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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. 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

    2016-04-20

    Large-size single crystalline nanosheets of 9,10-bis(phenylethynyl)-anthracene were prepared by a facile solution process and were fully characterized. The prototype photodetector was then fabricated on the basis of a single nanosheet and exhibited superior performance with the largest photoresponse ratio up to ca. 10(5). Moreover, the nanosheets show obvious light emission anisotropy. PMID:26486880

  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. 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.

  7. 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.

  8. Crystal structure of 9,10-bis-(1,3-di-thiol-2-yl-idene)-9,10-di-hydro-anthracene.

    PubMed

    Ren, Yi; Lee, Semin; Bertke, Jeffery A; Moore, Jeffrey S

    2015-12-01

    The crystal structure of the well-studied 9,10-bis-(1,3-di-thiol-2-yl-idene)-9,10-di-hydro-anthracene mol-ecule, C20H12S4, (I), also known as exTTF, is reported. The mol-ecular structure of (I) consists of a di-hydro-anthracene moiety with two 1,3-di-thiol-2-yl-idene substituents. This is a saddle-shaped mol-ecule, which inter-acts with a close neighbor through various π-π and C-H⋯π contacts to form a 'dimer'. These 'dimers' inter-act through a series of C-H⋯S and C-H⋯π contacts to construct a complex three-dimensional extended structure. PMID:26870408

  9. 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

  10. Crystal structure of 9,10-bis­(1,3-di­thiol-2-yl­idene)-9,10-di­hydro­anthracene

    PubMed Central

    Ren, Yi; Lee, Semin; Bertke, Jeffery A.; Moore, Jeffrey S.

    2015-01-01

    The crystal structure of the well-studied 9,10-bis­(1,3-di­thiol-2-yl­idene)-9,10-di­hydro­anthracene mol­ecule, C20H12S4, (I), also known as exTTF, is reported. The mol­ecular structure of (I) consists of a di­hydro­anthracene moiety with two 1,3-di­thiol-2-yl­idene substituents. This is a saddle-shaped mol­ecule, which inter­acts with a close neighbor through various π–π and C—H⋯π contacts to form a ‘dimer’. These ‘dimers’ inter­act through a series of C—H⋯S and C—H⋯π contacts to construct a complex three-dimensional extended structure. PMID:26870408

  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. Electronic properties of anthracene derivatives for blue light emitting electroluminescent layers in organic light emitting diodes: a density functional theory study.

    PubMed

    Raghunath, P; Reddy, M Ananth; Gouri, C; Bhanuprakash, K; Rao, V Jayathirtha

    2006-01-26

    Molecular level parameters are investigated computationally to understand the factors that are responsible for the higher efficiency in derivatives of 9,10-bis(1-naphthyl)anthracene (alpha-ADN), 9,10-bis(2-naphthyl)anthracene (beta-ADN), their tetramethyl derivatives (alpha,beta-TMADN) and the t-Bu derivative (beta-TBADN) as blue light emitting electroluminescent (EL) layers in organic light emitting diodes (OLEDs). DFT studies at the B3LYP/6-31G(d,p) level have been carried out on the substituted anthracenes. The absorption spectra are simulated using time dependent DFT methods (TD-DFT) whereas the emission spectra are approximated by optimizing the excited state by HF/CI-Singles and then carrying out the vertical CI calculations by the TD-DFT method. The reorganization energy for estimating the hole and electron transport is calculated. The transfer integrals between parallely stacked molecules in the bulk state are estimated by calculating the electronic splitting. The substituted anthracenes are compared with unsubstituted anthracene and yet untested 9,10-dianthrylanthracene (TANTH). A larger and slower buildup of the electrons and holes in the EL layer, due to the higher reorganization energy and smaller electronic coupling between the adjacent molecules could lead to an increase in hole-electron recombination in the layer and thus increase the efficiency. PMID:16420020

  13. Synthesis, structure, and excimer formation of vesicular assemblies carrying 1- or 2-naphthyl chromophores

    SciTech Connect

    Sisido, Masahiki; Sato, Yasuhiko; Sasaki, Hiroki; Imanishi, Yukio )

    1990-01-01

    New chromophoric amphiphiles consisting of optically active 1- or 2-naphthylalanines, each carrying two long alkyl chains and an ammonium ion, were synthesized. These amphiphiles were found to form vesicular structures in aqueous dispersion, and those having two octadecyl chains showed a gel-liquid crystalline transition around room temperature. UV and CD spectra showed exciton-type interactions for the 2-naphthyl amphiphiles in a high-energy excited state but no dimers or higher aggregates of the naphthyl groups in the ground state. Fluorescence spectra showed monomer and excimer emissions. The circularly polarized fluorescence spectra showed a positive signal at the excimer emission, indicating a chiral excimer configuration.

  14. (Z)-4-(2-Naphthyl­amino)­pent-3-en-2-one

    PubMed Central

    Harrad, Mohamed Anoir; Boualy, Brahim; Oudahmane, Abdelghani; Avignant, Daniel; Rizzoli, Corrado

    2011-01-01

    The title compound, C15H15NO, which was synthesized under solvent-free conditions by the reaction of acetoacetone and 2-naphthyl­amine, adopts a Z conformation about the C=C bond. The enamine–ketone fragment is approximately planar [maximum deviation = 0.026 (3) Å] and forms a dihedral angle of 39.78 (3)° with the naphthalene ring system. An intra­molecular N—H⋯O hydrogen bond is observed. PMID:21837187

  15. Photoactivatable anthracenes.

    PubMed

    Thapaliya, Ek Raj; Captain, Burjor; Raymo, Françisco M

    2014-05-01

    Fifteen substituted maleimide cycloadducts of anthracene derivatives were synthesized in one or two steps from available precursors in yields ranging from 32 to 63%. They differ in the nature of the group on the maleimide nitrogen atom and of the substituents on the anthracene platform. In all instances, the introduction of a maleimide bridge across positions 9 and 10 of the anthracene skeleton isolates electronically its peripheral phenylene rings and suppresses its characteristic fluorescence. The cycloadducts with a 4-(dimethylamino)phenyl group on the maleimide nitrogen atom undergo retro-cycloaddition upon ultraviolet illumination with quantum yields ranging from 0.001 to 0.01. This structural transformation restores the aromatic character of the central ring of the oligoacene chromophore and activates its emission with fluorescence quantum yields ranging from 0.07 to 0.85. Thus, this particular choice of building blocks for the construction of photoresponsive compounds can translate into viable operating principles for fluorescence activation and, ultimately, lead to the realization of valuable photoactivatable fluorophores for imaging applications. PMID:24716594

  16. 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

  17. 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

  18. 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

  19. 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.

  20. X-ray and DFT calculated structures of 2-(1 H-imidazol-1-yl)-1-(2-naphthyl)ethan-1-one N-phenylthiosemicarbazone and 2-(1 H-imidazol-1-yl)-1-(2-naphthyl)ethan-1-one N-(4-chlorophenyl)thiosemicarbazone

    NASA Astrophysics Data System (ADS)

    Sahin, Z. S.; Septioglu, E.; Calis, U.; Isik, S.

    2014-12-01

    Crystal and molecular structures of two new compounds 2-(1 H-imidazol-1-yl)-1-(2-naphthyl)ethan-1-one N-phenylthiosemicarbazone, C22H19N5S, ( I) and 2-(1 H-imidazol-1-yl)-1-(2-naphthyl)ethan-1-one N-(4-chlorophenyl)thiosemicarbazone, C22H18ClN5S, ( II) have been determined by single-crystal X-ray diffraction. Molecular geometries from X-ray experiment of I and II have been compared with those calculated using the Density Functional Theory (DFT) with B3LYP/6-31G( d, p) basis set. Both compounds crystallize in the monoclinic space group P21/ c with Z = 4: a = 13.2880(5), 14.2648(3) Å, b = 9.4122(2), 9.3892(3) Å, c = 15.6341(6), 15.6268(4) Å, β = 101.779(3)°, 104.926(2)°, for I and II, respectively. An extensive two-dimensional network of N-H⋯N hydrogen bonds and π-ring interactions are responsible for crystal stabilization in both structures.

  1. 40 CFR 721.715 - Trisubstituted anthracene.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Trisubstituted anthracene. 721.715... 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)...

  2. 40 CFR 721.715 - Trisubstituted anthracene.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Trisubstituted anthracene. 721.715... 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)...

  3. 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.

  4. 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

  5. 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.

  6. Semiconducting Polymers Consisting of Anthracene and Benzotriazole Units for Organic Solar Cells.

    PubMed

    Shin, Seung Ah; Kim, Ji-Hoon; Park, Jong Baek; Hwang, Do-Hoon

    2015-02-01

    An alternating copolymer composed of 2,6-dibromo-9,10-bis(2-ethylhexyloxy)anthracene and benzotriazole units, poly(An-alt-BTz), was synthesized, through a Suzuki cross-coupling polymerization, for use in photovoltaic devices as a p-type electron donor. For the reduction of the bandgap energy of benzotriazole units, 5,5'-dibromo-2,2'-bithiophene, or 2,5-dibromothieno [3,2-b] thiophene units were introduced into the polymer. Poly(anthracene-co-benzotriazole-co-bithiophene(thienothiophene))s were synthesized using the same polymerization reactions. The measured optical bandgap energy of poly(anthracene-alt-benzotriazole) was 2.62 eV. As the contents of the flat comonomer units in the ter-polymers increased, the bandgap energies of the resulting polymers decreased up to 1.95 eV. The energy levels of the HOMO and the LUMO of the copolymers were determined from the cyclic voltammetry. Photovoltaic devices were fabricated with the polymers as electron donors and PC71 BM as an electron acceptor. One of the fabricated devices showed the maximum PCE of 0.74% with 0.57 V of VOC, 2.59 mA/cm2 of JSC, and 0.48 of FF under AM 1.5G (100 mW/cm2) condition. PMID:26353683

  7. 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

  8. Effect of the addition of a nonaqueous polar solvent (glycerol) on enzymatic catalysis in reverse micelles. Hydrolysis of 2-naphthyl acetate by alpha-chymotrypsin.

    PubMed

    Falcone, R Darío; Biasutti, M Alicia; Correa, N Mariano; Silber, Juana J; Lissi, Eduardo; Abuin, Elsa

    2004-07-01

    The kinetics of hydrolysis of 2-naphthyl acetate (2-NA) catalyzed by alpha-chymotrypsin (alpha-CT), in reverse micellar solutions formed by glycerol (GY)-water (38% v/v) mixture/sodium bis(2-ethylhexyl)sulfosuccinate (AOT)/n-heptane has been determined by spectroscopic measurements. To compare the efficiency of this reaction with that observed in micelles with water in the core, as well as in the corresponding homogeneous media, the reaction was also studied in water/AOT/n-heptane reverse micellar solutions and in both homogeneous media (water and GY-water, 38% v/v mixture). In every media, alpha-CT was characterized by the absorption and emission spectra, the fluorescence lifetimes, and the fluorescence anisotropy of its tryptophan residues. The effect of AOT concentration on the kinetic parameters obtained in the micellar systems was determined, at a constant molar ratio of the inner polar solvent and surfactant. Moreover, the data obtained allowed the evaluation of the 2-NA partition constant between the organic and the micellar pseudophase. It is shown that the addition of GY to the micelle interior results in an increase in the catalytic properties of alpha-CT. The fluorescence anisotropy studies in the different media show that the addition of GY increases the viscosity as compared with the aqueous systems. It seems that the GY addition to the reverse micellar aggregates results in a decrease of the conformational mobility of alpha-CT, which leads to an increase of the enzyme stability and activity. PMID:16459586

  9. 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).

  10. Growth of rhodococcus S1 on anthracene.

    PubMed

    Tongpim, S; Pickard, M A

    1996-03-01

    Three slow-growing bacteria were isolated from a mixed culture enriched for growth on anthracene, using creosote-contaminated soil as the inoculum. Organisms were shown to use anthracene by the production of a clear zone around the colony after a mineral salts agar plate was sprayed with anthracene. All three bacteria were nonmotile, nonsporulating, gram-positive rods and stained acid-fast. Physiological and biochemical tests, GC content, and cell wall lipid patterns of whole cell methanolysates indicated that they belonged to the Nocardia-Mycobacterium-Rhodococcus group. On the basis of these characteristics and pyrolysis gas chromatography, they were assigned to the genus Rhodococcus. Growth of the isolates was slow on crystalline anthracene, giving a doubling time of 1.5-3 days, and they grew mainly on the crystal surface. When anthracene was supplied by precipitation from a solvent, doubling time was reduced to 1 day. All three isolates mineralized anthracene but not phenanthrene or naphthalene, nor could they grow on naphthalene, phenanthrene, fluorene, fluoranthene, acenaphthene, pyrene, chrysene, or naphthacene as sole carbon source. One isolate, Rhodococcus S1, was able to use 2-methylanthracene or 2-chloroanthracene as carbon source but not 1- or 9-substituted analogs. These results suggest that the initial enzyme attacking anthracene in these isolates has a narrow substrate specificity. PMID:8868237

  11. 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

  12. 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

  13. o-Carborane-based anthracene: a variety of emission behaviors.

    PubMed

    Naito, Hirofumi; Morisaki, Yasuhiro; Chujo, Yoshiki

    2015-04-20

    An o-carborane-based anthracene was synthesized, and single crystals, with incorporated solvent molecules, were obtained from the CHCl3 , CH2 Cl2 , and C6 H6 solutions. The anthracene ring in the crystal is highly distorted by the formation of a π-stacked dimer between the anthracene units. The crystals exhibited a variety of emission behaviors such as aggregation-induced emission (AIE), crystallization-induced emission (CIE), aggregation-caused quenching (ACQ), and multichromism. PMID:25729004

  14. 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.

  15. 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. PMID:25135171

  16. 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

  17. 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

  18. 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

  19. 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.

  20. 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.

  1. Small molecule recognition of mephedrone using an anthracene molecular clip.

    PubMed

    Kellett, Kathryn; Broome, J Hugh; Zloh, Mire; Kirton, Stewart B; Fergus, Suzanne; Gerhard, Ute; Stair, Jacqueline L; Wallace, Karl J

    2016-06-14

    An anthracene molecular probe has been synthesised and shown to target mephedrone, a stimulant drug from the cathinone class of new psychoactive substances (NPS). A protocol has been developed to detect mephedrone via the probe using NMR spectroscopy in a simulated street sample containing two of the most common cutting agents, benzocaine and caffeine. PMID:27198990

  2. Comparing anthracene and fluorene degradation in anthracene and fluorene-contaminated soil by single and mixed plant cultivation.

    PubMed

    Somtrakoon, Khanitta; Chouychai, Waraporn; Lee, Hung

    2014-01-01

    The ability of three plant species (sweet corn, cucumber, and winged bean) to remediate soil spiked with 138.9 and 95.9 mg of anthracene and fluorene per kg of dry soil, respectively, by single and double plant co-cultivation was investigated. After 15 and 30 days of transplantation, plant elongation, plant weight, chlorophyll content, and the content of each PAH in soil and plant tissues were determined. Based on PAH removal and plant health, winged bean was the most effective plant for phytoremediation when grown alone; percentage of fluorene and anthracene remaining in the rhizospheric soil after 30 days were 7.8% and 24.2%, respectively. The most effective combination of plants for phytoremediation was corn and winged bean; on day 30, amounts of fluorene and anthracene remaining in the winged bean rhizospheric soil were 3.4% and 14.3%, respectively; amounts of fluorene and anthracene remaining in the sweet corn rhizospheric soil were 4.1% and 8.8%, respectively. Co-cultivation of sweet corn and cucumber could remove fluorene to a higher extent than anthracene from soil within 15 days, but these plants did not survive and died before day 30. The amounts of fluorene remaining in the rhizospheric soil of corn and cucumber were only 14% and 17.3%, respectively, on day 15. No PAHs were detected in plant tissues. This suggests that phytostimulation of microbial degradation in the rhizosphere was most likely the mechanism by which the PAHs were removed from the spiked soil. The results show that co-cultivation of plants has merit in the phytoremediation of PAH-spiked soil. PMID:24912240

  3. Surfactant assisted self-assembly of zinc 5,10-bis (4-pyridyl)-15,20-bis (4-octadecyloxyphenyl) porphyrin into supramolecular nanoarchitectures.

    PubMed

    Gautam, Renu; Chauhan, S M S

    2014-10-01

    The surfactant assisted self-assembly (SAS) method has been used in the formation of nanocubes, nanorods and microrods from zinc 5,10-bis (4-pyridyl)-15,20-bis (4-octadecyloxyphenyl) porphyrin. By the dropwise addition of chloroform solution of the zinc porphyrin into an aqueous solution of cetyltrimethylammonium bromide (CTAB), cuboidal nanostructures are formed at the initial stage. The nanocubes are transformed into nanorods and microrods by aging under ambient conditions. The longer nanorods with well defined edges have been formed with lower concentration of porphyrin solution whereas the shorter nanorods have been formed with higher concentration of zinc porphyrin. The synergistic effect of hydrophobic interactions by the long alkyl chains substituted on the peripheral phenyl rings of porphyrin and axial coordination of pyridyl nitrogen atoms with central zinc is mainly responsible for the formation of different nanostructures. The nanostructures were characterized by UV-visible spectra, fluorescence spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), IR spectroscopy and X-ray diffraction (XRD) pattern. PMID:25175235

  4. Photoinduced Charge and Energy Transfer within meta- and para-Linked Chlorophyll a-Perylene-3,4:9,10-bis(dicarboximide) Donor-Acceptor Dyads.

    PubMed

    Huang, Guan-Jhih; Harris, Michelle A; Krzyaniak, Matthew D; Margulies, Eric A; Dyar, Scott M; Lindquist, Rebecca J; Wu, Yilei; Roznyatovskiy, Vladimir V; Wu, Yi-Lin; Young, Ryan M; Wasielewski, Michael R

    2016-02-01

    Connecting electron donors and acceptors to a benzene ring in a meta or para relationship results in quantum interference effects that can strongly influence charge separation (CS) and charge recombination (CR) processes in these systems. We report on the energy and electron transfer behavior of chlorophyll-based para- and meta-linked donor-bridge-acceptor (D-B-A) dyads, where the semisynthetic chlorophyll a derivative, zinc methyl 3-ethyl-pyrochlorophyllide a (D), is covalently attached at its 20-position to the para position of one phenyl of diphenylacetylene (B). The meta or para position of the phenyl in B distal to the donor is in turn attached to perylene-3,4:9,10-bis(dicarboximide) (PDI) (A). Photoexcitation of the D-B-A dyads produces long-lived radical ion pairs D(•+)-B-A(•-), which recombine to the ground state and to both (3*)D-B-A and D-B-(3*)A. Time-resolved optical and electron paramagnetic resonance spectroscopies were used to monitor the charge transfer and triplet energy transfer (TEnT) processes. At longer times, TEnT occurs from (3*)D-B-A to D-B-(3*)A. Surprisingly, the D-B-A molecules linked via the meta linkage exhibit faster CS, CR, and TEnT rates than do those with the para linkage in contrast to most other meta/para-linked D-B-A molecules previously examined. PMID:26731377

  5. Enhanced photostability of an anthracene-based dye due to supramolecular encapsulation: a new type of photostable fluorophore for single-molecule study.

    PubMed

    Mitsui, Masaaki; Higashi, Koji; Takahashi, Ryoya; Hirumi, Yohei; Kobayashi, Kenji

    2014-08-01

    For single-molecule fluorescence studies, highly photostable fluorophores are absolutely imperative, because photo-induced degradation (i.e., photobleaching) limits the observation time of individual molecules. Herein, the photophysics and photostability of a highly fluorescent 9,10-bis(phenylethynyl)anthracene derivative (G) and its self-assembled boronic ester encapsulation complex (G@Cap) embedded in a glassy polymer matrix are investigated by single-molecule fluorescence spectroscopy (SMFS). The heterogeneity of the fluorescence emission wavelength and triplet blinking kinetics of the guest G are significantly decreased by supramolecular encapsulation due to conformational restriction and reduced heterogeneity in the local environment. A nearly 10-fold increase in the photostability of G due to encapsulation is quantitatively confirmed by evaluating the photobleaching yields of G and G@Cap. In addition, it is found that the G@Cap is >30-fold more photostable than rhodamine 6G, a widely used fluorescent dye in single-molecule studies. These results demonstrate that the G@Cap can serve as a very bright, long-lasting fluorescent probe for single-molecule studies. PMID:24887756

  6. The effects of anthracene and methylated anthracenes on gap junctional intercellular communication in rat liver epithelial cells.

    PubMed

    Upham, B L; Weis, L M; Rummel, A M; Masten, S J; Trosko, J E

    1996-12-01

    Polycyclic aromatic hydrocarbons (PAHs), many of which are known carcinogens, are derived from the pyrolysis of organic materials. A rich source of PAHs is cigarette smoke, which contains methylated anthracenes and phenanthrenes as the predominant PAHs. The tumor-promoting activity of cigarette smoke has been well documented. The down-regulation of gap junction intercellular communication (GJIC) by nongenotoxic chemicals and several oncogenes has been implicated in tumor promotion. Therefore, we determined the effects of the three isomers of methylanthracene on GJIC in WB-F344 rat liver epithelial cells. Anthracene and 2-methylanthracene did not significantly inhibit GJIC, whereas anthracene methylated in the 1 or 9 position reversibly inhibited GJIC with I50 values of 22 and 36 microM, respectively. Inhibition occurred within 15 min. In conclusion, the biological effect of methylanthracene depends on the ring position of the methyl group, and these inhibitory isomers could play a potential role in tumor promotion of methylated PAH-rich mixtures such as cigarette smoke and crude oil products. PMID:8954755

  7. 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.

  8. 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).

  9. Flow cytometric determination of the photoinduced toxicity of anthracene to the green alga selenastrum capricornutum

    SciTech Connect

    Gala, W.R.; Giesy, J.P. . Dept. of Fisheries and Wildlife)

    1994-05-01

    Certain PAHs are photosensitizers and in the presence of solar radiation can cause toxicity to aquatic plants and animals. The photoinduced toxicity of anthracene to the green alga Selenastrum capricornutum was assessed by the use of flow cytometry to measure cell size, cellular chlorophyll concentration, and cell viability. Anthracene was slightly toxic in the absence of UV-A radiation. The detection of the direct toxicity of anthracene in this study at a concentration of 19 [mu]g/L anthracene resulted from the use of sensitive flow cytometric measures. There was a significant interaction between anthracene and UV-A radiation, which, in combination, caused significant toxic effects on Selenastrum capricornutum. The most sensitive flow cytometric measure of toxicity was the stress index (SI), which was predictive of longer term effects on cell growth. The 28-h EC50 and EC10 and for the SI for Selenastrum capricornutum were 16.1 and 8.3 [mu]g/L anthracene, respectively, at 125 [mu]W/cm[sup 2] UV-A. All combinations for anthracene and UV-A that inhibited algal growth also caused a significantly greater number of nonviable cells. The flow cytometric methods used in this study proved to be sensitive, predictive measures of the direct and photo-induced toxicity of anthracene and UV-A radiation to Selenastrum capricornutum.

  10. Electron transmission through a class of anthracene aldehyde molecules

    NASA Astrophysics Data System (ADS)

    Petreska, Irina; Ohanesjan, Vladimir; Pejov, Ljupco; Kocarev, Ljupco

    2016-03-01

    Transmission of electrons via metal-molecule-metal junctions, involving rotor-stator anthracene aldehyde molecules is investigated. Two model barriers having input parameters evaluated from accurate ab initio calculations are proposed and the transmission coefficients are obtained by using the quasiclassical approximation. Transmission coefficients further enter in the integral for the net current, utilizing Simmons' method. Conformational dependence of the tunneling processes is evident and the presence of the side groups enhances the functionality of the future single-molecule based electronic devices.

  11. 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.

  12. Macrocrystals of Colloidal Quantum Dots in Anthracene: Exciton Transfer and Polarized Emission

    NASA Astrophysics Data System (ADS)

    Soran-Erdem, Zeliha; Erdem, Talha; Hernandez-Martinez, Pedro Ludwig; Akgul, Mehmet Zafer; Gaponik, Nikolai; Demir, Hilmi Volkan

    We systematically investigate the exciton energy transfer from anthracene host (donor) to quantum dots (acceptor) in a centimeter-scale macrocrystal of nonpolar colloidal quantum dots incorporated into anthracene. The decrease in photoluminescence lifetime of the donor anthracene indicate a strong energy transfer with increasing quantum dot concentration in the macrocrystals. In addition, anisotropic emission from the isotropic quantum dots in anthracene macrocrystals was observed. The quantum dots inside the anthracene host acquired a polarization ratio of ~1.5 at 0 degree collection angle, and this increases to ~2.5 at the collection angle of 60 degree. Finally, a proof-of-concept application of these excitonic macrocrystals as tunable color converters was employed in light-emitting diodes. Bilkent University.

  13. 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.

  14. Synthesis of anthracene derivatives of 1,3-diazabicyclo[3.1.0]hex-3-ene

    NASA Astrophysics Data System (ADS)

    Mahmoodi, Nosrat O.; Mirkhaef, Safoura; Ghavidast, Atefeh

    2015-02-01

    Novel mono- and bis-photochromic compounds of 1,3-diazabicyclo[3.1.0]hex-3-enes based on anthracene moiety were synthesized efficiently. Photochromic compounds were synthesized through the reaction of 10-(hydroxymethyl)anthracene-9-carbaldehyde and anthracene-9-carbaldehyde or 9,10-anthracenedicarbaldehyde as bis-aldehydes with ketoaziridines in dry DMF at room temperature. Photochromic compounds exhibited photochromic behavior both in solution and in solid state by irradiation under UV light at 254 nm. Compounds bearing 4-NO2 on aziridine moiety showed intensive color change. Compounds were characterized by IR, 1H NMR, 13C NMR, and UV-Vis.

  15. 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.

  16. A procedure for the joint evaluation of substrate partitioning and kinetic parameters for reactions catalyzed by enzymes in reverse micellar solutions. I. Hydrolysis of 2-naphthyl acetate catalyzed by lipase in sodium 1,4-bis(2-ethylhexyl) sulphosuccinate (AOT)/buffer/heptane.

    PubMed

    Aguilar, L F; Abuin, E; Lissi, E

    2001-04-15

    A simple method useful for the joint evaluation of substrate partitioning and kinetic parameters for reactions catalyzed by enzymes entrapped in reverse micelles is proposed. The method is applied to the hydrolysis of 2-naphthyl acetate (2-NA) catalyzed by lipase in sodium 1,4-bis(2-ethylhexyl) sulfosuccinate (AOT)/buffer/heptane reverse micellar solutions. In the presence of micelles, the relationship between the initial reaction rate and the analytical concentration of 2-NA was dependent on AOT concentration at a constant W ([water]/[AOT]) value. The dependence of the initial reaction rate profiles with [AOT] was analyzed according with the method proposed to obtain the partition constant of 2-NA between the micelles and the external solvent, Kp. A value of Kp = 2.7 L mol(-1) was obtained irrespective of the water content of the micelles (W from 5 to 20). The catalytic rate constant kcat in the micellar solutions was independent of [AOT] but slightly decreased with an increase in W from 2 x 10(-6) mol g(-1) s(-1) at W = 5 to 1.2 x 10(-6) mol g(-1) s(-1) at W = 20. The apparent Michaelis constant determined in terms of the analytical concentration of 2-NA increased with [AOT] at a given W and moderately decreased with W at a fixed [AOT]. The increase with [AOT] is accounted for by considering the partitioning of the substrate. After correction for the partitioning of 2-NA values of (Km)corr were obtained as 3.9 x 10(-3) mol L(-1) (W = 5), 4.6 x 10(-3) mol L(-1) (W = 10), 2.3 x 10(-3) mol L(-1) (W = 15), and 1.7 x 10(-3) mol L(-1) (W = 20). The rate parameters in the aqueous phase in the absence of micelles, were obtained as (kcat)aq = 7.9 x 10(-6) mol g(-1) s(-1) and (Km)aq = 2.5 x 10(-3) mol L(-1). In order to compare the efficiency of the enzyme in the micellar solution with that in aqueous phase, the values of (Km)corr were in turn corrected to take into account differences in the substrate activity, obtaining so a set of (Km)*corr values. The efficiency of the

  17. 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

  18. 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.

  19. 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.

  20. 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

  1. Fast radiative cooling of anthracene: Dependence on internal energy

    NASA Astrophysics Data System (ADS)

    Martin, S.; Ji, M.; Bernard, J.; Brédy, R.; Concina, B.; Allouche, A. R.; Joblin, C.; Ortega, C.; Montagne, G.; Cassimi, A.; Ngono-Ravache, Y.; Chen, L.

    2015-11-01

    Fast radiative cooling of anthracene cations (C14H10 ) + is studied with a compact electrostatic storage device, the Mini-Ring. The time evolution of the internal energy distribution of the stored ions is probed in a time range from 3 to 7 ms using laser-induced dissociation with 3.49-eV photons. The population decay rate due to radiative emission is measured to vary from 25 to 450 s-1 as a function of the excitation energy in the range from 6 to 7.4 eV. After corrections of the infrared emission effect via vibrational transitions, the fluorescence emission rate due to electronic transitions from thermally excited electronic states is estimated and compared with a statistical molecular approach. In the considered internal energy range, the radiative cooling process is found to be dominated by the electronic transition, in good agreement with our previous work [S. Martin et al., Phys. Rev. Lett. 110, 063003 (2013), 10.1103/PhysRevLett.110.063003] focused on a narrower energy range.

  2. Competition between singlet fission and charge separation in solution-processed blend films of 6,13-bis(triisopropylsilylethynyl)pentacene with sterically-encumbered perylene-3,4:9,10-bis(dicarboximide)s.

    PubMed

    Ramanan, Charusheela; Smeigh, Amanda L; Anthony, John E; Marks, Tobin J; Wasielewski, Michael R

    2012-01-11

    The photophysics and morphology of thin films of N,N-bis(2,6-diisopropylphenyl)perylene-3,4:9,10-bis(dicarboximide) (1) and the 1,7-diphenyl (2) and 1,7-bis(3,5-di-tert-butylphenyl) (3) derivatives blended with 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-Pn) were studied for their potential use as photoactive layers in organic photovoltaic (OPV) devices. Increasing the steric bulk of the 1,7-substituents of the perylene-3,4:9,10-bis(dicarboximide) (PDI) impedes aggregation in the solid state. Film characterization data using both atomic force microscopy and X-ray diffraction showed that decreasing the PDI aggregation by increasing the steric bulk in the order 1 < 2 < 3 correlates with a decrease in the density/size of crystalline TIPS-Pn domains. Transient absorption spectroscopy was performed on ~100 nm solution-processed TIPS-Pn:PDI blend films to characterize the charge separation dynamics. These results showed that selective excitation of the TIPS-Pn results in competition between ultrafast singlet fission ((1*)TIPS-Pn + TIPS-Pn → 2 (3*)TIPS-Pn) and charge transfer from (1*)TIPS-Pn to PDIs 1-3. As the blend films become more homogeneous across the series TIPS-Pn:PDI 1 → 2 → 3, charge separation becomes competitive with singlet fission. Ultrafast charge separation forms the geminate radical ion pair state (1)(TIPS-Pn(+•)-PDI(-•)) that undergoes radical pair intersystem crossing to form (3)(TIPS-Pn(+•)-PDI(-•)), which then undergoes charge recombination to yield either (3*)PDI or (3*)TIPS-Pn. Energy transfer from (3*)PDI to TIPS-Pn also yields (3*)TIPS-Pn. These results show that multiple pathways produce the (3*)TIPS-Pn state, so that OPV design strategies based on this system must utilize this triplet state for charge separation. PMID:22111926

  3. 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.

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

    PubMed

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

    2011-09-01

    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

  5. 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

  6. (E)-Methyl 3-(10-bromo­anthracen-9-yl)acrylate

    PubMed Central

    Bugenhagen, Bernhard; Al Jasem, Yosef; Hindawi, Bassam al; Al Rawashdeh, Nathir; Thiemann, Thies

    2013-01-01

    In the title mol­ecule, C18H13BrO2, the anthracene unit forms an angle of 46.91 (2)° with the mean plane of the methyl acrylate moiety. In the crystal, the mol­ecules arrange themselves into strands parallel to [010] and, due to the crystal symmetry, there are eight strands crossing the unit cell. In each strand, mol­ecules form short C—H⋯O and C—H⋯π contacts and have their anthracene groups parallel to each other. Neighboring strands, related by a c-glide operation, are connected via C—H⋯O inter­actions and form a layer parallel to (100). The arrangement of the acrylate and anthracene groups in the crystal do not allow for [2 + 2] or [4 + 4] cyclo­addition. PMID:24046689

  7. 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

  8. Persistence of benz(a)anthracene degradation products in an enclosed marine ecosystem

    SciTech Connect

    Hinga, K.R.; Pilson, M.E.Q.

    1987-07-01

    Carbon-14-labeled benz(a)anthracene was introduced into an enclosed marine ecosystem that had planktonic primary production and a heterotrophic benthos. Benz(a)anthracene, labeled CO/sub 2/, and operationally defined fractions of labeled degradation products were followed in water and sediments for 202 days. The major fraction of intermediate degradation products was sufficiently water soluble so as not to be readily extractable with organic solvents and at the end was still slowly decaying to CO/sub 2/. Both the parent benz(a)anthracene and degradation products found in the sediment appear to become protected from further alteration after about 2 months and may persist indefinitely. 41 references, 4 figures.

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. Identification and quantification of ozonation products of anthracene and phenanthrene adsorbed on silica particles

    NASA Astrophysics Data System (ADS)

    Perraudin, Emilie; Budzinski, Hélène; Villenave, Eric

    Primary products of the reactions of gas-phase ozone with anthracene and phenanthrene adsorbed on silica model particles have been investigated. Silica was selected as proxy for mineral atmospheric particles. The particles, coated with anthracene or phenanthrene and placed on a filter, were exposed in a reaction cell to a gaseous ozone flow. Ozone concentration was constant ((6.0±0.6)×10 13 molecule cm -3) during the experiments. Anthracene, phenanthrene and their ozonation products were then extracted by focused microwave-assisted extraction or fluid pressurized extraction and analyzed by gas chromatography coupled to mass spectrometry. Anthraquinone and anthrone on the one hand, and 1,1'-biphenyl-2,2'-dicarboxaldehyde on the other hand were identified as the products of anthracene and phenanthrene, respectively and quantified versus time of ozone exposure. This kinetical approach allowed to show that anthraquinone, anthrone and 1,1'-biphenyl-2,2'-dicarboxaldehyde are the primary products of the studied reactions, and to determine their formation yields (respectively, 0.42±0.04, 0.056±0.005 and 1.0±0.4).

  14. 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.

  15. Coherent electronic energy transfer and nonlinear polariton effects in anthracene-doped naphthalene crystals

    SciTech Connect

    Connolly, M.A.

    1987-01-01

    The nature of electronic energy transfer in strain-free mounted anthracene-doped naphthalene single crystals at frequencies near that of the (0.0) a-exciton in naphthalene was probed using sensitized resonant two-photon fluorescence excitation (TPE) and second harmonic generation (SHG) spectroscopies. The naphthalene-to-anthracene TPE intensity ratios were found to be 1.2 and 1.6, for excitation of the zero-phonon transition at 1.6 K and 20 K, respectively. This result is consistent with coherent exciton-polariton electronic energy transfer at liquid helium temperatures, and incoherent transfer at high temperatures. Energy transfer for the pure and the anthracene-doped naphthalene systems under investigation was determined to be in the capture limited regime. The polariton trapping event is discussed in terms of scattering off a trap with subsequent trapping (i.e., capture) and scattering off a trap without subsequent trapping (i.e., trap scattering). Thermal broadening and temperature dependences of the TPE and SHG signal intensities for both naphthalene and anthracene are presented and are discussed in terms of the polariton fusion model. The experimental data do not agree with the theoretical predictions; this discrepancy is discussed in terms of the anomalous crystal habit (diamond plates) observed in the present investigation. The first report of a longitudinal exciton in a doped organic molecular system also is reported.

  16. Synthesis of Stair-Stepped Polymers Containing Dibenz[a,h]anthracene Subunits

    SciTech Connect

    Chan, Julian M. W.; Kooi, Steven E.; Swager, Timothy M.

    2010-03-23

    Polycyclic aromatic monomers based on substituted dibenz[a,h]anthracene frameworks have been prepared in high yields. From these, several fluorescent stair-stepped conjugated polymers containing fused aromatic subunits have been synthesized via Sonogashira polycondensations and Glaser-type oxidative couplings. The new polymers were characterized by NMR spectroscopy, gel-permeation chromatography (GPC), UV-vis, and fluorescence spectroscopy.

  17. 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.

  18. Thermal-delayed fluorescence of pyromellitic dianhydride—anthracene trap in charge-transfer pyromellitic dianhyride—phenanthrene host crystal

    NASA Astrophysics Data System (ADS)

    Kozankiewicz, B.

    1990-10-01

    The fluorescence, phosphorescence and delayed fluorescence in an anthracene-doped pyromellitic dianhydride—phenanthrene crystal is studied within the temperature range 200-330 K. The dominating long-lived emission for temperatures above 250 K is thermal-delayed fluorescence, originating from the singlet trap created by thermal promotion of the triplet trap. The trap is formed on the pyromellitic dianhydride—anthracene complex unit. The activation energy of thermal promotions is ≈ 2500 cm -1.

  19. 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.

  20. 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.

  1. 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

  2. Expression of lip genes during growth in soil and oxidation of anthracene by Phanerochaete chrysosporium.

    PubMed Central

    Bogan, B W; Schoenike, B; Lamar, R T; Cullen, D

    1996-01-01

    mRNA extraction from soil and quantitation by competitive reverse transcription-PCR were combined to study the expression of the 10 known lignin peroxidase (lip) genes in anthracene-transforming soil cultures of Phanerochaete chrysosporium. Levels of extractable lipA transcript and protein (LiP H8) were well correlated, although they were separated by a 2-day lag period. The patterns of transcript abundance over time in soil-grown P. chrysosporium varied among the nine lip mRNAs detected; comparison with lip gene expression under different liquid culture conditions suggested an early phase of carbon limitation for the cultures as a whole, which was followed by a transition to nitrogen starvation. Anthracene transformation occurred throughout the 25-day course of the experiment and, therefore, likely involves mechanisms distinct from those involved in oxidation of non-LiP substrate polycyclic aromatic hydrocarbons. PMID:8837425

  3. Monitoring cellular uptake and cytotoxicity of copper(II) complex using a fluorescent anthracene thiosemicarbazone ligand.

    PubMed

    Kate, Anup N; Kumbhar, Anupa A; Khan, Ayesha A; Joshi, Pranaya V; Puranik, Vedavati G

    2014-01-15

    The thiosemicarbazone derivative of anthracene (ATSC, anthracene thiosemicarbazone 1) and its copper(II) complex (CuATSC, 2) were synthesized and characterized by spectroscopic, electrochemical, and crystallographic techniques. Interaction of 1 and 2 with calf thymus (CT) DNA was explored using absorption and emission spectral methods, and viscosity measurements reveal a partial-intercalation binding mode. Their protein binding ability was monitored by the quenching of tryptophan emission using bovine serum albumin (BSA) as a model protein. Furthermore, their cellular uptake, in vitro cytotoxicity testing on the HeLa cell line, and flow cytometric analysis were carried out to ascertain the mode of cell death. Cell cycle analysis indicated that 1 and 2 cause cell cycle arrest in sub-G1 phase. PMID:24328322

  4. A molecular dynamics study on slow ion interactions with the polycyclic aromatic hydrocarbon molecule anthracene

    SciTech Connect

    Postma, J.; Hoekstra, R.; Schlathölter, T.; Tielens, A. G. G. M.

    2014-03-01

    Atomic collisions with polycyclic aromatic hydrocarbon (PAH) molecules are astrophysically particularly relevant for collision energies of less than 1 keV. In this regime, the interaction dynamics are dominated by elastic interactions. We have employed a molecular dynamics simulation based on analytical interaction potentials to model the interaction of low energy hydrogen and helium projectiles with isolated anthracene (C{sub 14}H{sub 10}) molecules. This approach allows for a very detailed investigation of the elastic interaction dynamics on an event by event basis. From the simulation data the threshold projectile kinetic energies above which direct C atom knock out sets in were determined. Anthracene differential energy transfer cross sections and total (dissociation) cross sections were computed for a wide range of projectile kinetic energies. The obtained results are interpreted in the context of PAH destruction in astrophysical environments.

  5. 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

  6. Picosecond spectroscopy of charge-transfer processes. Photochemistry of anthracene-tetranitromethane EDA complexes

    NASA Astrophysics Data System (ADS)

    Masnovi, J. M.; Huffman, J. C.; Kochi, J. K.; Hilinski, E. F.; Rentzepis, P. M.

    1984-04-01

    The temporal sequence of events that follow 532 nm excitation of electron donor-acceptor, EDA, complexes of several substituted anthracenes with tetranitromethane is monitored by means of picosecond spectroscopy. Excitation of the charge-transfer band of these EDA complexes produces high yields of 1 : 1 adducts. Absorption spectra and kinetics of the transient species involved in these photochemical reactions provide the basis for elucidation of the reaction mechanism following charge-transfer excitation to the ion pairs.

  7. (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.

  8. 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

  9. 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.

  10. 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.

  11. Degradation and Mineralization of the Polycyclic Aromatic Hydrocarbons Anthracene and Naphthalene in Intertidal Marine Sediments †

    PubMed Central

    Bauer, James E.; Capone, Douglas G.

    1985-01-01

    The degradation of the polynuclear aromatic hydrocarbons (PAHs) anthracene and naphthalene by the microbiota of intertidal sediments was investigated in laboratory studies. No mineralization of either PAH was observed in the absence of oxygen. Both rates and total amounts of PAH mineralization were strongly controlled by oxygen content and temperature of the incubations. Inorganic nitrogen and glucose amendments had minimal effects on PAH mineralization. The rates and total amounts of PAH mineralized were directly related to compound concentration, pre-exposure time, and concentration. Maximum mineralization was observed at the higher concentrations (5 to 100 μg/g [ppm]) of both PAHs. Optimal acclimation to anthracene and naphthalene (through pre-exposures to the compounds) occurred at the highest acclimation concentration (1,000 ppm). However, acclimation to a single concentration (100 ppm) resulted in initial relative mineralization rates over a range of re-exposure concentrations (1 to 1,000 ppm) being nearly identical. Maximum mineralization of both PAHs occurred after intermediate periods (1 to 2 weeks) of pre-exposure. The fraction of the total heterotrophic population capable of utilizing anthracene or naphthalene as sole carbon source was also greatest after 2 weeks. PMID:16346843

  12. Facile synthesis of dibenzo-7λ3-phosphanorbornadiene derivatives using magnesium anthracene.

    PubMed

    Velian, Alexandra; Cummins, Christopher C

    2012-08-29

    Unprotected dibenzo-7λ(3)-phosphanorbornadiene derivatives RPA (A = C(14)H(10) or anthracene; R = (t)Bu, dbabh = NA, HMDS = (Me(3)Si)(2)N, (i)Pr(2)N) are synthesized by treatment of the corresponding phosphorus dichloride RPCl(2) with MgA·3THF, in cold THF (~20% to 30% isolated yields). Anthracene and the corresponding cyclic phosphane (RP)(n) form as coproducts. Characteristic NMR features of the RPA derivatives include a doublet near 4 ppm in their (1)H NMR spectra and a triplet peak in the 175-212 ppm region of the (31)P NMR spectrum ((2)J(PH) ~14 Hz). The X-ray structures of the AN-PA and (HMDS)PA derivatives are discussed. Thermolysis of RPA benzene-d(6) solutions leads to anthracene extrusion. This process has a unimolecular kinetic profile for the (i)Pr(2)NPA derivative. The 7-phosphanorbornene anti-(i)Pr(2)NP(C(6)H(8)) could be synthesized (70% isolated yield) by thermolysis of (i)Pr(2)NPA in 1,3-cyclohexadiene. PMID:22894133

  13. 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.

  14. Coherent electronic energy transfer and nonlinear polariton effects in anthracene-doped naphthalene crystals

    SciTech Connect

    Connolly, M.A.

    1987-06-01

    The electronic energy transfer in strain-free mounted anthracene-doped naphthalene single crystals at frequencies near that of the (0,0) a-exciton in naphthalene was probed using sensitized resonant two-photon fluorescence excitation (TPE) and second harmonic generation (SHG) spectroscopies. The naphthalene-to-anthracene TPE intensity ratios were 1.2 and 1.6, for excitation of the zero-phonon transition at 1.6 and 20/sup 0/K, respectively. Energy transfer for the pure and the anthracene-doped naphthalene systems was in the capture limited regime, that is, the trapping event occurs on a timescale long compared to the migration of the excitation to the trap. The polariton trapping event is discussed in terms of scattering off a trap with subsequent trapping (i.e., capture) and scattering off a trap without subsequent trapping (i.e., trap scattering). The branching ratio for the trap scattering frequency to the capture frequency, was calculated to be 5 to 1 for the doped system. The branching ratio was used to determine the individual scattering frequencies. The lower bound for the coherent trapping or trap scattering radius was 100 A. Thermal broadening and temperature dependences of TPE and SHG signal intensities are discussed in terms of the polariton fusion model. The first report of a longitudinal exciton in a doped organic molecular system also is reported.

  15. Benz[a]anthracene Biotransformation and Production of Ring Fission Products by Sphingobium sp. Strain KK22

    PubMed Central

    Kunihiro, Marie; Ozeki, Yasuhiro; Nogi, Yuichi; Hamamura, Natsuko

    2013-01-01

    A soil bacterium, designated strain KK22, was isolated from a phenanthrene enrichment culture of a bacterial consortium that grew on diesel fuel, and it was found to biotransform the persistent environmental pollutant and high-molecular-weight polycyclic aromatic hydrocarbon (PAH) benz[a]anthracene. Nearly complete sequencing of the 16S rRNA gene of strain KK22 and phylogenetic analysis revealed that this organism is a new member of the genus Sphingobium. An 8-day time course study that consisted of whole-culture extractions followed by high-performance liquid chromatography (HPLC) analyses with fluorescence detection showed that 80 to 90% biodegradation of 2.5 mg liter−1 benz[a]anthracene had occurred. Biodegradation assays where benz[a]anthracene was supplied in crystalline form (100 mg liter−1) confirmed biodegradation and showed that strain KK22 cells precultured on glucose were equally capable of benz[a]anthracene biotransformation when precultured on glucose plus phenanthrene. Analyses of organic extracts from benz[a]anthracene biodegradation by liquid chromatography negative electrospray ionization tandem mass spectrometry [LC/ESI(−)-MS/MS] revealed 10 products, including two o-hydroxypolyaromatic acids and two hydroxy-naphthoic acids. 1-Hydroxy-2- and 2-hydroxy-3-naphthoic acids were unambiguously identified, and this indicated that oxidation of the benz[a]anthracene molecule occurred via both the linear kata and angular kata ends of the molecule. Other two- and single-aromatic-ring metabolites were also documented, including 3-(2-carboxyvinyl)naphthalene-2-carboxylic acid and salicylic acid, and the proposed pathways for benz[a]anthracene biotransformation by a bacterium were extended. PMID:23686261

  16. Regio- and Stereoselective Metabolism of 7,12-Dimethylbenz[a]anthracene by Mycobacterium vanbaalenii PYR-1

    PubMed Central

    Moody, Joanna D.; Fu, Peter P.; Freeman, James P.; Cerniglia, Carl E.

    2003-01-01

    The degradation of 7,12-dimethylbenz[a]anthracene (DMBA), a carcinogenic polycyclic aromatic hydrocarbon, by cultures of Mycobacterium vanbaalenii PYR-1 was studied. When M. vanbaalenii PYR-1 was grown in the presence of DMBA for 136 h, high-pressure liquid chromatography (HPLC) analysis showed the presence of four ethyl acetate-extractable compounds and unutilized substrate. Characterization of the metabolites by mass and nuclear magnetic resonance spectrometry indicated initial attack at the C-5 and C-6 positions and on the methyl group attached to C-7 of DMBA. The metabolites were identified as cis-5,6-dihydro-5,6-dihydroxy-7,12-dimethylbenz[a]anthracene (DMBA cis-5,6-dihydrodiol), trans-5,6-dihydro-5,6-dihydroxy-7,12-dimethylbenz[a]anthracene (DMBA trans-5,6-dihydrodiol), and 7-hydroxymethyl-12-methylbenz[a]anthracene, suggesting dioxygenation and monooxygenation reactions. Chiral stationary-phase HPLC analysis of the dihydrodiols showed that DMBA cis-5,6-dihydrodiol had 95% 5S,6R and 5% 5R,6S absolute stereochemistry. On the other hand, the DMBA trans-5,6-dihydrodiol was a 100% 5S,6S enantiomer. A minor photooxidation product, 7,12-epidioxy-7,12-dimethylbenz[a]anthracene, was also formed. The results demonstrate that M. vanbaalenii PYR-1 is highly regio- and stereoselective in the degradation of DMBA. PMID:12839762

  17. 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.

  18. Characterization of Multiple-Substrate Utilization by Anthracene-Degrading Mycobacterium frederiksbergense LB501T

    PubMed Central

    Wick, Lukas Y.; Pasche, Natacha; Bernasconi, Stefano M.; Pelz, Oliver; Harms, Hauke

    2003-01-01

    Stable carbon isotope analysis of biomass and analyses of phospholipid fatty acids (PLFA), glycolipid fatty acids (GLFA), and mycolic acids were used to characterize mixed-substrate utilization by Mycobacterium frederiksbergense LB501T under various substrate regimens. The distinct 13C contents of anthracene and glucose as representatives of typical hydrophobic pollutants and naturally occurring organic compounds, respectively, were monitored during formation into biomass and used to quantify the relative contributions of the two carbon sources to biomass formation. Moreover, the influence of mixed-substrate utilization on PLFA, GLFA, and mycolic acid profiles and cell surface hydrophobicity was investigated. Results revealed that M. frederiksbergense LB501T degrades anthracene and forms biomass from it even in the presence of more readily available dissolved glucose. The relative ratios of straight-chain saturated PLFA to the corresponding unsaturated PLFA and the total fraction of saturated cyclopropyl-branched PLFA of M. frederiksbergense LB501T depended on the carbon source and the various rates of addition of mixed substrates, whereas no such trend was observed with GLFA. Higher proportions of anthracene in the carbon source mixture led to higher cell surface hydrophobicities and more-hydrophobic mycolic acids, which in turn appeared to be valuable indicators for substrate utilization by M. frederiksbergense LB501T. The capability of polycyclic aromatic hydrocarbon (PAH)-degrading bacteria to utilize readily available substrates besides the poorly available PAHs favors the buildup of PAH-degrading biomass. Feeding of supplementary carbon substrates may therefore promote bioremediation, provided that it sustains the pollutant-degrading population rather than other members of the microbial community. PMID:14532072

  19. 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

  20. 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.

  1. 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. PMID:10755224

  2. 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

  3. 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.

  4. 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.

  5. Langmuir Fiilms of Anthracene Derivatives on Liquid Mercury I: Symmetric Molecules

    SciTech Connect

    Tamam,L.; Kraack, H.; Sloutskin, E.; Ocko, B.; Pershan, P.; Ofer, E.; Deutsch, M.

    2007-01-01

    The structure and phase sequence of liquid-mercury-supported Langmuir films (LFs) of two symmetric acenes, anthracene and anthraquinone, were studied by surface tensiometry and X-ray diffraction. At low coverage, both form a monolayer of surface-parallel, flat-lying, molecules. At high coverage, we find a monolayer of side-lying molecules, where the molecular plane is surface-normal, and the molecular long axis is surface-parallel. None of these phases exhibit long-range in-plane order.

  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. Triple Benzannulation of Naphthalene via a 1,3,6-Naphthotriyne Synthetic Equivalent. Synthesis of Dibenz[a,c]anthracene.

    PubMed

    Mannes, Philip Z; Onyango, Evans O; Gribble, Gordon W

    2015-11-01

    A new synthesis of dibenzo[a,c]anthracene (4) is described that features the generation, from tetrabromo-bis-triflate 1 and phenyllithium, of a 1,3,6-naphthotriyne (2) synthetic equivalent that is trapped with 3 equiv of furan to form Diels-Alder tris-adduct 3. A subsequent two-step deoxygenation of 3 represents the first synthesis of dibenz[a,c]anthracene (4) that involves a tandem aryne Diels-Alder cycloaddition-deoxygenation strategy. PMID:26452053

  8. Stereoselective metabolism of anthracene and phenanthrene by the fungus Cunninghamella elegans.

    PubMed Central

    Cerniglia, C E; Yang, S K

    1984-01-01

    The fungus Cunninghamella elegans oxidized anthracene and phenanthrene to form predominately trans-dihydrodiols. The metabolites were isolated by reversed-phase high-pressure liquid chromatography for structural and conformational analyses. Comparison of the circular dichroism spectrum of the fungal trans-1,2-dihydroxy-1,2-dihydroanthracene to that formed by rat liver microsomes indicated that the major enantiomer of the trans-1,2-dihydroxy-1,2-dihydroanthracene formed by C. elegans had an S,S absolute stereochemistry, which is opposite to the predominately 1R,2R dihydrodiol formed by rat liver microsomes. C. elegans oxidized phenanthrene primarily in the 1,2-positions to form trans-1,2-dihydroxy-1,2-dihydrophenanthrene. In addition, a minor amount of trans-3,4-dihydroxy-3,4-dihydrophenanthrene was detected. Metabolism at the K-region (9,10-positions) of phenanthrene was not detected. Comparison of the circular dichroism spectra of the phenanthrene trans-1,2- and trans-3,4-dihydrodiols formed by C. elegans to those formed by mammalian enzymes indicated that each of the dihydrodiols formed by C. elegans had an S,S absolute configuration. The results indicate that there are differences in both the regio- and stereoselective metabolism of anthracene and phenanthrene between the fungus C. elegans and rat liver microsomes. PMID:6696409

  9. Diborylated magnesium anthracene as precursor for B2H5(-)-bridged 9,10-dihydroanthracene.

    PubMed

    Pospiech, Steffen; Bolte, Michael; Lerner, Hans-Wolfram; Wagner, Matthias

    2015-05-26

    9,10-(Bpin)2-anthracene (3, HBpin = pinacolborane) was synthesized from 9,10-dibromoanthracene in a stepwise lithiation/borylation sequence. The reaction of 3 with highly activated magnesium furnished the diborylated magnesium anthracene 4, which was quenched in situ with ethereal HCl to yield cis-9,10-(Bpin)2-DHA (cis-5, DHA = 9,10-dihydroanthracene). Compound cis-5, in turn, can be reduced with Li[AlH4] in THF to give its diborate Li2[cis-9,10-(BH3)2-DHA] (Li2 [cis-6]). In the crystal lattice, the THF solvate Li2[cis-6]⋅3 THF establishes a dimeric structure with Li-(μ-H)-B coordination modes. Hydride abstraction from Li2[cis-6] with Me3SiCl yields the B-H-B-bridged DHA Li[7]. This product can also be viewed as a unique cyclic B2H7(-) derivative with a hydrocarbon backbone. Treatment of Li2[cis-6] with the stronger hydride abstracting agent Me3SiOTf (HOTf = trifluoromethanesulfonic acid) in THF affords the THF diadduct of cis-9,10-(BH(OTf))2-DHA. PMID:25892077

  10. Stereoselective metabolism of anthracene and phenanthrene by the fungus Cunninghamella elegans

    SciTech Connect

    Cerniglia, C.E.; Yang, S.K.

    1984-01-01

    The fungus Cunninghamella elegans oxidized anthracene and phenanthrene to form predominately transdihydrodiols. The metabolites were isolated by reversed-phase high-pressure liquid chromatography for structural and conformational analyses. Comparison of the circular dichroism spectrum of the fungal trans-1,2-dihydroxy-1,2-dihydroanthracene to that formed by rat liver microsomes indicated that the major enantiomer of the trans-1,2-dihydroxy-1,2-dihydroanthracene formed by C. elegans had an S,S absolute stereochemistry, which is opposite to the predominately 1R,2R dihydrodiol formed by rat liver microsomes. C. elegans oxidized phenanthrene primarily in the 1,2-positions to form trans-1,2-dihydroxy-1,2-dihydrophenanthrene. In addition, a minor amount of trans-3,4-dihydroxy-3,4-dihydrophenanthrene was detected. Metabolism at the K-region (9,10-positions) of phenanthrene was not detected. Comparison of the circular dichroism spectra of the phenanthrene trans-1,2- and trans-3,4-dihydrodiols formed by C. elegans to those formed by mammalian enzymes indicated that each of the dihydrodiols formed by C. elegans had an S,S absolute configuration. The results indicate that there are differences in both the regio- and stereoselective metabolism of anthracene and phenanthrene between the fungus C. elegans and rat liver microsomes. 26 references.

  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. Direct effects of 9-anthracene compounds on cystic fibrosis transmembrane conductance regulator gating.

    PubMed

    Ai, Tomohiko; Bompadre, Silvia G; Sohma, Yoshiro; Wang, Xiaohui; Li, Min; Hwang, Tzyh-Chang

    2004-10-01

    Anthracene-9-carboxylic acid (9-AC) has been reported to show both potentiation and inhibitory effects on guinea-pig cardiac cAMP-activated chloride channels via two different binding sites, and inhibition of Mg(2+)-sensitive protein phosphatases has been proposed for the mechanism of 9-AC potentiation effect. In this study, we examined the effects of 9-AC on wild-type and mutant human cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels expressed in NIH3T3 or CHO cells. 9-AC inhibits whole-cell CFTR current in a voltage-dependent manner, whereas the potentiation effect is not affected by membrane potentials. Anthracene-9-methanol, an electro-neutral 9-AC analog, fails to block CFTR, but shows a nearly identical potentiation effect, corroborating the idea that two chemically distinct sites are responsible, respectively, for potentiation and inhibitory actions of 9-AC. 9-AC also enhances the activity of deltaR-CFTR, a constitutively active CFTR mutant whose R-domain is removed. In excised inside-out patches, 9-AC increases Po by prolonging the mean burst durations and shortening the interburst durations. We therefore conclude that two different 9-AC binding sites for potentiation and inhibitory effects on CFTR channels are located outside of the R-domain. We also speculate that 9-AC potentiates CFTR activity by directly affecting CFTR gating. PMID:15290302

  13. Direct effects of 9-anthracene compounds on cystic fibrosis transmembrane conductance regulator gating

    PubMed Central

    Ai, T.; Bompadre, S. G.; Sohma, Y.; Wang, X.; Li, M.; Sohma, Y.; Ai, T.

    2005-01-01

    Anthracene-9-carboxylic acid (9-AC) has been reported to show both potentiation and inhibitory effects on guinea-pig cardiac cAMP-activated chloride channels via two different binding sites, and inhibition of Mg2+-sensitive protein phosphatases has been proposed for the mechanism of 9-AC potentiation effect. In this study, we examined the effects of 9-AC on wild-type and mutant human cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels expressed in NIH3T3 or CHO cells. 9-AC inhibits whole-cell CFTR current in a voltage-dependent manner, whereas the potentiation effect is not affected by membrane potentials. Anthracene-9-methanol, an electro-neutral 9-AC analog, fails to block CFTR, but shows a nearly identical potentiation effect, corroborating the idea that two chemically distinct sites are responsible, respectively, for potentiation and inhibitory actions of 9-AC. 9-AC also enhances the activity of ΔR-CFTR, a constitutively active CFTR mutant whose R-domain is removed. In excised inside-out patches, 9-AC increases Po by prolonging the mean burst durations and shortening the interburst durations. We therefore conclude that two different 9-AC binding sites for potentiation and inhibitory effects on CFTR channels are located outside of the R-domain. We also speculate that 9-AC potentiates CFTR activity by directly affecting CFTR gating. PMID:15290302

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

    NASA Astrophysics Data System (ADS)

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

    2014-06-01

    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.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. Electronic supplementary information (ESI) available: Synthesis details, SEM and additional HR-TEM images, FT-IR spectra, EDAX microanalysis and pore distribution of loaded MCM41@anth. See DOI: 10.1039/c3nr06669j

  15. 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

  16. 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…

  17. 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...

  18. 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...

  19. 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...

  20. 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

  1. 7,12-DIMETHYLBENZ[A]ANTHRACENE-INDUCED MODULATION OF CYTOKINES INVOLVED IN CYTOTOXIC T LYMPHOCYTE INDUCTION

    EPA Science Inventory

    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 lymp...

  2. 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. PMID:27224055

  3. 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

  4. 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

  5. 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

  6. 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.

  7. 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.

  8. 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

  9. Anthracene-terpyridine metal complexes as new G-quadruplex DNA binders.

    PubMed

    Gama, Sofia; Rodrigues, Inês; Mendes, Filipa; Santos, Isabel C; Gabano, Elisabetta; Klejevskaja, Beata; Gonzalez-Garcia, Jorge; Ravera, Mauro; Vilar, Ramon; Paulo, António

    2016-07-01

    The formation of quadruple-stranded DNA induced by planar metal complexes has particular interest in the development of novel anticancer drugs. This is especially relevant for the inhibition of telomerase, which plays an essential role in cancer cell immortalization and is overexpressed in ca. 85-90% of cancer cells. Moreover, G-quadruplexes also exist in other locations in the human genome, namely oncogene promoter regions, and it has been hypothesized that they play a regulatory role in gene transcription. Herein we report a series of new anthracene-containing terpyridine ligands and the corresponding Cu(II) and Pt(II) complexes, with different linkers between the anthracenyl moiety and the terpyridine chelating unit. The interaction of these ligands and metal complexes with different topologies of DNA was studied by several biophysical techniques. The Pt(II) and Cu(II) complexes tested showed affinity for quadruplex-forming sequences with a good selectivity over duplex DNA. Importantly, the free ligands do not have significant affinity for any of the DNA sequences used, which shows that the presence of the metal is essential for high affinity (and selectivity). This effect is more evident in the case of the Pt(II) complexes. Moreover, the presence of a longer linker between the chelating terpyridine unit and the anthracene moiety enhances the interaction with G-quadruplex-forming sequences. We further evaluated the ability of the Cu(II) complexes to interact with, and stabilize G-quadruplex containing regions in oncogene promoters via a polymerase stop assay. These studies indicated that the metal complexes are able to induce G-quadruplex formation and stop polymerase activity. PMID:27267415

  10. Photocontrol over the Disorder-to-Order Transition (DOT) in Thin Film of Polystyrene-block-Poly(methyl methacrylate) Block Copolymers Containing Photodimerizable anthracene functionality

    NASA Astrophysics Data System (ADS)

    Chen, Wei; Li, Le; Wei, Xinyu; Balazs, Anna; Matyjaszewski, Krzysztof; Russell, Thomas

    2010-03-01

    Reversible photocontrol over the disorder-to-order transition (DOT) of block copolymers can be used to fabricate defect-free, long-range ordered nanomaterials over macroscopic distances by ``photo-combing'' the microdomains. Here, we randomly copolymerized anthracene functionalities in a ``dilute'' way with 2-hydroxyethyl methacrylate as the middle block, forming deuterated polystyrene-block-poly(2-(methacryloyloxy)ethyl anthracene-9-carboxylate-random-2-hydroxyethyl methacrylate)-block-poly(methyl methacrylate) (d8-PS-b-P(9AnEMA-r-HEMA)-b-PMMA) triblock copolymers. Upon UV irradiation of a thin film of the phase-mixed triblock copolymer, photodimerization of anthracene links the junction of d8-PS and PMMA blocks and produces an artificial interface to force a phase-separation, i.e. a UV-induced DOT, as evidenced by small angle neutron scattering (SANS). Reversible photocontrol over the DOT can be achieved by taking advantage of photodimerization and photodissociation of anthracene.

  11. 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. PMID:26919259

  12. 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

  13. 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

  14. 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

  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. PMID:27500974

  16. 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.

  17. New diagnostic ratios based on phenanthrenes and anthracenes for effective distinguishing heavy fuel oils from crude oils.

    PubMed

    Zhang, Haijiang; Wang, Chuanyuan; Zhao, Ruxiang; Yin, Xiaonan; Zhou, Hongyang; Tan, Liju; Wang, Jiangtao

    2016-05-15

    The heavy fuel oils (HFOs) and crude oils are the main oil types in the marine oil spill accidents in China. It is usually a challenge to distinguish the HFOs from crude oils due to the highly similar physicochemical characteristics. In this paper, the distributions of phenanthrene (Phe), anthracene (Ant), methyl-phenanthrene (MP) and methyl-anthracene (MA) in hundreds of HFOs and crude oils samples which were collected from all over the world were characterized. Nine new diagnostic indexes, such as Ant/(Ant+Phe) and other eight diagnostic ratios based on the MP isomers and MA, were developed for effective distinguishing HFOs from crude oils. The histogram with normal fit plots, the double ratio plots and Bayes discriminant analysis (BDA) method were employed to illustrate the effectiveness of the new diagnostic indexes. BDA model based on nine new diagnostic indexes demonstrated high precision with discriminant ratio which lay between 93.92% and 99.32%. PMID:27016330

  18. Aerobic oxidation of anthracene in the presence of manganese porphyrinates and NaBH/sub 4/ reducing agent

    SciTech Connect

    Lukashova, E.A.; Solov'ev, A.B.; Chugreev, A.L.; Enikolopyan, N.S.

    1987-12-01

    The authors investigate the kinetics of anthracene oxidation by molecular oxygen in the presence of manganese, iron, and cobalt porphyrinate catalysts and a sodium borohydride reducing agent at room temperature in solutions of ethanol or ethanol with chloroform and benzene. Effective rate constants for the reactions are determined based on the amount of anthraquinone formed in the reaction. In all cases with the exception of cobalt tetraphenylporphyrinate the only oxidation product was anthraquinone. Its structure was verified by NMR and IR spectroscopy.

  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. 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

  1. 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

  2. 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.

  3. 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

  4. Anthracene and pyrene photolysis kinetics in aqueous, organic, and mixed aqueous-organic phases

    NASA Astrophysics Data System (ADS)

    Grossman, Jarod N.; Stern, Adam P.; Kirich, Makena L.; Kahan, Tara F.

    2016-03-01

    Condensed phases in the atmosphere, such as cloud droplets and aerosols, often contain both water and organic matter (OM). Reactivity can differ significantly between aqueous and organic phases. We have measured photolysis kinetics of the polycyclic aromatic hydrocarbons (PAHs) anthracene and pyrene in several organic solvents and in water, as well as in miscible and phase-separated aqueous-organic mixtures at atmospherically-relevant wavelengths. Photolysis rate constants generally increased with increasing solvent polarity; photolysis of both PAHs was more than ten times faster in water than in octanol. Local polarity had a much greater effect on PAH photolysis kinetics than changes in PAH absorptivity or singlet oxygen concentrations. Photolysis kinetics in homogeneous aqueous-organic mixtures varied monotonically with2 OM volume fraction. Kinetics in immiscible (phase-separated) solutions were more complex, with different dependences on OM content observed in stagnant and turbulent solutions. Our results suggest that OM could greatly affect the photochemical lifetimes of PAHs in atmospheric condensed phases such as aerosols, even if the OM does not itself absorb photons.

  5. Biodegradation of anthracene and fluoranthene by fungi isolated from an experimental constructed wetland for wastewater treatment.

    PubMed

    Giraud, F; Guiraud, P; Kadri, M; Blake, G; Steiman, R

    2001-12-01

    Pilot-scale constructed wetlands were used to treat water contaminated by polycyclic aromatic hydrocarbons (PAHs), particularly fluoranthene, and the possible role of fungi present in these ecosystems was investigated. A total of 40 fungal species (24 genera) were isolated and identified from samples (gravel and sediments) from a contaminated wetland and a control wetland. All of them were assayed for their ability to remove anthracene (AC) and fluoranthene (FA) from liquid medium. FA was degraded efficiently by 33 species while only 2 species were able to remove AC over 70%. A selection of 10 strains of micromycetes belonging to various taxonomic groups was further investigated for FA and AC degradation, toxicity assays and phenoloxidases (POx) detection. Interesting and not previously reported species were revealed (Absidia cylindrospora, Cladosporium sphaerospermum, and Ulocladium chartarum). They were all able to highly degrade the PAH-model compounds chosen. An interesting inducibility was noted for Ulocladium chartarum. Degradative ability of fungi was not related to their extracellular POx activity. This study may contribute to the improvement of constructed wetlands for water treatment, which may be enriched in efficient fungi. PMID:11791842

  6. 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.

  7. Cell metabolic changes of porphyrins and superoxide anions by anthracene and benzo(a)pyrene.

    PubMed

    Uribe-Hernández, Raúl; Pérez-Zapata, Aura J; Vega-Barrita, María L; Ramón-Gallegos, Eva; Amezcua-Allieri, Myriam A

    2008-09-01

    The aim of this work was to evaluate the induction of protoporphyrins IX (PpIX) activity and superoxide anions (SO) in human leukocytes exposed to anthracene (ANT) and benzo(a)pyrene (B(a)P). The leukocyte LC(50)s for both hydrocarbons and the PpIX accumulation and SO overproduction were measured. The LC(50)s were 0.35 and 3.23μM for ANT and B(a)P, respectively. A linear relationship (r=0.97, p<0.01) between PpIX and ANT concentration was obtained. The induced accumulation of PpIX was proportional (r=0.63, p<0.01) to B(a)P concentration. SO overproduction showed a linear relationship (r=0.83, p<0.05) with ANT concentrations. The linear regression analysis of the effect of B(a)P on the superoxide anion overproduction showed a good coefficient (r=0.97, p<0.01), showed that ANT and B(a)P exposure induces PpIX accumulation, probably by disruption of the haem biosynthesis. ANT and B(a)P induce SO overproduction, perhaps through a process of redox cycling. PMID:21791370

  8. 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.

  9. 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

  10. 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

  11. 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.

  12. Obtaining the lattice energy of the anthracene crystal by modern yet affordable first-principles methods

    NASA Astrophysics Data System (ADS)

    Sancho-García, J. C.; Aragó, J.; Ortí, E.; Olivier, Y.

    2013-05-01

    The non-covalent interactions in organic molecules are known to drive their self-assembly to form molecular crystals. We compare, in the case of anthracene and against experimental (electronic-only) sublimation energy, how modern quantum-chemical methods are able to calculate this cohesive energy taking into account all the interactions between occurring dimers in both first-and second-shells. These include both O(N6)- and O(N5)-scaling methods, Local Pair Natural Orbital-parameterized Coupled-Cluster Single and Double, and Spin-Component-Scaled-Møller-Plesset perturbation theory at second-order, respectively, as well as the most modern family of conceived density functionals: double-hybrid expressions in several variants (B2-PLYP, mPW2-PLYP, PWPB95) with customized dispersion corrections (-D3 and -NL). All-in-all, it is shown that these methods behave very accurately producing errors in the 1-2 kJ/mol range with respect to the experimental value taken into account the experimental uncertainty. These methods are thus confirmed as excellent tools for studying all kinds of interactions in chemical systems.

  13. 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

  14. 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.

  15. 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.

  16. 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

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

    SciTech Connect

    Schuster, Patricia; Brubaker, Erik

    2016-01-01

    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 of 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.

  18. 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.

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

    PubMed

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

    2016-03-15

    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. PMID:26720419

  20. 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

  1. 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.

  2. 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.

  3. 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.

  4. 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. PMID:19606432

  5. 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

  6. 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

  7. 7,12-Dimethylbenz[a]anthracene-Induced Malignancies in a Mouse Model of Menopause

    PubMed Central

    Marion, Samuel L; Watson, Jennifer; Sen, Nivedita; Brewer, Molly A; Barton, Jennifer K; Hoyer, Patricia B

    2013-01-01

    Ovarian cancer has a high mortality rate because there are few symptoms in early disease development. The incidence of ovarian cancer increases in women after menopause. Understanding early events in this disease can best be achieved by using animal models. Therefore, the objective of this study was to develop and track the onset of ovarian tumorigenesis in mice mimicking characteristics of postmenopausal epithelial cancer in women. Female B6C3F1 mice (age, 28 d) received 4-vinylcyclohexene diepoxide (VCD, 160 mg/kg IV daily for 20 d) to cause ovarian failure. Four months after VCD treatment, via surgical intervention, each mouse received a single injection of 7,12-dimethylbenz[a]anthracene (DMBA) or vehicle control (sesame oil) under the bursa of the right ovary to cause ovarian neoplasms. The experimental groups were untreated controls (Con–Con), DMBA-treatment only (Con–DMBA), VCD treatment only (VCD–Con), and VCD+DMBA-treated (VCD+DMBA) mice. At 3, 5, 7, and 9 mo after DMBA injection, ovaries were collected for histologic and immunohistochemical evaluation. No tumors developed in Con–Con mice. All VCD-treated mice (with or without DMBA) exhibited ovarian failure. Mice that received both VCD and DMBA exhibited tumors at 3 mo (50%), 5 mo (14%), 7 mo (90%), and 9 mo (57%) after DMBA treatment; 31% of the tumors were epithelial in origin. Our findings confirm that inducing ovarian tumors in mice by chemical means is an effective method for studying early stages of tumor development that may be relevant to epithelial ovarian cancers that arise in postmenopausal women. PMID:23561932

  8. 7,12-dimethylbenz[a]anthracene-induced malignancies in a mouse model of menopause.

    PubMed

    Marion, Samuel L; Watson, Jennifer; Sen, Nivedita; Brewer, Molly A; Barton, Jennifer K; Hoyer, Patricia B

    2013-02-01

    Ovarian cancer has a high mortality rate because there are few symptoms in early disease development. The incidence of ovarian cancer increases in women after menopause. Understanding early events in this disease can best be achieved by using animal models. Therefore, the objective of this study was to develop and track the onset of ovarian tumorigenesis in mice mimicking characteristics of postmenopausal epithelial cancer in women. Female B6C3F1 mice (age, 28 d) received 4-vinylcyclohexene diepoxide (VCD, 160 mg/kg IV daily for 20 d) to cause ovarian failure. Four months after VCD treatment, via surgical intervention, each mouse received a single injection of 7,12-dimethylbenz[a]anthracene (DMBA) or vehicle control (sesame oil) under the bursa of the right ovary to cause ovarian neoplasms. The experimental groups were untreated controls (Con-Con), DMBA-treatment only (Con-DMBA), VCD treatment only (VCD-Con), and VCD+DMBA-treated (VCD+DMBA) mice. At 3, 5, 7, and 9 mo after DMBA injection, ovaries were collected for histologic and immunohistochemical evaluation. No tumors developed in Con-Con mice. All VCD-treated mice (with or without DMBA) exhibited ovarian failure. Mice that received both VCD and DMBA exhibited tumors at 3 mo (50%), 5 mo (14%), 7 mo (90%), and 9 mo (57%) after DMBA treatment; 31% of the tumors were epithelial in origin. Our findings confirm that inducing ovarian tumors in mice by chemical means is an effective method for studying early stages of tumor development that may be relevant to epithelial ovarian cancers that arise in postmenopausal women. PMID:23561932

  9. 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.

  10. 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.

  11. 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

  12. Mono- and Dinuclear Manganese Carbonyls Supported by 1,8-Disubstituted (L = Py, SMe, SH) Anthracene Ligand Scaffolds.

    PubMed

    Manes, Taylor A; Rose, Michael J

    2016-06-01

    Presented herein is a synthetic scheme to generate symmetric and asymmetric ligands based on a 1,8-disubstituted anthracene scaffold. The metal-binding scaffolds were prepared by aryl chloride activation of 1,8-dichloroanthracene using Suzuki-type couplings facilitated by [Pd(dba)2] as a Pd source; the choice of cocatalyst (XPhos or SPhos) yielded symmetrically or asymmetrically substituted scaffolds (respectively): namely, Anth-SMe2 (3), Anth-N2 (4), and Anth-NSMe (6). The ligands exhibit a nonplanar geometry in the solid state (X-ray), owing to steric hindrance between the anthracene scaffold and the coupled aryl units. To determine the flexibility and binding characteristics of the anthracene-based ligands, the symmetric scaffolds were complexed with [Mn(CO)5Br] to afford the mononuclear species [(Anth-SMe2)Mn(CO)3Br] (8) and [(Anth-N2)Mn(CO)3Br] (9), in which the donor moieties chelate the Mn center in a cis fashion. The asymmetric ligand Anth-NSMe (6) binds preferentially through the py moieties, affording the bis-ligated complex [(Anth-NSMe)2Mn(CO)3Br] (10), wherein the thioether-S donors remain unbound. Alternatively, deprotection of the thioether in 6 affords the free thiol ligand Anth-NSH (7), which more readily binds the Mn center. Complexation of 7 ultimately affords the mixed-valence Mn(I)/Mn(II) dimer of formula [(Anth-NS)3Mn2(CO)3] (11), which exhibits a fac-{Mn(CO)3} unit supported by a triad of bridging thiolates, which are in turn ligated to a supporting Mn(II) center (EPR: |D| = 0.053 cm(-1), E/|D| = 0.3, Aiso = -150 MHz). All of the metal complexes have been characterized by single-crystal X-ray diffraction, IR spectroscopy and NMR/EPR measurements-all of which demonstrate that the meta-linked, anthracene-based ligand scaffold is a viable approach for the coordination of metal carbonyls. PMID:27195661

  13. Electron-Phonon Coupling and CT-Character in the lowest Triplet Excited State of Anthracene EDA-Complex Crystals

    NASA Astrophysics Data System (ADS)

    Maier, S.; Port, H.

    1987-11-01

    Photoexcitation spectra of triplet (T1← S0) zero-phonon lines and phonon sidebands in different anthracene electron donor-acceptor (EDA) complex crystals (A-PMDA, A-TCNB, A-TCPA) have been analyzed between 1.3 K and 50 K at high spectral resolution. From the electron-phonon coupling strength at T = 0 K values of the charge-transfer (CT) character in the range between 6% and 10% are calculated. The differences in these values are found to be correlated with the energetic positions of the triplet state, which are explained within the framework of the Mulliken theory.

  14. 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.

  15. Facile synthesis of single-crystalline microwires based on anthracene derivative and their efficient optical waveguides and linearly polarized emission

    NASA Astrophysics Data System (ADS)

    Peng, Hong-Dan; Wang, Juan-Ye; Liu, Zheng-Hui; Pan, Ge-Bo

    2016-05-01

    The well-defined single-crystalline microwires of a solid-emissive organic functional molecule, 2-(anthracen-9-yl)-4, 5-diphenyl-1H-imidozole (ADPI) were successfully prepared by a facile solution process without the use of surfactant or additional templates. In addition, the optical loss coefficient is as low as 0.1 dB μm-1 for the as-prepared ADPI microwires, which is lower than most previous reported organic optical waveguides. Meanwhile, these microwires also show optically uniaxial properties as demonstrated by the linearly polarized emission, providing potentially orientation-sensitive applications as optical waveguides with low optical loss.

  16. 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.

  17. Hybrid light-emitting diodes from anthracene-contained polymer and CdSe/ZnS core/shell quantum dots

    NASA Astrophysics Data System (ADS)

    Tu, Ming-Lung; Su, Yan-Kuin; Chen, Ruei-Tang

    2014-11-01

    In this paper, we added CdSe/ZnS core/shell quantum dots (QDs) into anthracene-contained polymer. The photoluminescent (PL) characteristic of polymer/QD composite film could identify the energy transitions of anthracene-contained polymer and QDs. Furthermore, the electroluminescent (EL) characteristic of hybrid LED also identifies emission peaks of blue polymer and QDs. The maximum luminescence of the device is 970 cd/m2 with 9.1 wt.% QD hybrid emitter. The maximum luminous efficiency is 2.08 cd/A for the same device.

  18. 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.

  19. 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.

  20. 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.

  1. 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. PMID:25779113

  2. Oxidative DNA damage induced by benz[a]anthracene dihydrodiols in the presence of dihydrodiol dehydrogenase.

    PubMed

    Seike, Kazuharu; Murata, Mariko; Hirakawa, Kazutaka; Deyashiki, Yoshihiro; Kawanishi, Shosuke

    2004-11-01

    Tobacco smoke and polluted air are risk factors for lung cancer and contain many kinds of polycyclic aromatic hydrocarbons (PAHs) including benzo[a]pyrene (B[a]P) and benz[a]anthracene (BA). BA, as well as B[a]P, is assessed as probably carcinogenic to humans (IARC group 2A). BA is metabolized to several dihydrodiols. Dihydrodiol dehydrogenase (DD), a member of the aldo-keto reductase superfamily, catalyzes NAD(P)+-linked oxidation of dihydrodiols of aromatic hydrocarbons to corresponding catechols. To clarify the role of DD on PAH carcinogenesis, we examined oxidative DNA damage induced by trans-dihydrodiols of BA and B[a]P treated with DD using 32P-5'-end-labeled DNA fragments obtained from the human p53 tumor suppressor gene. In addition, we investigated the formation of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), an indicator of oxidative DNA damage, in calf thymus DNA by using HPLC with an electrochemical detector. DD-catalyzed BA-1,2-dihydrodiol caused Cu(II)-mediated DNA damage including 8-oxodG formation in the presence of NAD+. BA-1,2-dihydrodiol induced a Fpg sensitive and piperidine labile G lesion at the 5'-ACG-3' sequence complementary to codon 273 of the human p53 tumor suppressor gene, which is known as a hotspot. DNA damage was inhibited by catalase and bathocuproine, suggesting the involvement of H2O2 and Cu(I). The observation of NADH production by UV-visible spectroscopy suggested that DD catalyzed BA-1,2-dihydrodiol most efficiently to the corresponding catechol among the PAH-dihydrodiols tested. A time-of-flight mass spectroscopic study showed that the catechol form of BA-1,2-dihydrodiol formed after DD treatment. In conclusion, BA-1,2-dihydrodiol can induce DNA damage more efficiently than B[a]P-7,8-dihydrodiol and other BA-dihydrodiols in the presence of DD. The reaction mechanism on oxidative DNA damage may be explained by theoretical calculations with an enthalpy change of dihydrodiols and oxidation potential of their catechol forms. DD

  3. Impact of obesity on ovotoxicity induced by 7,12-dimethylbenz[a]anthracene in mice.

    PubMed

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

    2014-03-01

    Insulin, elevated during obesity, regulates xenobiotic biotransformation enzymes, potentially through phosphatidylinositol 3-kinase (PI3K) signaling, in extraovarian tissues. PI3K regulates oocyte viability, follicular activation, and ovarian chemical biotransformation. 7,12-Dimethylbenz[a]anthracene (DMBA), a carcinogen and ovotoxicant, destroys all stages of follicles, leading to premature ovarian failure. Obesity has been reported to promote DMBA-induced tumors, but it remains unknown whether obesity affects ovarian xenobiotic metabolism. Therefore, we investigated ovarian expression of xenobiotic metabolism genes-microsomal epoxide hydrolase (Ephx1), glutathione S-transferase (GST) class Pi (Gstp1) and class mu 1 (Gstm1), and PI3K-signaling members (protein kinase B [AKT] alpha [Akt1], beta [Akt2], and the forkhead transcription factor subfamily 3 [Foxo3])-in lean and obese female mice after DMBA exposure (1 mg/kg; intraperitoneal injection for 14 days). Relative to lean, obese mice had decreased (P < 0.05) healthy primordial and primary follicle numbers but increased (P < 0.05) secondary and preovulatory follicles numbers. Obesity increased (P < 0.05) Akt1, Akt2, Gstm1, and Ephx1 mRNA and pAKT(Ser473/Thr308), GSTM1, GSTP1, and EPHX1 protein levels. DMBA decreased (P < 0.05) ovarian weight in lean and obese mice, however, obese DMBA-treated females had a greater reduction (P < 0.05) in ovarian weight. In both lean and obese mice, DMBA decreased (P < 0.05) all stages of healthy follicle numbers, increased Gstp1 and Ephx1 mRNA as well as GSTM1, GSTP1, and EPHX1 protein levels, and decreased Akt1 and Akt2 mRNA as well as pAKT(Ser473) or pAKT(Thr308), FOXO3, and pFOXO3(Ser253) protein expression. There was an additive effect between obesity and DMBA exposure for increased Gstm1 and Ephx1 mRNA as well as GSTM1 and EPHX1 protein expression. PMID:24501177

  4. 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...

  5. EFFECTS OF SEX AND AGE ON DMBA:DNA BINDING IN EPIDERMIS OF SENCAR MICE FOLLOWING TOPICAL ADMINISTRATION OF DIMETHYLBENZ(A) ANTHRACENE

    EPA Science Inventory

    Epidermal DMBA+DNA adduct formation was determined in male and female SENCAR mice following short-term exposure to 7,12-dimethylbenz(a)anthracene (DMBA). While no differences in the proportions of the individual adducts were found between male and female mice, male mice generally...

  6. 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...

  7. EFFECTS OF 7,12-DIMETHYLBENZ[A]ANTHRACENE ON IMMUNE FUNCTION AND MIXED-FUNCTION OXYGENASE ACTIVITY IN THE EUROPEAN STARLING

    EPA Science Inventory

    Immune function and hepatic mixed-function oxygenase (MFO) activity were xamined in adult and nestling starlings administered a synthetic PAH, 7,12dimethylbenz[a]anthracene (DMBA). ethods used to examine the starling immune system included immunopathology, macrophage phagocytosis...

  8. 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

  9. Reactivity of anthracene in liquid SbCl/sub 3/-AlCl/sub 3/-N-(1-BUTYL)pyridinium chloride mixtures

    SciTech Connect

    Zingg, S.P.; Buchanan, A.C.; Chapman, D.M.; Dworkin, A.S.; Smith, G.P.; Sorlie, M.

    1983-05-01

    Mixtures of SbCl/sub 3/ and N-(1-butyl)pyridinium chloride (BPCl) containing 75-87 mol % SbCl/sub 3/ and SbCl/sub 3/-AlCl/sub 3/-BPCl mixtures containing 60 mol % SbCl/sub 3/ and 17-24 mol % BPCl were found to be liquid at 25/sup 0/C. Dilute solutions of anthracene were stable in ternary mixtures containing 18 mol % AlCl/sub 3/, but in mixtures containing 22-24 mol % AlCl/sub 3/, anthracene reacted under the influence of the solvent, which behaved as both oxidant and H-transfer catalyst. The oxidized product was protonated anthracene, which was stable in this melt. The source of protons was provided by hydrogen-liberating Scholl condensations combined with the reduction of Sb(III). A part of the hydrogen from Scholl reactions reacted with anthracene to form 9,10-dihydroanthracene. By contrast, a liquid mixture without SbCl/sub 3/, AlCl/sub 3/-BPCl (2:1 mole ratio), proved to be a much less active H-transfer catalyst than the SbCl/sub 3/-rich liquids even though it is a stronger Lewis acid, and it did not induce protonation beyond a trace attributable to protic impurities.

  10. Reactivity of anthracene in liquid SbCl/sub 3/-AlCl/sub 3/-N-(1-butyl)pyridinium chloride mixtures

    SciTech Connect

    Zingg, S.P.; Dworkin, A.S.; Sorlie, M.; Chapman, D.M.; Buchanan, A.C. III; Smith, G.P.

    1983-01-01

    Mixtures of SbCl/sub 3/ and N-(1-butyl)pyridinium chloride (BPCl) containing 75 to 87 mol % SbCl/sub 3/ and SbCl/sub 3/-AlCl/sub 3/-BPCl mixtures containing 60 mol % SbCl/sub 3/ and 17 to 24 mol % BPCl were found to be liquid at 25/sup 0/C. Dilute solutions of anthracene were stable in ternary mixtures containing 18 mol % AlCl/sub 3/, but in mixtures containing 22 to 24 mol % AlCl/sub 3/, anthracene reacted under the influence of the solvent, which behaved as both oxidant and H-transfer catalyst. The oxidized product was protonated anthracene, which was stable in this melt. The source of protons was provided by hydrogen-liberating Scholl condensations combined with the reduction of Sb(III). A part of the hydrogen from Scholl reactions reacted with anthracene to form 9,10-dihydroanthracene. By contrast, a liquid mixture without SbCl/sub 3/, AlCl/sub 3/-BPCl (2:1 mole ratio), proved to be a much less active H-transfer catalyst than the SbCl/sub 3/-rich liquids even though it is a stronger Lewis acid, and it did not induce protonation beyond a trace attributable to protic impurities.

  11. 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

  12. 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

  13. 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. PMID:25688524

  14. Intramolecular Interaction, Photoisomerization, and Mechanical C-C Bond Dissociation of 1,2-Di(9-anthryl)benzene and Its Photoisomer: A Fundamental Moiety of Anthracene-Based π-Cluster Molecules.

    PubMed

    Nishiuchi, Tomohiko; Uno, Shin-Ya; Hirao, Yasukazu; Kubo, Takashi

    2016-03-01

    We report variable and unique properties of 1,2-di(9-anthryl)benzene 1 as a fundamental moiety of anthracene-based π-cluster molecules. Due to a through-space π-conjugation between anthracene units, excimer emission at room temperature and charge delocalized state in radical cation state of 1 could be observed. Photoirradiation to 1 afforded an intramolecular [4 + 4] cyclized anthracene dimer 1' having a high strain energy with long C-C bond that exceeded 1.68 Å, resulting in C-C bond dissociation by simple mechanical grinding. PMID:26828776

  15. Enhanced photostability of the anthracene chromophore in aqueous medium upon protein encapsulation.

    PubMed

    Alonso, Rafael; Yamaji, Minoru; Jiménez, M Consuelo; Miranda, Miguel A

    2010-09-01

    In the present work, 9-anthraceneacetic acid (1) has been selected as a simple, water-compatible derivative of the anthracene chromophore to investigate the photophysical and photochemical behavior upon binding to human and bovine serum albumins (HSA and BSA) and alpha-acid glycoproteins (HAAG and BAAG). The UV-vis absorption spectrum of 1 exhibited the typical four maxima between 320 and 400 nm, which were slightly red-shifted in the presence of proteins. These minor changes suggested the formation of 1@protein complexes; their stoichiometry (1:1) was determined by means of the corresponding Job plots. As expected, the fluorescence spectrum of 1 in phosphate-buffered saline (PBS) consisted of a structured emission with maxima between 390 and 470 nm. The addition of increasing amounts of HSA resulted in a decrease in the emission intensity. In the presence of BSA, HAAG, or BAAG, the same trend was observed, although the changes were less pronounced. The determination of binding constants was achieved from fluorescence titration, considering one (AAGs) or two (SAs) binding sites. The binding constants (K(B)) were found to be 2.3 x 10(6) M(-1) (HAAG), 2.4 x 10(6) M(-1) (BAAG), 4.57 x 10(4)/1.45 x 10(6) M(-1) (HSA), and 1.44 x 10(4)/1.20 x 10(6) M(-1) (BSA). Binding within two different sites of SAs was confirmed by displacement experiments using warfarin and ibuprofen as site I and site II probes, respectively. Laser flash photolysis of 1 at lambda(exc) = 355 nm in PBS/air gave rise to several transient species; by contrast, in the presence of 1 equiv of proteins, only the triplet excited state was detected. Moreover, the triplet lifetime (tau(T)) monitored at 420 nm lengthened considerably (up to 50-fold) in the protein media. This can be attributed to a slower deactivation of the species inside the protein binding pockets, where an exceptional microenvironment provides protection from attack by a second molecule of 1, oxygen, or other reagents. In agreement with

  16. 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). PMID:16839225

  17. Effect of Rosmarinus officinalis in modulating 7,12-dimethylbenz(a)anthracene induced skin tumorigenesis in mice.

    PubMed

    Sancheti, Garima; Goyal, P K

    2006-11-01

    The chemopreventive potential of rosemary (Rosmarinus officinalis) on 7,12-dimethlybenz(a)anthracene (DMBA) initiated and croton oil promoted mouse skin tumorigenesis was assessed. The modulatory effects of R. officinalis was monitored on the basis of the average latency period, tumor incidence, tumor burden, tumor yield, tumor weight and diameter as well as lipid peroxidation and glutathione level. The results indicate that R. officinalis leaves extract could prolong the latency period of tumor occurrence, decrease the tumor incidence, tumor burden and tumor yield. The average weight and diameter of tumors recorded were comparatively lower in the rosemary extract treated mouse groups. The level of lipid peroxidation was significantly reduced in blood serum and liver. Furthermore, depleted levels of glutathione were restored in RE-administered animal groups. Thus, at a dose rate of 500 mg/kg body wt/mouse, the oral administration of rosemary extract was found to be significantly protective against two-stage skin tumorigenesis. PMID:16927448

  18. 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%.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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

  5. 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

  6. [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

  7. 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

  8. 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

  9. 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.

  10. Reactivity of anthracene in liquid SbCl/sub 3/-AlCl/sub 3/-N-(1-butyl)pyridinium chloride mixtures

    SciTech Connect

    Zingg, S.P.; Buchanan, A.C.; Chapman, D.M.; Dworkin, A.S.; Smith, G.P.; Sorlie, M.

    1984-07-01

    Mixtures of SbCl/sub 3/ and N-(l-butyl)pyridinium chloride (BPCl) containing 75-87 m/o (mole percent) SbCl/sub 3/ and SbCl/sub 3/AlCl/sub 3/-BPCl mixtures containing 60 m/o SbCl/sub 3/ and 16-23 m/o AlCl/sub 3/ were found to be liquid at 25/sup 0/C. Dilute solutions of anthracene were stable in ternary mixtures containing 18 m/o AlCl/sub 3/, but in mixtures containing 22-24 m/o AlCl/sub 3/, anthracene reacted under the influence of the solvent, which behaved as both oxidant and H-transfer catalyst. The oxidized product was protonated anthracene, which was stable in this melt. The source of protons was provided by hydrogen liberating Scholl condensations combined with the reduction of Sb(III). A part of the hydrogen from Scholl reactions reacted with anthracene to form 9,10-dihydroanthracene. By contrast, a liquid mixture without SbCl/sub 3/, AlCl/sub 3/-BPCl (2:1 mole ratio) proved to be a much less active H-transfer catalyst than the SbCl/sub 3/-rich liquids even though it is a stronger Lewis acid, and it did not induce protonation beyond a trace attributable to protic impurities. The role of impurities in these mixtures was investigated with results that are relevant to earlier investigations of liquid AlCl/sub 3/-BPCl mixtures. An improved procedure for purifying BPCl is described.

  11. 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.

  12. Anthracene excimer-based "turn on" fluorescent sensor for Cr(3+) and Fe(3+) ions: Its application to living cells.

    PubMed

    Erdemir, Serkan; Kocyigit, Ozcan

    2016-09-01

    A novel anthracene based fluorescent probe containing benzothiazole group (BFA) was designed and synthesized. The cation binding properties of BFA were studied in the presence of various cations. Both UV-vis and fluorescence spectroscopic studies indicated that BFA was highly sensitive and selective toward trivalent cations (Cr(3+) and Fe(3+)), while there was no response to monovalent, divalent cations and also Al(3+) ion. The interaction of BFA with Cr(3+) and Fe(3+) caused a significant enhancement in emission intensity due to the combination of a unique anthracenyl static excimer formation, the restricted C=N isomerization and the suppression of highly efficient photoinduced electron transfer (PET) process. The detection limits of BFA for Cr(3+) and Fe(3+) were 0.46 and 0.45µM, which presented a pronounced sensitivity toward Cr(3+) and Fe(3+), respectively. Also, possible utilization of BFA as bio-imaging fluorescent probe to detect Cr(3+) and Fe(3+) in human prostate cancer cell lines was observed by confocal fluorescence microscopy. PMID:27343579

  13. 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

  14. Fluorescence behaviour of an anthracene-BODIPY system affected by spin states of a dioxolene-cobalt centre.

    PubMed

    Katayama, Koichi; Hirotsu, Masakazu; Ito, Akitaka; Teki, Yoshio

    2016-06-21

    Dioxolene cobalt complexes, [Co(L)(TPA)]PF6 () and [Co(L)(Me3TPA)]PF6 (), were synthesized using a catechol with anthracene and boron-dipyrromethene (BODIPY), H2L, and tris(pyridin-2-ylmethyl)amine (TPA) or tris[(6-methylpyridin-2-yl)methyl]amine (Me3TPA) and characterised by UV-vis absorption, IR and NMR spectroscopy. Complexes and are a low-spin cobalt(iii) catecholate form and a high-spin cobalt(ii) semiquinonate form, respectively, in CH3CN at room temperature. The effect of the spin states of the dioxolene-cobalt centre on fluorescence was investigated in CH3CN at room temperature. The fluorescence intensity of was clearly lower than that of , although both complexes showed weaker fluorescence compared with that of H2L. The difference in the intensity between and is mainly due to the enhancement of nonradiative decay processes based on the stronger metal-ligand interactions for the cobalt(iii) catecholate form of compared with the cobalt(ii) semiquinonate form of . PMID:27075418

  15. 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

  16. Black tea polyphenols protect against 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis.

    PubMed

    Letchoumy, P Vidjaya; Chandra Mohan, K V P; Kumaraguruparan, R; Hara, Y; Nagini, S

    2006-01-01

    Dietary chemoprevention has emerged as a cost-effective approach for cancer control. We evaluated the chemopreventive effects of black tea polyphenols (Polyphenon-B) administration during the preinitiation phase of 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis. The expression of proliferating cell nuclear antigen (PCNA) in the buccal pouch and the concentration of lipid peroxides, protein carbonyl, and the antioxidant status in the buccal pouch, liver and erythrocytes were used as biomarkers of chemoprevention. All the hamsters painted with DMBA alone for 14 weeks developed buccal pouch carcinomas associated with increased expression of PCNA, diminished lipid and protein oxidation, and enhanced antioxidant status. In the liver and erythrocytes of tumor-bearing animals, enhanced oxidation of lipids and proteins was accompanied by compromised antioxidant defenses. Dietary administration of Polyphenon-B effectively suppressed DMBA-induced HBP carcinogenesis as revealed by decreased incidence of tumours and PCNA expression. In addition, Polyphenon-B modulated lipid and protein oxidation and enhanced the antioxidant status in the pouch, liver, and erythrocytes. We suggest that Polyphenon-B exerts its chemopreventive effects by inhibiting cell proliferation in the target tissue and modulating the oxidant-antioxidant status in the target as well as in host tissues. PMID:17120615

  17. A two excited state model to explain the peculiar photobehaviour of a flexible quadrupolar D-π-D anthracene derivative.

    PubMed

    Carlotti, B; Cesaretti, A; Gentili, P L; Marrocchi, A; Elisei, F; Spalletti, A

    2016-08-17

    The peculiar photobehaviour of a symmetrical arylenevinylene anthracene derivative bearing mild electron donors (alkoxy groups) at the sides of its structure has been fully comprehended through this study. An investigation into the effect of solvent polarity and temperature on the stationary fluorescence spectrum allowed a clear dual emission to be revealed. A further valuable insight was obtained, thanks to the employment of ultrafast spectroscopies. Fluorescence up-conversion measurements and the Time Resolved Area Normalised Spectra analysis provided a clear-cut proof of the presence of two distinct fluorescent states ((1)A* and (1)B*), with (1)A* being responsible for the steady-state emission in highly polar and viscous media. Femtosecond transient absorption spectra were acquired in several organic solvents of different polarity and viscosity. Interestingly, the lifetime of (1)A* was found to be dependent on solvent viscosity whereas the lifetime of (1)B* showed a trend which matches the change in solvent polarity. Indeed, the Density functional theory calculations predicted a structural rearrangement in the fully relaxed lowest excited singlet state. The (1)A* → (1)B* transition is thus likely accompanied by large amplitude motions of the molecular structure, with the (1)B* state also exhibiting a small intramolecular charge transfer character. The investigated flexible quadrupolar D-π-D system arouses therefore great interest as a novel material for applications in organic electronics and photonics. PMID:27499254

  18. 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. PMID:25736374

  19. Terahertz spectroscopy and solid-state density functional theory calculation of anthracene: Effect of dispersion force on the vibrational modes

    SciTech Connect

    Zhang, Feng; Tominaga, Keisuke E-mail: tominaga@kobe-u.ca.jp; Hayashi, Michitoshi E-mail: tominaga@kobe-u.ca.jp Wang, Houng-Wei; Kambara, Ohki; Sasaki, Tetsuo; Nishizawa, Jun-ichi E-mail: tominaga@kobe-u.ca.jp

    2014-05-07

    The phonon modes of molecular crystals in the terahertz frequency region often feature delicately coupled inter- and intra-molecular vibrations. Recent advances in density functional theory such as DFT-D{sup *} have enabled accurate frequency calculation. However, the nature of normal modes has not been quantitatively discussed against experimental criteria such as isotope shift (IS) and correlation field splitting (CFS). Here, we report an analytical mode-decoupling method that allows for the decomposition of a normal mode of interest into intermolecular translation, libration, and intramolecular vibrational motions. We show an application of this method using the crystalline anthracene system as an example. The relationship between the experimentally obtained IS and the IS obtained by PBE-D{sup *} simulation indicates that two distinctive regions exist. Region I is associated with a pure intermolecular translation, whereas region II features coupled intramolecular vibrations that are further coupled by a weak intermolecular translation. We find that the PBE-D{sup *} data show excellent agreement with the experimental data in terms of IS and CFS in region II; however, PBE-D{sup *} produces significant deviations in IS in region I where strong coupling between inter- and intra-molecular vibrations contributes to normal modes. The result of this analysis is expected to facilitate future improvement of DFT-D{sup *}.

  20. Purification and characterization of an extracellular laccase from the anthracene-degrading fungus Fusarium solani MAS2.

    PubMed

    Wu, Yi-Rui; Luo, Zhu-Hua; Kwok-Kei Chow, R; Vrijmoed, L L P

    2010-12-01

    An extracellular laccase was purified from the culture medium of the non-white rot, anthracene-degrading fungal strain Fusarium solani MAS2. Both native PAGE and SDS-PAGE revealed one single band corresponding to a molecular weight of about 72 kDa. Treatment with endoglycosidase H reduced the molecular weight by 12%. The purified laccase maintained stable at pH 3-11 and up to 50 degrees C. The highest activity was detected at pH 3.0 and at 70 degrees C. The enzyme retained 46.2-97.2% of it activity in the presence of 20mM Pb(2+), Ni(2+), Cr(3+), and its activity was enhanced in the presence of 20mM Hg(2+). The laccase retained more than 50% of its activity in the presence of 5% acetone, acetonitrile, dimethyl sulphoxide (DMSO), ethanol and methanol. The kinetic constants (K(m) and k(cat)) showed that 2,6-dimethoxyphenol (DMOP) and 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) diammonium salt (ABTS) were the more effective substrates rather than catechol and guaiacol. The novel properties of this laccase suggest its potential for biotechnological and environmental applications. PMID:20716485

  1. 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.

  2. 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.

  3. Chemopreventive and antioxidant efficacy of (6)-paradol in 7,12-dimethylbenz(a)anthracene induced hamster buccal pouch carcinogenesis.

    PubMed

    Suresh, Kathiresan; Manoharan, Shanmugam; Vijayaanand, Mariadoss Arokia; Sugunadevi, Govindasamy

    2010-01-01

    The present study evaluated the chemopreventive potential of (6)-paradol, a pungent phenolic constituent of ginger, on 7,12-dimethylbenz(a)anthracene (DMBA)-induced hamster buccal pouch carcinogenesis. The mechanistic pathway for the chemopreventive potential of (6)-paradol was evaluated by measuring the status of tumor incidence, volume and burden as well as by analyzing the status of phase II detoxification agents, lipid peroxidation and antioxidants. Oral squamous cell carcinoma was induced in hamster buccal pouches by painting them with 0.5% DMBA in liquid paraffin three times a week for 14 weeks. We observed 100% tumor formation with marked biochemical abnormalities in tumor-bearing animals compared to control animals. Oral administration of 30 mg/kg b.w. (6)-paradol to DMBA-treated hamsters on alternate days from DMBA painting for 14 weeks, significantly reduced the formation of tumors and improved the status of detoxification agents, lipid peroxidation and antioxidants. Therefore, the present study suggests that (6)-paradol has potent chemopreventive, anti-lipid peroxidative and antioxidant potentials as well as a modulating effect on phase II detoxification enzyme and reduced glutathione (GSH) in DMBA-induced hamster buccal pouch carcinogenesis. PMID:21273675

  4. 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

  5. Cellular metabolic energy modulation by tangeretin in 7,12-dimethylbenz(a) anthracene-induced breast cancer

    PubMed Central

    Periyasamy, Kuppusamy; Sivabalan, Venkatachalam; Baskaran, Kuppusamy; Kasthuri, Kannayiram; Sakthisekaran, Dhanapal

    2016-01-01

    Abstract Breast cancer is the leading cause of death among women worldwide. Chemoprevention and chemotherapy play beneficial roles in reducing the incidence and mortality of cancer. Epidemiological and experimental studies showed that naturally-occurring antioxidants present in the diet may act as anticancer agents. Identifying the abnormalities of cellular energy metabolism facilitates early detection and management of breast cancer. The present study evaluated the effect of tangeretin on cellular metabolic energy fluxes in 7,12-dimethylbenz(a) anthracene (DMBA)-induced proliferative breast cancer. The results showed that the activities of glycolytic enzymes significantly increased in mammary tissues of DMBA-induced breast cancer bearing rats. The gluconeogenic tricarboxylic acid (TCA) cycle and respiratory chain enzyme activities significantly decreased in breast cancer-bearing rats. In addition, proliferating cell nuclear antigen (PCNA) was highly expressed in breast cancer tissues. However, the activities of glycolytic enzymes were significantly normalized in the tangeretin pre- and post-treated rats and the TCA cycle and respiratory chain enzyme activities were significantly increased in tangeretin treated rats. Furthermore, tangeretin down-regulated PCNA expression on breast cancer-bearing rats. Our study demonstrates that tangeretin specifically regulates cellular metabolic energy fluxes in DMBA-induced breast cancer-bearing rats.

  6. Facile synthesis and theoretical conformation analysis of a triazine-based double-decker rotor molecule with three anthracene blades.

    PubMed

    Kory, Max J; Bergeler, Maike; Reiher, Markus; Schlüter, A Dieter

    2014-06-01

    The facile synthesis of a rotor-shaped compound with two stacked triazine units, which are symmetrically connected by three anthracene blades through oxygen linkers, is presented. This new double-decker, which is a potential monomer for two-dimensional polymerization, was synthesized by using readily available, cheap building blocks, exploiting the known selectivity difference for the nucleophilic substitution of cyanuric chloride. The crystal structure of a C3h symmetric rotor-shaped compound with 9,10-dihydroanthracene blades, which is a direct precursor to the targeted monomer, and the crystal structure of the new double-decker with the desired C3h symmetry, are also reported. The synthetic efforts were preceded by a computational analysis, which was triggered by the question of conformational stability of the potential monomer. Two stable conformers could be found, and the barrier for the transition path in the gas phase between these conformers was determined by quantum chemical calculations. Exploratory Born-Oppenheimer molecular-dynamics simulations revealed a strong influence of solvent-solute interactions on the stability of the conformers, which resulted in an energetic preference of the C3h symmetric conformation of the double-decker. PMID:24737578

  7. Monolayers and Langmuir-Blodgett films of luminescent 1,3,5-triazine derivatives containing naphthalene or anthracene chromophores

    NASA Astrophysics Data System (ADS)

    Cai, Ya-Qi; Wu, Wei; Wang, Hua; Miyake, Jun; Qian, Dong-Jin

    2011-02-01

    Monolayer behaviors and Langmuir-Blodgett (LB) films of three luminescent aryl triazines, 2,4,6-tri(naphthalen-1-yl)-1,3,5-triazine (TN 1Ta), 2,4,6-tri(naphthalen-2-yl)-1,3,5-triazine (TN 2Ta), and 2,4,6-tri(anthracen-9-yl)-1,3,5-triazine (TATa) have been investigated. Surface pressure-area isotherms indicated that pure aryl triazines were difficult to form stable monolayers, while their mixtures with arachidic acid (AA) could be stabilized at the air-water interface. The mixed LB films of triazine-AA were deposited on substrate surfaces and analyzed by using UV-vis and infrared absorption spectra, X-ray photoelectron spectra, as well as scanning electron microscopy. Morphologies of the LB films and molecular aggregates were closely dependent on the structure of triazines and the surface pressures of deposition. Under UV radiation, TN 1Ta and TN 2Ta emitted at 410-460 nm while TATa emitted at 500-510 nm, with the emission lifetime falling into the range of 0.29 to 10.8 ns. Compared with those in solutions, the emissions of aryl triazines were red shifted in the LB films, especially for the TN 1Ta-AA and TN 2Ta-AA, which was attributed to the closely packed arrangement for the molecules in the LB films.

  8. 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.

  9. Tomato and garlic by gavage modulate 7,12-dimethylbenz[a]anthracene-induced genotoxicity and oxidative stress in mice.

    PubMed

    Bhuvaneswari, V; Velmurugan, B; Abraham, S K; Nagini, S

    2004-07-01

    Chemoprotection by dietary agents is a promising strategy for cancer prevention. The aim of the present study was to evaluate the combined effect of tomato and garlic against 7,12-dimethylbenz-[a]anthracene (DMBA)-induced genetic damage and oxidative stress in 12-14-week-old male Swiss albino mice. The animals were randomized into experimental and control groups and divided into eight groups of five animals each. Group 1 animals were injected intraperitoneally with 35 mg/kg body weight DMBA suspended in peanut oil as a single dose. Groups 2-4 animals received tomato (500 mg/kg body weight), garlic (125 mg/kg body weight) and a combination of tomato and garlic for 5 days by gavage, respectively, followed by DMBA 1.5 h after the final feeding. The doses of tomato and garlic correspond to the average human daily consumption. Animals in groups 5, 6 and 7 received tomato alone, garlic alone and tomato + garlic combination, respectively, for 5 days. Group 8 animals received the same volume of water and served as control. The incidence of bone marrow micronuclei and the extent of lipid peroxidation and the concentrations of antioxidants glutathione, glutathione peroxidase and glutathione-S-transferase were measured in the liver, 48 h after DMBA exposure. Increased frequency of micronuclei and enhanced lipid peroxidation accompanied by compromised antioxidant defenses were observed in DMBA-treated animals. Although pretreatment with tomato or garlic significantly reduced the frequency of DMBA-induced bone marrow micronuclei, the combination of tomato and garlic exhibited more profound effect in inhibiting DMBA-induced genotoxicity and oxidative stress. We suggest that a broad spectrum of antimutagenic and anticlastogenic effects can be achieved through an effective combination of functional foods such as tomato and garlic. PMID:15264010

  10. Dose-response effect of tomato paste on 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis.

    PubMed

    Bhuvaneswari, V; Velmurugan, B; Nagini, S

    2004-06-01

    We evaluated the dose-response effect of tomato paste on 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis using lipid peroxidation, reduced glutathione (GSH) and the GSH-dependent enzymes; glutathione peroxidase (GPx), glutathione-S-transferase (GST) and gamma-glutamyltranspeptidase (GGT) as biomarkers of chemoprevention. Hamsters were divided into eight groups of six animals each. The right buccal pouches of animals in group 1 were painted with a 0.5 per cent DMBA in liquid paraffin three times per week. Animals in groups 2 to 4 painted with DMBA as in group 1, received in addition, intragastric administration of tomato paste containing lycopene at concentrations of 2.5, 5 and 10 mgkg(-1)bw, respectively three times per week on days alternate to DMBA application. Groups 5 through 7 were given tomato paste alone. Animals in group 8 served as controls. All animals were killed after an experimental period of 14 weeks. Lipid peroxidation and GSH-dependent antioxidants were measured in the buccal pouch, liver and erythrocytes. Diminished lipid peroxidation in the HBP tumours was associated with enhanced levels of GSH and GSH-dependent enzymes. In contrast to the buccal pouch, the liver and erythrocytes of tumour-bearing hamsters exhibited elevated lipid peroxidation accompanied by compromised antioxidant status. Administration of tomato paste significantly reduced the incidence of HBP tumours, modulated lipid peroxidation and enhanced GSH and GSH-dependent enzymes in the pouch, liver and erythrocytes. Among the three doses used, tomato paste containing 5 mgkg(-1)bw lycopene showed the optimum effect. It is suggested that tomato paste exerts its chemopreventive effects by modulating lipid peroxidation and enhancing antioxidants in the target organ as well as in the liver and erythrocytes. PMID:15354408

  11. 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

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

    PubMed Central

    Ganesan, Shanthi; Keating, Aileen F.

    2014-01-01

    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. PMID:24269759

  13. Trianthema portulacastrum Linn. exerts chemoprevention of 7,12-dimethylbenz(a)anthracene-induced mammary tumorigenesis in rats.

    PubMed

    Bishayee, Anupam; Mandal, Animesh

    2014-10-01

    Due to limited treatment options for advanced-stage metastatic breast cancer, a high priority should be given to develop non-toxic chemopreventive drugs. The value of various natural and dietary agents to reduce the risk of developing breast cancer is well established. Trianthema portulacastrum Linn. (Aizoaceae), a dietary and medicinal plant, has been found to exert antihepatotoxic and antihepatocarcinogenic properties in rodents. This study was initiated to investigate mechanism-based chemopreventive potential of an ethanolic extract of T. portulacastrum (TPE) against 7,12-dimethylbenz(a)anthracene (DMBA)-initiated rat mammary gland carcinogenesis, an experimental tumor model that closely resembles human breast cancer. Rats had access to a basal diet supplemented with TPE to yield three dietary doses of the extract, i.e., 50, 100 and 200 mg/kg body weight. Following two weeks of TPE treatment, mammary tumorigenesis was initiated by oral administration of DMBA (50 mg/kg body weight). At the end of the study (16 weeks after DMBA exposure), TPE exhibited a striking reduction of DMBA-induced mammary tumor incidence, total tumor burden and average tumor weight and reversed intratumor histopathological alterations. TPE dose-dependently suppressed proliferating cell nuclear antigen and cyclin D1 expression, induced apoptosis, upregulated proapoptotic protein Bax, downregulated antiapoptotic protein Bcl-2 and diminished the expression of nuclear and cytosolic β-catenin in mammary tumors. Our results clearly provide the first experimental evidence that TPE exerts chemopreventive effect in the classical DMBA model of breast cancer by suppressing abnormal cell proliferation and inducing apoptosis mediated through alteration of Bax/Bcl-2 ratio. Mechanistically, TPE is capable of diminishing activated canonical Wnt/β-catenin signaling to exhibit antiproliferative, proapoptotic and oncostatic effects during an early-stage breast cancer. These results may encourage further

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. 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.

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

    PubMed Central

    Bhattacharya, Poulomi; Keating, Aileen F.

    2012-01-01

    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. PMID:22406437

  20. 7,12-Dimethylbenz[a]anthracene exposure induces the DNA repair response in neonatal rat ovaries

    PubMed Central

    Ganesan, Shanthi; Bhattacharya, Poulomi; Keating, Aileen F.

    2013-01-01

    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 nMd4; 12.5 nMd8), 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. PMID:23969067

  1. 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.

  2. 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

  3. 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

  4. (E)-1-(Anthracen-9-yl)-3-(2-chloro-6-fluoro­phen­yl)prop-2-en-1-one: crystal structure and Hirshfeld surface analysis

    PubMed Central

    Abdullah, Amzar Ahlami; Hassan, Nur Hafiq Hanif; Arshad, Suhana; Khalib, Nuridayanti Che; Razak, Ibrahim Abdul

    2016-01-01

    In the title compound, C23H14ClFO, the enone moiety adopts an E conformation. The dihedral angle between the benzene and anthracene ring is 63.42 (8)° and an intra­molecular C—H⋯F hydrogen bond generates an S(6) ring motif. In the crystal, mol­ecules are arranged into centrosymmetric dimers via pairs of C—H⋯F hydrogen bonds. The crystal structure also features C—H⋯π and π–π inter­actions. Hirshfeld surface analysis was used to confirm the existence of inter­molecular inter­actions. PMID:27308010

  5. 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

  6. 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.

  7. 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.

  8. 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.

  9. 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.

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

    PubMed

    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