-(2-napthyl)-D-Ala to give the corresponding alpha-keto acid, followed by oxidative decarboxylation of the alpha-keto acid. These five metabolites together accounted for about 70% of the radioactivity recovered in the urine of rhesus monkeys, or more than half of the radioactivity in the administered dose. Nafarelin acetate was also present in small amounts. Several of these metabolites were also present in plasma of the rhesus monkey.

  9. Synthesis Of [2h, 13c]M [2h2m 13c], And [2h3,, 13c] Methyl Aryl Sulfones And Sulfoxides

    DOEpatents

    Martinez, Rodolfo A.; Alvarez, Marc A.; Silks, III, Louis A.; Unkefer, Clifford J.; Schmidt, Jurgen G.

    2004-07-20

    The present invention is directed to labeled compounds, [.sup.2 H.sub.1, .sup.13 C], [.sup.2 H.sub.2, .sup.13 C] and [.sup.2 H.sub.3, .sup.13 C]methyl aryl sulfones and [.sup.2 H.sub.1, .sup.13 C], [.sup.2 H.sub.2, .sup.13 C] and [.sup.2 H.sub.3, .sup.13 C]methyl aryl sulfoxides, wherein the .sup.13 C methyl group attached to the sulfur of the sulfone or sulfoxide includes exactly one, two or three deuterium atoms and the aryl group is selected from the group consisting of 1-naphthyl, substituted 1-naphthyl, 2-naphthyl, substituted 2-naphthyl, and phenyl groups with the structure: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are each independently, hydrogen, a C.sub.1 -C.sub.4 lower alkyl, a halogen, an amino group from the group consisting of NH.sub.2, NHR and NRR' where R and R' are each a C.sub.1 -C.sub.4 lower alkyl, a phenyl, or an alkoxy group. The present invention is also directed to processes of preparing methyl aryl sulfones and methyl aryl sulfoxides.

  10. Exploring the Effect of Ligand Structural Isomerism in Langmuir-Blodgett Films of Chiral Luminescent Eu(III) Self-Assemblies.

    PubMed

    Galanti, Agostino; Kotova, Oxana; Blasco, Salvador; Johnson, Chloe J; Peacock, Robert D; Mills, Shaun; Boland, John J; Albrecht, Martin; Gunnlaugsson, Thorfinnur

    2016-07-01

    Here we have investigated the influence of the antenna group position on both the formation of chiral amphiphilic Eu(III) -based self-assemblies in CH3 CN solution and, on the ability to form monolayers on the surface of quartz substrates using the Langmuir-Blodgett technique, by changing from the 1-naphthyl (2(R), 2(S)) to the 2-naphthyl (1(R), 1(S)) position. The evaluation of binding constants of the self- assemblies in CH3 CN solution was achieved using conventional techniques such as UV/Visible and luminescence spectroscopies along with more specific circular dichroism (CD) spectroscopy. The binding constants obtained for EuL, EuL2 and EuL3 species in the case of 2-naphthyl derivatives were comparable to those obtained for 1-naphthyl derivatives. The analysis of the changes in the CD spectra of 1(R) and 1(S) upon addition of Eu(III) not only allowed us to evaluate the values of the binding constants but the resulting recalculated spectra may also be used as fingerprints for assignment of the chiral self-assembly species formed in solution. The obtained monolayers were predominantly formed from EuL3 (≈85 %) with the minor species present in ≈15 % EuL2 . PMID:27258206

  11. Exploring the Effect of Ligand Structural Isomerism in Langmuir-Blodgett Films of Chiral Luminescent Eu(III) Self-Assemblies.

    PubMed

    Galanti, Agostino; Kotova, Oxana; Blasco, Salvador; Johnson, Chloe J; Peacock, Robert D; Mills, Shaun; Boland, John J; Albrecht, Martin; Gunnlaugsson, Thorfinnur

    2016-07-01

    Here we have investigated the influence of the antenna group position on both the formation of chiral amphiphilic Eu(III) -based self-assemblies in CH3 CN solution and, on the ability to form monolayers on the surface of quartz substrates using the Langmuir-Blodgett technique, by changing from the 1-naphthyl (2(R), 2(S)) to the 2-naphthyl (1(R), 1(S)) position. The evaluation of binding constants of the self- assemblies in CH3 CN solution was achieved using conventional techniques such as UV/Visible and luminescence spectroscopies along with more specific circular dichroism (CD) spectroscopy. The binding constants obtained for EuL, EuL2 and EuL3 species in the case of 2-naphthyl derivatives were comparable to those obtained for 1-naphthyl derivatives. The analysis of the changes in the CD spectra of 1(R) and 1(S) upon addition of Eu(III) not only allowed us to evaluate the values of the binding constants but the resulting recalculated spectra may also be used as fingerprints for assignment of the chiral self-assembly species formed in solution. The obtained monolayers were predominantly formed from EuL3 (≈85 %) with the minor species present in ≈15 % EuL2 .

  12. SOME BAFS AND BSAFS FOR PAHS IN LAKE TROUT

    EPA Science Inventory

    Bioaccumulation factors (BAFs) for phenanthrene, fluoranthene, pyrene, benz[a]anthracene and chrysene/triphenylene were calculated using the tissue data of Zabik et al. 1996, Food Chem, 55:231-239, and water...

  13. Use of antioxidant enzymes of clam Ruditapes philippinarum as biomarker to polycyclic aromatic hydrocarbon pollution

    NASA Astrophysics Data System (ADS)

    Zhu, Lin; Tang, Xuexi; Wang, Ying; Sui, Yadong; Xiao, Hui

    2016-03-01

    The typical organic pollutant polycyclic aromatic hydrocarbon (PAH) anthracene was selected as a contaminant to investigate its effects on the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in the clam Ruditapes philippinarum. The results show that SOD, CAT and GSH-Px had diff erent induction and inhibition reactions to anthracene stress, and that three diff erent organs in R. philippinarum (visceral mass, muscle tissue and mantle) had diff erent sensitivities to anthracene stress. This study suggest that SOD activities of the visceral mass, CAT activitities of the mantle and the visceral mass, and GSH-Px activity of the muscle tissue could be used as sensitive indicators of anthracene stress in R. philippinarum.

  14. Pt-Catalyzed Enantioselective Cycloisomerization for the Synthesis of Planar-Chiral Ferrocene Derivatives.

    PubMed

    Shibata, Takanori; Uno, Ninna; Sasaki, Tomoya; Kanyiva, Kyalo Stephen

    2016-08-01

    Enantioselective cycloisomerization of 2-ethynyl-1-ferrocenylbenzene derivatives proceeded by using a chiral cationic platinum catalyst at room temperature. The intramolecular reaction gave planar-chiral naphthalene- and anthracene-fused ferrocene derivatives with high to excellent ee.

  15. A molecular-sized tunnel-porous crystal with a ratchet gear structure and its one-way guest-molecule transportation property

    NASA Astrophysics Data System (ADS)

    Kataoka, Keisuke; Yasumoto, Tetsuaki; Manabe, Yousuke; Sato, Hiroyasu; Yamano, Akihito; Katagiri, Toshimasa

    2013-01-01

    An anisotropic tunnel microporous crystal was prepared. Active transportation of anthracene as a guest molecule in the anisotropic tunnels was observed. The direction of anthracene movement implies that the anisotropic tunnel did not work as a flap-check valve. The direction of the movement was consistent with that caused by a Brownian ratchet.An anisotropic tunnel microporous crystal was prepared. Active transportation of anthracene as a guest molecule in the anisotropic tunnels was observed. The direction of anthracene movement implies that the anisotropic tunnel did not work as a flap-check valve. The direction of the movement was consistent with that caused by a Brownian ratchet. Electronic supplementary information (ESI) available. CCDC reference numbers 837539 and 837540. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c2nr30880k

  16. Biodegradation of polycyclic hydrocarbons by Phanerochaete chrysosporium

    EPA Science Inventory

    The ability of the white rot fungus Phanerochaete chrysosporium to degrade polycyclic aromatic hydrocarbons (PAHs) that are present in anthracene oil (a distillation product obtained from coal tar) was demonstrated. Analysis by capillary gas chromatography and high-performance li...

  17. Downscaling the in vitro test of fungal bioremediation of polycyclic aromatic hydrocarbons: methodological approach.

    PubMed

    Drevinskas, Tomas; Mickienė, Rūta; Maruška, Audrius; Stankevičius, Mantas; Tiso, Nicola; Mikašauskaitė, Jurgita; Ragažinskienė, Ona; Levišauskas, Donatas; Bartkuvienė, Violeta; Snieškienė, Vilija; Stankevičienė, Antanina; Polcaro, Chiara; Galli, Emanuela; Donati, Enrica; Tekorius, Tomas; Kornyšova, Olga; Kaškonienė, Vilma

    2016-02-01

    The miniaturization and optimization of a white rot fungal bioremediation experiment is described in this paper. The optimized procedure allows determination of the degradation kinetics of anthracene. The miniaturized procedure requires only 2.5 ml of culture medium. The experiment is more precise, robust, and better controlled comparing it to classical tests in flasks. Using this technique, different parts, i.e., the culture medium, the fungi, and the cotton seal, can be analyzed. A simple sample preparation speeds up the analytical process. Experiments performed show degradation of anthracene up to approximately 60% by Irpex lacteus and up to approximately 40% by Pleurotus ostreatus in 25 days. Bioremediation of anthracene by the consortium of I. lacteus and P. ostreatus shows the biodegradation of anthracene up to approximately 56% in 23 days. At the end of the experiment, the surface tension of culture medium decreased comparing it to the blank, indicating generation of surfactant compounds. PMID:26660875

  18. Simulated transport of polycyclic aromatic hydrocarbons in artificial streams

    SciTech Connect

    Bartell, S.M.; Landrum, P.F.; Giesy, J.P.; Leversee, G.J.

    1981-01-01

    A model was constructed to predict the pattern of flow and accumulation of three polycyclic aromatic hydrocarbons (PAH) (anthracene, naphthalene, and benzo(a)pyrene) in artificial streams located on the Savannah River Plant near Aiken, South Carolina. Predictions were based upon the premise that the fundamental chemistry of individual PAH contains useful information for predictive purposes. Model processes included volatilization, photolysis, sorption to sediments and particulates, and net accumulation by biota. Simulations of anthracene transport were compared to results of an experiment conducted in the streams. The model realistically predicted the concentration of dissolved anthracene through time and space. Photolytic degradation appeared to be a major pathway of anthracene flux from the streams.

  19. MULTISUBSTRATE BIODEGRADATION KINETICS FOR BINARY AND COMPLEX MIXTURES OF POLYCYCLIC AROMATIC HYDROCARBONS

    EPA Science Inventory

    Biodegradation kinetics were studied for binary and complex mixtures of nine polycyclic aromatic hydrocarbons (PAHs): naphthalene, 1-methylnaphthalene, 2-methylnaphthalene, 2-ethylnaphthalene, phenanthrene, anthracene, pyrene, fluorene and fluoranthene. Discrepancies between the ...

  20. Photon upconversion sensitized by a Ru(II)-pyrenyl chromophore

    PubMed Central

    Deng, Fan; Lazorski, Megan S.; Castellano, Felix N.

    2015-01-01

    The near-visible-to-blue singlet fluorescence of anthracene sensitized by a ruthenium chromophore with a long-lived triplet-excited state, [Ru(5-pyrenyl-1,10-phenanthroline)3](PF6)2, in acetonitrile was investigated. Low intensity non-coherent green light was used to selectively excite the sensitizer in the presence of micromolar concentrations of anthracene generating anti-Stokes, singlet fluorescence in the latter, even with incident power densities below 500 μW cm−2. The resultant data are consistent with photon upconversion proceeding from sensitized triplet–triplet annihilation (TTA) of the anthracene acceptor molecules, confirmed through transient absorption spectroscopy as well as static and dynamic photoluminescence experiments. Additionally, quadratic-to-linear incident power regimes for the upconversion process were identified for this composition under monochromatic 488 nm excitation, consistent with a sensitized TTA mechanism ultimately producing the anti-Stokes emission characteristic of anthracene singlet fluorescence. PMID:25987571