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1

Benzaldehyde Thiosemicarbazone Derived from Limonene Complexed with Copper Induced Mitochondrial Dysfunction in Leishmania amazonensis  

PubMed Central

Background Leishmaniasis is a major health problem that affects more than 12 million people. Treatment presents several problems, including high toxicity and many adverse effects, leading to the discontinuation of treatment and emergence of resistant strains. Methodology/Principal Findings We evaluated the in vitro antileishmanial activity of benzaldehyde thiosemicarbazone derived from limonene complexed with copper, termed BenzCo, against Leishmania amazonensis. BenzCo inhibited the growth of the promastigote and axenic amastigote forms, with IC50 concentrations of 3.8 and 9.5 µM, respectively, with 72 h of incubation. Intracellular amastigotes were inhibited by the compound, with an IC50 of 10.7 µM. BenzCo altered the shape, size, and ultrastructure of the parasites. Mitochondrial membrane depolarization was observed in protozoa treated with BenzCo but caused no alterations in the plasma membrane. Additionally, BenzCo induced lipoperoxidation and the production of mitochondrial superoxide anion radicals in promastigotes and axenic amastigotes of Leishmania amazonensis. Conclusion/Significance Our studies indicated that the antileishmania activity of BenzCo might be associated with mitochondrial dysfunction and oxidative damage, leading to parasite death. PMID:22870222

Britta, Elizandra Aparecida; Barbosa Silva, Ana Paula; Ueda-Nakamura, Tânia; Dias-Filho, Benedito Prado; Silva, Cleuza Conceição; Sernaglia, Rosana Lázara; Nakamura, Celso Vataru

2012-01-01

2

Simultaneous Determination of Cobalt(II) and Nickel(II) by Fourth-Order Derivative Spectrophotometric Method Using 2-Hydroxy-3-Methoxy Benzaldehyde Thiosemicarbazone  

PubMed Central

A simple and new simultaneous fourth derivative spectrophotometric method is proposed for the analysis of a two-component system containing cobalt(II) and nickel(II) without separation using 2-hydroxy-3-methoxy benzaldehyde thiosemicarbazone (HMBATSC) as a chromophoric reagent. The reagent reacts with cobalt(II) and nickel(II) at pH 6.0, forming soluble brown and yellow colored species, respectively. Cobalt(II) and nickel(II) present in themixture are simultaneously determined without solving the simultaneous equations bymeasuring the fourth derivative amplitudes at 468.5 nm and 474.5 nm, respectively. The derivative amplitudes obey Beer's law at 468.5 nm and 474.5 nm for Co(II) and Ni(II) in the range 0.059–3.299 ?g mL?1 and 0.058–3.285 ?g mL?1 respectively. A large number of foreign ions do not interfere in the present method. The present simultaneous method is used for the determination of micro amounts of cobalt in biological samples, nickel in plant samples, and in some alloy steels and soil sample. PMID:17671609

Kumar, A. Praveen; Reddy, P. Raveendra; Reddy, V. Krishna

2007-01-01

3

Synthesis, Structure and Antioxidant Activity of (Tetra-O-acetyl-?-D-galactopyranosyl)thiosemicarbazones of Substituted Benzaldehydes  

PubMed Central

Some new substituted benzaldehyde (2,3,4,6-tetra-O-acetyl-?-D-galactopyranosyl) thiosemicarbazones were synthesised by reaction of 2,3,4,6-tetra-O-acetyl-?-D-galactopyranosyl thiosemicarbazide and different substituted benzaldehydes. The reaction was performed using conventional and microwave-assisted heating methods. The structures of thiosemicarbazones were confirmed by spectroscopic (IR, 1 H NMR, 13 C NMR and MS) method. The antioxidant activity of these thiosemicarbazones was evaluated, in vitro and in vivo, and it's shown that some of these compounds had significant antioxidant activity. PMID:23204623

Thanh, Nguyen D.; Hoai, Le T.

2012-01-01

4

Hydrogen bonds and antiviral activity of benzaldehyde derivatives  

NASA Astrophysics Data System (ADS)

We have obtained the Fourier transform IR spectra of solutions of benzaldehyde derivatives having different antiviral activities against a herpes virus. We observe a correlation between the presence of hydrogen bonds in the benzaldehyde molecules and the appearance of antiviral properties in the compounds. For compounds having antiviral activity, we have obtained spectral data suggesting the existence of hydrogen bonds of the type C=O???H-O and O-H???O in the molecules. When the hydrogen atom in the hydroxyl groups are replaced by a methyl group, no intramolecular hydrogen bonds are formed and the compounds lose their antiviral activity.

Tolstorozhev, G. B.; Skornyakov, I. V.; Belkov, M. V.; Shadyro, O. I.; Brinkevich, S. D.; Samovich, S. N.

2012-09-01

5

Structural studies and investigation on the activity of imidazole-derived thiosemicarbazones and hydrazones against crop-related fungi.  

PubMed

New imidazole derived thiosemicarbazones and hydrazones were prepared by condensation of 4(5)-imidazole carboxaldehyde, 4-(1H-imidazole-1-yl)benzaldehyde and 4-(1H-imidazole-1-yl)acetophenone with a thiosemicarbazide or hydrazide. All compounds were characterized by quantitative elemental analysis, IR and NMR techniques. Eight structures were determined by single crystal X-ray diffraction. The antifungal activities of the compounds were evaluated. None of the compounds exhibited significant activity against Aspergillus flavus and Candida albicans, while 4(5)-imidazolecarboxaldehyde thiosemicarbazone (ImT) and 4-(1H-imidazole-1-yl)benzaldehyde thiosemicabazone (4ImBzT) were highly and selectively active against Cladosporium cladosporioides. 4(5)-Imidazolecarboxaldehyde benzoyl hydrazone (4(5)ImPh), 4(5)-imidazolecarboxaldehyde-para-chlorobenzoyl hydrazone (4(5)ImpClPh), 4(5)-imidazolecarboxaldehyde-para-nitrobenzoyl hydrazone (4(5)ImpNO2Ph), 4-(imidazole-1-yl)acetophenone-para-chloro-benzoyl hydrazone (4ImAcpClPh) and 4-(imidazole-1-yl)acetophenone-para-nitro-benzoylhydrazone (4ImAcpNO2Ph) were highly active against Candida glabrata. 4(5)ImpClPh and 4(5)ImpNO2Ph were very effective against C. cladosporioides. In many cases, activity was superior to that of the reference compound nystatin. PMID:24129274

Reis, Débora C; Despaigne, Angel A Recio; Da Silva, Jeferson G; Silva, Nayane F; Vilela, Camila F; Mendes, Isolda C; Takahashi, Jacqueline A; Beraldo, Heloisa

2013-01-01

6

The antimicrobial activity of lapachol and its thiosemicarbazone and semicarbazone derivatives  

PubMed Central

Lapachol was chemically modified to obtain its thiosemicarbazone and semicarbazone derivatives. These compounds were tested for antimicrobial activity against several bacteria and fungi by the broth microdilution method. The thiosemicarbazone and semicarbazone derivatives of lapachol exhibited antimicrobial activity against the bacteria Enterococcus faecalis and Staphylococcus aureus with minimal inhibitory concentrations (MICs) of 0.05 and 0.10 µmol/mL, respectively. The thiosemicarbazone and semicarbazone derivatives were also active against the pathogenic yeast Cryptococcus gattii (MICs of 0.10 and 0.20 µmol/mL, respectively). In addition, the lapachol thiosemicarbazone derivative was active against 11 clinical isolates of Paracoccidioides brasiliensis, with MICs ranging from 0.01-0.10 µmol/mL. The lapachol-derived thiosemicarbazone was not cytotoxic to normal cells at the concentrations that were active against fungi and bacteria. We synthesised, for the first time, thiosemicarbazone and semicarbazone derivatives of lapachol. The MICs for the lapachol-derived thiosemicarbazone against S. aureus, E. faecalis, C. gattii and several isolates of P. brasiliensis indicated that this compound has the potential to be developed into novel drugs to treat infections caused these microbes. PMID:23778660

Souza, Marina Azevêdo; Johann, Susana; Lima, Luciana Alves Rodrigues dos Santos; Campos, Fernanda Fraga; Mendes, Isolda Castro; Beraldo, Heloisa; de Souza-Fagundes, Elaine Maria; Cisalpino, Patrícia Silva; Rosa, Carlos Augusto; Alves, Tânia Maria de Almeida; de Sá, Nívea Pereira; Zani, Carlos Leomar

2013-01-01

7

DNA binding, DNA cleavage, antioxidant and cytotoxicity studies on ruthenium(II) complexes of benzaldehyde 4-methyl-3-thiosemicarbazones.  

PubMed

Four new ruthenium(II) complexes with N(4)-methyl thiosemicarbazone ligands, (E)-2-(2-chlorobenzylidene)-N-methylhydrazinecarbothioamide (HL(1)) and (E)-N-methyl-2-(2-nitrobenzylidene)hydrazinecarbothioamide (HL(2)), were prepared and fully characterized by various spectro-analytical techniques. The Schiff bases act as bidentate, monobasic chelating ligands with S and N as the donor sites and are preferably found in the thiol form in all the complexes studied. The molecular structure of HL(1) and HL(2) were determined by single crystal X-ray diffraction method. DNA binding of the compounds was investigated by absorption spectroscopy which indicated that the complexes bind to DNA via intercalation. The oxidative cleavage of the complexes with CT-DNA inferred that the effects of cleavage are dose dependent. Antioxidant studies of the ligands and complexes showed the significant antioxidant activity against DPPH radical. In addition, the in vitro cytotoxicity of the ligands and complexes against MCF-7 cell line was assayed which showed higher cytotoxic activity with the lower IC(50) values indicating their efficiency in killing the cancer cells even at low concentrations. PMID:23376221

Sampath, Krishnan; Sathiyaraj, Subbaiyan; Jayabalakrishnan, Chinnasamy

2013-03-15

8

DNA binding, DNA cleavage, antioxidant and cytotoxicity studies on ruthenium(II) complexes of benzaldehyde 4-methyl-3-thiosemicarbazones  

NASA Astrophysics Data System (ADS)

Four new ruthenium(II) complexes with N(4)-methyl thiosemicarbazone ligands, (E)-2-(2-chlorobenzylidene)-N-methylhydrazinecarbothioamide (HL1) and (E)-N-methyl-2-(2-nitrobenzylidene)hydrazinecarbothioamide (HL2), were prepared and fully characterized by various spectro-analytical techniques. The Schiff bases act as bidentate, monobasic chelating ligands with S and N as the donor sites and are preferably found in the thiol form in all the complexes studied. The molecular structure of HL1 and HL2 were determined by single crystal X-ray diffraction method. DNA binding of the compounds was investigated by absorption spectroscopy which indicated that the complexes bind to DNA via intercalation. The oxidative cleavage of the complexes with CT-DNA inferred that the effects of cleavage are dose dependent. Antioxidant studies of the ligands and complexes showed the significant antioxidant activity against DPPH radical. In addition, the in vitro cytotoxicity of the ligands and complexes against MCF-7 cell line was assayed which showed higher cytotoxic activity with the lower IC50 values indicating their efficiency in killing the cancer cells even at low concentrations.

Sampath, Krishnan; Sathiyaraj, Subbaiyan; Jayabalakrishnan, Chinnasamy

2013-03-01

9

5-nitroisatin-derived thiosemicarbazones: potential antileishmanial agents.  

PubMed

A series of 29 previously reported N(4)-substituted 5-nitroisatin-3-thiosemicarbazones 2-30 has been screened for leishmanicidal potential. Compounds 2-4, 7, 8, 10-13, 15-19, 21, 23, 24, 26, 28 and 30 exhibited good to excellent antileishmanial activities with IC50 values ranging from 0.44?±?0.02 to 32.38?±?0.66?µg/mL. Of these, 5, 7, 19 and 28 proved to be the most active antileishmanial agents, displaying activities with IC50 values 1.78?±?0.35, 0.44?±?0.02, 1.91?±?0.04 and 4.28?±?0.75?µg/mL, respectively, which were even better than the standard drug, pentamidine (IC50?=?5.09?±?0.04?µg/mL). This study presents the first example of exhibition of leishmanicidal potential by isatin-thiosemicarbazones and as such furnishes a solid basis for further research on these compounds to develop more potent antileishmanial agents. PMID:24090424

Pervez, Humayun; Manzoor, Nazia; Yaqub, Muhammad; Khan, Khalid Mohammed

2014-10-01

10

Synthesis, molecular modeling, and biological evaluation of novel chiral thiosemicarbazone derivatives as potent anticancer agents.  

PubMed

A series of new chiral thiosemicarbazones derived from homochiral amines in both enantiomeric forms were synthesized and evaluated for their in vitro antiproliferative activity against A549 (human alveolar adenocarcinoma), MCF-7 (human breast adenocarcinoma), HeLa (human cervical adenocarcinoma), and HGC-27 (human stomach carcinoma) cell lines. Some of compounds showed inhibitory activities on the growth of cancer cell lines. Especially, compound exhibited the most potent activity (IC50 4.6??M) against HGC-27 as compared with the reference compound, sindaxel (IC50 10.3??M), and could be used as a lead compound to search new chiral thiosemicarbazone derivatives as antiproliferative agents. Chirality 27:177-188, 2015. © 2014 Wiley Periodicals, Inc. PMID:25399965

Ta?demir, Demet; Karaküçük-?yido?an, Ay?egül; Ula?li, Mustafa; Ta?kin-Tok, Tu?ba; Oruç-Emre, Em?ne Elç?n; Bayram, Hasan

2015-02-01

11

Electron-topological investigation of the structure-antitumor activity relationship of thiosemicarbazone derivatives.  

PubMed

In the frameworks of the electron-topological method (ETM) the structure-antitumor activity relationship was investigated for a series of thiosemicarbazone derivatives. The series included 70 compounds. Conformational analysis and quantum-chemical calculations were carried out for each compound. The revealed activity feature showed a satisfactory description of the class of active compounds according to two different parameters P and alpha estimating the probabilities of the feature realization in the class of active compounds (they are equal to 0.94 and 0.86, correspondingly). The results of testing demonstrated the high ability of ETM in predicting the activity investigated. PMID:9150865

Dimoglo, A S; Chumakov, Y M; Dobrova, B N; Saracoglu, M

1997-04-01

12

Metal derivatives of thiosemicarbazones: crystal structure of [chloro bis(triphenylphosphino) (thiophene-2-carbaldehyde thiosemicarbazone) copper(I)] complex  

Microsoft Academic Search

Reactions of copper(I) halides (X = Cl, Br, I) with thiophene-2-carbaldehyde thiosemicarbazone and triphenylphosphine in 1 : 1 : 2 molar ratio yield tetrahedral mononuclear complexes, [CuX(?-S-Httsc)(Ph3P)2] (X = Cl, 1; Br, 2; I, 3), characterized by elemental analysis, IR, NMR (H, C, P), and single crystal X-ray crystallography (1). The unit cell of 1 has two independent distorted tetrahedral

Tarlok S. Lobana; Rekha Sharma; Roohi Sharma

2009-01-01

13

Evaluation of DNA-binding, DNA cleavage, antioxidant and cytotoxic activity of mononuclear ruthenium(II) carbonyl complexes of benzaldehyde 4-phenyl-3-thiosemicarbazones.  

PubMed

Two 4-phenyl-3-thiosemicarbazone ligands, (E)-2-(2-chlorobenzylidene)-N-phenylhydrazinecarbothioamide (HL(1)) and (E)-2-(2-nitrobenzylidene)-N-phenylhydrazinecarbothioamide (HL(2)), and its ruthenium(II) complexes were synthesized and characterized by physico-chemical and spectroscopic methods. The Schiff bases act as bidentate, monobasic chelating ligands with S and N as the donor sites and are preferably found in the thiol form in all the complexes studied. The molecular structure of HL(1) and HL(2) were determined by single crystal X-ray diffraction method. DNA binding of the compounds was investigated by absorption spectroscopy which indicated that the compounds bind to DNA via intercalation. The oxidative cleavage of the complexes with CT-DNA inferred that the effects of cleavage are dose dependent. Antioxidant study of the ligands and complexes showed significant antioxidant activity against DPPH radical. In addition, the in vitro cytotoxicity of the ligands and complexes assayed against HeLa and MCF-7 cell lines showed higher cytotoxic activity with the lower IC50 values indicating their efficiency in killing the cancer cells even at low concentrations. PMID:23845986

Sampath, Krishnan; Sathiyaraj, Subbaiyan; Jayabalakrishnan, Chinnasamy

2013-11-01

14

Mixed ligand ruthenium(III) complexes of benzaldehyde 4-methyl-3-thiosemicarbazones with triphenylphosphine/triphenylarsine co-ligands: Synthesis, DNA binding, DNA cleavage, antioxidative and cytotoxic activity  

NASA Astrophysics Data System (ADS)

The new ruthenium(III) complexes with 4-methyl-3-thiosemicarbazone ligands, (E)-2-(2-chlorobenzylidene)-N-methylhydrazinecarbothioamide (HL1) and (E)-2-(2-nitrobenzylidene)-N-methylhydrazinecarbothioamide (HL2), were prepared and characterized by various physico-chemical and spectroscopic methods. The title compounds act as bidentate, monobasic chelating ligands with S and N as the donor sites and are preferably found in the thiol form in all the complexes studied. The molecular structure of HL1 and HL2 were determined by single crystal X-ray diffraction method. DNA binding of the ligands and complexes were investigated by absorption spectroscopy and IR spectroscopy. It reveals that the compounds bind to nitrogenous bases of DNA via intercalation. The oxidative cleavage of the complexes with CT-DNA inferred that the effects of cleavage are dose dependent. Antioxidant study of the ligands and complexes showed the significant antioxidant activity against DPPH radical. In addition, the in vitro cytotoxicity of the ligands and complexes against MCF-7 cell line was assayed which showed higher cytotoxic activity with the lower IC50 values indicating their efficiency in killing the cancer cells even at low concentrations.

Sampath, K.; Sathiyaraj, S.; Raja, G.; Jayabalakrishnan, C.

2013-08-01

15

Synthesis of isatin thiosemicarbazones derivatives: in vitro anti-cancer, DNA binding and cleavage activities.  

PubMed

New derivatives of thiosemicarbazone Schiff base with isatin moiety were synthesized L1-L6. The structures of these compounds were characterized based on the spectroscopic techniques. Compound L6 was further characterized by XRD single crystal. The interaction of these compounds with calf thymus (CT-DNA) exhibited high intrinsic binding constant (k(b)=5.03-33.00×10(5) M(-1)) for L1-L3 and L5 and (6.14-9.47×10(4) M(-1)) for L4 and L6 which reflect intercalative activity of these compounds toward CT-DNA. This result was also confirmed by the viscosity data. The electrophoresis studies reveal the higher cleavage activity of L1-L3 than L4-L6. The in vitro anti-proliferative activity of these compounds against human colon cancer cell line (HCT 116) revealed that the synthesized compounds (L3, L6 and L2) exhibited good anticancer potency. PMID:24607427

Ali, Amna Qasem; Teoh, Siang Guan; Salhin, Abdussalam; Eltayeb, Naser Eltaher; Khadeer Ahamed, Mohamed B; Abdul Majid, A M S

2014-05-01

16

Synthesis of isatin thiosemicarbazones derivatives: In vitro anti-cancer, DNA binding and cleavage activities  

NASA Astrophysics Data System (ADS)

New derivatives of thiosemicarbazone Schiff base with isatin moiety were synthesized L1-L6. The structures of these compounds were characterized based on the spectroscopic techniques. Compound L6 was further characterized by XRD single crystal. The interaction of these compounds with calf thymus (CT-DNA) exhibited high intrinsic binding constant (kb = 5.03-33.00 × 105 M-1) for L1-L3 and L5 and (6.14-9.47 × 104 M-1) for L4 and L6 which reflect intercalative activity of these compounds toward CT-DNA. This result was also confirmed by the viscosity data. The electrophoresis studies reveal the higher cleavage activity of L1-L3 than L4-L6. The in vitro anti-proliferative activity of these compounds against human colon cancer cell line (HCT 116) revealed that the synthesized compounds (L3, L6 and L2) exhibited good anticancer potency.

Ali, Amna Qasem; Teoh, Siang Guan; Salhin, Abdussalam; Eltayeb, Naser Eltaher; Khadeer Ahamed, Mohamed B.; Majid, A. M. S. Abdul

17

Gold-catalyzed annulations of 2-alkynyl benzaldehydes with vinyl ethers: synthesis of dihydronaphthalene, isochromene, and bicyclo[2.2.2]octane derivatives.  

PubMed

With the suitable selection of a gold catalyst as well as the appropriate control of the reaction conditions, various new gold-catalyzed cyclizations of 2-alkynyl benzaldehyde with acyclic or cyclic vinyl ethers have been developed. Acetal-tethered dihydronaphthalene and isochromenes were obtained from the reactions of 2-alkynyl benzaldehydes with acyclic vinyl ethers under mild conditions. And, more interestingly, the gold-catalyzed reactions of 2-alkynyl benzaldehyde with a cyclic vinyl ether afforded the bicyclo[2.2.2]octane derivative involving two molecules of cyclic vinyl ethers. These products contain interesting substructures that have been found in many biologically active molecules and natural products. In addition, a gold-catalyzed homo-dimerization of 2-phenylethynyl benzaldehyde 1a was observed when the reaction was carried out in the absence of vinyl ether, affording a set of separable diastereomeric products. Plausible mechanisms for these transformations are discussed; a gold-containing benzopyrylium was regarded as the crucial intermediate by which a number of these new transformations took place. PMID:23362089

Malhotra, Deepika; Liu, Le-Ping; Mashuta, Mark S; Hammond, G B

2013-03-18

18

Pestalols A-E, new alkenyl phenol and benzaldehyde derivatives from endophytic fungus Pestalotiopsis sp. AcBC2 isolated from the Chinese mangrove plant Aegiceras corniculatum.  

PubMed

Five alkenyl phenol and benzaldehyde derivatives, pestalols A-E (1-5), as well as seven known compounds (6-12), were isolated from endophytic fungus Pestalotiopsis sp. AcBC2 derived from the Chinese mangrove plant Aegiceras corniculatum. Their structures were determined by spectroscopic analyses. Compounds 2 and 3 showed cytotoxicity against a panel of 10 tumor cell lines. Compounds 1-5, 8, 9, 11, and 12 showed inhibitory activities against Influenza A virus subtype (H3N2) and Swine Flu (H1N1) viruses. Compound 2 also showed inhibitory activity against tuberculosis. PMID:24690916

Sun, Jian-Fan; Lin, Xiuping; Zhou, Xue-Feng; Wan, Junting; Zhang, Tianyu; Yang, Bin; Yang, Xian-Wen; Tu, Zhengchao; Liu, Yonghong

2014-06-01

19

Antioxidant, antimicrobial, and theoretical studies of the thiosemicarbazone derivative Schiff base 2-(2-imino-1-methylimidazolidin-4-ylidene)hydrazinecarbothioamide (IMHC)  

PubMed Central

Background Adverse antimicrobial activities of thiosemicarbazone (TSC) and Schiff base derivatives have widely been studied by using different kinds of microbes, in addition different methods were used to assay the antioxidant activities using DPPH, peroxids, or ntrosyl methods. However, there are no studies describing the synthesis of TSC derived from creatinine. Results In this study, 2-(2-imino-1-methylimidazolidin-4-ylidene)hydrazinecarbothioamide (IMHC) was synthesized by the reaction of creatinine with thiosemicarbazide. The novel molecule was characterized by FT-IR, UV-VIS, and NMR spectra in addition of the elemental analysis. The free radical scavenging ability of the IMHC was determined by it interaction with the stable-free radical 2,2"-diphenyl-1-picrylhydrazyl (or nitric oxide or hydrogen peroxide) and showed encouraging antioxidant activities. Density functional theory calculations of the IMHC performed using molecular structures with optimized geometries. Molecular orbital calculations provide a detailed description of the orbitals, including spatial characteristics, nodal patterns, and the contributions of individual atoms. Highest occupied molecular orbital-lowest unoccupied molecular orbital energies and structures are shown. Conclusions IMHC shows considerable antibacterial and antifungal activities. The free radical scavenging activity of synthesized compound was screened for in vitro antioxidant activity. PMID:22373542

2012-01-01

20

Spectral and structural studies of copper(II) complexes of thiosemicarbazones derived from salicylaldehyde and containing ring incorporated at N(4)-position  

NASA Astrophysics Data System (ADS)

Mononuclear and binuclear copper(II) complexes ( 1- 8) with two ONS donor thiosemicarbazone ligands {salicylaldehyde 3-hexamethyleneiminyl thiosemicarbazone [H 2L 1] and salicylaldehyde 3-tetramethyleneiminyl thiosemicarbazone [H 2L 2]} have been prepared and physico-chemically characterized. IR, electronic and EPR spectra of the complexes have been obtained. The thiosemicarbazones bind to metal as dianionic ONS donor ligands in all the complexes except in [Cu(HL 1) 2] ( 2) and [Cu(HL 2) 2] ( 6). In compounds 2 and 6 the ligands are coordinated as monoanionic HL - ones. The magnetic susceptibility measurements indicate that all the complexes are paramagnetic. In complex [(CuL 1) 2] ( 1), the magnetic moment value is lower than the expected spin only value. In all the complexes g|| > g? > 2.0023 and G values within the range 2.5-3.5 are consistent with d ground state. The complexes were given the formula as [(CuL 1) 2] ( 1); [Cu(HL 1) 2] ( 2); [CuL 1bpy] ( 3); [CuL 1phen] ( 4); [CuL 1?-pic]·2H 2O ( 5); [Cu(HL 2) 2] ( 6); [CuL 2py]·3H 2O ( 7); [CuL 2bipy] ( 8). The structure of the compound 8 have been solved by single crystal X-ray crystallography and was found to be distorted square pyramid around copper(II) ion.

Latheef, Leji; Kurup, Maliyeckal R. Prathapachandra

2008-06-01

21

Spectrophotometric, voltammetric and cytotoxicity studies of 2-hydroxy-5-methoxyacetophenone thiosemicarbazone and its N(4)-substituted derivatives: A combined experimental-computational study  

NASA Astrophysics Data System (ADS)

In this study, 2-hydroxy-5-methoxyacetophenone thiosemicarbazone (HMAT) and its novel N(4) substituted derivatives were synthesized and characterized by different techniques. The optical band gap of the compounds and the energy of HOMO were experimentally examined by UV-vis spectra and cyclic voltammetry measurements, respectively. Furthermore, the conformational spaces of the compounds were scanned with molecular mechanics method. The geometry optimization, HOMO and LUMO energies, the energy gap of the HOMO-LUMO, dipole moment of the compounds were theoretically calculated by the density functional theory B3LYP/6-311++G(d,p) level. The minimal electronic excitation energy and maximum wavelength calculations of the compounds were also performed by TD-DFT//B3LYP/6-311++G(d,p) level of theory. Theoretically calculated values were compared with the related experimental values. The combined results exhibit that all compounds have good electron-donor properties which affect anti-proliferative activity. The cytotoxic effects of the compounds were also evaluated against HeLa (cervical carcinoma), MCF-7 (breast carcinoma) and PC-3 (prostatic carcinoma) cell lines using the standard MTT assay. All tested compounds showed antiproliferative effect having IC50 values in different range. In comparison with that of HMAT, it was obtained that while ethyl group on 4(N)-substituted position decreased in potent anti-proliferative effect, the phenyl group on the position increased in anti-proliferative effect for the tested cancer cell line. Considering the molecular energy parameters, the cytotoxicity activities of the compounds were discussed.

Akgemci, Emine Guler; Saf, Ahmet Ozgur; Tasdemir, Halil Ugur; Türkkan, Ercan; Bingol, Haluk; Turan, Suna Ozbas; Akkiprik, Mustafa

2015-02-01

22

Synthesis, spectral and antimicrobial activity of Zn(II) complexes with Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and benzaldehyde/2-hydroxyacetophenone/indoline-2,3-dione.  

PubMed

Zn(II) complexes have been synthesized by reacting zinc acetate with Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and 2-hydroxyacetophenone/benzaldehyde/indoline-2,3-dione. All these complexes are soluble in DMF and DMSO; low molar conductance values indicate that they are non electrolytes. Elemental analyses suggest that the complexes have 1:2 metal to ligands stoichiometry of the types [ZnL2(H2O)2](L=monoanionic Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and 2-hydroxyacetophenone/indoline-2,3-dione) [ZnL2(')(OOCCH3)2(H2O)2](L'=neutral Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and benzaldehyde), and they were characterized by IR, (1)H NMR, and (13)C NMR. Particle sizes of synthesized compounds were measured with dynamic light scattering (DLS) analyser which indicates that particle diameter are of the range ca. 100-200nm. All these Schiff bases and their complexes have also been screened for their antibacterial (Bacillus subtilis (B. subtilis), Escherichia coli (E. coli) and antifungal activities (Colletotrichum falcatum (C. falcatum), Aspergillus niger (A. niger), Fusarium oxysporium (F. oxysporium) Curvularia pallescence (C. pallescence). The antimicrobial activities have shown that upon complexation the activity increases. PMID:23747379

Singh, Ajay K; Pandey, O P; Sengupta, S K

2013-09-01

23

Benzaldehyde-functionalized Polymer Vesicles  

PubMed Central

Polymer vesicles with diameters of ca. 100-600 nm and bearing benzaldehyde functionalities within the vesicular walls were constructed through self assembly of an amphiphilic block copolymer PEO45-b-PVBA26 in water. The reactivity of the benzaldehyde functionalities was verified by crosslinking the polymersomes, and also by a one-pot crosslinking and functionalization approach to further render the vesicles fluorescent, each via reductive amination. In vitro studies found these labelled nanostructures to undergo cell association. PMID:19309173

Sun, Guorong; Fang, Huafeng; Cheng, Chong; Lu, Peng; Zhang, Ke; Walker, Amy V.; Taylor, John-Stephen A.; Wooley, Karen L.

2009-01-01

24

Inhibitory Effects of Benzaldehyde Derivatives from the Marine Fungus Eurotium sp. SF-5989 on Inflammatory Mediators via the Induction of Heme Oxygenase-1 in Lipopolysaccharide-Stimulated RAW264.7 Macrophages  

PubMed Central

Two benzaldehyde derivatives, flavoglaucin (1) and isotetrahydro-auroglaucin (2), were isolated from the marine fungus Eurotium sp. SF-5989 through bioassay- and 1H NMR-guided investigation. In this study, we evaluated the anti-inflammatory effects of these compounds in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. We demonstrated that compounds 1 and 2 markedly inhibited LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production by suppressing inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression without affecting cell viability. We also demonstrated that the compounds reduced the secretion of pro-inflammatory cytokines such as tumor necrosis factor-? (TNF-?), interleukin-1? (IL-1?) and interleukin-6 (IL-6). Furthermore, compounds 1 and 2 inhibited LPS-induced nuclear factor-?B (NF-?B) activation by suppressing phosphorylation of IkappaB (I?B). These results indicated that the anti-inflammatory effects of these benzaldehyde derivatives in LPS-stimulated RAW264.7 macrophages were due to the inactivation of the NF-?B pathway. In addition, compounds 1 and 2 induced heme oxygenase-1 (HO-1) expression through the nuclear transcription factor-E2–related factor 2 (Nrf2) translocation. The inhibitory effects of compounds 1 and 2 on the production of pro-inflammatory mediators and on NF-?B binding activity were reversed by HO-1 inhibitor tin protoporphyrin (SnPP). Thus, the anti-inflammatory effects of compounds 1 and 2 also correlated with their ability of inducing HO-1 expression. PMID:25535073

Kim, Kyoung-Su; Cui, Xiang; Lee, Dong-Sung; Ko, Wonmin; Sohn, Jae Hak; Yim, Joung Han; An, Ren-Bo; Kim, Youn-Chul; Oh, Hyuncheol

2014-01-01

25

Inhibitory Effects of Benzaldehyde Derivatives from the Marine Fungus Eurotium sp. SF-5989 on Inflammatory Mediators via the Induction of Heme Oxygenase-1 in Lipopolysaccharide-Stimulated RAW264.7 Macrophages.  

PubMed

Two benzaldehyde derivatives, flavoglaucin (1) and isotetrahydro-auroglaucin (2), were isolated from the marine fungus Eurotium sp. SF-5989 through bioassay- and 1H NMR-guided investigation. In this study, we evaluated the anti-inflammatory effects of these compounds in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. We demonstrated that compounds 1 and 2 markedly inhibited LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production by suppressing inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression without affecting cell viability. We also demonstrated that the compounds reduced the secretion of pro-inflammatory cytokines such as tumor necrosis factor-? (TNF-?), interleukin-1? (IL-1?) and interleukin-6 (IL-6). Furthermore, compounds 1 and 2 inhibited LPS-induced nuclear factor-?B (NF-?B) activation by suppressing phosphorylation of IkappaB (I?B). These results indicated that the anti-inflammatory effects of these benzaldehyde derivatives in LPS-stimulated RAW264.7 macrophages were due to the inactivation of the NF-?B pathway. In addition, compounds 1 and 2 induced heme oxygenase-1 (HO-1) expression through the nuclear transcription factor-E2-related factor 2 (Nrf2) translocation. The inhibitory effects of compounds 1 and 2 on the production of pro-inflammatory mediators and on NF-?B binding activity were reversed by HO-1 inhibitor tin protoporphyrin (SnPP). Thus, the anti-inflammatory effects of compounds 1 and 2 also correlated with their ability of inducing HO-1 expression. PMID:25535073

Kim, Kyoung-Su; Cui, Xiang; Lee, Dong-Sung; Ko, Wonmin; Sohn, Jae Hak; Yim, Joung Han; An, Ren-Bo; Kim, Youn-Chul; Oh, Hyuncheol

2014-01-01

26

Impact of terminal dimethylation on the resistance profile of ?-N-heterocyclic thiosemicarbazones  

PubMed Central

Triapine is an ?-N-heterocyclic thiosemicarbazone with promising anticancer activity against hematologic malignancies but widely ineffective against solid tumor types in clinical trials. The anticancer activity of thiosemicarbazones can be dramatically increased by terminal dimethylation. KP1089 is a gallium compound containing two terminal dimethylated thiosemicarbazone ligands. To gain insights on the vulnerability of this highly active terminal dimethylated thiosemicarbazone to drug resistance mechanisms, a new cell model with acquired resistance against the lead compound KP1089 was established. Subsequent genomic analyses (arrayCGH and FISH) revealed amplification of the ABCC1 gene on double minute chromosomal DNA in KP1089-resistant cells as well as overexpression of ABCC1 and ABCG2 on the protein level. KP1089 was further confirmed as a substrate of ABCC1 and ABCG2 but not of ABCB1 using a panel of ABC transporter-overexpressing cell models as well as ABC transporter inhibitors. Moreover, glutathione depletion strongly enhanced KP1089 activity, although no glutathione conjugate formation by glutathione-S-transferase was observed. Thus, a co-transport of KP1089 together with glutathione is suggested. Finally, a panel of thiosemicarbazone derivatives was tested on the new KP1089-resistant cell line. Notably, KP1089-resistant cells were not cross-resistant against thiosemicarbazones lacking terminal dimethylation (e.g. Triapine) which are less active than KP1089. This suggests that terminal dimethylation of thiosemicarbazones – linked with distinctly enhanced anticancer activity – leads to altered resistance profiles compared to classical thiosemicarbazones making this compound class of interest for further (pre)clinical evaluation. PMID:22426010

Heffeter, Petra; Pirker, Christine; Kowol, Christian R.; Herrman, Gerrit; Dornetshuber, Rita; Miklos, Walter; Jungwirth, Ute; Koellensperger, Gunda; Keppler, Bernhard K.; Berger, Walter

2012-01-01

27

The Kinetic Behavior of Benzaldehyde under Hydrothermal Conditions  

NASA Astrophysics Data System (ADS)

Aldehydes represent an intermediate redox state between alcohols and carboxylic acids and are likely intermediates in the transformation of organic compounds in natural systems. We have conducted kinetic studies of a model aldehyde, benzaldehyde, in high-temperature water (250-350 °C, saturation pressure) in clear fused quartz (CFQ) autoclaves. Under these conditions, benzaldehyde is observed to undergo a disproportionation reaction to benzyl alcohol and benzoic acid reminiscent of the base-catalyzed Cannizzaro reaction known to occur at cooler temperatures. Benzene is also produced via decarbonylation of the aldehyde. We have obtained pseudo second-order rate constants for the decomposition of benzaldehyde at 250, 300, and 350 °C. Rates derived via repeated heating phases and subsequent quantitative 13C-NMR spectroscopy of a single NMR-compatible CFQ tube containing isotopically labeled benzaldehyde are consistent with those obtained by analysis of product suites from individual timed experiments via gas chromatography. Arrhenius parameters for these rate constants are consistent with published values for the reaction under supercritical conditions from one study (Tsao et al. 1992) yet the pre-exponential factor is approximately 7 orders of magnitude smaller than that derived from another study (Ikushima et al. 2001). Moreover, fitting our rate constants with the Eyring equation yields an entropy of activation (?S‡) of -26.6 kcal mol-1 K-1, which is consistent for a bimolecular transition state at the rate-limiting step. In contrast, the rates of Ikushima et al. yield a positive value of ?S‡, which is inconsistent with the putative mechanism for the reaction. The linear Arrhenius behavior of the decomposition of benzaldehyde from high-temperature liquid to supercritical conditions demonstrates the potential for extrapolating experimentally derived rates of reactions for organic functional group transformations to conditions where diagenesis, alteration, metamorphism, and other hydrothermal processes of interest occur in natural systems. References Ikushima, Y., K. Hatakeda, O. Sato, T. Yokoyama, and M. Arai. 2001. Structure and base catalysis of supercritical water in the noncatalytic benzaldehyde disproportionation using water at high temperatures and pressures. Angewandte Chemie, 40, 210-213. Tsao, C.C., Y. Zhou, X. Liu, and T.J. Houser. 1992. Reactions of supercritical water with benzaldehyde, benzylidenebenzylamine, benzyl alcohol, and benzoic acid. The Journal of Supercritical Fluids, 5, 107-113.

Fecteau, K.; Gould, I.; Hartnett, H. E.; Williams, L. B.; Shock, E.

2013-12-01

28

Stability of the Resistance to the Thiosemicarbazone Derived from 5,6-Dimethoxy-1-Indanone, a Non-Nucleoside Polymerase Inhibitor of Bovine Viral Diarrhea Virus  

PubMed Central

Bovine viral diarrhea virus (BVDV) is the prototype Pestivirus. BVDV infection is distributed worldwide and causes serious problems for the livestock industry. The thiosemicarbazone of 5,6-dimethoxy-1-indanone (TSC) is a non-nucleoside polymerase inhibitor (NNI) of BVDV. All TSC-resistant BVDV variants (BVDV-TSCr T1–5) present an N264D mutation in the NS5B gene (RdRp) whereas the variant BVDV-TSCr T1 also presents an NS5B A392E mutation. In the present study, we carried out twenty passages of BVDV-TSCr T1–5 in MDBK cells in the absence of TSC to evaluate the stability of the resistance. The viral populations obtained (BVDV R1–5) remained resistant to the antiviral compound and conserved the mutations in NS5B associated with this phenotype. Along the passages, BVDV R2, R3 and R5 presented a delay in the production of cytopathic effect that correlated with a decrease in cell apoptosis and intracellular accumulation of viral RNA. The complete genome sequences that encode for NS2 to NS5B, Npro and Erns were analyzed. Additional mutations were detected in the NS5B of BVDV R1, R3 and R4. In both BVDV R2 and R3, most of the mutations found were localized in NS5A, whereas in BVDV R5, the only mutation fixed was NS5A V177A. These results suggest that mutations in NS5A could alter BVDV cytopathogenicity. In conclusion, the stability of the resistance to TSC may be due to the fixation of different compensatory mutations in each BVDV-TSCr. During their replication in a TSC-free medium, some virus populations presented a kind of interaction with the host cell that resembled a persistent infection: decreased cytopathogenicity and viral genome synthesis. This is the first report on the stability of antiviral resistance and on the evolution of NNI-resistant BVDV variants. The results obtained for BVDV-TSCr could also be applied for other NNIs. PMID:24950191

Castro, Eliana F.; Campos, Rodolfo H.; Cavallaro, Lucía V.

2014-01-01

29

Evaluation of thiosemicarbazone derivative as chelating agent for the simultaneous removal and trace determination of Cd(II) and Pb(II) in food and water samples.  

PubMed

In the present investigation, prepared N-ethyl-3-carbazolecarbaxaldehyde-3-thiosemicarbazone (ECCT) and employed for the simultaneous removal and determination of trace amounts of Cd(II) and Pb(II) from food and water samples. Cd(II) and Pb(II) gave yellow and orange colored complexes with ECCT in acetate buffer at pH 6.0 with ?max, 380 and 440nm, respectively. Both complexes were easily extractable into kerosene at 1:1(M:L) composition. It was in accordance with Beer's law in the range of 0.0-12.0 and 0.0-10.0?gmL(-1) with 0.999 and 0.997 correlation coefficient for Cd(II) and Pb(II) complexes, respectively, indicated a good linearity between the two variables. The molar absorptivity and Sandell's sensitivity were found to be 0.740×10(4)Lmol(-1)cm(-1), 1.52×10(-3)?gcm(-2) for Cd(II) and 1.809×10(4)L mol(-1)cm(-1), 1.15×10(-3)?gcm(-2) for Pb(II). The precision and accuracy of the method was checked for both metal ions by finding the relative standard deviations (n=8), which were 0.689% and 0.443%, with detection limits of 0.00151?gL(-1) and 0.00264?gL(-1) for Cd(II) and Pb(II), respectively. Further validation using certified reference material, NIST 1568b, resulted in determined concentrations of 0.028±0.253?gg(-1) for Cd(II) and 0.046±0.325?gg(-1) for Pb(II). These determined values agree well with the certified values in the reference materials. The interfering effects of various cations and anions were also studied. The proposed method performance was also evaluated in terms of Student 'T' test and Variance 'F' test, which indicated the significance of the present method parameters, as an inter comparison of the experimental values using ICP-OES. PMID:24360411

Koduru, Janardhan Reddy; Lee, Kap Duk

2014-05-01

30

Synthesis and spectral characterization of mono- and binuclear copper(II) complexes derived from 2-benzoylpyridine-N(4)-methyl-3-thiosemicarbazone: Crystal structure of a novel sulfur bridged copper(II) box-dimer.  

PubMed

Mononuclear and binuclear copper(II) complexes of 2-benzoylpyridine-N(4)-methyl thiosemicarbazone (HL) were prepared and characterized by a variety of spectroscopic techniques. Structural evidence for the novel sulfur bridged copper(II) iodo binuclear complex is obtained by single crystal X-ray diffraction analysis. The complex [Cu2L2I2], a non-centrosymmetric box dimer, crystallizes in monoclinic C2/c space group and it was found to have distorted square pyramidal geometry (Addison parameter, ?=0.238) with the square basal plane occupied by the thiosemicarbazone moiety and iodine atom whereas the sulfur atom from the other coordinated thiosemicarbazone moiety occupies the apical position. This is the first crystallographically studied system having non-centrosymmetrical entities bridged via thiolate S atoms with Cu(II)I bond. The tridentate thiosemicarbazone coordinates in mono deprotonated thionic tautomeric form in all complexes except in sulfato complex, [Cu(HL)(SO4)]·H2O (1) where it binds to the metal centre in neutral form. The magnetic moment values and the EPR spectral studies reflect the binuclearity of some of the complexes. The spin Hamiltonian and bonding parameters are calculated based on EPR studies. In all the complexes g||>g?>2.0023 and the g values in frozen DMF are consistent with the [Formula: see text] ground state. The thermal stabilities of some of the complexes were also determined. PMID:25546494

Jayakumar, K; Sithambaresan, M; Aiswarya, N; Kurup, M R Prathapachandra

2015-03-15

31

Pentadentate thiosemicarbazones as versatile chelating systems. A comparative structural study of their metallic complexes.  

PubMed

We have prepared some transition and post-transition metal complexes derived from the pentadentate thiosemicarbazone ligand bis(4-N-ethylthiosemicarbazone)-2,6-diacetylpyridine H(2)L(Et), by both chemical and electrochemical procedures. The complexes have been synthesised and fully characterised, including the crystal structures for the ligand H(2)L(Et) and its manganese, cadmium and lead complexes. We have also performed multinuclear (109)Ag, (113)Cd, (119)Sn and (207)Pb studies for silver, cadmium, tin and lead compounds, respectively. Moreover we present here a comparative study on the different structures found for pentadentate thiosemicarbazonate complexes, trying to check the influence of different factors, such as experimental procedure, size of metal, structure of the ligand, and metal oxidation state, on the final structure of the complex formed. Our aim is gaining a better insight into the coordination trends of pentadentate thiosemicarbazone ligands. PMID:19153625

Pedrido, Rosa; González-Noya, Ana M; Romero, Maria J; Martínez-Calvo, Miguel; Vázquez López, Miguel; Gómez-Fórneas, Esther; Zaragoza, Guillermo; Bermejo, Manuel R

2008-12-21

32

Novel R-(+)-limonene-based thiosemicarbazones and their antitumor activity against human tumor cell lines.  

PubMed

In an attempt to develop potent and selective antitumor agents, a series of novel thiosemicarbazones derived from a natural monoterpene R-(+)-limonene was synthesized and their antitumor activity was evaluated. Overall, the majority of tested compounds exhibited considerable inhibitory effects on the growth of a wide range of cancer cell lines. Almost all of tested thiosemicarbazones were especially sensitive to prostate cells (PC-3). Derivatives 5, 6, 8, 9, 10, 11 and 13 presented the most potent antitumor activity against PC-3 cells. These compounds showed lower value of GI50 (0.04-0.05 ?M) than the reference drug paclitaxel, besides a high selectivity for the same cell line. The 4-fluorobenzaldehyde derivative 10 was the most selective compound for prostate cells, while 2-hydroxybenzaldehyde derivative 8 was the most active compound, with potent antitumor activity against all tested cell lines. PMID:24727464

Vandresen, Fábio; Falzirolli, Hugo; Almeida Batista, Sabrina A; da Silva-Giardini, Ana Paula B; de Oliveira, Diogo N; Catharino, Rodrigo R; Ruiz, Ana Lúcia T G; de Carvalho, João E; Foglio, Mary Ann; da Silva, Cleuza Conceição

2014-05-22

33

Gold catalyst Styrene Benzaldehyde Styrene oxide Acetophenone  

E-print Network

O O O + + O2 Gold catalyst Styrene Benzaldehyde Styrene oxide Acetophenone studies. However, the study by Turner et al.1 seems to be the first to use Au55 in the synthesis of supported gold catalysts attempts to relate structure to activity in gold catalysis. What, then, makes gold particles of this size

Rouyer, Francois

34

Oxidation of Benzaldehyde to Benzoic Acid  

Microsoft Academic Search

Benzaldehyde was oxidized to benzoic acid using Na2WO4·2H2O as a catalyst. Different factors, such as different acidic additives, the reaction time, the amount of catalyst, and hydrogen peroxide dosage, on the isolated yield of benzoic acid were investigated. The effects of surfactants on yield of benzoic acid were also discussed in the acid-free system. The results indicated that both acidic

Hongyan Yan; Chunsheng Liu; Genxiang Luo

2005-01-01

35

Benzaldehyde dehydrogenase from chitosan-treated Sorbus aucuparia cell cultures.  

PubMed

Cell cultures of Sorbus aucuparia respond to the addition of chitosan with the accumulation of the biphenyl phytoalexin aucuparin. The carbon skeleton of this inducible defense compound is formed by biphenyl synthase (BIS) from benzoyl-CoA and three molecules of malonyl-CoA. The formation of benzoyl-CoA proceeds via benzaldehyde as an intermediate. Benzaldehyde dehydrogenase (BD), which converts benzaldehyde into benzoic acid, was detected in cell-free extracts from S. aucuparia cell cultures. BD and BIS were induced by chitosan treatment. The preferred substrate for BD was benzaldehyde (K(m)=49 microM). Cinnamaldehyde and various hydroxybenzaldehydes were relatively poor substrates. BD activity was strictly dependent on the presence of NAD(+) as a cofactor (K(m)=67 microM). PMID:19409654

Gaid, Mariam M; Sircar, Debabrata; Beuerle, Till; Mitra, Adinpunya; Beerhues, Ludger

2009-09-01

36

Synthesis and characterization of new aromatic aldehyde/ketone 4-(beta-D-glucopyranosyl)thiosemicarbazones.  

PubMed

A series of 22 aromatic aldehyde/ketone 4-(beta-D-glucopyranosyl)thiosemicarbazones have been synthesized by condensation of 4-(per-O-acetylated-beta-D-glucopyranosyl)thiosemicarbazide with an aldehyde or a ketone, and then, deacetylation of the resulting product. The compounds were fully characterized by spectroscopic techniques, elemental analysis, and for two derivatives by X-ray analysis. The data indicate the beta configuration, and the E configuration pertaining to the stereochemistry of the C=N bond. However, a partial conversion of the E-form into the Z-form is possible in solution after several hours. PMID:19497560

Tenchiu Deleanu, Alia-Cristina; Kostas, Ioannis D; Kovala-Demertzi, Dimitra; Terzis, Aris

2009-07-27

37

A novel series of thiosemicarbazone drugs: From synthesis to structure  

NASA Astrophysics Data System (ADS)

A new series of thiosemicarbazones (TSCs) and their 1,3,4-thiadiazolines (TDZs) containing acetamide group have been synthesized from thiosemicarbazide compounds by the reaction of TSCs with cyclic ketones as well as aromatic aldehydes. The structures of newly synthesized 1,3,4-thiadiazole derivatives obtained by heterocyclization of the TSCs with acetic anhydride were experimentally characterized by spectral methods using IR, 1H NMR, 13C NMR and mass spectroscopic methods. Furthermore, the structural, thermodynamic, and electronic properties of the studied compounds were also studied theoretically by performing Density Functional Theory (DFT) to access reliable results to the experimental values. The molecular geometry, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) and Mulliken atomic charges of the studied compounds have been calculated at the B3LYP method and standard 6-31+G(d,p) basis set starting from optimized geometry. The theoretical 13C chemical shift results were also calculated using the gauge independent atomic orbital (GIAO) approach and their respective linear correlations were obtained.

Ebrahimi, Hossein Pasha; Hadi, Jabbar S.; Alsalim, Tahseen A.; Ghali, Thaer S.; Bolandnazar, Zeinab

2015-02-01

38

Adsorption, mobility, and dimerization of benzaldehyde on Pt(111).  

PubMed

Building on results for the adsorption of benzene on Pt(111), the adsorption of benzaldehyde is investigated using density functional theory. Benzaldehyde is found to chemisorb preferentially with its aromatic ring in the flat-lying bridge geometry that is also preferred for benzene. Across the investigated geometries, adsorption is homogeneously weakened compared to corresponding benzene geometries. This is found to be true for very different adsorption modes, namely, ?(6) and ?(8) modes, the latter having metal atoms inserted in the carbonyl bond. Reorientation and diffusion of benzaldehyde is found to have low energy barriers. Aggregation of molecules in dimers bound by aryl C-H···O hydrogen bonds is investigated, and specific configurations are found to be up to 0.15 eV more favorable than optimally configured, separated adsorbates. The binding is significantly stronger than what is found for gas phase dimers, suggesting an enhancing effect of the metal interaction. PMID:22583264

Rasmussen, Anton M H; Hammer, Bjørk

2012-05-01

39

Adsorption, mobility, and dimerization of benzaldehyde on Pt(111)  

NASA Astrophysics Data System (ADS)

Building on results for the adsorption of benzene on Pt(111), the adsorption of benzaldehyde is investigated using density functional theory. Benzaldehyde is found to chemisorb preferentially with its aromatic ring in the flat-lying bridge geometry that is also preferred for benzene. Across the investigated geometries, adsorption is homogeneously weakened compared to corresponding benzene geometries. This is found to be true for very different adsorption modes, namely, ?6 and ?8 modes, the latter having metal atoms inserted in the carbonyl bond. Reorientation and diffusion of benzaldehyde is found to have low energy barriers. Aggregation of molecules in dimers bound by aryl C-H⋯O hydrogen bonds is investigated, and specific configurations are found to be up to 0.15 eV more favorable than optimally configured, separated adsorbates. The binding is significantly stronger than what is found for gas phase dimers, suggesting an enhancing effect of the metal interaction.

Rasmussen, Anton M. H.; Hammer, Bjørk

2012-05-01

40

Lanthanum(III) and praseodymium(III) complexes with isatin thiosemicarbazones  

NASA Astrophysics Data System (ADS)

Ten new lanthanum(III) and praseodymium(III) complexes of the general formula Na[La(L) 2H 2O] (Ln = La(III) or Pr(III); LH 2 = thiosemicarbazones) derived from the condensation of isatin with 4-phenyl thiosemicarbazide, 4-(4-chlorophenyl) thiosemicarbazide, 4-(2-nitrophenyl) thiosemicarbazide, 4-(2-bromophenyl) thiosemicarbazide and 4-(2-methylphenyl) thiosemicarbazide, have been synthesized in methanol in presence of sodium hydroxide. The XRD spectra of the complexes were monitored to verify complex formation. The complexes have also been characterized by elemental analysis, molar conductance, electronic absorption and fluorescence, infrared, far infrared, 1H and 13C NMR spectral studies. Thermal studies of these complexes have been carried out in the temperature range 25-800 °C using TG, DTG and DTA techniques. All these complexes decompose gradually with the formation of Ln 2O 3 as the end product. The Judd-ofelt intensity parameter, oscillator strength, transition probability, stimulated emission cross section for different transitions of Pr 3+ for 4-phenyl thiosemicarbazones have been calculated.

Rai, Anita; Sengupta, Soumitra K.; Pandey, Om P.

2005-09-01

41

A New Antiviral Agent : 4-Bromo-3-methylisothiazole-5-carboxaldehyde thiosemicarbazone, M and B 7714  

Microsoft Academic Search

STIMULATED by reports of the antiviral activity of some thiosemicarbazones1, and particularly of the activity against neurovaccinia of isatin beta-thiosemicarbazone2,3, we sought to enhance the activity of these compounds by structural modification. Thus we synthesized N-ethylisatin beta-thiosemicarbazone independently of, but somewhat later than, Bauer and Sadler4. At the same time, we had been making a systematic study of the chemistry

R. Slack; K. R. H. Wooldridge; J. A. McFadzean; S. Squires

1964-01-01

42

Synthesis and cytotoxic activity of N-substituted thiosemicarbazones of 3-(3,4-methylenedioxy)phenylpropanal.  

PubMed

Five new N-substituted thiosemicarbazones of 3-(3,4-methylenedioxy)phenylpropanal were synthesized. Safrole, a natural product obtained from sassafras oil (Ocotea pretiosa), was oxidized to alcohol using BH3-THF and H2O2, followed by oxidation to aldehyde using pyridinium dichromate (PDC) and condensation with five N-substituted derivatives of thiosemicarbazide. Tests were performed to evaluate the cytotoxic activity with continuous chain KB cells (epidermoide carcinoma of the floor of the mouth). Compounds 5 and 6 showed IC50 values of 1.5 and 4.6 micrograms/ml, respectively. PMID:9639871

Joselice e Silva, M; Alves, A J; Do Nascimento, S C

1998-03-01

43

Biomass pyrolysis: Thermal decomposition mechanisms of furfural and benzaldehyde  

NASA Astrophysics Data System (ADS)

The thermal decompositions of furfural and benzaldehyde have been studied in a heated microtubular flow reactor. The pyrolysis experiments were carried out by passing a dilute mixture of the aromatic aldehydes (roughly 0.1%-1%) entrained in a stream of buffer gas (either He or Ar) through a pulsed, heated SiC reactor that is 2-3 cm long and 1 mm in diameter. Typical pressures in the reactor are 75-150 Torr with the SiC tube wall temperature in the range of 1200-1800 K. Characteristic residence times in the reactor are 100-200 ?sec after which the gas mixture emerges as a skimmed molecular beam at a pressure of approximately 10 ?Torr. Products were detected using matrix infrared absorption spectroscopy, 118.2 nm (10.487 eV) photoionization mass spectroscopy and resonance enhanced multiphoton ionization. The initial steps in the thermal decomposition of furfural and benzaldehyde have been identified. Furfural undergoes unimolecular decomposition to furan + CO: C4H3O-CHO (+ M) ? CO + C4H4O. Sequential decomposition of furan leads to the production of HC?CH, CH2CO, CH3C?CH, CO, HCCCH2, and H atoms. In contrast, benzaldehyde resists decomposition until higher temperatures when it fragments to phenyl radical plus H atoms and CO: C6H5CHO (+ M) ? C6H5CO + H ? C6H5 + CO + H. The H atoms trigger a chain reaction by attacking C6H5CHO: H + C6H5CHO ? [C6H6CHO]* ? C6H6 + CO + H. The net result is the decomposition of benzaldehyde to produce benzene and CO.

Vasiliou, AnGayle K.; Kim, Jong Hyun; Ormond, Thomas K.; Piech, Krzysztof M.; Urness, Kimberly N.; Scheer, Adam M.; Robichaud, David J.; Mukarakate, Calvin; Nimlos, Mark R.; Daily, John W.; Guan, Qi; Carstensen, Hans-Heinrich; Ellison, G. Barney

2013-09-01

44

Synthesis, characterization and biological evaluation of paeonol thiosemicarbazone analogues as mushroom tyrosinase inhibitors.  

PubMed

A series of hydroxy- and methoxy-substituted paeonol thiosemicarbazone analogues were synthesized as potential tyrosinase inhibitors and their inhibitory effects on mushroom tyrosinase and inhibitory mechanism were evaluated. Paeonol thiosemicarbazone analogues have been found exhibiting more remarkable inhibition than their indexcompounds on mushroom tyrosinase. Among them, compound 2,4-dihydroxy acetophenone-4-phenyl-3-thiosemicarbazone (d1) had the most potent inhibition activity with the IC50 value of 0.006 ± 0.001 mM, displayed as a reversible competitive inhibitor. The inhibitory ability of o- or p-substituted acetophenone thiosemicarbazones was: di-substituted acetophenone thiosemicarbazones>mono-substituted acetophenone thiosemicarbazones>non-substituted acetophenone thiosemicarbazones. Copper ions chelation assay explained that compound d1 exhibited competitive inhibition by forming a chelate with the copper ions at the catalytic domain of tyrosinase as well as indicate a 1.5:1 binding ratio of compound d1 with copper ions. In the fluorescence spectrum study, compound d1 behaved stronger fluorescence quenching on tyrosinase towards d1-Cu(2+) complex, inhibiting tyrosinase mainly by means of chelating the two copper ions in the active site. The newly synthesized compounds may serve as structural templates for designing and developing novel tyrosinase inhibitors. PMID:24120880

Zhu, Tian-Hua; Cao, Shu-Wen; Yu, Yan-Ying

2013-11-01

45

4-{Phen­yl[4-(6-phenyl-2,2?-bipyridin-4-yl)phen­yl]amino}­benzaldehyde  

PubMed Central

The title mol­ecule, C35H25N3O, is a tri­phenyl­amine derivative with the 4-position substituted by an aldehyde group, and the 4?-position substituted by a 6-phenyl-2,2?-bi­pyridine group. The whole mol­ecule is non-planar and the dihedral angle between the core benzene and pyridine rings is 36.96?(5)°. The dihedral angle between the phenyl and benzaldehyde groups bonded to the amine N atom is 70.86?(5)°. PMID:25249893

Zhang, Yu-yang; Pan, Jian-Ting; Huang, Jian-Yan

2014-01-01

46

Indole-7-carbaldehyde thiosemicarbazone as a flexidentate ligand toward ZnII, CdII, PdII and PtII ions: cytotoxic and apoptosis-inducing properties of the PtII complex.  

PubMed

A new thiosemicarbazone (LH2) derived from indole-7-carbaldehyde was synthesized and reacted with Zn(II), Cd(II), Pd(II) and Pt(II) salts. The reactions with zinc and cadmium salts in 2?:?1 (ligand-metal) molar ratio afforded complexes of the type MX2(LH2)2, (X = Cl, Br or OAc), in which the thiosemicarbazone acts as a neutral S-monodentate ligand. In the presence of potassium hydroxide, the reaction of LH2 with ZnBr2 resulted in deprotonation of the thiosemicarbazone at the hydrazine and indole nitrogens to form Zn(L)(CH3OH). The reaction of LH2 with K2PdCl4 in the presence of triethylamine, afforded Pd(L)(LH2) which contains two thiosemicarbazone ligands: one being dianionic N,N,S-tridentate while the other one is neutral S-monodentate. When PdCl2(PPh3)2 was used as the Pd(II) ion source, Pd(L)(PPh3) was obtained. In a similar manner, the analogous platinum complex, Pt(L)(PPh3), was synthesized. The thiosemicarbazone in the latter two complexes behaves in a dianionic N,N,S-tridentate fashion. The platinum complex was found to have significant cytotoxicity toward four cancer cells lines, namely MDA-MB-231, MCF-7, HT-29, and HCT-116 but not toward the normal liver WRL-68 cell line. The apoptosis-inducing properties of the Pt complex was explored through fluorescence microscopy visualization, DNA fragmentation analysis and propidium iodide flow cytometry. PMID:24442181

Ibrahim, Abeer A; Khaledi, Hamid; Hassandarvish, Pouya; Mohd Ali, Hapipah; Karimian, Hamed

2014-03-14

47

Preparation of Tin Chalcogenide Nanoparticles Using Tribenzyltin(IV) Semi and Thiosemicarbazone Precursors  

Microsoft Academic Search

The reactions of tribenzyltin(IV)chloride with one mole equivalent of sodium salts of semi- and thiosemicarbazone ligands gave complexes of the type Bz3SnL (L = semicarbazone or thiosemicarbazone moiety). These compounds have been characterized by elemental analysis, IR, H, C{H}, and Sn (in few cases), NMR spectroscopy, and thermogravimetric analysis. Thermal decomposition of complexes was carried out. The materials obtained were

Yogesh S. Niwate; Shivram S. Garje

2011-01-01

48

Die Resistenz des Mycobacterium tuberculosis gegen Ethionamid, Thiosemicarbazon und Isoxyl und ihre Beziehungen zueinander  

Microsoft Academic Search

Zusammenfassung An Stämmen von 522 Lungentuberkulösen wurde in 1596 Testungen die Empfindlichkeit gegen Isoxyl, Thiosemicarbazon und Ethionamid gleichzeitig geprüft. In diesem Routinematerial betrug die Häufigkeit einer Thiosemicarbazonresistenz 8,2%, der Isoxylresistenz 10,1% und der Ethionamidresistenz 6,5%. Die Kreuzresistenz zwischen Thiosemicarbazon und Ethionamid ist sehr häufig. In 75% war die Isoxylresistenz mit einer Thiosemicarbazonresistenz gekoppelt. Eine primäre Resistenz gegen Isoxyl wurde in

H. Eule; E. Werner

1967-01-01

49

Supramolecular interactions in biologically relevant compounds. 2-Pyrazineformamide thiosemicarbazones and some products of their cyclization  

NASA Astrophysics Data System (ADS)

Reaction of 2-cyanopyrazine with thiosemicarbazide or N-methylthiosemicarbazide afforded the (Z)-2-(amino(pyrazin-2-yl)methylene)hydrazinecarbothioamide (HPzAm4DH) and (Z)-2-(amino(pyrazin-2-yl)methylene)-N-methylhydrazine carbothioamide (HPzAm4M), respectively. (2Z,N?E)-N?-(4-Oxothiazolidin-2-ylidene)pyrazine-2-carbohydrazonamide (HPzAmot, 5) and (2Z,N?E)-N?-(3-methyl-4-oxothiazolidin-2-ylidene)pyrazine-2-carbohydrazonamide (MPzAmot, 7) have been synthesized from these thiosemicarbazones with chloroacetic or bromoacetic acids, using a conventional synthetic methodology and microwave-assisted organic reaction enhancement. The crystal structures of the thiosemicarbazones and their solvates [HPzAm4DH?1/2 MeOH (1), HPzAm4DH?H2O (2), HPzAm4M (3), HPzAm4M?2H2O (4)] and the 1,3-thiazolidin-4-ones (5 and 7) have been studied by X-ray diffractometry. All of the compounds were characterized by elemental analysis, mass spectrometry, FT-IR and 1H and 13C NMR spectroscopy. Several by-products have also been isolated in a crystalline form, namely 3-((Z,E)-N?-(4-oxothiazolidin-2-ylidene)carbamohydrazonium-yl)pyrazin-1-ium dibromide monohydrate, (H3PzAmot)Br2?H2O (6), 2-((5-(pyrazin-2-yl)-1H-1,2,4-triazol-3-yl)thio)acetic acid, (H2Pz124ttAc) (8), 2-amino-5-(pyrazin-2-yl)-1,3,4-thiadiazol-3-ium chloride monohydrate, (HPz134tda)Cl?H2O (9), and 2-(methylamino)-5-(pyrazin-2-yl)-1,3,4-thiadiazol-3-ium chloride N-methyl-5-(pyrazin-2-yl)-1,3,4-thiadiazol-2-amine solvate, (HMPz134tda)Cl?(MPz134tda) (10). The structures of these compounds were also analyzed by X-ray diffractometry. The microwave-assisted organic reaction method for synthesis is easy, convenient, and ecofriendly when compared to the traditional synthetic methods. Crystal analysis revealed that the compounds have extended 3D supramolecular networks through high levels of H-bonding and weak molecular interactions between the molecular moieties and solvent molecules. The novel synthons, which are sustained by Nsbnd H⋯N and Nsbnd H⋯O hydrogen bonding and other weak interactions, have been shown to assemble with 1,3-thizolidine-4-ones, 1,2,4-trizole, or 1,3,4-thiadiazole derivatives in a zigzag or herringbone architecture.

Castiñeiras, Alfonso; García-Santos, Isabel; Nogueiras, Silvia; Rodríguez-González, Iria; Rodríguez-Riobó, Raúl

2014-09-01

50

Benzaldehyde as an insecticidal, antimicrobial, and antioxidant compound produced by Photorhabdus temperata M1021.  

PubMed

The Photorhabdus temperata M1021 secretes toxic compounds that kill their insect hosts by arresting immune responses. Present study was aimed to purify the insecticidal and antimicrobial compound(s) from the culture extract of P. temperata M1021 through bioassay guided fractionation. An ethyl acetate (EtOAc) extract of the P. temperata M1021 exhibited 100% mortality in Galleria mellonella larvae within 72 h. In addition, EtOAc extract and bioactive compound 1 purified form the extract through to column chromatography, showed phenol oxidase inhibition up to 60% and 80% respectively. The analysis of (1)H and (13)C NMR spectra revealed the identity of pure compound as "benzaldehyde". The benzaldehyde showed insecticidal activity against G. mellonella in a dose-dependent manner and 100% insect mortality was observed at 108 h after injection of 8 mM benzaldehyde. In a PO inhibition assay, 4, 6, and 8 mM concentrations of benzaldehyde were found to inhibit PO activity about 15%, 42%, and 80% respectively. In addition, nodule formation was significantly (P < 0.05) inhibited by 4, 6, and 8 mM of benzaldehyde as compare to control. Moreover, benzaldehyde was found to have great antioxidant activity and maximum antioxidant activity was 52.9% at 8 mM benzaldehyde as compare to control. Antimicrobial activity was assessed by MIC values ranged from 6 mM 10 mM for bacterial strains and 8 mM to 10 mM for fungal strains. The results suggest that benzaldehyde could be applicable for developing novel insecticide for agriculture use. PMID:25626368

Ullah, Ihsan; Khan, Abdul Latif; Ali, Liaqat; Khan, Abdur Rahim; Waqas, Muhammad; Hussain, Javid; Lee, In-Jung; Shin, Jae-Ho

2015-02-01

51

Surface Plasmon Resonance Based Sensitive Immunosensor for Benzaldehyde Detection  

NASA Astrophysics Data System (ADS)

Fragrant compounds used to add flavor to beverages remain in the manufacturing line after the beverage manufacturing process. Line cleanliness before the next manufacturing cycle is difficult to estimate by sensory analysis, making excessive washing necessary. A new measurement system to determine line cleanliness is desired. In this study, we attempted to detect benzaldehyde (Bz) using an anti-Bz monoclonal antibody (Bz-Ab) and a surface plasmon resonance (SPR) sensor. We fabricated two types of sensor chips using self-assembled monolayers (SAMs) and investigated which sensor surface exhibited higher sensitivity. In addition, anti-Bz antibody conjugated with horseradish peroxidase (HRP-Bz-Ab) was used to enhance the SPR signal. A detection limit of ca. 9ng/mL (ppb) was achieved using an immobilized 4-carboxybenzaldehyde sensor surface using SAMs containing ethylene glycol. When the HRP-Bz-Ab concentration was reduced to 30ng/mL, a detection limit of ca. 4ng/mL (ppb) was achieved for Bz.

Onodera, Takeshi; Shimizu, Takuzo; Miura, Norio; Matsumoto, Kiyoshi; Toko, Kiyoshi

52

Synthesis, characterization and binding affinities of rhenium(I) thiosemicarbazone complexes for the estrogen receptor (?/?).  

PubMed

The binding affinities towards estrogen receptors (ERs) ? and ? of a set of thiosemicarbazone ligands (HL(n)) and their rhenium(I) carbonyl complexes [ReX(HL(n))(CO)3] (X=Cl, Br) were determined by a competitive standard radiometric assay with [(3)H]-estradiol. The ability of the coordinated thiosemicarbazone ligands to undergo deprotonation and the lability of the ReX bond were used as a synthetic strategy to obtain [Re(hpy)(L(n))(CO)3] (hpy=3- or 4-hydroxypyridine). The inclusion of the additional hpy ligand endows the new thiosemicarbazonate complexes with an improved affinity towards the estrogen receptors and, consequently, the values of the inhibition constant (Ki) could be determined for some of them. In general, the values of Ki for both ER subtypes suggest an appreciable selectivity towards ER?. PMID:25061691

Núñez-Montenegro, Ara; Carballo, Rosa; Vázquez-López, Ezequiel M

2014-11-01

53

Design, synthesis and biological evaluation of new aryl thiosemicarbazone as antichagasic candidates.  

PubMed

The present work reports on the synthesis, biological assaying and docking studies of a series of 12 aryl thiosemicarbazones, which were planned to act over two main enzymes, cruzain and trypanothione reductase. These enzymes are used as targets of trypanocidal activity in Chagas disease control with a minimal mutagenic profile. Three p-nitroaromatic thiosemicarbazones showed high activity against Trypanosoma cruzi in in vitro assays (IC50 < 57 ?M), and no mutagenic profile was observed in micronucleous tests. Although the in vitro inhibition test showed that 10-?M doses of eight compounds inhibited cruzain activity, no correlation was found between cruzain inhibition and trypanocidal activity. PMID:23851115

Blau, Lorena; Menegon, Renato Farina; Trossini, Gustavo H G; Molino, João Vitor Dutra; Vital, Drielli Gomes; Cicarelli, Regina Maria Barretto; Passerini, Gabriela Duó; Bosquesi, Priscila Longhin; Chin, Chung Man

2013-09-01

54

Antifungal activity of redox-active benzaldehydes that target cellular antioxidation  

PubMed Central

Background Disruption of cellular antioxidation systems should be an effective method for control of fungal pathogens. Such disruption can be achieved with redox-active compounds. Natural phenolic compounds can serve as potent redox cyclers that inhibit microbial growth through destabilization of cellular redox homeostasis and/or antioxidation systems. The aim of this study was to identify benzaldehydes that disrupt the fungal antioxidation system. These compounds could then function as chemosensitizing agents in concert with conventional drugs or fungicides to improve antifungal efficacy. Methods Benzaldehydes were tested as natural antifungal agents against strains of Aspergillus fumigatus, A. flavus, A. terreus and Penicillium expansum, fungi that are causative agents of human invasive aspergillosis and/or are mycotoxigenic. The yeast Saccharomyces cerevisiae was also used as a model system for identifying gene targets of benzaldehydes. The efficacy of screened compounds as effective chemosensitizers or as antifungal agents in formulations was tested with methods outlined by the Clinical Laboratory Standards Institute (CLSI). Results Several benzaldehydes are identified having potent antifungal activity. Structure-activity analysis reveals that antifungal activity increases by the presence of an ortho-hydroxyl group in the aromatic ring. Use of deletion mutants in the oxidative stress-response pathway of S. cerevisiae (sod1?, sod2?, glr1?) and two mitogen-activated protein kinase (MAPK) mutants of A. fumigatus (sakA?, mpkC?), indicates antifungal activity of the benzaldehydes is through disruption of cellular antioxidation. Certain benzaldehydes, in combination with phenylpyrroles, overcome tolerance of A. fumigatus MAPK mutants to this agent and/or increase sensitivity of fungal pathogens to mitochondrial respiration inhibitory agents. Synergistic chemosensitization greatly lowers minimum inhibitory (MIC) or fungicidal (MFC) concentrations. Effective inhibition of fungal growth can also be achieved using combinations of these benzaldehydes. Conclusions Natural benzaldehydes targeting cellular antioxidation components of fungi, such as superoxide dismutases, glutathione reductase, etc., effectively inhibit fungal growth. They possess antifungal or chemosensitizing capacity to enhance efficacy of conventional antifungal agents. Chemosensitization can reduce costs, abate resistance, and alleviate negative side effects associated with current antifungal treatments. PMID:21627838

2011-01-01

55

Involvement of manganese in conversion of phenylalanine to benzaldehyde by lactic acid bacteria  

Microsoft Academic Search

Degradation of amino acids by lactic acid bacteria (LAB) is important for the generation of flavor compounds during cheese ripening. We previously described that the conversion of phenylalanine to benzaldehyde in cell extracts of Lactoba- cillus plantarum (14) differs from the pathways described for fungi and for Pseudomonas putida (6, 8, 9, 11, 13, 18). In L. plantarum, the conversion

MASJA N. NIEROP GROOT; Bont de J. A. M

1999-01-01

56

Antifungal activity of redox-active benzaldehydes that target cellular antioxidation  

Technology Transfer Automated Retrieval System (TEKTRAN)

Many pathogenic fungi are becoming resistant to currently available drugs. Disruption of cellular antioxidation systems should be an effective method for control of fungal pathogens. Such disruption can be achieved with redox-active compounds. The aim of this study was to identify benzaldehydes that...

57

Growth of 4-(dimethylamino) benzaldehyde doped triglycine sulphate single crystals and its characterization  

Microsoft Academic Search

Single crystals of triglycine sulphate (TGS) doped with 1mol% of 4-(dimethylamino) benzaldehyde (DB) have been grown from aqueous solution at ambient temperature by slow evaporation technique. The effect of dopant on the crystal growth and dielectric, pyroelectric and mechanical properties of TGS crystal have been investigated. X-ray powder diffraction pattern for pure and doped TGS was collected to determine the

Chitharanjan Rai; K. Sreenivas; S. M. Dharmaprakash

2009-01-01

58

Chemo-sensitization of fungal pathogens to antimicrobial agents using benzaldehyde analogs  

Technology Transfer Automated Retrieval System (TEKTRAN)

Activity of conventional antifungal agents, fludioxonil, strobilurin and antimycinA, which target the oxidative and osmotic stress response systems, was elevated by co-application of certain analogs of benzaldehyde. Fungal tolerance to 2,3-dihydroxybenzaldehyde or 2,3-dihydroxybenzoic acid was foun...

59

The cyclohexadienylidenemethanone radical cation is a more stable distonic isomer of ionized benzaldehyde  

NASA Astrophysics Data System (ADS)

Quantum chemical calculations (G3B3 and B3LYP/6-311++G(d,p)) and tandem mass spectrometric experiments demonstrate the higher stability of 1,3-cyclohexadienylidenemethanone radical cation compared to ionized benzaldehyde. Characterized by a heat of formation of 833 kJ mol -1 (at 298 K), this ketene C 7H 6O rad + isomer is found 43 kJ mol -1 more stable. It has been generated by ion/molecule reaction between ionized benzaldehyde and neutral methanol, a new example of proton transport catalysis tautomerization. The greater stability of the ketene ion is due to the low IE of the neutral (7.49 eV).

Flammang, Robert; Dechamps, Noémie; Gerbaux, Pascal; Nam, Pham Cam; Nguyen, Minh Tho

2008-05-01

60

Rationalization of physicochemical characters of oxazolyl thiosemicarbazone analogs towards multi-drug resistant tuberculosis: a QSAR approach.  

PubMed

The emergence of multi-drug resistant (MDR) strains of Mycobacterium tuberculosis and the continuing pandemic of tuberculosis emphasizes the urgent need for the development of new and potent anti-tubercular agents. In an effort to develop new and more effective agents to treat tuberculosis emphasis was focused on quantification of structure-activity relationship of oxazolyl thiosemicarbazone derivatives. The de novo analysis gave insight to some important structural features i.e. nitro group on phenyl ring at R(1) position is optimal for the activity and might be responsible for electronic interaction, while phenyl ring at R position interact with the hydrophobic pocket more effectively as compared to unsubstituted or methyl substituted analogs. Hansch approach offered the understanding and parameterization of interactions of the inhibitor with receptor. Similarly QSAR analysis gave some important physicochemical properties, i.e. empirical aromatic index (ARR) and 3D-MoRSE code value of scattering angle at 8A(-1). These two physicochemical properties shall be helpful in the development of more potent analogs. PMID:17343958

Gupta, Revathi A; Gupta, Arun K; Soni, Love K; Kaskhedikar, S G

2007-08-01

61

Spectroscopic characterization of copper(II) complexes of indoxyl N(4)-methyl thiosemicarbazone  

NASA Astrophysics Data System (ADS)

New copper(II) complexes of indoxyl thiosemicarbazone (ITSC) of general composition CuL 2X 2 (where L: ITSC; X: Cl -, NO 3-, ClO 4-, NCS -) have been synthesized and characterized by elemental analysis, molar conductance, magnetic susceptibility measurements and spectral (electronic, IR, EPR, 1H NMR , Mass) studies. Cyclic voltammetry measurements show quasi-reversible Cu 2+/Cu 1+ couple. Various physico-chemical techniques suggest a tetragonal structure for these copper(II) complexes.

Chandra, Sulekh; Kumar, Umendra

2004-10-01

62

Quantum chemical study on asymmetric allylation of benzaldehyde in the presence of chiral allylboronate  

PubMed Central

The quantum chemical method is employed to study the modified asymmetric allylation of benzaldehyde controlled by diisopropyl D-(-)-tartrate auxiliary. All the structures are optimized completely at the B3LYP/6-31G(d,p) level. The (R)-secondary alcohol can be achieved mainly through a six-membered ring chair-like transition state structure. From the relative reaction rates theory the main product configuration predicted is in agreement with the experiment result. PMID:15909353

Chen, Wan-suo; Chen, Zhi-rong

2005-01-01

63

Olfactory receptors on the maxillary palps of small ermine moth larvae: evolutionary history of benzaldehyde sensitivity  

PubMed Central

In lepidopterous larvae the maxillary palps contain a large portion of the sensory equipment of the insect. Yet, knowledge about the sensitivity of these cells is limited. In this paper a morphological, behavioral, and electrophysiological investigation of the maxillary palps of Yponomeuta cagnagellus (Lepidoptera: Yponomeutidae) is presented. In addition to thermoreceptors, CO2 receptors, and gustatory receptors, evidence is reported for the existence of two groups of receptor cells sensitive to plant volatiles. Cells that are mainly sensitive to (E)-2-hexenal and hexanal or to (Z)-3-hexen-1-ol and 1-hexanol were found. Interestingly, a high sensitivity for benzaldehyde was also found. This compound is not known to be present in Euonymus europaeus, the host plant of the monophagous Yponomeuta cagnagellus, but it is a prominent compound in Rosaceae, the presumed hosts of the ancestors of Y. cagnagellus. To elucidate the evolutionary history of this sensitivity, and its possible role in host shifts, feeding responses of three Yponomeuta species to benzaldehyde were investigated. The results confirm the hypothesis that the sensitivity to benzaldehyde evolved during the ancestral shift from Celastraceae to Rosaceae and can be considered an evolutionary relict, retained in the recently backshifted Celastraceae-specialist Y. cagnagellus. PMID:17372741

Xu, Sen; Menken, Steph B. J.

2007-01-01

64

Olfactory receptors on the maxillary palps of small ermine moth larvae: evolutionary history of benzaldehyde sensitivity.  

PubMed

In lepidopterous larvae the maxillary palps contain a large portion of the sensory equipment of the insect. Yet, knowledge about the sensitivity of these cells is limited. In this paper a morphological, behavioral, and electrophysiological investigation of the maxillary palps of Yponomeuta cagnagellus (Lepidoptera: Yponomeutidae) is presented. In addition to thermoreceptors, CO(2) receptors, and gustatory receptors, evidence is reported for the existence of two groups of receptor cells sensitive to plant volatiles. Cells that are mainly sensitive to (E)-2-hexenal and hexanal or to (Z)-3-hexen-1-ol and 1-hexanol were found. Interestingly, a high sensitivity for benzaldehyde was also found. This compound is not known to be present in Euonymus europaeus, the host plant of the monophagous Yponomeuta cagnagellus, but it is a prominent compound in Rosaceae, the presumed hosts of the ancestors of Y. cagnagellus. To elucidate the evolutionary history of this sensitivity, and its possible role in host shifts, feeding responses of three Yponomeuta species to benzaldehyde were investigated. The results confirm the hypothesis that the sensitivity to benzaldehyde evolved during the ancestral shift from Celastraceae to Rosaceae and can be considered an evolutionary relict, retained in the recently backshifted Celastraceae-specialist Y. cagnagellus. PMID:17372741

Roessingh, Peter; Xu, Sen; Menken, Steph B J

2007-06-01

65

The cytotoxicity of benzaldehyde nitrogen mustard-2-pyridine carboxylic acid hydrazone being involved in topoisomerase II? inhibition.  

PubMed

The antitumor property of iron chelators and aromatic nitrogen mustard derivatives has been well documented. Combination of the two pharmacophores in one molecule in drug designation is worth to be explored. We reported previously the syntheses and preliminary cytotoxicity evaluation of benzaldehyde nitrogen mustard pyridine carboxyl acid hydrazones (BNMPH) as extended study, more tumor cell lines (IC50 for HepG2: 26.1 ± 3.5 ?M, HCT-116: 57.5 ± 5.3 ?M, K562: 48.2 ± 4.0 ?M, and PC-12: 19.4 ± 2.2 ?M) were used to investigate its cytotoxicity and potential mechanism. In vitro experimental data showed that the BNMPH chelating Fe(2+) caused a large number of ROS formations which led to DNA cleavage, and this was further supported by comet assay, implying that ROS might be involved in the cytotoxicity of BNMPH. The ROS induced changes of apoptosis related genes, but the TFR1 and NDRG1 metastatic genes were not obviously regulated, prompting that BNMPH might not be able to deprive Fe(2+) of ribonucleotide reductase. The BNMPH induced S phase arrest was different from that of iron chelators (G1) and alkylating agents (G2). BNMPH also exhibited its inhibition of human topoisomerase II?. Those revealed that the cytotoxic mechanism of the BNMPH could stem from both the topoisomerase II inhibition, ROS generation and DNA alkylation. PMID:24995306

Fu, Yun; Zhou, Sufeng; Liu, Youxun; Yang, Yingli; Sun, Xingzhi; Li, Changzheng

2014-01-01

66

Benzyl Derivatives with in Vitro Binding Affinity for Human Opioid Receptors and Cannabinoid Receptors from the Fungus Eurotium repens  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bioassay-guided fractionation of the fungus Eurotium repens resulted in the isolation of two benzyl derivatives, repenol A (1) and repenol B (2). Seven known secondary metabolites were also isolated including five benzaldehyde compounds, flavoglaucin (3), tetrahydroauroglaucin (4), dihydroauroglauci...

67

On the verification of binding modes of p-dimethylaminobenzaldehyde thiosemicarbazone with mercury(II). The solid state studies  

NASA Astrophysics Data System (ADS)

Two coordination compounds of p-dimethylaminobenzaldehyde thiosemicarbazone, fluorescent chemosensor, have been synthesised from the mercury(II) nitrate and mercury(II) chloride, and subsequently characterised by IR spectroscopy, thermal analysis, as well as single crystal X-ray diffraction technique. The inorganic anion has a distinct influence on binding mode of thiosemicarbazone ligand to Hg(II) ion. In both compounds the metal to ligand stoichiometry is 1:2 and the organic ligands coordinate to Hg ion in the neutral thione form, but they differ in a ligand binding mode and the conformation of the ligand. The crystal packing of mercury(II) nitrate complex with thiosemicarbazone is controlled by the mercury chelate ring-phenylene ring ?···? stacking interactions.

Trzesowska-Kruszynska, Agata

2014-08-01

68

Enhanced Benzaldehyde Tolerance in Zymomonas mobilis Biofilms and the Potential of Biofilm Applications in Fine-Chemical Production  

PubMed Central

Biotransformation plays an increasingly important role in the industrial production of fine chemicals due to its high product specificity and low energy requirement. One challenge in biotransformation is the toxicity of substrates and/or products to biocatalytic microorganisms and enzymes. Biofilms are known for their enhanced tolerance of hostile environments compared to planktonic free-living cells. Zymomonas mobilis was used in this study as a model organism to examine the potential of surface-associated biofilms for biotransformation of chemicals into value-added products. Z. mobilis formed a biofilm with a complex three-dimensional architecture comprised of microcolonies with an average thickness of 20 ?m, interspersed with water channels. Microscopic analysis and metabolic activity studies revealed that Z. mobilis biofilm cells were more tolerant to the toxic substrate benzaldehyde than planktonic cells were. When exposed to 50 mM benzaldehyde for 1 h, biofilm cells exhibited an average of 45% residual metabolic activity, while planktonic cells were completely inactivated. Three hours of exposure to 30 mM benzaldehyde resulted in sixfold-higher residual metabolic activity in biofilm cells than in planktonic cells. Cells inactivated by benzaldehyde were evenly distributed throughout the biofilm, indicating that the resistance mechanism was different from mass transfer limitation. We also found that enhanced tolerance to benzaldehyde was not due to the conversion of benzaldehyde into less toxic compounds. In the presence of glucose, Z. mobilis biofilms in continuous cultures transformed 10 mM benzaldehyde into benzyl alcohol at a steady rate of 8.11 g (g dry weight)?1 day?1 with a 90% molar yield over a 45-h production period. PMID:16461720

Li, Xuan Zhong; Webb, Jeremy S.; Kjelleberg, Staffan; Rosche, Bettina

2006-01-01

69

Antiproliferative activities of iron and platinum conjugates of salicylaldehyde semi-/thiosemicarbazones against C6 glioma cells.  

PubMed

The identification of novel therapeutic agents for the management of malignant gliomas represents an area of active research. Here, we show that among the iron and platinum complexes of 2-hydroxybenzaldehyde semi-/thiosemicarbazones the latter inhibits the growth of C6 glioma cells in vitro with an IC50 value of 45 microM. Structural characterization reveals iron complexes to be octahedral having intermediate S = 3/2 spin states while platinum complexes are found to be square planar moieties. Our findings suggest that the platinum compounds of 2-hydroxybenzaldehyde thiosemicarbazone are potential candidates for the treatment of malignant gliomas. PMID:15913848

Patole, J; Padhye, S; Moodbidri, M S; Shirsat, N

2005-10-01

70

Probing the active center of benzaldehyde lyase with substitutions and the pseudo-substrate analog benzoylphosphonic acid methyl ester  

PubMed Central

Benzaldehyde lyase (BAL) catalyzes the reversible cleavage of (R)-benzoin to benzaldehyde utilizing thiamin diphosphate and Mg2+ as cofactors. The enzyme is important for the chemoenzymatic synthesis of a wide range of compounds via its carboligation reaction mechanism. In addition to its principal functions, BAL can slowly decarboxylate aromatic amino acids such as benzoylformic acid. It is also intriguing mechanistically due to the paucity of acid-base residues at the active center that can participate in proton transfer steps thought to be necessary for these type of reactions. Here methyl benzoylphosphonate, an excellent electrostatic analog of benzoylformic acid, is used to probe the mechanism of benzaldehyde lyase. The structure of benzaldehyde lyase in its covalent complex with methyl benzoylphosphonate was determined to 2.49 Å (PDB ID: 3D7K) and represents the first structure of this enzyme with a compound bound in the active site. No large structural reorganization was detected compared to the complex of the enzyme with thiamin diphosphate. The configuration of the predecarboxylation thiamin-bound intermediate was clarified by the structure. Both spectroscopic and X-ray structural studies are consistent with inhibition resulting from the binding of MBP to the thiamin diphosphate in the active centers. We also delineated the role of His29 (the sole potential acid-base catalyst in the active site other than the highly conserved Glu50) and Trp163 in cofactor activation and catalysis by benzaldehyde lyase. PMID:18570438

Brandt, Gabriel S.; Nemeria, Natalia; Chakraborty, Sumit; McLeish, Michael J.; Yep, Alejandra; Kenyon, George L.; Petsko, Gregory A.; Jordan, Frank; Ringe, Dagmar

2009-01-01

71

Binding of NADH to horse liver alcohol dehydrogenase: dependence on concentration of benzaldehyde and benzyl alcohol.  

PubMed

Equilibrium titration measurements of NAD+ and NADH in the presence of stoichiometric amounts of liver alcohol dehydrogenase (10(-6)N less than enzyme = coenzyme less than 10(-4)N) have been carried out by using the couple of substrates benzyl alcohol-benzaldehyde, at pH 7.0 and 8.75, in the absence and in the presence of isobutyramide. The results obtained have been unsuccessfully analyzed on the basis of the widely accepted compulsory order model which assumes functional equivalence and independence of the enzyme sites. PMID:6385034

Bignetti, E

1984-01-01

72

Ligational behavior of thiosemicarbazone, semicarbazone and thiocarbohydrazone ligands towards VO(IV), Ce(III), Th(IV) and UO2(VI) ions: synthesis, structural characterization and biological studies.  

PubMed

Mono- and binuclear VO(IV), Ce(III), Th(IV) and UO(2)(VI) complexes of thiosemicarbazone, semicarbazone and thiocarbohydrazone ligands derived from 4,6-diacetylresorcinol were synthesized. The structures of these complexes were elucidated by elemental analyses, IR, UV-vis, ESR, (1)H NMR and mass spectra as well as conductivity and magnetic susceptibility measurements and thermal analyses. The thiosemicarbazone (H(4)L(1)) and the semicarbazone (H(4)L(2)) ligands behave as dibasic pentadentate ligands in case of VO(IV) and UO(2)(VI) complexes, tribasic pentadentate in case of Ce(III) complexes and monobasic pentadentate in case of Th(IV) complexes. However, the thiocarbohydrazone ligand (H(3)L(3)) acts as a monobasic tridentate ligand in all complexes except the VO(IV) complex in which it acts as a dibasic tridentate ligand. The antibacterial and antifungal activities were also tested against Rhizobium bacteria and Fusarium-Oxysporium fungus. The metal complexes of H(4)L(1) ligand showed a higher antibacterial effect than the free ligand while the other ligands (H(4)L(2) and H(3)L(3)) showed a higher effect than their metal complexes. The antifungal effect of all metal complexes is lower than the free ligands. PMID:19963432

Shebl, M; Seleem, H S; El-Shetary, B A

2010-01-01

73

Synthesis, crystal structure and biological activity of thiophene-2-carboxaldehyde thiosemicarbazone and its tin complexes  

Microsoft Academic Search

Thiophene-2-carboxaldehyde thiosemicarbazone, C4H3S–CH?N–NH–C(S)NH2 (tctscH) obtained by the condensation reaction of thiophene-2-carboxaldehyde with thiosemicarbazide forms SnPh2Cl(tctsc), 1 and SnCl2(tctsc)2, 2 with SnPh2Cl2 and SnPhCl3 in 1:1 and 1:2 tin:ligand molar ratios, respectively. The crystal structure determination shows that in both 1 and 2, tctscH is deprotonated and functions as an anionic bidentate ligand, co-ordinating to the tin atom through its azomethine-N

Siang-Guan Teoh; Show-Hing Ang; Hoong-Kun Fun; Chi-Wi Ong

1999-01-01

74

Syntheses and spectroscopic studies on zinc(II) and mercury(II) complexes of isatin-3-thiosemicarbazone  

NASA Astrophysics Data System (ADS)

Zinc(II) and mercury(II) complexes were prepared by reacting isatin-3-thiosemicarbazone (ISTSCH) with zinc(II) acetate or mercury(II) bromide. The complexes were characterized by IR, Raman, diffuse reflectance, 1H and 13C NMR spectra and elemental analysis. Tetrahedral structures for Zn(ISTSC) 2 and Hg(ISTSCH)Br 2 are suggested.

Akinchan, N. T.; Dro?d?ewski, P. M.; Holzer, W.

2002-10-01

75

Growth of 4-(dimethylamino) benzaldehyde doped triglycine sulphate single crystals and its characterization  

NASA Astrophysics Data System (ADS)

Single crystals of triglycine sulphate (TGS) doped with 1 mol% of 4-(dimethylamino) benzaldehyde (DB) have been grown from aqueous solution at ambient temperature by slow evaporation technique. The effect of dopant on the crystal growth and dielectric, pyroelectric and mechanical properties of TGS crystal have been investigated. X-ray powder diffraction pattern for pure and doped TGS was collected to determine the lattice parameters. FTIR spectra were employed to confirm the presence of 4-(dimethylamino) benzaldehyde in TGS crystal, qualitatively. The dielectric permittivity has been studied as a function of temperature by cooling the sample at a rate of 1 °C/min. An increase in the Curie temperature Tc=51 °C (for pure TGS, Tc=48.5 °C) and decrease in maximum permittivity has been observed for doped TGS when compared to pure TGS crystal. Pyroelectric studies on doped TGS were carried out to determine pyroelectric coefficient. The Vickers's hardness of the doped TGS crystals along (0 1 0) face is higher than that of pure TGS crystal for the same face. Domain patterns on b-cut plates were observed using scanning electron microscope. The low dielectric constant, higher pyroelectric coefficient and higher value of hardness suggest that doped TGS crystals could be a potential material for IR detectors.

Rai, Chitharanjan; Sreenivas, K.; Dharmaprakash, S. M.

2009-11-01

76

Investigation of the l-phenylacetylcarbinol process to substituted benzaldehydes of interest.  

PubMed

The large scale industrial manufacture of the nasal decongestant pseudoephedrine is typically carried out by the reductive amination of l-phenylacetylcarbinol (l-PAC), which in turn is produced via the biotransformation of benzaldehyde using yeast. In recent years there has been increasing legislative control of the supply of pseudoephedrine due to it being diverted for the clandestine production of methylamphetamine and there is some evidence that a number of clandestine drug laboratory chemists have considered the application of the l-PAC process to manufacture their own pseudoephedrine. This work examined the use of a number of substituted benzaldehydes for the manufacture of the corresponding substituted l-PAC analogue followed by reductive amination to the corresponding substituted pseudoephedrine/ephedrine analogues. These substituted pseudoephedrine/ephedrine analogues were either reduced or oxidised to determine the feasibility of producing the corresponding methylamphetamine or methcathinone analogues. As a result, the l-PAC process was identified as a viable route for synthesis of substituted methylamphetamines and methcathinones. PMID:24447451

Maroney, Kerrie Anne N; Culshaw, Peter N; Wermuth, Urs D; Cresswell, Sarah L

2014-02-01

77

Synthesis and biological evaluation of some new N4-aryl substituted 5-chloroisatin-3-thiosemicarbazones.  

PubMed

A new series of sixteen N4-aryl substituted 5-chloroisatin-3-thiosemicarbazones 2a-2p has been synthesized, characterized and tested for selected biological activities i.e. cytotoxicity, phytotoxicity and urease inhibition. In the brine shrimp bioassay, all the synthesized compounds gave LD50 values>2.30x10(-4) M-2.79x10(-4) M and were, therefore, found to be almost inactive, whereas in phytotoxicity assay, regardless of the nature of aryl substituents, they displayed weak to moderate (5-40%) phytotoxic activity at the highest tested concentrations (500 or 1000 ?g/mL). In urease inhibition bioassay, compounds 2a, 2c, 2e, 2f, 2k and 2m exhibited relatively a higher degree of urease inhibition with IC50 values ranging from 38.91 ?M to 76.65 ?M and thus proved to be potent inhibitors of the enzyme. Of these, 2f and 2m displayed pronounced inhibition with IC50 values 38.91 ?M and 39.50 ?M, respectively, and may act as lead compounds for further studies. Structure-activity relationship (SAR) studies revealed that electronic effects of the substituents about the phenyl ring at N4 of the thiosemicarbazone moiety played an important role in enhancing the urease inhibitory potential of some of the synthesized compounds. PMID:22530899

Pervez, Humayun; Ramzan, Muhammad; Yaqub, Muhammad; Nasim, Faiz-ul-Hassan; Khan, Khalid Mohammed

2012-05-01

78

Chemical reactivity and skin sensitization potential for benzaldehydes: can Schiff base formation explain everything?  

PubMed

Skin sensitizers chemically modify skin proteins rendering them immunogenic. Sensitizing chemicals have been divided into applicability domains according to their suspected reaction mechanism. The widely accepted Schiff base applicability domain covers aldehydes and ketones, and detailed structure-activity-modeling for this chemical group was presented. While Schiff base formation is the obvious reaction pathway for these chemicals, the in silico work was followed up by limited experimental work. It remains unclear whether hydrolytically labile Schiff bases can form sufficiently stable epitopes to trigger an immune response in the living organism with an excess of water being present. Here, we performed experimental studies on benzaldehydes of highly differing skin sensitization potential. Schiff base formation toward butylamine was evaluated in acetonitrile, and a detailed SAR study is presented. o-Hydroxybenzaldehydes such as salicylaldehyde and the oakmoss allergens atranol and chloratranol have a high propensity to form Schiff bases. The reactivity is highly reduced in p-hydroxy benzaldehydes such as the nonsensitizing vanillin with an intermediate reactivity for p-alkyl and p-methoxy-benzaldehydes. The work was followed up under more physiological conditions in the peptide reactivity assay with a lysine-containing heptapeptide. Under these conditions, Schiff base formation was only observable for the strong sensitizers atranol and chloratranol and for salicylaldehyde. Trapping experiments with NaBH?CN showed that Schiff base formation occurred under these conditions also for some less sensitizing aldehydes, but the reaction is not favored in the absence of in situ reduction. Surprisingly, the Schiff bases of some weaker sensitizers apparently may react further to form stable peptide adducts. These were identified as the amides between the lysine residues and the corresponding acids. Adduct formation was paralleled by oxidative deamination of the parent peptide at the lysine residue to form the peptide aldehyde. Our results explain the high sensitization potential of the oakmoss allergens by stable Schiff base formation and at the same time indicate a novel pathway for stable peptide-adduct formation and peptide modifications by aldehydes. The results thus may lead to a better understanding of the Schiff base applicability domain. PMID:22950880

Natsch, Andreas; Gfeller, Hans; Haupt, Tina; Brunner, Gerhard

2012-10-15

79

Derivatives  

NSDL National Science Digital Library

Murray Bourne developed the Interactive Mathematics site while working as a mathematics lecturer at Ngee Ann Polytechnic in Singapore. The site contains numerous mathematics tutorials and resources for students and teachers alike. This specific page is focused on differentiation, or finding derivatives. Bourne walks users through an introduction to differentiation and limits, and then moves on to more specific applications like rate of change, derivatives of polynomials, and differentiating powers of a function. Each topic includes graphs and interactive materials designed to aid users in understanding the presented concepts. The information here is presented in a clear, straightforward manner that is appropriate for introductory and advanced calculus students alike.

Bourne, Murray

2008-04-22

80

Derivate  

NSDL National Science Digital Library

In this activity, students input functions in order to calculate the derivative and tangent line of that function. This activity allows students to explore tangent lines of various functions. This activity includes supplemental materials, including background information about the topics covered, a description of how to use the application, and exploration questions for use with the java applet.

2010-01-01

81

Effect of ruthenium complexation on trypanocidal activity of 5-nitrofuryl containing thiosemicarbazones.  

PubMed

In the search of new therapeutic tools for the treatment of American Trypanosomiasis, the largest parasitic disease burden in the American continent, three series of novel ruthenium complexes of the formula [RuCl(2)(HL)(2)], [RuCl(3)(dmso)(HL)] and [RuCl(PPh(3))(L)(2)] with bioactive 5-nitrofuryl containing thiosemicarbazones as ligands (HL neutral, L monoanionic) were synthesized and characterized. Their in vitro growth inhibition activity against Trypanosoma cruzi and the effect of co-ligands in related physicochemical properties i.e. nitro moiety redox potential, lipophilicity and free radical scavenger capacity were evaluated. Results show that although a loss of activity was observed as a consequence of ruthenium complexation, lipophilicity and free radical scavenger capacity of the obtained complexes could be correlated to their trypanocidal effect. PMID:19783078

Pagano, Mariana; Demoro, Bruno; Toloza, Jeanette; Boiani, Lucía; González, Mercedes; Cerecetto, Hugo; Olea-Azar, Claudio; Norambuena, Ester; Gambino, Dinorah; Otero, Lucía

2009-12-01

82

Structural and spectral perspectives of a novel thiosemicarbazone synthesized from di-2-pyridyl ketone and 4-phenyl-3-thiosemicarbazide  

NASA Astrophysics Data System (ADS)

A new thiosemicarbazone, HL is synthesized from di-2-pyridyl ketone and 4-phenyl-3-thiosemicarbazide and structurally and spectrochemically characterized. 1H NMR, 13C NMR, COSY, HMQC and IR spectra of the compound are studied and the proton magnetic resonance spectrum reveals some unprecedented observations. The thione form is predominant in the solid state, as supported by the crystal structure and IR data, while a thiol-thione equilibrium is proposed in the solution state by NMR studies. The compound crystallizes into a monoclinic lattice with space group C2/ c and the ZE conformation is exhibited by the thiosemicarbazone. Intra- and intermolecular hydrogen-bonding interactions give rise to a two-dimensional packing in the crystal lattice.

Suni, V.; Prathapachandra Kurup, M. R.; Nethaji, Munirathinam

2006-01-01

83

Coordination of nitro-thiosemicarbazones to ruthenium(II) as a strategy for anti-trypanosomal activity improvement.  

PubMed

Complexes [RuCl(H4NO(2)Fo4M)(bipy)(dppb)]PF(6) (1), [RuCl(H4NO(2)Fo4M)(Mebipy)(dppb)]PF(6) (2), [RuCl(H4NO(2)Fo4M)(phen)(dppb)]PF(6) (3), [RuCl(H4NO(2)Ac4M)(bipy)(dppb)]PF(6) (4), [RuCl(H4NO(2)Ac4M)(Mebipy)(dppb)]PF(6) (5) and [RuCl(H4NO(2)Ac4M)(phen)(dppb)]PF(6) (6) with N(4)-methyl-4-nitrobenzaldehyde thiosemicarbazone (H4NO(2)Fo4M) and N(4)-methyl-4-nitroacetophenone thiosemicarbazone (H4NO(2)Ac4M) were obtained from [RuCl(2)(bipy)(dppb)], [RuCl(2)(Mebipy)(dppb)], and [RuCl(2)(phen)(dppb)], (dppb = 1,4-bis(diphenylphospine)butane; bipy = 2,2'-bipyridine; Mebipy = 4,4'-dimethyl-2,2'-bipyridine; phen = 1,10-phenanthroline). In all cases the thiosemicarbazone is attached to the metal center through the sulfur atom. Complexes (1-6), together with the corresponding ligands and the Ru precursors were evaluated for their ability to in vitro suppress the growth of Trypanosoma cruzi. All complexes were more active than their corresponding ligands and precursors. Complexes (1-3) and (5) revealed to be the most active among all studied compounds with ID(50) = 0.6-0.8 microM. In all cases the association of the thiosemicarbazone with ruthenium, dppb and bipyridine or phenanthroline in one same complex proved to be an excellent strategy for activity improvement. PMID:20363536

Rodrigues, Claudia; Batista, Alzir A; Ellena, Javier; Castellano, Eduardo E; Benítez, Diego; Cerecetto, Hugo; González, Mercedes; Teixeira, Letícia R; Beraldo, Heloisa

2010-07-01

84

Bp44mT: an orally active iron chelator of the thiosemicarbazone class with potent anti-tumour efficacy  

PubMed Central

BACKGROUND AND PURPOSE Our previous studies demonstrated that a thiosemicarbazone iron chelator (di-2-pyridylketone-4,4-dimethyl-3-thiosemicarbazone; Dp44mT) possesses potent and selective anti-cancer activity but led to cardiotoxicity at non-optimal doses. In this study, we examined the in vivo anti-tumour efficacy and tolerability of a new-generation 2-benzoylpyridine thiosemicarbazone iron chelator (2-benzoylpyridine-4,4-dimethyl-3-thiosemicarbazone; Bp44mT) administered via the oral or i.v. routes. EXPERIMENTAL APPROACH BpT chelators were tested in vitro against human lung cancer cells (DMS-53) and in vivo in DMS-53 tumour xenografts in mice. The toxicity of Bp44mT in vivo and its effects on the expression of iron-regulated molecules involved in growth and cell cycle control were investigated. KEY RESULTS Administration of Bp44mT by either route resulted in marked dose-dependent inhibition of tumour growth. When administered at 50 mg·kg?1 via oral gavage three times per week for 23 days, the net xenograft growth was inhibited by 75%, compared with vehicle-treated mice. Toxicological examination showed reversible alterations including slight reduction of RBC count, with a decrease of liver and splenic iron levels, which confirmed iron chelation in vivo. Importantly, in contrast to Dp44mT, the chelator-treated mice did not show cardiac histological abnormalities. There was also no significant weight loss in mice, suggesting oral administration of Bp44mT was well tolerated. CONCLUSIONS AND IMPLICATIONS This is the first study to show that Bp44mT can be given orally with potent anti-tumour efficacy. Oral administration of a novel and effective chemotherapeutic agent provides the benefits of convenience for chronic dosing regimens. PMID:21658021

Yu, Y; Rahmanto, Y Suryo; Richardson, DR

2012-01-01

85

Preparation and biodistribution studies of a radiogallium-acetylacetonate bis (thiosemicarbazone) complex in tumor-bearing rodents.  

PubMed

Various radiometal complexes have been developed for tumor imaging, especially Ga-68 tracer. In the present study, the development of a radiogallium bis-thiosemicarbazone complex has been reported. [(67)Ga] acetylacetonate bis(thiosemicarbazone) complex ([(67)Ga] AATS) was prepared starting [(67)Ga]Gallium acetate and freshly prepared acetylacetonate bis (thiosemicarbazone) (AATS) in 30 min at 90°C. The partition co-efficient and the stability of the tracer were determined in final solution (25°C) and the presence of human serum (37°C) up to 24 h. The biodistribution of the labeled compound in wild-type and fibrosarcoma-bearing rodents were determined up to 72 h. The radiolabled Ga complex was prepared in high radiochemical purity (> 97%, HPLC) followed by initial biodistribution data with the significant tumor accumulation of the tracer in 2 h which is far higher than free Ga-67 cation while the compound wash-out is significantly faster. Above-mentioned pharmacokinetic properties suggest an interesting radiogallium complex while prepared by the PET Ga radioisotope, (68)Ga, in accordance with the physical half life, for use in fibrosarcoma tumors, and possibly other malignancies. PMID:24250475

Jalilian, Amir Reza; Yousefnia, Hassan; Shafaii, Kamaleddin; Novinrouz, Aytak; Rajamand, Amir Abbas

2012-01-01

86

Screening organometallic binuclear thiosemicarbazone ruthenium complexes as potential anti-tumour agents: cytotoxic activity and human serum albumin binding mechanism.  

PubMed

Four complexes combining the {Ru(p-cym)} moiety (p-cym = para-cymene) with thiosemicarbazone (TSC) ligands containing the 5-nitrofuryl pharmacophore were investigated in vitro for their properties as prospective anti-tumour agents. The compounds are dimeric structures of general formula [Ru2(p-cym)2(L)2]X2 where X = Cl(-), PF6(-) and L = deprotonated 5-nitrofuraldehyde TSC (L1), and the N-methyl (L2), N-ethyl (L3) and N-phenyl (L4) derivatives. The precursor [RuCl2(p-cym)]2, all TSC ligands L1-L4and their corresponding complexes 1-4 were screened in vitro for their cytotoxicity against a range of human cancer cell lines (HL-60 acute promyelocytic leukemia, A2780 ovarian adenocarcinoma, MCF7 breast adenocarcinoma and PC3 grade IV prostate carcinoma). While the precursor complex was found to be inactive and L4 exhibited moderate activity only in the MCF7 cell line, the coordination of L4 to the {Ru(p-cym)} moiety remarkably enhanced the activity of the whole complex. In fact, complex 4 [Ru2(p-cym)2(L4)2]Cl2 was found to be the most active agent of the whole series, and was studied further (as well as complex 1 for comparison). Concerning the mode of action, the mechanism of cell death for both 1 and 4 seemed to be related to apoptotic processes, and they strongly interacted with tubulin (involved in the cell cycle) and with integrin (involved in the cytoskeleton formation). As an approach to their pharmacokinetics, the interaction of 1 and 4 with human serum albumin (HSA) was assessed. A quantitative model for the binding of 4 to HSA is proposed from Circular Dichroism data, and validated by fluorescence results. Models of Förster resonance energy transfer and fluorescence quenching afforded the distance of 4 to the lone Trp214 residue. Importantly, HSA binding enhanced the cytotoxicity of 4 and correlated well with the HSA binding data. Our results consistently indicate that [Ru2(p-cymene)2(L4)2]Cl2 is quite promising as a prospective metallodrug for cancer chemotherapy. PMID:23519281

Demoro, Bruno; de Almeida, Rodrigo F M; Marques, Fernanda; Matos, Cristina P; Otero, Lucía; Costa Pessoa, João; Santos, Isabel; Rodríguez, Alejandra; Moreno, Virtudes; Lorenzo, Julia; Gambino, Dinorah; Tomaz, Ana Isabel

2013-05-21

87

Improved and efficient synthesis of chiral N,P-ligands via cyclic sulfamidates for asymmetric addition of butyllithium to benzaldehyde.  

PubMed

A robust and scaleable route to chiral 1-isopropylamino-2-(diphenylphosphino)ethanes is described via the ring-opening of chiral, cyclic sulfamidates with potassium diphenylphosphide (KPPh(2)). The novel protocol offers a robust access to gram quantities of chiral amino phosphinoethanes in high yields. The Li-amides of the chiral aminophosphines were evaluated as chiral ligands in the asymmetric addition of n-butyllithium (BuLi) to benzaldehyde, yielding 1-phenylpentanol up to 98% ee. PMID:17696545

Rönnholm, Petra; Södergren, Mikael; Hilmersson, Göran

2007-09-13

88

Flow Injection Analysis of Mercury Using 4-(Dimethylamino) Benzaldehyde-4-Ethylthiosemicarbazone as the Ionophore of a Coated Wire Electrode  

PubMed Central

A flow injection analysis (FIA) incorporating a thiosemicarbazone-based coated wire electrode (CWE) was developed method for the determination of mercury(II). A 0.1 M KNO3 carrier stream with pH between 1 and 5 and flow rate of 1 mL·min?1 were used as optimum parameters. A linear plot within the concentration range of 5 × 10?6–0.1 M Hg(II), slope of 27.8 ± 1 mV per decade and correlation coefficient (R2) of 0.984 were obtained. The system was successfully applied for the determination of mercury(II) in dental amalgam solutions and spiked environmental water samples. Highly reproducible measurements with relative standard deviation (RSD < 1% (n = 3)) were obtained, giving a typical throughput of 30 samples·h?1. PMID:23202196

Tahir, Tara F.; Salhin, Abdussalam; Ghani, Sulaiman Ab

2012-01-01

89

Synthesis and Toxicity Evaluation of Some N4-Aryl Substituted 5-Trifluoromethoxyisatin-3-thiosemicarbazones.  

PubMed

A series of twenty one N4-aryl substituted 5-trifluoromethoxyisatin-3-thiosemicarbazones 3a-3u was synthesized by the reaction of trifluoromethoxyisatin 1 with different arylthiosemicarbazides 2 in aqueous ethanol (50%), containing a few drops of acetic acid. Their structures were established on the basis of analytical (CHN) and spectral (IR, 1H-NMR, EIMS) data. All the synthesized compounds were evaluated for their toxicity potential by a brine shrimp lethality bioassay. Ten compounds i.e., 3a, 3e, 3i-3l and 3n-3q proved to be active in this assay, displaying promising toxicity (LD50 = 1.11 × 10-5 M - 1.80 × 10-4 M). Amongst these, 3k, 3n and 3o were found to be the most active ones (LD50 = 1.11 × 10-5 M - 1.43 × 10-5 M). Compound 3k showed the highest activity with a LD50 value of 1.11 × 10-5 M and can, therefore, be used as a lead for further studies. Structure-activity relationship (SAR) studies revealed that the presence of strong inductively electron-attracting trifluoromethoxy substituent at position-5 of the isatin moiety played an important role in inducing or enhancing toxic potentiality of some of the synthesized compounds. PMID:25134761

Pervez, Humayun; Saira, Naveeda; Iqbal, Mohammad Saeed; Yaqub, Muhammad; Khan, Khalid Mohammed

2011-01-01

90

Ruthenium (II) complexes of thiosemicarbazone: synthesis, biosensor applications and evaluation as antimicrobial agents.  

PubMed

A conformationally rigid half-sandwich organoruthenium (II) complex [(?(6)-p-cymene)RuClTSC(N-S)]Cl, (1) and carbonyl complex [Ru(CO)Cl(PPh3)2TSC(N-S)] (2) have been synthesized from the reaction of [{(?(6)-p-cymene)RuCl}2(?-Cl)2] and [Ru(H)(Cl)(CO)(PPh3)3] with thiophene-2-carboxaldehyde thiosemicarbazon (TSC) respectively and both novel ruthenium (II) complexes have been characterized by elemental analysis, FT-IR and NMR spectroscopy. The peripheral TSC in the complexes acts as an electrochemical coupling unit providing the ability to carry out electrochemical deposition (ED) and to form an electro-deposited film on a graphite electrode surface. The biosensing applicability of complexes 1 and 2 was investigated by using glucose oxidase (GOx) as a model enzyme. Electrochemical measurements at -0.9V versus Ag/AgCl electrode by following the ED Ru(II) reduction/oxidation due to from the enzyme activity, in the presence of glucose substrate. The designed biosensor showed a very good linearity for 0.01-0.5mM glucose. The in vitro antimicrobial activities of complexes 1 and 2 were also investigated against nine bacterial strains and one fungus by the disc diffusion test method. No activity was observed against the Gram-negative strains and fungus, whereas complex 1 showed moderate antibacterial activities against Gram-positive bacterial strains. PMID:25280673

Yildirim, Hatice; Guler, Emine; Yavuz, Murat; Ozturk, Nurdan; Kose Yaman, Pelin; Subasi, Elif; Sahin, Elif; Timur, Suna

2014-11-01

91

2-Butyl-4-chloroimidazole based substituted piperazine-thiosemicarbazone hybrids as potent inhibitors of Mycobacterium tuberculosis.  

PubMed

Here a series of 2-butyl-4-chloroimidazole based substituted piperazine-thiosemicarbazone hybrids were designed by combining three different pharmacophoric fragments in single molecular architecture. 2-Butyl-4-chloro-1-(3-(4-substituted)piperazin-1-yl)propyl)-1H-imidazole-5-carbaldehydes (4a-p) prepared by reacting carboxaldehyde 2 with N-alkyl piperazines 3a-p which were condensed with thiosemicarbazine to give desired compounds 5a-p in very good yields. Among all sixteen compounds screened for in vitro antimycobacterial activity against Mycobacterium tuberculosis H37Rv (MTB), two compounds (E)-2-((2-butyl-4-chloro-1-(3-(4-(o-tolyl) piperazin-1-yl)propyl)-1H-imidazol-5-yl)methylene)hydrazinecarbothioamide 5e and (E)-2-((2-butyl-4-chloro-1-(3-(4-(2-methoxyphenyl)piperazin-1-yl)propyl)-1H-imidazol-5-yl)methylene) hydrazine carbothioamide 5f were found to be the most potent antitubercular agents (MIC: 3.13?g/mL) with low toxicity profile. PMID:25451998

Jallapally, Anvesh; Addla, Dinesh; Yogeeswari, Perumal; Sriram, Dharmarajan; Kantevari, Srinivas

2014-12-01

92

Study on the Interaction between Isatin-?-Thiosemicarbazone and Calf Thymus DNA by Spectroscopic Techniques  

PubMed Central

The interaction between isatin-?-thiosemicarbazone (IBT) and calf thymus DNA (CT-DNA) was investigated in physiological buffer (pH 7.4) using Neutral Red (NR) dye as a spectral probe by UV–Vis absorption and ?uorescence spectroscopy, as well as viscosity measurements. The IBT is stabilized by intercalation in the DNA (K [IBT –DNA] = 1.03×105 M?1), and displaces the NR dye from the NR–DNA complex. The binding constants Kf and number of binding sites (n?1) of IBT with DNA were obtained by fluorescence quenching method at different temperatures. Furthermore, the enthalpy and entropy of the reaction between IBT and CT-DNA showed that the reaction is enthalpy-favored and entropy-disfavored. The changes in the base stacking of CT-DNA upon the binding of IBT are reflected in the circular dichroic (CD) spectral studies. The viscosity increase of CT-DNA solution is another evidence to indicate that, IBT is able to be intercalated in the DNA base pairs. PMID:25561917

Pakravan, Parvaneh; Masoudian, Shahla

2015-01-01

93

Study on the Interaction between Isatin-?-Thiosemicarbazone and Calf Thymus DNA by Spectroscopic Techniques.  

PubMed

The interaction between isatin-?-thiosemicarbazone (IBT) and calf thymus DNA (CT-DNA) was investigated in physiological buffer (pH 7.4) using Neutral Red (NR) dye as a spectral probe by UV-Vis absorption and ?uorescence spectroscopy, as well as viscosity measurements. The IBT is stabilized by intercalation in the DNA (K [IBT -DNA] = 1.03×10(5) M(-1)), and displaces the NR dye from the NR-DNA complex. The binding constants Kf and number of binding sites (n?1) of IBT with DNA were obtained by fluorescence quenching method at different temperatures. Furthermore, the enthalpy and entropy of the reaction between IBT and CT-DNA showed that the reaction is enthalpy-favored and entropy-disfavored. The changes in the base stacking of CT-DNA upon the binding of IBT are reflected in the circular dichroic (CD) spectral studies. The viscosity increase of CT-DNA solution is another evidence to indicate that, IBT is able to be intercalated in the DNA base pairs. PMID:25561917

Pakravan, Parvaneh; Masoudian, Shahla

2015-01-01

94

Binuclear ruthenium(III) bis(thiosemicarbazone) complexes: Synthesis, spectral, electrochemical studies and catalytic oxidation of alcohol.  

PubMed

A new series of binuclear ruthenium(III) thiosemicarbazone complexes of general formula [(EPh3)2(X)2Ru-L-Ru(X)2(EPh3)2] (where E=P or As; X=Cl or Br; L=NS chelating bis(thiosemicarbazone ligands) has been synthesized and characterized by analytical and spectral (FT-IR, UV-Vis and EPR). IR spectra show that the thiosemicarbazones behave as monoanionic bidentate ligands coordinating through the azomethine nitrogen and thiolate sulphur. The electronic spectra of the complexes indicate that the presence of d-d and intense LMCT transitions in the visible region. The complexes are paramagnetic (low spin d(5)) in nature and all the complexes show rhombic distortion around the ruthenium ion with three different 'g' values (gx?gy?gz) at 77K. All the complexes are redox active and exhibit an irreversible metal centered redox processes (Ru(III)-Ru(III)/Ru(IV)-Ru(IV); Ru(III)-Ru(III)/Ru(II)-Ru(II)) within the potential range of 0.38-0.86V and -0.39 to -0.66 V respectively, versus Ag/AgCl. Further, the catalytic efficiency of one of the complexes [Ru2Cl2(AsPh3)4(L1)] (4) has been investigated in the case of oxidation of primary and secondary alcohols into their corresponding aldehydes and ketones in the presence of N-methylmorpholine-N-oxide(NMO) as co-oxidant. The formation of high valent Ru(V)O species is proposed as catalytic intermediate for the catalytic cycle. PMID:25498823

Mohamed Subarkhan, M; Ramesh, R

2015-03-01

95

Targeting triple negative breast cancer cells by N3-substituted 9,10-Phenanthrenequinone thiosemicarbazones and their metal complexes  

NASA Astrophysics Data System (ADS)

Novel N3-substituted 9,10-Phenanthrenequinone thiosemicarbazones and their copper, nickel and palladium complexes are structurally characterized and reported along with the single crystal X-ray structures of three ligands and one nickel complex. All compounds were evaluated for their antiproliferative potential against Triple Negative Breast Cancer (TNBC) cells which have poor prognosis and no effective drugs to treat with. All compounds exhibited antiproliferative activity against these cells. Among the metal complexes evaluated, redox active copper complexes were found to be more potent. The possible mechanism for such enhanced activity can be attributed to the generation of oxidative stress, which was amenable for targeting through metal complexation.

Afrasiabi, Zahra; Stovall, Preston; Finley, Kristen; Choudhury, Amitava; Barnes, Charles; Ahmad, Aamir; Sarkar, Fazlul; Vyas, Alok; Padhye, Subhash

2013-10-01

96

Synthesis and structure-activity evaluation of isatin-?-thiosemicarbazones with improved selective activity towards multidrug-resistant cells expressing P-glycoproteina  

PubMed Central

Cancer multidrug resistance (MDR) mediated by ATP-binding cassette (ABC) transporters presents a significant unresolved clinical challenge. One strategy to resolve MDR is to develop compounds that selectively kill cells over-expressing the efflux transporter P-glycoprotein (MDR1, P-gp, ABCB1). We have previously reported structure-activity studies based around the lead compound NSC73306 (1, 1-isatin-4-(4?-methoxyphenyl)-3-thiosemicarbazone, 4.3-fold selective). Here we sought to extend this work on MDR1-selective analogs by establishing whether 1 showed ‘robust’ activity against a range of cell lines expressing P-gp. We further aimed to synthesize and test analogs with varied substitution at the N4-position, and substitution around the N4-phenyl ring of isatin-?-thiosemicarbazones (IBTs), to identify compounds with increased MDR1-selectivity. Compound 1 demonstrated MDR1-selectivity against all P-gp-expressing cell lines examined. This selectivity was reversed by inhibitors of P-gp ATPase activity. Structural variation at the 4?-phenyl position of 1 yielded compounds of greater MDR1-selectivity. Two of these analogs, 1-isatin-4-(4?-nitrophenyl)-3-thiosemicarbazone (22, 8.3-fold selective) and 1-isatin-4-(4?-tert-butyl phenyl)-3-thiosemicarbazone (32, 14.8-fold selective), were selected for further testing, and were found to retain the activity profile of 1. These compounds are the most active IBTs identified to date. PMID:21721528

Hall, Matthew D.; Brimacombe, Kyle R.; Varonka, Matthew S.; Pluchino, Kristen M.; Monda, Julie K.; Li, Jiayang; Walsh, Martin J.; Boxer, Matthew B.; Warren, Timothy H.; Fales, Henry M.; Gottesman, Michael M.

2011-01-01

97

Improved antiparasitic activity by incorporation of organosilane entities into half-sandwich ruthenium(ii) and rhodium(iii) thiosemicarbazone complexes.  

PubMed

A series of ferrocenyl- and aryl-functionalised organosilane thiosemicarbazone compounds was obtained via a nucleophilic substitution reaction with an amine-terminated organosilane. The thiosemicarbazone (TSC) ligands were further reacted with either a ruthenium dimer [(?(6-i)PrC6H4Me)Ru(?-Cl)Cl]2 or a rhodium dimer [(Cp*)Rh(?-Cl)Cl]2 to yield a series of cationic mono- and binuclear complexes. The thiosemicarbazone ligands, as well as their metal complexes, were characterised using NMR and IR spectroscopy, and mass spectrometry. The molecular structure of the binuclear ruthenium(ii) complex was determined by single-crystal X-ray diffraction analysis. The thiosemicarbazones and their complexes were evaluated for their in vitro antiplasmodial activities against the chloroquine-sensitive (NF54) and chloroquine-resistant (Dd2) Plasmodium falciparum strains, displaying activities in the low micromolar range. Selected compounds were screened for potential ?-haematin inhibition activity, and it was found that two Rh(iii) complexes exhibited moderate to good inhibition. Furthermore, the compounds were screened for their antitrichomonal activities against the G3 Trichomonas vaginalis strain, revealing a higher percentage of growth inhibition for the ruthenium and rhodium complexes over their corresponding ligand. PMID:25559246

Adams, Muneebah; de Kock, Carmen; Smith, Peter J; Land, Kirkwood M; Liu, Nicole; Hopper, Melissa; Hsiao, Allyson; Burgoyne, Andrew R; Stringer, Tameryn; Meyer, Mervin; Wiesner, Lubbe; Chibale, Kelly; Smith, Gregory S

2015-01-20

98

Electrical Wiring of the Aldehyde Oxidoreductase PaoABC with a Polymer Containing Osmium Redox Centers: Biosensors for Benzaldehyde and GABA  

PubMed Central

Biosensors for the detection of benzaldehyde and ??aminobutyric acid (GABA) are reported using aldehyde oxidoreductase PaoABC from Escherichia coli immobilized in a polymer containing bound low potential osmium redox complexes. The electrically connected enzyme already electrooxidizes benzaldehyde at potentials below ?0.15 V (vs. Ag|AgCl, 1 M KCl). The pH-dependence of benzaldehyde oxidation can be strongly influenced by the ionic strength. The effect is similar with the soluble osmium redox complex and therefore indicates a clear electrostatic effect on the bioelectrocatalytic efficiency of PaoABC in the osmium containing redox polymer. At lower ionic strength, the pH-optimum is high and can be switched to low pH-values at high ionic strength. This offers biosensing at high and low pH-values. A “reagentless” biosensor has been formed with enzyme wired onto a screen-printed electrode in a flow cell device. The response time to addition of benzaldehyde is 30 s, and the measuring range is between 10–150 µM and the detection limit of 5 µM (signal to noise ratio 3:1) of benzaldehyde. The relative standard deviation in a series (n = 13) for 200 µM benzaldehyde is 1.9%. For the biosensor, a response to succinic semialdehyde was also identified. Based on this response and the ability to work at high pH a biosensor for GABA is proposed by coimmobilizing GABA-aminotransferase (GABA-T) and PaoABC in the osmium containing redox polymer. PMID:25587431

Badalyan, Artavazd; Dierich, Marlen; Stiba, Konstanze; Schwuchow, Viola; Leimkühler, Silke; Wollenberger, Ulla

2014-01-01

99

Evaluation of benzaldehyde derivatives from Morinda officinalis as anti-mite agents with dual function as acaricide and mite indicator  

PubMed Central

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by SFTS virus with 12–30% fatality rate. Despite severity of the disease, any medication or treatment for SFTS has not developed yet. One approach to prevent SFTS spreading is to control the arthropod vector carrying SFTS virus. We report that 2–methylbenzaldehyde analogues from M. officinalis have a dual function as acaricide against Dermatophagoides spp. and Haemaphysalis longicornis and indicator (color change) against Dermatophagoides spp. Based on the LD50 values, 2,4,5–trimethylbenzaldehyde (0.21, 0.19, and 0.68??g/cm3) had the highest fumigant activity against D. farinae, D. pteronyssinus, and H. longicornis, followed by 2,3–dimethylbenzaldehyde (0.46, 0.44, and 0.79??g/cm3), 2,4–dimethylbenzaldehyde (0.66, 0.59, and 0.95??g/cm3), 2,5–dimethylbenzaldehyde (0.65, 0.68, and 0.88??g/cm3), 2–methylbenzaldehyde (0.95, 0.87, and 1.28??g/cm3), 3–methylbenzaldehyde (0.99, 0.93, and 1.38??g/cm3), 4–methylbenzaldehyde (1.17, 1.15, and 3.67??g/cm3), and M. officinalis oil (7.05, 7.00, and 19.70??g/cm3). Furthermore, color alteration of Dermatophagoides spp. was shown to be induced, from colorless to dark brown, by the treatment of 2,3–dihydroxybenzaldehyde. These finding indicated that 2–methylbenzaldehyde analogues could be developed as functional agent associated with the arthropod vector of SFTS virus and allergen. PMID:25434408

Yang, Ji-Yeon; Kim, Min-Gi; Park, Jun-Hwan; Hong, Seong-Tshool; Lee, Hoi-Seon

2014-01-01

100

Effects of terminal dimethylation and metal coordination of proline-2-formylpyridine thiosemicarbazone hybrids on lipophilicity, antiproliferative activity, and hR2 RNR inhibition.  

PubMed

The nickel(II), copper(II), and zinc(II) complexes of the proline-thiosemicarbazone hybrids 3-methyl-(S)-pyrrolidine-2-carboxylate-2-formylpyridine thiosemicarbazone (L-Pro-FTSC or (S)-H2L(1)) and 3-methyl-(R)-pyrrolidine-2-carboxylate-2-formylpyridine thiosemicarbazone (D-Pro-FTSC or (R)-H2L(1)), as well as 3-methyl-(S)-pyrrolidine-2-carboxylate-2-formylpyridine 4,4-dimethyl-thiosemicarbazone (dm-L-Pro-FTSC or (S)-H2L(2)), namely, [Ni(L-Pro-FTSC-2H)]2 (1), [Ni(D-Pro-FTSC-2H)]2 (2), [Ni(dm-L-Pro-FTSC-2H)]2 (3), [Cu(dm-L-Pro-FTSC-2H)] (6), [Zn(L-Pro-FTSC-2H)] (7), and [Zn(D-Pro-FTSC-2H)] (8), in addition to two previously reported, [Cu(L-Pro-FTSC-2H)] (4), [Cu(D-Pro-FTSC-2H)] (5), were synthesized and characterized by elemental analysis, one- and two-dimensional (1)H and (13)C NMR spectroscopy, circular dichroism, UV-vis, and electrospray ionization mass spectrometry. Compounds 1-3, 6, and 7 were also studied by single-crystal X-ray diffraction. Magnetic properties and solid-state high-field electron paramagnetic resonance spectra of 2 over the range of 50-420 GHz were investigated. The complex formation processes of L-Pro-FTSC with nickel(II) and zinc(II) were studied in aqueous solution due to the excellent water solubility of the complexes via pH potentiometry, UV-vis, and (1)H NMR spectroscopy. The results of the antiproliferative activity in vitro showed that dimethylation improves the cytotoxicity and hR2 RNR inhibition. Therefore, introduction of more lipophilic groups into thiosemicarbazone-proline backbone becomes an option for the synthesis of more efficient cytotoxic agents of this family of compounds. PMID:25391085

Bacher, Felix; Dömötör, Orsolya; Kaltenbrunner, Maria; Mojovi?, Miloš; Popovi?-Bijeli?, Ana; Gräslund, Astrid; Ozarowski, Andrew; Filipovic, Lana; Radulovi?, Sinisa; Enyedy, Éva A; Arion, Vladimir B

2014-12-01

101

Lewis acid-catalyzed redox-neutral amination of 2-(3-pyrroline-1-yl)benzaldehydes via intramolecular [1,5]-hydride shift/isomerization reaction  

PubMed Central

Summary Lewis acid-catalyzed redox-neutral amination of 2-(3-pyrroline-1-yl)benzaldehydes via intramolcular [1,5]-hydride shift/isomerization reaction has been realized, using the inherent reducing power of 3-pyrrolines. A series of N-arylpyrrole containing amines are obtained in high yields. PMID:25550755

Jiang, Chun-Huan; Lei, Xiantao; Zhen, Le; Du, Hong-Jin; Wen, Xiaoan

2014-01-01

102

Operational concept for the improved synthesis of (R)-3,3'-furoin and related hydrophobic compounds with benzaldehyde lyase.  

PubMed

Biphasic reaction systems for enzyme catalysis are an elegant way to overcome limited solubility and stability of reactants and facilitate continuous processes. However, many synthetically useful enzymes are not stable in biphasic systems of water and organic solvent. The entrapment in polymer beads of polyvinyl alcohol has been shown to enable the stable operation of enzymes unstable in conventional biphasic reaction systems. We report the extension of this concept to continuous operation in a fluidised bed reactor. The enzyme benzaldehyde lyase was used for the continuous synthesis of enantiopure (R)-3,3'-furoin. The results show enhanced stability with half-life times under operation conditions of more than 100 h, as well as superior enzyme utilisation in terms of productivity. Furthermore, racemisation and oxidation of the product could be successfully prevented under the non-aqueous and inert reaction conditions. PMID:16892292

Ansorge-Schumacher, Marion B; Greiner, Lasse; Schroeper, Florian; Mirtschin, Sebastian; Hischer, Tanja

2006-05-01

103

Nickel(II) Complex of Polyhydroxybenzaldehyde N4-Thiosemicarbazone Exhibits Anti-Inflammatory Activity by Inhibiting NF-?B Transactivation  

PubMed Central

Background The biological properties of thiosemicarbazone have been widely reported. The incorporation of some transition metals such as Fe, Ni and Cu to thiosemicarbazone complexes is known to enhance its biological effects. In this study, we incorporated nickel(II) ions into thiosemicarbazone with N4-substitution groups H3L (H; H3L1, CH3; H3L2, C6H5; H3L3 and C2H5; H3L4) and examined its potential anti-inflammatory activity. Methodology/Principal Findings Four ligands (1–4) and their respective nickel-containing complexes (5–8) were synthesized and characterized. The compounds synthesized were tested for their effects on NF-?B nuclear translocation, pro-inflammatory cytokines secretion and NF-?B transactivation activity. The active compound was further evaluated on its ability to suppress carrageenan-induced acute inflammation in vivo. A potential binding target of the active compound was also predicted by molecular docking analysis. Conclusions/Significance Among all synthesized compounds tested, we found that complex [Ni(H2L1)(PPh3)]Cl (5) (complex 5), potently inhibited I?B? degradation and NF-?B p65 nuclear translocation in LPS-stimulated RAW264.7 cells as well as TNF?-stimulated HeLa S3 cells. In addition, complex 5 significantly down-regulated LPS- or TNF?-induced transcription of NF-?B target genes, including genes that encode the pro-inflammatory cytokines TNF?, IFN? and IL6. Luciferase reporter assays confirmed that complex 5 inhibited the transactivation activity of NF-?B. Furthermore, the anti-inflammatory effect of complex 5 was also supported by its suppressive effect on carrageenan-induced paw edema formation in wild type C57BL/6 mice. Interestingly, molecular docking study showed that complex 5 potentially interact with the active site of IKK?. Taken together, we suggest complex 5 as a novel NF-?B inhibitor with potent anti-inflammatory effects. PMID:24977407

Loh, Sheng Wei; Looi, Chung Yeng; Hassandarvish, Pouya; Phan, Alicia Yi Ling; Wong, Won Fen; Wang, Hao; Paterson, Ian C.; Ea, Chee Kwee; Mustafa, Mohd Rais; Maah, Mohd Jamil

2014-01-01

104

Synthesis, antioxidant activities of the nickel(II), iron(III) and oxovanadium(IV) complexes with N2O2 chelating thiosemicarbazones.  

PubMed

The nickel(II), iron(III) and oxovanadium(IV) complexes of the N2O2 chelating thiosemicarbazones were synthesized using 4-hydroxysalicyladehyde-S-methylthiosemicarbazone and R1-substitute-salicylaldehyde (R1: 4-OH, H) in the presence of Ni(II), Fe(III), VO(IV) ions by the template reaction. The structures of the thiosemicarbazone complexes were characterized by FT-IR, (1)H NMR, elemental, ESI-MS and APCI-MS analysis. The synthesized compounds were screened for their antioxidant capacity by using the cupric reducing antioxidant capacity (CUPRAC) method. Trolox equivalent antioxidant capacity (TEAC) of iron(III) complex, 1c, was measured to be higher than that of the other complexes. Other parameters of antioxidant activity (scavenging effects on •OH, O2(•-) and H2O2) of these compounds were also determined. All the compounds have shown encouraging ROS scavenging activities. PMID:24656797

Bal-Demirci, Tülay; Sahin, Musa; Ozyürek, Mustafa; Kondakç?, Esin; Ulküseven, Bahri

2014-05-21

105

Synthesis, antioxidant activities of the nickel(II), iron(III) and oxovanadium(IV) complexes with N2O2 chelating thiosemicarbazones  

NASA Astrophysics Data System (ADS)

The nickel(II), iron(III) and oxovanadium(IV) complexes of the N2O2 chelating thiosemicarbazones were synthesized using 4-hydroxysalicyladehyde-S-methylthiosemicarbazone and R1-substitute-salicylaldehyde (R1: 4-OH, H) in the presence of Ni(II), Fe(III), VO(IV) ions by the template reaction. The structures of the thiosemicarbazone complexes were characterized by FT-IR, 1H NMR, elemental, ESI-MS and APCI-MS analysis. The synthesized compounds were screened for their antioxidant capacity by using the cupric reducing antioxidant capacity (CUPRAC) method. Trolox equivalent antioxidant capacity (TEAC) of iron(III) complex, 1c, was measured to be higher than that of the other complexes. Other parameters of antioxidant activity (scavenging effects on rad OH, O2rad - and H2O2) of these compounds were also determined. All the compounds have shown encouraging ROS scavenging activities.

Bal-Demirci, Tülay; ?ahin, Musa; Özyürek, Mustafa; Kondakç?, Esin; Ülküseven, Bahri

106

Crystal structures of 5-Bromo-2-hydroxybenzaldehyde, 2-hydroxy-3-methoxybenzaldehyde, and 2-hydroxynaphthalene-1-carbaldehyde 4-(2-pyridyl) thiosemicarbazones  

NASA Astrophysics Data System (ADS)

5-Bromo-2-hydroxybenzaldehyde, 2-hydroxy-3-methoxybenzaldehyde, and 2-hydroxynaphthalene-1-carbaldehyde 4-(2-pyridyl) thiosemicarbazones ( I-III, respectively) were synthesized and their crystal structures were determined by X-ray diffraction. All these molecules are almost planar. The presence of bulky substituents at the terminal nitrogen atoms of these molecules does not lead to changes in the conformation of the thiosemicarbazide moiety. Depending on the nature of substituents in the phenol rings, the crystals are composed of either centrosymmetric dimers ( I) or infinite chains ( II and III). In the concentration range of 10-5-10-7 mol/L, thiosemicarbazones I-III selectively inhibit the growth of human myeloid leukemia HL60 cells.

Chumakov, Yu. M.; Petrenko, P. A.; Codita, T. B.; Tsapkov, V. I.; Poirier, D.; Gulea, A. P.

2014-03-01

107

Preconcentration of Some Trace Metal Ions from Drinking and Tap Water Samples by Sorption on Amberlite XAD?4 after Complexation with Di?2?Pyridyl Ketone Thiosemicarbazone  

Microsoft Academic Search

A method was established for enrichment of trace levels of Co(II), Ni(II), Fe(II), and Cu(II) ions in aqueous solutions. These metals were quantitatively retained on an Amberlite XAD?4 column, after complexation with di?2?pyridyl ketone thiosemicarbazone (DPKT). After elution with 1 M HNO3 in acetone, concentration of metals were measured by atomic absorption spectrometry. The effect of major cations of drinking and

Bürge A?ç?; Güzin Alpdo?an; S?d?ka Sungur

2006-01-01

108

Synthesis, Spectroscopic and Physicochemical Characterization and Biological Activity of Co(II) and Ni(II) Coordination Compounds with 4-Aminoantipyrine Thiosemicarbazone  

PubMed Central

We describe the synthesis and characterization of cobalt(II) and nickel(II) coordination compounds of 4[N-(furan-2’-aldimine)amino]antipyrine thiosemicarbazone (FFAAPTS) and 4[N-(4'-nitrobenzalidene) amino]antipyrine thiosemicarbazone (4'-NO2BAAPTS). All the isolated compounds have the general composition MX2(L)(H2O) (M = Co2+ or Ni2+; X = Cl, Br, NO3, NCS or CH3COO; L = FFAAPTS or 4'-NO2BAAPTS) and M(ClO4)2(L)2 (M = Co2+ or Ni2+; L = FFAAPTS or 4'-NO2BAAPTS). Infrared spectral studies indicate that both the thiosemicarbazones coordinate in their neutral form and they act as {N,N,S} tridentate chelating ligands. Room temperature magnetic measurements and electronic spectral studies suggest the distorted octahedral geometries of the prepared complexes. Thermogravimetric studies are also reported and the possible structures of the complexes are proposed. Antibacterial and antifungal properties of these metal-coordination compounds have also been studied. PMID:18365104

2005-01-01

109

Suitable combination of promoter and micellar catalyst for kilo fold rate acceleration on benzaldehyde to benzoic acid conversion in aqueous media at room temperature: a kinetic approach.  

PubMed

The kinetics of oxidation of benzaldehyde by chromic acid in aqueous and aqueous surfactant (sodium dodecyl sulfate, SDS, alkyl phenyl polyethylene glycol, Triton X-100 and N-cetylpyridinium chloride, CPC) media have been investigated in the presence of promoter at 303 K. The pseudo-first-order rate constants (kobs) were determined from a logarithmic plot of absorbance as a function time. The rate constants were found to increase with introduction of heteroaromatic nitrogen base promoters such as Picolinic acid (PA), 2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen). The product benzoic acid has been characterized by conventional melting point experiment, NMR, HRMS and FTIR spectral analysis. The mechanism of both unpromoted and promoted reaction path has been proposed for the reaction. In presence of the anionic surfactant SDS, cationic surfactant CPC and neutral surfactant TX-100 the reaction can undergo simultaneously in both aqueous and micellar phase with an enhanced rate of oxidation in the micellar phase. Both SDS and TX-100 produce normal micellar effect whereas CPC produce reverse micellar effect in the presence of benzaldehyde. The observed net enhancement of rate effects has been explained by considering the hydrophobic and electrostatic interaction between the surfactants and reactants. SDS and bipy combination is the suitable one for benzaldehyde oxidation. PMID:23501718

Ghosh, Aniruddha; Saha, Rumpa; Ghosh, Sumanta K; Mukherjee, Kakali; Saha, Bidyut

2013-05-15

110

Suitable combination of promoter and micellar catalyst for kilo fold rate acceleration on benzaldehyde to benzoic acid conversion in aqueous media at room temperature: A kinetic approach  

NASA Astrophysics Data System (ADS)

The kinetics of oxidation of benzaldehyde by chromic acid in aqueous and aqueous surfactant (sodium dodecyl sulfate, SDS, alkyl phenyl polyethylene glycol, Triton X-100 and N-cetylpyridinium chloride, CPC) media have been investigated in the presence of promoter at 303 K. The pseudo-first-order rate constants (kobs) were determined from a logarithmic plot of absorbance as a function time. The rate constants were found to increase with introduction of heteroaromatic nitrogen base promoters such as Picolinic acid (PA), 2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen). The product benzoic acid has been characterized by conventional melting point experiment, NMR, HRMS and FTIR spectral analysis. The mechanism of both unpromoted and promoted reaction path has been proposed for the reaction. In presence of the anionic surfactant SDS, cationic surfactant CPC and neutral surfactant TX-100 the reaction can undergo simultaneously in both aqueous and micellar phase with an enhanced rate of oxidation in the micellar phase. Both SDS and TX-100 produce normal micellar effect whereas CPC produce reverse micellar effect in the presence of benzaldehyde. The observed net enhancement of rate effects has been explained by considering the hydrophobic and electrostatic interaction between the surfactants and reactants. SDS and bipy combination is the suitable one for benzaldehyde oxidation.

Ghosh, Aniruddha; Saha, Rumpa; Ghosh, Sumanta K.; Mukherjee, Kakali; Saha, Bidyut

2013-05-01

111

Using heavy atom rare gas matrix to control the reactivity of 4-methoxybenzaldehyde: A comparison with benzaldehyde  

SciTech Connect

Different patterns of photochemical behavior were observed for 4-methoxybenzaldehyde (p-anisaldehyde) isolated in xenon and in argon matrices. Monomers of the compound isolated in solid Xe decarbonylate upon middle ultraviolet irradiation, yielding methoxybenzene (anisole), and CO. On the other hand, p-anisaldehyde isolated in an Ar matrix and subjected to identical irradiation, predominantly isomerizes to the closed-ring isomeric ketene (4-methoxycyclohexa-2,4-dien-1-ylidene) methanone. Experimental detection of a closed-ring ketene photoproduct, generated from an aromatic aldehyde, constitutes a rare observation. The difference between the patterns of photochemical transformations of p-anisaldehyde isolated in argon and xenon environments can be attributed to the external heavy-atom effect, where xenon enhances the rate of intersystem crossing from the singlet to the triplet manifold in which decarbonylation (via p-methoxybenzoyl radical) takes place. The parent compound, benzaldehyde, decarbonylates (to benzene + CO) when subjected to middle ultraviolet irradiation in both argon and xenon matrices. This demonstrates the role of the methoxy p-anisaldehyde substituent in activation of the reaction channel leading to the formation of the ketene photoproduct.

Kus, Nihal [Department of Chemistry, University of Coimbra, 3004-535 Coimbra (Portugal); Department of Physics, Anadolu University, 26470 Eskisehir (Turkey); Sharma, Archna; Reva, Igor; Fausto, Rui [Department of Chemistry, University of Coimbra, 3004-535 Coimbra (Portugal); Lapinski, Leszek [Institute of Physics, Polish Academy of Sciences, Warsaw (Poland)

2012-04-14

112

Synthesis and screening of biologically significant 5-hydroxy isatin derivatives for antioxidant activity.  

PubMed

In the present work, some new 5-Hydroxyindole 3-thiosemicarbazone 2-ones and 5-[2(3)-dialkylaminoalkoxy] Indole 3-hydrazone 2-ones were prepared from 5-hydroxy isatin. The structures of the products were characterized by IR, NMR, and MASS Spectral studies. All the compounds were examined for antioxidant activity by using 1,1-diphenyl-2-picryl-hydrazyl and hydrogen peroxide (H2O2), and the total antioxidant capacity by a phosphomolybdenum assay. In general, the derivatives were found to exhibit antioxidant activity. Further, the compounds with dialkyl amino alkoxy at the C5 position demonstrated significant antioxidant activity. PMID:25416982

Swathi, Konda; Sarangapani, Manda

2015-01-01

113

Synthesis, spectroscopic, anticancer and antibacterial studies of Ni(II) and Cu(II) complexes with 2-carboxybenzaldehyde thiosemicarbazone.  

PubMed

Ni(II) and Cu(II) complexes of 2-carboxybenzaldehyde thiosemicarbazone (L) were synthesized and investigated by their spectral and analytical data. These newly synthesized complexes have a composition of M(L)X(H2O)2 (where M=Ni(II), Cu(II) and X=Cl(-), NO3(-), CH3COO(-)) and (L) is the tridentate Schiff base ligand. The ligand and its complexes have been characterized on the basis of analytical, molar conductivity, magnetic susceptibility measurements, FT-IR, ESR, (1)H NMR and electronic spectral analysis. All the compounds were non-electrolytic in nature. On the basis of spectral studies an octahedral geometry has been assigned for Ni(II) and a tetragonal geometry for Cu(II) complexes. The ligand and its metal complexes were screened for their anticancer studies against human breast cancer cell lines MCF-7 and calculated minimum inhibitory concentration and also for antibacterial activity using Kirby-Bauer single disk susceptibility test. PMID:24747857

Chandra, Sulekh; Vandana

2014-08-14

114

Synthesis, spectroscopic, anticancer and antibacterial studies of Ni(II) and Cu(II) complexes with 2-carboxybenzaldehyde thiosemicarbazone  

NASA Astrophysics Data System (ADS)

Ni(II) and Cu(II) complexes of 2-carboxybenzaldehyde thiosemicarbazone (L) were synthesized and investigated by their spectral and analytical data. These newly synthesized complexes have a composition of M(L)X(H2O)2 (where M = Ni(II), Cu(II) and X = Cl-, NO3-, CH3COO-) and (L) is the tridentate Schiff base ligand. The ligand and its complexes have been characterized on the basis of analytical, molar conductivity, magnetic susceptibility measurements, FT-IR, ESR, 1H NMR and electronic spectral analysis. All the compounds were non-electrolytic in nature. On the basis of spectral studies an octahedral geometry has been assigned for Ni(II) and a tetragonal geometry for Cu(II) complexes. The ligand and its metal complexes were screened for their anticancer studies against human breast cancer cell lines MCF-7 and calculated minimum inhibitory concentration and also for antibacterial activity using Kirby-Bauer single disk susceptibility test.

Chandra, Sulekh; Vandana

2014-08-01

115

Diorganotin Complexes of a Thiosemicarbazone, Synthesis: Properties, X-Ray Crystal Structure, and Antiproliferative Activity of Diorganotin Complexes  

PubMed Central

The synthesis and spectral characterization of novel diorganotin complexes with 3-hydroxypyridine-2-carbaldehyde thiosemicarbazone, H2L(1), [SnMe2(L)] (2), [SnBu2(L)] (3), and [SnPh2(L)] (4) are reported. The single-crystal X-ray structure of complex [SnPh2(L)(DMSO)] (5) shows that the ligand is doubly deprotonated and is coordinated as tridentate ligand. The six coordination number is completed by two carbon atoms of phenyl groups. There are two similar monomers 5a (Sn1) and 5b (Sn51) in the asymmetric unit. The monomers 5a and 5b are linked through intermolecular hydrogen bonds of N–H–O and C–H–S type. C–H ? ?, intermolecular interactions, intra- and intermolecular hydrogen bonds stabilize this structure and leads to aggregation and a supramolecular assembly. The IR and NMR (1H, 13C and 119Sn) spectroscopic data of the complexes are reported. The in vitro cytotoxic activity has been evaluated against the cells of three human cancer cell lines: MCF-7 (human breast cancer cell line), T-24 (bladder cancer cell line), A-549 (nonsmall cell lung carcinoma) and a mouse L-929 (a fibroblast-like cell line cloned from strain L). Compounds 1, 3, and 4 were found active against all four cell lines. Selectivity was observed for complexes 3 and 4 which were found especially active against MCF-7 and T-24 cancer cell lines. PMID:20689713

Wiecek, Joanna; Kovala-Demertzi, Dimitra; Ciunik, Zbigniew; Zervou, Maria; Demertzis, Mavroudis A.

2010-01-01

116

Copper(II) and nickel(II) complexes of benzyloxybenzaldehyde-4-phenyl-3-thiosemicarbazone: Synthesis, characterization and biological activity  

NASA Astrophysics Data System (ADS)

Benzyloxybenzaldehyde-4-phenyl-3-thiosemicarbazone ligand (L) has been synthesized from benzyloxybenzaldehyde and 4-phenyl-3-thiosemicarbazide. Complexes of this ligand with chlorides of Cu(II) and Ni(II) have been prepared. The structure of the ligand (L) is proposed based on elemental analysis, IR and 1H NMR spectra. Its complexes with Cu(II) and Ni(II) ions are characterized from the studies of electronic as well as EPR spectra. On the basis of electronic and EPR studies, rhombically distorted octahedral structure has been proposed for Cu(II) complex while the Ni(II) complex has been found to acquire an octahedral structure. The ligand and their metal complexes have been tested in vitro for their biological effects. Their antibacterial activities against Gram-negative bacteria ( Escherichia coli and Klebsiella pneumoniae) and Gram-positive bacteria ( Staphylococcus aureus and Bacillus subtilis) have been investigated. The prepared metal complexes exhibit higher antibacterial activities than the parent ligand. The in vitro antioxidant activity of free ligand and its metal(II) complexes have also been investigated and the results however reveal that the ligand exhibits greater antioxidant activity than its complexes.

Prathima, B.; Subba Rao, Y.; Adinarayana Reddy, S.; Reddy, Y. P.; Varada Reddy, A.

2010-09-01

117

Synthesis, Crystal Structure, and Second-Order Optical Nonlinearity of Bis(2-chlorobenzaldehyde thiosemicarbazone)cadmium Halides (CdL(2)X(2); X = Br, I).  

PubMed

The new Schiff base ligand 2-chlorobenzaldehyde thiosemicarbazone (L, 1) has been synthesized and characterized by spectral techniques and single-crystal X-ray analysis. Crystals of 1 are monoclinic, space group P2(1)/n with a = 12.964(4) Å, b = 5.131(5) Å, c = 4.970(1) Å, beta = 94.32(2) degrees, and Z = 4. The thiosemicarbazone moiety adopts a configuration with N(1) cis to N(3) and places the E configuration about both the bonds C(1)-N(2) and C(2)-N(3). The monodentate behavior of the neutral ligand (L) has been investigated in two cadmium halides CdL(2) Br(2) (2) and CdL(2)I(2) (3). Compound 2 crystallizes in space group Cc witha = 8.175(1) Å, b = 14.176(1) Å, c = 21.073(1) Å, beta = 94.02(1) degrees, and Z = 4. Compound 3 crystallizes in space group P&onemacr; with a = 10.9577(1) Å, b = 16.174(1) Å, c = 7.878(1) Å, alpha = 100.50(1) degrees, beta = 109.39(1) degrees, gamma = 83.67(1) degrees, and Z = 2. The coordination geometry about the cadmium(II) atom in compound 2 conforms to a tetrahedral configuration with two sulfur atoms from two unequivalent neutral ligands and two bromide atoms. Whereas the coordination geometry about the cadmium(II) atom in compound 3 is (4 + 1) distorted trigonal bipyramidal with two iodide atoms and one sulfur atom in the equatorial plane, the other thiosemicarbazone sulfur and the iodide atom I(1a) of an adjacent moiety occupy the axial positions. Compound 2 exhibits powder SHG efficiencies ca. 20 times that of urea, whereas compound 3 does not exhibit any SHG efficiency. Theory and experiment suggested that intermolecular contact is the main factor controlling the SHG efficiencies of compounds. PMID:11669693

Tian Yp, Yu-peng; Duan Cy, Chun-ying; Zhao Cy, Cun-yuan; You Xz, Xiao-zeng; Mak, Thomas C. W.; Zhang Zy, Ze-ying

1997-03-12

118

Iron and Cobalt Complexes of 2,6-Diacetylpyridine-bis(R-thiosemicarbazone) (R=H, phenyl) Showing Unprecedented Ligand Deviation from Planarity  

PubMed Central

The syntheses, characterization, and single-crystal X-ray crystal structures are reported for four complexes of iron and cobalt with the pentadentate ligands, 2,6-diacetylpyridinebis(thiosemicarbazone) (H2L1) and 2,6-diacetylpyridinebis-(phenylthiosemicarbazone) (H2L2), including a cobalt dimer displaying a deviation from planarity which is unprecedented for this class of ligands and allows the ligand to occupy five positions of a pseudo-octahedral coordination sphere. This dimer reacts with KCN to produce a mononuclear complex of relevance to the active site of cobalt nitrile hydratase. PMID:20161238

Panja, Anangamohan; Campana, Charles; Leavitt, Christopher; Van Stipdonk, Michael J.; Eichhorn, David M.

2009-01-01

119

Synthesis, characterization and antimicrobial activity of a Zn(II) complex with 1-(1H-benzoimidazol-2-yl)-ethanone thiosemicarbazone  

Microsoft Academic Search

A new Zn(II) complex with 1-(1H-benzoimidazol-2-yl)-ethanone thiosemicarbazone [Zn(NO3)(H2O)(C10H11N5S)]NO3 was prepared and characterized by elemental analyses, FT-IR, H NMR spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction (XRD), and single-crystal X-ray diffraction analysis. The coordination geometry of the pentacoordinated zinc is a distorted square pyramid. The antimicrobial activity of the complex was evaluated using a broth micro-dilution method against a panel of human

Mehmet Poyraz; Musa Sar?; Ayse Güney; Fatih Demirci; Seref Demirayak; Ertan ?ahin

2008-01-01

120

Synthesis, crystal structure and biological activity of 1-(1 H-benzoimidazol-2-yl)-ethanone thiosemicarbazone and its cobalt complex  

Microsoft Academic Search

1-(1H-Benzoimidazol-2-yl)-ethanone thiosemicarbazone (H2L) (1) was obtained by the condensation reaction of 2-acetylbenzimidazole, thiosemicarbazide and acetic acid in ethanol. The novel cobalt(III) complex [Co(L)(HL)] 2 was prepared by the direct reaction of CoCl2·6H2O with the ligand H2L. The reaction products were characterized by elemental analysis, thermogravimetric analysis (TGA), FT-IR and mass spectrometry for H2L, and magnetic measurement for the Co(III) complex.

Mehmet Poyraz; Musa Sari; Fatih Demirci; Muberra Kosar; Seref Demirayak; Orhan Büyükgüngör

2008-01-01

121

Potent 5-nitrofuran derivatives inhibitors of Trypanosoma cruzi growth: Electrochemical, spectroscopic and biological studies  

NASA Astrophysics Data System (ADS)

Cyclic voltammetry and electron spin resonance techniques were used in the investigation of several potential antiprotozoal containing thiosemicarbazone and carbamate nitrofurans. In the electrochemical behaviour, a self-protonation process involving the nitro group was observed. The reactivity of the nitro anion radical for these derivatives with glutathione, a biological relevant thiol, was also studied in means of cyclic voltammetry. These studies demonstrated that glutathione could react with radical species from 5-nitrofuryl system. Furthermore, from the voltammetric results, some parameters of biological significance as E71 (indicative of the biological nitro anion radical formation), and K (thermodynamic indicator the of oxygen redox cycling) have been calculated. We also evaluated the stability of the nitro anion radical in terms of the dimerization constant ( kd). The nitrofuran-free radicals from cyclic voltammetry were characterized by electron spin resonance. A clear dependence between both the thiosemicarbazone or carbamate substructure and the length of the linker, furyl- or furylpropenyl-spacer, and the delocalization of the unpaired electron was observed. Through of biological assays we obtained important parameters that account for the selective anti-trypanosomal activity of these derivatives. The trypomastigote viability study showed that all derivatives are as active as in the epimastigote form of the parasite in a doses dependent manner.

Maria Aravena, C.; Claudio Olea, A.; Cerecetto, Hugo; González, Mercedes; Maya, Juan Diego; Rodríguez-Becerra, Jorge

2011-07-01

122

Potent 5-nitrofuran derivatives inhibitors of Trypanosoma cruzi growth: electrochemical, spectroscopic and biological studies.  

PubMed

Cyclic voltammetry and electron spin resonance techniques were used in the investigation of several potential antiprotozoal containing thiosemicarbazone and carbamate nitrofurans. In the electrochemical behaviour, a self-protonation process involving the nitro group was observed. The reactivity of the nitro anion radical for these derivatives with glutathione, a biological relevant thiol, was also studied in means of cyclic voltammetry. These studies demonstrated that glutathione could react with radical species from 5-nitrofuryl system. Furthermore, from the voltammetric results, some parameters of biological significance as E(7)(1) (indicative of the biological nitro anion radical formation), and [Formula: see text] (thermodynamic indicator the of oxygen redox cycling) have been calculated. We also evaluated the stability of the nitro anion radical in terms of the dimerization constant (k(d)). The nitrofuran-free radicals from cyclic voltammetry were characterized by electron spin resonance. A clear dependence between both the thiosemicarbazone or carbamate substructure and the length of the linker, furyl- or furylpropenyl-spacer, and the delocalization of the unpaired electron was observed. Through of biological assays we obtained important parameters that account for the selective anti-trypanosomal activity of these derivatives. The trypomastigote viability study showed that all derivatives are as active as in the epimastigote form of the parasite in a doses dependent manner. PMID:21470905

Aravena, C Maria; Olea, A Claudio; Cerecetto, Hugo; González, Mercedes; Maya, Juan Diego; Rodríguez-Becerra, Jorge

2011-07-01

123

Density, Viscosity, Sound Speed, and Thermoacoustical Parameters of Benzaldehyde with Chlorobenzene or Nitrobenzene at 303.15 K, 308.15 K, and 313.15 K  

NASA Astrophysics Data System (ADS)

The values of the density, viscosity, and speed of sound for binary liquid mixtures of benzaldehyde with chlorobenzene or nitrobenzene have been measured over the entire range of composition at (303.15, 308.15, and 313.15) K. These values have been used to calculate the excess molar volume (), and excess free volume (). McAllister's three-body interaction model is used for correlating the kinematic viscosity of binary mixtures. The thermophysical properties (density, viscosity, and ultrasonic velocity) under study were fit to the Jouyban-Acree model.

Lavanya, T. G.; Saravanakumar, K.; Baskaran, R.; Kubendran, T. R.

2013-07-01

124

Synthesis, X-ray crystal structure, DNA binding, antioxidant and cytotoxicity studies of Ni(ii) and Pd(ii) thiosemicarbazone complexes.  

PubMed

New complexes, [Ni(HL)(PPh(3))]Cl (1), [Pd(L)(PPh(3))](2), and [Pd(L)(AsPh(3))](3), were synthesized from the reactions of 4-chloro-5-methyl-salicylaldehyde thiosemicarbazone [H(2)L] with [NiCl(2)(PPh(3))(2)], [PdCl(2)(PPh(3))(2)] and [PdCl(2)(AsPh(3))(2)]. They were characterized by IR, electronic, (1)H-NMR spectral data. Further, the structures of the complexes have been determined by single crystal X-ray diffraction. While the thiosemicarbazone coordinated as binegative tridentate (ONS) in complexes 2 and 3, it is coordinated as mono negative tridentate (ONS) in 1. The interactions of the new complexes with calf thymus DNA was examined by absorption and emission spectra, and viscosity measurements. Moreover, the antioxidant properties of the new complexes have also been tested against DPPH radical in which complex 1 exhibited better activity than that of the other two complexes 2 and 3. The in vitro cytotoxicity of complexes 1-3 against A549 and HepG2 cell lines was assayed, and the new complexes exhibited higher cytotoxic activity with lower IC(50) values indicating their efficiency in killing the cancer cells even at very low concentrations. PMID:22101384

Ramachandran, Eswaran; Kalaivani, Palaniappan; Prabhakaran, Rathinasabapathi; Rath, Nigam P; Brinda, Selvaraj; Poornima, Paramasivan; Padma, Viswanatha Vijaya; Natarajan, Karuppannan

2012-02-01

125

Characterization of the anticancer effects of S115, a novel heteroaromatic thiosemicarbazone compound, in vitro and in vivo  

PubMed Central

Aim: To investigate the anticancer effects of S115, a novel heteroaromatic thiosemicarbazone compound in vitro and in vivo. Methods: The anti-proliferative action of S115 was analyzed in 12 human and mouse cancer cell lines using MTT assay. Autograft and xenograft cancer models were made by subcutaneous inoculation of cancer cells into mice or nude mice. The mice were orally treated with S115 (2, 8, 32 mg·kg?1·d?1) for 7 d, and the tumor size was measured every 3 d. Cell apoptosis and cell cycle distribution were examined using flow cytometry, gene expression profile analyses, Western blots and RT-PCR. Results: The IC50 values of S115 against 12 human and mouse cancer cell lines ranged from 0.3 to 6.6 ?mol/L. The tumor growth inhibition rate caused by oral administration of S115 (32 mg·kg?1·d?1) were 89.7%, 81.7%, 78.4% and 77.8%, respectively, in mouse model of B16 melanoma, mouse model of Colon26 colon cancer, nude mouse model of A549 lung cancer and nude mouse model of SK-OV-3 ovarian cancer. Furthermore, oral administration of S115 (7.5 mg·kg?1·d?1) synergistically enhanced the anticancer effects of cyclophosphamide, cisplatin, or 5-fluorouracil in mouse model of S180 sarcoma. Treatment of A549 human lung cancer cells with S115 (1.5 ?mol/L) induced G0/G1 cell cycle arrest, and increased apoptosis. Furthermore, S115 downregulated the level of ubiquitin, and upregulated the level of Tob2 in A549 cells. Conclusion: S115 exerts anticancer effects against a variety of cancer cells in vitro and in grafted cancer models by inducing apoptosis, downregulating ubiquitin and upregulating Tob2. PMID:25220642

Liu, Min-yu; Xiao, Lin; Dong, Yu-qiong; Liu, Ying; Cai, Li; Xiong, Wei-xia; Yao, Yu-long; Yin, Ming; Liu, Quan-hai

2014-01-01

126

Antiviral activity against the hepatitis C virus (HCV) of 1-indanone thiosemicarbazones and their inclusion complexes with hydroxypropyl-?-cyclodextrin.  

PubMed

The hepatitis C virus (HCV) is a major cause of acute and chronic hepatitis in humans. Approximately 5% of the infected people die from cirrhosis or hepatocellular carcinoma. The current standard therapy comprises a combination of pegylated-interferon alpha and ribavirin. Due to the relatively low effectiveness, the prohibitive costs and the extensive side effects of the treatment, an intense research for new direct-acting anti-HCV agents is taking place. Furthermore, NS3 protease inhibitors recently introduced into the market are not effective against all HCV subgenotypes. Thiosemicarbazones (TSCs) have shown antiviral activity against a wide range of DNA and RNA viruses. However, their extremely low aqueous solubility and high self-aggregation tendency often preclude their reliable biological evaluation in vitro. In this work, we investigated and compared for the first time the anti-HCV activity of two 1-indanone TSCs, namely 5,6-dimethoxy-1-indanone TSC and 5,6-dimethoxy-1-indanone N4-allyl TSC, and their inclusion complexes with hydroxypropyl-?-cyclodextrin (HP?-CD) in Huh-7.5 cells containing the full-length and the subgenomic subgenotype 1b HCV replicon system. Studies of physical stability in culture medium showed that free TSCs precipitated rapidly and formed submicron aggregates. Conversely, TSC complexation with HP?-CD led to more stable systems with minimal size growth and drug concentration loss. More importantly, both TSCs and their inclusion complexes displayed a potent suppression of the HCV replication in both cell lines with no cytotoxic effects. The mechanism likely involves the inhibition of non-structural proteins of the virus. In addition, findings suggested that the cyclodextrin released the drug to the culture medium over time. This platform could be exploited for the study of the drug toxicity and pharmacokinetics animal models. PMID:22885176

Glisoni, Romina J; Cuestas, María L; Mathet, Verónica L; Oubiña, José R; Moglioni, Albertina G; Sosnik, Alejandro

2012-10-01

127

Structural, spectral, electrochemistry, thermal properties and theoretical studies on 4-[N, N-di(4-tolyl)amino] benzaldehyde-2-chloro benzoylhydrazone  

NASA Astrophysics Data System (ADS)

The title compound 4-[N, N-di(4-tolyl)amino] benzaldehyde-2-chloro benzoylhydrazone (C28H24ClN3O, Mr = 453.96) was synthesized by the reaction of 4-[N, N-di(4-tolyl)amino] benzaldehyde with 2-chlorobenzohydrazide, and its structure was characterized by IR, 1H NMR, 13H NMR, high-resolution mass spectrometry and single-crystal X-ray diffraction. The crystal belongs to Monoclinic, space group P2(1)/n with a = 12.626(3), b = 12.609(3), c = 15.837(3) Å, ? = 90.00(3)°, Z = 5, V = 2512.5(9) Å3, Mr = 453.95, Dc = 1.280 g/cm3, ? = 0.183 mm-1, F(0 0 0) = 1024, R = 0.0432 and wR = 0.1087. X-ray analysis revealed that one of the benzene ring and acylhydrazone were essentially planar, the 2-chloro benzene ring and amide were non-planar, the torsion angles C(1)sbnd C(6)sbnd C(7)sbnd O(1) and C(5)sbnd C(6)sbnd C(7)sbnd O(1) are 61.4(5)° and -114.4(4)°. The thermal stability studies indicate that the title compound is stable up to 341.1 °C. The spectral, electrochemistry properties and theoretical studies show that the title compound is a good candidate for the charge-transporting materials.

Lizeng, Liu; Wei, Li; Xianfang, Meng; Dongzhi, Liu; Gongfeng, Xu; Zhengchen, Bai

2014-11-01

128

A computational study of the enantioselective addition of n-BuLi to benzaldehyde in the presence of a chiral lithium N,P amide.  

PubMed

In the presence of a chiral lithium N,P amide, alkylation of benzaldehyde results in an enantioselective formation of 1-phenyl-pentanol. This stereoselective addition reaction has herein been studied using dispersion-corrected density functional theory. For five different chiral ligands originating from amino acids the resulting enantioselectivity has been computationally determined and compared with experimentally available enantiomeric ratios (e.r.). In all cases the experimentally preferred enantiomer could be reproduced by the computational model. The selectivity trend among the ligands was found strongly sensitive to the amount of dispersion correction included. The origin of selectivity in the alkylation reaction is found to be composed of many combined interactions. For the most selective ligand 2A the most important factors found, which are favouring the (R)-TS, are a CH-? interaction between benzaldehyde-dimethyl ether (DME), stronger Li-solvation, and Li-? interactions with the phenyl ring in the backbone of the chiral lithium N,P amide. In addition, solvation by the bulk solvent and the size of the substituent on the nitrogen are also found important factors for the enantioselectivity. PMID:22378179

Rönnholm, Petra; Gräfenstein, Jürgen; Norrby, Per-Ola; Hilmersson, Göran; Lill, Sten O Nilsson

2012-04-14

129

Novel Thiosemicarbazones Regulate the Signal Transducer and Activator of Transcription 3 (STAT3) Pathway: Inhibition of Constitutive and Interleukin 6-Induced Activation by Iron Depletion.  

PubMed

Pharmacologic manipulation of metal pools in tumor cells is a promising strategy for cancer treatment. Here, we reveal how the iron-binding ligands desferrioxamine (DFO), di-2-pyridylketone-4,4-dimethyl-3-thiosemicarbazone (Dp44mT), and di-2-pyridylketone 4-cyclohexyl-4-methyl-3-thiosemicarbazone (DpC) inhibit constitutive and interleukin 6-induced activation of signal transducer and activator of transcription 3 (STAT3) signaling, which promotes proliferation, survival, and metastasis of cancer cells. We demonstrate that DFO, Dp44mT, and DpC significantly decrease constitutive phosphorylation of the STAT3 transcription factor at Tyr705 in the pancreatic cancer cell lines PANC-1 and MIAPaCa-2 as well as the prostate cancer cell line DU145. These compounds also significantly decrease the dimerized STAT3 levels, the binding of nuclear STAT3 to its target DNA, and the expression of downstream targets of STAT3, including cyclin D1, c-myc, and Bcl-2. Examination of upstream mediators of STAT3 in response to these ligands has revealed that Dp44mT and DpC could significantly decrease activation of the nonreceptor tyrosine kinase Src and activation of cAbl in DU145 and MIAPaCa-2 cells. In contrast to the effects of Dp44mT, DpC, or DFO on inhibiting STAT3 activation, the negative control compound di-2-pyridylketone 2-methyl-3-thiosemicarbazone, or the DFO:Fe complex, which cannot bind cellular iron, had no effect. This demonstrates the role of iron-binding in the activity observed. Immunohistochemical staining of PANC-1 tumor xenografts showed a marked decrease in STAT3 in the tumors of mice treated with Dp44mT or DpC compared with the vehicle. Collectively, these studies demonstrate suppression of STAT3 activity by iron depletion in vitro and in vivo, and reveal insights into regulation of the critical oncogenic STAT3 pathway. PMID:25561562

Lui, Goldie Y L; Kovacevic, Zaklina; V Menezes, Sharleen; Kalinowski, Danuta S; Merlot, Angelica M; Sahni, Sumit; Richardson, Des R

2015-03-01

130

Synthesis and biological activities of 2,6-diaryl-3-methyl-4-piperidone derivatives.  

PubMed

In the present study, a new series of 2,6-diaryl-3-methyl-4-piperidones was synthesized by Mannich reaction (condensation) of ethyl-methyl ketone, substituted aromatic aldehydes and ammonium acetate. Oximes and thiosemicarbazone derivatives of 2,6-diaryl-3-methyl-4-piperidones were synthesized by reaction with hydroxylamine hydrochloride and thiosemicarbazide respectively. The chemical structures were confirmed by means of IR, 1H-, 13C-NMR and mass spectral data. The compounds were screened for acute toxicity, analgesic, local anaesthetic and antifungal activity. 2-(4-Methylphenyl)-3-methyl-6-(4-chlorophenyl)-piperidin-4-one 2 exhibited the highest analgesic and local anaesthetic activity. The oximes and thiosemicarbazones were completely devoid of analgesic and local anaesthetic activity. 2-(4-Methylphenyl)-3-methyl-6-(4-hydroxyphenyl)-piperidin-4-oxime 21 and 2-(4-methoxyphenyl)-3-methyl-6-(4-chlorophenyl)-piperidin-4-oxime 17 exhibited potent antifungal activity against Aspergillus niger. Antifungal activity against Candida albicans was observed only with 2-(4-dimethylaminophenyl)-3-methyl-6-(4-chlorophenyl)-piperidin-4-oxime 20. 2,6-Diaryl-3-methyl-4-piperidones did not exhibit antifungal property. PMID:12576678

Rameshkumar, Natesh; Veena, Anantharaman; Ilavarasan, Raju; Adiraj, Mandaleeswaran; Shanmugapandiyan, Pitchaimuthu; Sridhar, Seshaiah Krishnan

2003-02-01

131

Active-Site Engineering of Benzaldehyde Lyase Shows That a Point Mutation Can Confer Both New Reactivity and Susceptibility to Mechanism-Based Inhibition  

SciTech Connect

Benzaldehyde lyase (BAL) from Pseudomonas putida is a thiamin diphosphate (ThDP)-dependent enzyme that catalyzes the breakdown of (R)-benzoin. Here we report that a point mutant, BAL A28S, not only catalyzes the decarboxylation of benzoylformate but, like benzoylformate decarboxylase (BFDC), is also inactivated by the benzoylformate analogues methyl benzoylphosphonate (MBP) and benzoylphosphonate (BP). The latter has no effect on wild-type BAL, and the inactivation of the A28S variant is shown to result from phosphorylation of the newly introduced serine residue. This lends support to the proposal that an appropriately placed nucleophile facilitates the expulsion of carbon dioxide from the active site in many ThDP-dependent decarboxylases.

Brandt, Gabriel S.; Kneen, Malea M.; Petsko, Gregory A.; Ringe, Dagmar; McLeish, Michael J. (Brandeis); (IUPUI)

2010-02-11

132

Synthesis, characterization, and anticancer activity of a series of ketone-N(4)-substituted thiosemicarbazones and their ruthenium(II) arene complexes.  

PubMed

A series of ketone-N(4)-substituted thiosemicarbazone (TSC) compounds (L1-L9) and their corresponding [(?(6)-p-cymene)Ru(II)(TSC)Cl](+/0) complexes (1-9) were synthesized and characterized by NMR, IR, elemental analysis, and HR-ESI-mass spectrometry. The molecular structures of L4, L9, 1-6, and 9 were determined by single-crystal X-ray diffraction analysis. The compounds were further evaluated for their in vitro antiproliferative activities against the SGC-7901 human gastric cancer, BEL-7404 human liver cancer, and HEK-293T noncancerous cell lines. Furthermore, the interactions of the compounds with DNA were followed by electrophoretic mobility spectrometry studies. PMID:24143913

Su, Wei; Qian, Quanquan; Li, Peiyuan; Lei, Xiaolin; Xiao, Qi; Huang, Shan; Huang, Chusheng; Cui, Jianguo

2013-11-01

133

High efficient photocatalytic selective oxidation of benzyl alcohol to benzaldehyde by solvothermal-synthesized ZnIn{sub 2}S{sub 4} microspheres under visible light irradiation  

SciTech Connect

Hexagonal ZnIn{sub 2}S{sub 4} samples have been synthesized by a solvothermal method. Their properties have been determined by X-ray diffraction, ultraviolet–visible-light diffuse reflectance spectra, field emission scanning electron microscopy, nitrogen adsorption–desorption and X-ray photoelectron spectra. These results demonstrate that ethanol solvent has significant influence on the morphology, optical and electronic nature for such marigold-like ZnIn{sub 2}S{sub 4} microspheres. The visible light photocatalytic activities of the ZnIn{sub 2}S{sub 4} have been evaluated by selective oxidation of benzyl alcohol to benzaldehyde using molecular oxygen as oxidant. The results show that 100% conversion along with >99% selectivity are reached over ZnIn{sub 2}S{sub 4} prepared in ethanol solvent under visible light irradiation (?>420 nm) of 2 h, but only 58% conversion and 57% yield are reached over ZnIn{sub 2}S{sub 4} prepared in aqueous solvent. A possible mechanism of the high photocatalytic activity for selective oxidation of benzyl alcohol over ZnIn{sub 2}S{sub 4} is proposed and discussed. - Graphical abstract: Marigold-like ZnIn{sub 2}S{sub 4} microspheres were synthesized by a solvothermal method. The high visible photocatalytic activities of ZnIn{sub 2}S{sub 4} were evaluated by selective oxidation of benzyl alcohol to benzaldehyde under mild conditions. Display Omitted - Highlights: • Marigold-like ZnIn{sub 2}S{sub 4} microspheres were synthesized by a solvothermal method. • The solvents have a remarkably influence on the morphology and properties of samples. • It is the first time to apply ZnIn{sub 2}S{sub 4} for selective oxidation of benzyl alcohol. • ZnIn{sub 2}S{sub 4} shows high photocatalytic activity for selective oxidation of benzyl alcohol.

Chen, Zhixin, E-mail: czx@fzu.edu.cn [State Key Laboratory Breeding Base of Photocatalysis, College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350002 (China); Instrumental Measurement and Analysis Center, Fuzhou University, Fuzhou 350002 (China); Xu, Jingjing; Ren, Zhuyun [State Key Laboratory Breeding Base of Photocatalysis, College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350002 (China); He, Yunhui; Xiao, Guangcan [State Key Laboratory Breeding Base of Photocatalysis, College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350002 (China); Instrumental Measurement and Analysis Center, Fuzhou University, Fuzhou 350002 (China)

2013-09-15

134

Enantioselective direct aldol reactions catalyzed by L-prolinamide derivatives.  

PubMed

l-Prolinamides 2, prepared from l-proline and simple aliphatic and aromatic amines, have been found to be active catalysts for the direct aldol reaction of 4-nitrobenzaldehyde with neat acetone at room temperature. They give moderate enantioselectivities of up to 46% enantiomeric excess (ee). The enantioselectivity increases as the amide N-H becomes a better hydrogen bond donor. l-Prolinamides 3, derived from the reaction of l-proline with alpha,beta-hydroxyamines such that there is a terminal hydroxyl group, show more efficient catalysis and higher enantioselectivities. In particular, catalyst 3h, prepared from l-proline and (1S,2S)-diphenyl-2-aminoethanol, exhibits high enantioselectivities of up to 93% ee for aromatic aldehydes and up to >99% ee for aliphatic aldehydes under -25 degrees C. Model reactions of benzaldehyde with three enamines derived from the condensation of prolinamides with acetone have been studied by quantum mechanics calculations. The calculations reveal that the amide N-H and the terminal hydroxyl groups form hydrogen bonds with the benzaldehyde substrate. These hydrogen bonds reduce the activation energy and cause high enantioselectivity. Our results suggest a new strategy in the design of new organic catalysts for direct asymmetric aldol reactions and related transformations. PMID:15079057

Tang, Zhuo; Jiang, Fan; Cui, Xin; Gong, Liu-Zhu; Mi, Ai-Qiao; Jiang, Yao-Zhong; Wu, Yun-Dong

2004-04-20

135

Synthesis, crystal structure, computational and photophysical studies of new hydrazono-thiazole derivatives decorated with N-methyl tetrahydrocarbazole pendant  

NASA Astrophysics Data System (ADS)

2,3-Dihydro-1H-carbazol-4(9H)-one, obtained from 2,3-Dichloro-5,6-Dicyanobenzoquinone (DDQ) oxidation of tetrahydrocarbazole, on methylation with N, N-dimethylformamide dimethyl acetal (DMF-DMA) furnish N-methyl derivative. The thiosemicarbazone of N-methyl derivative on reaction with 2-bromopropionic acid, ethyl bromopyruvate and dimethyl acetylenedicarboxylate (DMAD) afford hydrazono-thiazolidin-4-one derivatives with tetrahydrocarbazole pendant. X-ray diffraction and DFT studies of (Z)-5-methyl-2-((E)-(9-methyl-2,3-dihydro-1H-carbazol-4(9H)-ylidene)hydrazono)thiazolidin-4-one 5 have been reported. The reaction with dimethyl acetylenedicarboxylate (DMAD) and ethyl bromopyruvate take place without any catalyst and organic solvent. The photophysical properties of these compounds were studied by means of UV/visible absorption spectroscopy and fluorescence spectroscopy.

Gautam, Deepika; Chaudhary, R. P.

2015-01-01

136

Anti-plasmodial activity of aroylhydrazone and thiosemicarbazone iron chelators: effect on erythrocyte membrane integrity, parasite development and the intracellular labile iron pool.  

PubMed

Iron chelators inhibit the growth of the malaria parasite, Plasmodium falciparum, in culture and in animal and human studies. We previously reported the anti-plasmodial activity of the chelators, 2-hydroxy-1-naphthylaldehyde isonicotinoyl hydrazone (311), 2-hydroxy-1-naphthylaldehyde 4-methyl-3-thiosemicarbazone (N4mT), and 2-hydroxy-1-naphthylaldehyde 4-phenyl-3-thiosemicarbazone (N4pT). In fact, these ligands showed greater growth inhibition of chloroquine-sensitive (3D7) and chloroquine-resistant (7G8) strains of P. falciparum in culture compared to desferrioxamine (DFO). The present study examined the effects of 311, N4mT and N4pT on erythrocyte membrane integrity and asexual parasite development. While the characteristic biconcave disk shape of the erythrocytes was unaffected, the chelators caused very slight hemolysis at IC50 values that inhibited parasite growth. The chelators 311, N4mT and N4pT affected all stages of the intra-erythrocytic development cycle (IDC) of P. falciparum in culture. However, while these ligands primarily affected the ring-stage, DFO inhibited primarily trophozoite and schizont-stages. Ring, trophozoite and schizont-stages of the IDC were inhibited by significantly lower concentrations of 311, N4mT, and N4pT (IC50=4.45±1.70, 10.30±4.40, and 3.64±2.00?M, respectively) than DFO (IC50=23.43±3.40?M). Complexation of 311, N4mT and N4pT with iron reduced their anti-plasmodial activity. Estimation of the intracellular labile iron pool (LIP) in erythrocytes showed that the chelation efficacy of 311, N4mT and N4pT corresponded to their anti-plasmodial activities, suggesting that the LIP may be a potential source of non-heme iron for parasite metabolism within the erythrocyte. This study has implications for malaria chemotherapy that specifically disrupts parasite iron utilization. PMID:24028863

Walcourt, Asikiya; Kurantsin-Mills, Joseph; Kwagyan, John; Adenuga, Babafemi B; Kalinowski, Danuta S; Lovejoy, David B; Lane, Darius J R; Richardson, Des R

2013-12-01

137

Anti-Plasmodial Activity of Aroylhydrazone and Thiosemicarbazone Iron Chelators: Effect on Erythrocyte Membrane Integrity, Parasite Development and the Intracellular Labile Iron Pool  

PubMed Central

Iron chelators inhibit the growth of the malaria parasite, Plasmodium falciparum, in culture and in animal and human studies. We previously reported the anti-plasmodial activity of the chelators, 2-hydroxy-1-naphthylaldehyde isonicotinoyl hydrazone (311), 2-hydroxy-1-naphthylaldehyde 4-methyl-3-thiosemicarbazone (N4mT), and 2-hydroxy-1-naphthylaldehyde 4-phenyl-3-thiosemicarbazone (N4pT). In fact, these ligands showed greater growth inhibition of chloroquine-sensitive (3D7) and chloroquine-resistant (7G8) strains of P. falciparum in culture compared to desferrioxamine (DFO). The present study examined the effects of 311, N4mT and N4pT on erythrocyte membrane integrity and asexual parasite development. While the characteristic biconcave disk shape of the erythrocytes was unaffected, the chelators caused very slight hemolysis at IC50 values that inhibited parasite growth. The chelators 311, N4mT and N4pT affected all stages of the intra-erythrocytic development cycle (IDC) of P. falciparum in culture. However, while these ligands primarily affected the ring-stage, DFO inhibited primarily trophozoite and schizont-stages. Ring, trophozoite and schizont-stages of the IDC were inhibited by significantly lower concentrations of 311, N4mT, and N4pT (IC50 = 4.45 ± 1.70, 10.30 ± 4.40, and 3.64 ± 2.00 ?M, respectively) than DFO (IC50 = 23.43 ± 3.40 ?M). Complexation of 311, N4mT and N4pT with iron reduced their anti-plasmodial activity. Estimation of the intracellular labile iron pool (LIP) in erythrocytes showed that the chelation efficacy of 311, N4mT and N4pT corresponded to their anti-plasmodial activity, suggesting that the LIP may be a potential source of non-heme iron for parasite metabolism within the erythrocyte. This study has implications for malaria chemotherapy that specifically disrupts parasite iron utilization. PMID:24028863

Walcourt, Asikiya; Kurantsin-Mills, Joseph; Kwagyan, John; Adenuga, Babafemi B.; Kalinowski, Danuta S.; Lovejoy, David B.; Lane, Darius J. R.; Richardson, Des R.

2013-01-01

138

Solvent-dependent mixed complex formation-NMR studies and asymmetric addition reactions of lithioacetonitrile to benzaldehyde mediated by chiral lithium amides.  

PubMed

Lithioacetonitrile and a chiral lithium amide with an internally coordinating methoxy group form mixed dimers in diethyl ether (DEE) and in tetrahydrofuran (THF) according to NMR studies. Based on the observed (6)Li,(1)H heteronuclear Overhauser effects, in THF lithioacetonitrile is present in a mixed complex with the chiral lithium amide, and this complex has a central N-Li-N-Li core. In DEE, on the other hand, the acetonitrile anion bridges two lithiums of the dimer to form a central six-membered Li-N-C-C-Li-N ring. Gauge individual atomic orbital DFT calculations of the (13)C NMR chemical shifts of the DEE- and THF-solvated mixed dimers show good agreement with those obtained experimentally. Lithioacetonitrile complexed to the chiral lithium amide has been employed in asymmetric addition to benzaldehyde in both DEE and THF. In THF the product, (S)-3-phenyl-3-hydroxy propionitrile, is formed in 55 % ee and in DEE the R enantiomer is formed in 45 % ee. This change in stereoselectivity between solutions in DEE and THF was found to be general among a number of different chiral lithium amides, all with an internal chelating methoxy group. PMID:11981893

Sott, Richard; Granander, Johan; Hilmersson, Göran

2002-05-01

139

Ab-initio and DFT calculations on molecular structure, NBO, HOMO-LUMO study and a new vibrational analysis of 4-(Dimethylamino) Benzaldehyde.  

PubMed

The experimental and theoretical study on the molecular structure and a new vibrational analysis of 4-(Dimethylamino) Benzaldehyde (DMABA) is presented. The IR and Raman spectra were recorded in solid state. Optimized geometry, vibrational frequencies and various thermodynamic parameters of the title compound were calculated using DFT methods and are in agreement with the experimental values. A detailed interpretation of the IR and Raman spectra of the title compound were reported. The stability of the molecule arising from hyper-conjugative interactions and charge delocalization has been analyzed using NBO analysis and AIM approach. The HOMO and LUMO analysis were used to determine the charge transfer within the molecule and some molecular properties such as ionization potential, electron affinity, electronegativity, chemical potential, hardness, softness and global electrophilicity index. The TD-DFT approach was applied to assign the electronic transitions observed in the UV-visible spectrum measured experimentally. Molecular electrostatic potential map was performed by the DFT method. According to DSC measurements, the substance presents a melting point of 72.34°C and decomposes at temperatures higher than 193°C. PMID:25448963

Rocha, Mariana; Di Santo, Alejandro; Arias, Juan Marcelo; Gil, Diego M; Ben Altabef, Aída

2015-02-01

140

Spectroscopic (FT-IR, FT-Raman) and quantum mechanical studies of 3t-pentyl-2r,6c-diphenylpiperidin-4-one thiosemicarbazone  

NASA Astrophysics Data System (ADS)

In this study, the molecular structure and vibrational spectra of 3t-pentyl2r,6c-diphenylpiperidin-4-one thiosemicarbazone (PDPOTSC) were studied. The ground-state molecular geometry was ascertained by using the density functional theory (DFT)/B3LYP method using 6-31++G(d,p) as a basis set. The vibrational (FT-IR and FT-Raman) spectra of PDPOTSC were computed using DFT/B3LYP and HF methods with 6-31++G(d,p) basis set. The fundamental vibrations were assigned on the basis of the total energy distribution (TED ? 10%) of the vibrational modes, calculated with scaled quantum mechanics (SQM) methods PQS program. The electrical dipole moment (?) and first hyperpolarizability (?o) values have been computed using DFT/B3LYP and HF methods. The calculated result (?o) shows that the title molecule might have nonlinear optical (NLO) behavior. Atomic charges of C, N, S and molecular electrostatic potential (MEP) were calculated using B3LYP/6-31G++(d,p). The HOMO-LUMO energies were calculated and natural bonding orbital (NBO) analysis has also been carried out.

Savithiri, S.; Arockia doss, M.; Rajarajan, G.; Thanikachalam, V.; Bharanidharan, S.; Saleem, H.

2015-02-01

141

Spectroscopic characterization, antioxidant and antitumour studies of novel bromo substituted thiosemicarbazone and its copper(II), nickel(II) and palladium(II) complexes.  

PubMed

A new, slightly distorted octahedral complex of copper(II), square planar complexes of nickel(II) and palladium(II) with 2,4'-dibromoacetophenone thiosemicarbazone (DBAPTSC) are synthesized. The ligand and the complexes are characterized by FT-IR, FT-Raman, powder X-ray diffraction studies. The IR and Raman data are correlated for the presence of the functional groups which specifically helped in the confirmation of the compounds. In addition, the free ligand is unambiguously characterized by (1)H and (13)C NMR spectroscopy while the copper(II) complex is characterized by electron paramagnetic resonance spectroscopy (EPR). The g values for the same are found to be 2.246 (g1), 2.012 (g2) and 2.005 (g3) which suggested rhombic distortions. The HOMO-LUMO band gap calculations for these compounds are found to be in between 0.5 and 4.0 eV and these compounds are identified as semiconducting materials. The synthesized ligand and its copper(II), nickel(II) and palladium(II) complexes are subjected to antitumour activity against the HepG2 human hepatoblastoma cell lines. Among all the compounds, nickel(II) complex is found to exert better antitumour activity with 57.6% of cytotoxicity. PMID:25064500

Jagadeesh, M; Lavanya, M; Kalangi, Suresh K; Sarala, Y; Ramachandraiah, C; Varada Reddy, A

2015-01-25

142

Spectroscopic characterization, antioxidant and antitumour studies of novel bromo substituted thiosemicarbazone and its copper(II), nickel(II) and palladium(II) complexes  

NASA Astrophysics Data System (ADS)

A new, slightly distorted octahedral complex of copper(II), square planar complexes of nickel(II) and palladium(II) with 2,4?-dibromoacetophenone thiosemicarbazone (DBAPTSC) are synthesized. The ligand and the complexes are characterized by FT-IR, FT-Raman, powder X-ray diffraction studies. The IR and Raman data are correlated for the presence of the functional groups which specifically helped in the confirmation of the compounds. In addition, the free ligand is unambiguously characterized by 1H and 13C NMR spectroscopy while the copper(II) complex is characterized by electron paramagnetic resonance spectroscopy (EPR). The g values for the same are found to be 2.246 (g1), 2.012 (g2) and 2.005 (g3) which suggested rhombic distortions. The HOMO-LUMO band gap calculations for these compounds are found to be in between 0.5 and 4.0 eV and these compounds are identified as semiconducting materials. The synthesized ligand and its copper(II), nickel(II) and palladium(II) complexes are subjected to antitumour activity against the HepG2 human hepatoblastoma cell lines. Among all the compounds, nickel(II) complex is found to exert better antitumour activity with 57.6% of cytotoxicity.

Jagadeesh, M.; Lavanya, M.; Kalangi, Suresh K.; Sarala, Y.; Ramachandraiah, C.; Varada Reddy, A.

2015-01-01

143

Identification of in vitro metabolites of the novel anti-tumor thiosemicarbazone, DpC, using ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry.  

PubMed

Di-2-pyridylketone-4-cyclohexyl-4-methyl-3-thiosemicarbazone (DpC) is a promising analogue of the dipyridyl thiosemicarbazone class currently under development as a potential anti-cancer drug. In fact, this class of agents shows markedly greater anti-tumor activity and selectivity than the clinically investigated thiosemicarbazone, Triapine®. However, further development of DpC requires detailed data concerning its metabolism. Therefore, we focused on the identification of principal phase I and II metabolites of DpC in vitro. DpC was incubated with human liver microsomes/S9 fractions and the samples were analyzed using ultra-performance liquid chromatography (UPLC(TM)) with electrospray ionization quadrupole-time-of-flight (Q-TOF) mass spectrometry. An Acquity UPLC BEH C(18) column was implemented with 2 mM ammonium acetate and acetonitrile in gradient mode as the mobile phase. The chemical structures of metabolites were proposed based on the accurate mass measurement of the protonated molecules as well as their main product ions. Ten phase I and two phase II metabolites were detected and structurally described. The metabolism of DpC occurred via oxidation of the thiocarbonyl group, hydroxylation and N-demethylation, as well as the combination of these reactions. Conjugates of DpC and the metabolite, M10, with glucuronic acid were also observed as phase II metabolites. Neither sulfate nor glutathione conjugates were detected. This study provides the first information about the chemical structure of the principal metabolites of DpC, which supports the development of this promising anti-cancer drug and provides vital data for further pharmacokinetic and in vivo metabolism studies. PMID:23180090

Stariat, Ján; Kova?íková, Petra; Ku?era, Radim; Klimeš, Ji?í; Kalinowski, Danuta S; Richardson, Des R; Ketola, Raimo A

2013-02-01

144

Selective separation of palladium (II) from precious metal ions using thiosemicarbazone derivatives from acidic media by solid phase and solvent extractions  

Microsoft Academic Search

A newly reported chelating ligand, 9,10-phenanthraquinone ethylthiosemicarbazone (PET), has been used for selective separation of Pd(II) by solid phase extraction (SPE) and solvent extraction (SE) in highly acidic media. PET was chemically immobilized on aminopropylsilica gel, yielding PET-SG, and complexes of PET and PET-SG with Pd(II) were synthesized and confirmed by IR, UV, thermal and elemental analyses. Free PET forms

Mohamed M. Hassanien; Khaled S. Abou-El-Sherbini

2010-01-01

145

A multicenter phase II trial of 3-aminopyridine-2-carboxaldehyde thiosemicarbazone (3AP, Triapine ® ) and gemcitabine in advanced non-small-cell lung cancer with pharmacokinetic evaluation using peripheral blood mononuclear cells  

Microsoft Academic Search

Summary  \\u000a Background: We tested the hypothesis that 3-aminopyridine-2-carboxaldehyde thiosemicarbazone (3-AP, Triapine®) may enhance response to\\u000a re-treatment with gemcitabine by enhancing intracellular uptake of gemcitabine in a phase II study. Method: Patients who had prior exposure to gemcitabine as a first-line treatment of advanced non-small-cell lung cancer (NSCLC) were\\u000a given weekly infusions of 3-AP and gemcitabine for 3 weeks followed by 1 week

Brigette Ma; Boon Cher Goh; Eng Huat Tan; Kwok Chi Lam; Ross Soo; Swan Swan Leong; Ling Zhi Wang; Frankie Mo; Anthony T. C. Chan; Benny Zee; Tony Mok

2008-01-01

146

Vibrational spectroscopy (FT-IR and Laser-Raman) investigation, and computational (M06-2X and B3LYP) analysis on the structure of 4-(3-fluorophenyl)-1-(propan-2-ylidene)-thiosemicarbazone.  

PubMed

In this study, the experimental and theoretical vibrational spectral analysis of 4-(3-fluorophenyl)-1-(propan-2-ylidene)-thiosemicarbazone have been carried out. The experimental FT-IR (4000-400 cm(-1)) and Laser-Raman spectra (4000-100 cm(-1)) have been recorded for the solid state samples. The theoretical vibrational frequencies and the optimized geometric parameters (bond lengths and angles) have been calculated for gas phase using density functional theory (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr) and M06-2X (the highly parametrized, empirical exchange correlation function) quantum chemical methods with 6-311++G(d,p) basis set. The diversity in molecular geometry of fluorophenyl substituted thiosemicarbazones has been discussed based on the X-ray crystal structure reports and theoretical calculation results from the literature. The assignments of the vibrational frequencies have been done on the basis of potential energy distribution (PED) analysis by using VEDA4 software. A good correlation was found between the computed and experimental geometric and vibrational data. In addition, the highest occupied (HOMO) and lowest unoccupied (LUMO) molecular orbital energy levels and other related molecular energy values of the compound have been determined using the same level of theoretical calculations. PMID:24662757

Sert, Yusuf; Miroslaw, Barbara; Ç?rak, Ça?r?; Do?an, Hatice; Szulczyk, Daniel; Struga, Marta

2014-07-15

147

Phase I study of the ribonucleotide reductase inhibitor 3-aminopyridine-2-carboxaldehyde-thiosemicarbazone (3-AP) in combination with high dose cytarabine in patients with advanced myeloid leukemia  

PubMed Central

Summary Purpose This Phase I dose escalation study was based on the hypothesis that the addition of 3-aminopyridine-2-carboxaldehyde-thiosemicarbazone (3-AP) to cytarabine would enhance cytarabine cytotoxicity. The primary objective of the study was to establish the maximum tolerated dose of 3-AP when given in combination with a fixed dose of cytarabine. Experimental design Twenty-five patients with relapsed or refractory myeloid leukemia were enrolled to three dose levels of 3-AP. Cytarabine was administered as a 2 h infusion at a fixed dose of 1,000 mg/m2/day for 5 consecutive days. Escalating doses of 3-AP as a 2 h infusion were administered on days 2 through 5. The 3-AP infusion preceded the start of the cytarabine infusion by 4 h. Results In general, the toxicities observed with the combination were similar to the expected toxicity profile for cytarabine when utilized as a single agent at this dose and schedule. However, two of three patients developed dose-limiting methemoglobinemia at the highest 3-AP dose studied (100 mg/m2). Transient reversible methemoglobinemia was documented in 11 of 15 patients enrolled at the 75 mg/m2 dose level. Objective evidence of clinical activity was observed in four patients. Conclusions The combination of 3-AP and cytarabine given on this schedule is feasible in advanced myeloid leukemia. The recommended Phase II dose is 75 mg/m2/day of 3-AP on days 2–5 given prior to cytarabine administered at a dose of 1,000 mg/m2/day over 5 consecutive days. Methemoglobinemia is a common toxicity of this combination and requires close monitoring. PMID:18217206

Larson, Richard A.; Gajria, Devika; Dolan, M. Eileen; Delaney, Shannon M.; Karrison, Theodore G.; Ratain, Mark J.; Stock, Wendy

2014-01-01

148

Exploring the Anti-Cancer Activity of Novel Thiosemicarbazones Generated through the Combination of Retro-Fragments: Dissection of Critical Structure-Activity Relationships  

PubMed Central

Thiosemicarbazones (TSCs) are an interesting class of ligands that show a diverse range of biological activity, including anti-fungal, anti-viral and anti-cancer effects. Our previous studies have demonstrated the potent in vivo anti-tumor activity of novel TSCs and their ability to overcome resistance to clinically used chemotherapeutics. In the current study, 35 novel TSCs of 6 different classes were designed using a combination of retro-fragments that appear in other TSCs. Additionally, di-substitution at the terminal N4 atom, which was previously identified to be critical for potent anti-cancer activity, was preserved through the incorporation of an N4-based piperazine or morpholine ring. The anti-proliferative activity of the novel TSCs were examined in a variety of cancer and normal cell-types. In particular, compounds 1d and 3c demonstrated the greatest promise as anti-cancer agents with potent and selective anti-proliferative activity. Structure-activity relationship studies revealed that the chelators that utilized “soft” donor atoms, such as nitrogen and sulfur, resulted in potent anti-cancer activity. Indeed, the N,N,S donor atom set was crucial for the formation of redox active iron complexes that were able to mediate the oxidation of ascorbate. This further highlights the important role of reactive oxygen species generation in mediating potent anti-cancer activity. Significantly, this study identified the potent and selective anti-cancer activity of 1d and 3c that warrants further examination. PMID:25329549

Rasko, Nathalie; Pot??ková, Eliška; Mrozek-Wilczkiewicz, Anna; Musiol, Robert; Ma?ecki, Jan G.; Sajewicz, Mieczys?aw; Ratuszna, Alicja; Muchowicz, Angelika; Go??b, Jakub; Šim?nek, Tomáš; Richardson, Des R.; Polanski, Jaroslaw

2014-01-01

149

Crystal structure of 3-[({2-[bis­(2-hy­droxy­benz­yl)amino]­eth­yl}(2-hy­droxy­benz­yl)amino)­meth­yl]-2-hydroxy-5-methyl­benzaldehyde  

PubMed Central

The non-symmetric title mol­ecule, C32H34N2O5, is based on a tetra­substituted ethyl­enedi­amine backbone. The mol­ecular structure consists of three hy­droxy­benzyl groups and one 2-hy­droxy-5-methyl­benzaldehyde group bonded to the N atoms of the di­amine unit. The ethyl­enedi­amine skeleton shows a regular extended conformation, while the spatial orientation of the phenol arms is governed by hydrogen bonds. In the 2-hy­droxy-5-methyl­benzaldehyde group, an intra­molecular S(6) O—H?O hydrogen bond is observed between the alcohol and aldehyde functions, and the neighbouring phenol arm participates in an intra­molecular S(6) O—H?N hydrogen bond. The third phenol group is involved in a bifurcated intra­molecular hydrogen bond with graph-set notation S(6) for O—H?N and O—H?O intra­molecular hydrogen bonds between neighbouring amine and phenol arms, respectively. Finally, the fourth phenol group acts as an acceptor in a bifurcated intra­molecular hydrogen bond and also acts as donor in an inter­molecular hydrogen bond, which connects inversion-related mol­ecules into dimers with R 4 4(8) ring motifs. PMID:25552993

Fonseca, Alexandra S.; Bortoluzzi, Adailton J.

2014-01-01

150

Crystal structure of 3-[({2-[bis-(2-hy-droxy-benz-yl)amino]-eth-yl}(2-hy-droxy-benz-yl)amino)-meth-yl]-2-hydroxy-5-methyl-benzaldehyde.  

PubMed

The non-symmetric title mol-ecule, C32H34N2O5, is based on a tetra-substituted ethyl-enedi-amine backbone. The mol-ecular structure consists of three hy-droxy-benzyl groups and one 2-hy-droxy-5-methyl-benzaldehyde group bonded to the N atoms of the di-amine unit. The ethyl-enedi-amine skeleton shows a regular extended conformation, while the spatial orientation of the phenol arms is governed by hydrogen bonds. In the 2-hy-droxy-5-methyl-benzaldehyde group, an intra-molecular S(6) O-H?O hydrogen bond is observed between the alcohol and aldehyde functions, and the neighbouring phenol arm participates in an intra-molecular S(6) O-H?N hydrogen bond. The third phenol group is involved in a bifurcated intra-molecular hydrogen bond with graph-set notation S(6) for O-H?N and O-H?O intra-molecular hydrogen bonds between neighbouring amine and phenol arms, respectively. Finally, the fourth phenol group acts as an acceptor in a bifurcated intra-molecular hydrogen bond and also acts as donor in an inter-molecular hydrogen bond, which connects inversion-related mol-ecules into dimers with R 4 (4)(8) ring motifs. PMID:25552993

Fonseca, Alexandra S; Bortoluzzi, Adailton J

2014-12-01

151

Derivatives Page  

NSDL National Science Digital Library

Derivatives are financial securities whose value is derived from another "underlying" financial security. Options, futures, swaps, swaptions, and structured notes are all examples of derivative securities. Derivatives can be used in hedging, protecting against financial risk, or can be used to speculate on the movement of commodity or security prices, interest rates, or the levels of financial indices. The valuation of derivatives makes use of the statistical mathematics of uncertainty. With links to related articles. See also Derivatives Concepts A-Z, glossary of derivatives-related terminology designed to make the other articles in the Financial Pipeline's Derivatives section easier to understand.

152

Efficient and versatile catalysis of N-alkylation of heterocyclic amines with alcohols and one-pot synthesis of 2-aryl substituted benzazoles with newly designed ruthenium(II) complexes of PNS thiosemicarbazones.  

PubMed

Ruthenium(II) carbonyl complexes with phosphine-functionalized PNS type thiosemicarbazone ligands [RuCl(CO)(EPh3)(L)] (1-6) (E = P or As, L = 2-(2-(diphenylphosphino)benzylidene) thiosemicarbazone (PNS-H), 2-(2-(diphenylphosphino)benzylidene)-N-methylthiosemicarbazone (PNS-Me), 2-(2-(diphenylphosphino)benzylidene)-N-phenylthiosemicarbazone (PNS-Ph)) have been synthesized and characterized by elemental analysis and spectroscopy (IR, UV-Vis, (1)H, (13)C, (31)P-NMR) as well as ESI mass spectrometry. The molecular structures of complexes 1, 2 and 6 were identified by means of single-crystal X-ray diffraction analysis. The analysis revealed that all the complexes possess a distorted octahedral geometry with the ligand coordinating in a uni-negative tridentate PNS fashion. All the ruthenium complexes (1-6) were tested as catalyst for N-alkylation of heteroaromatic amines with alcohols. Notably, complex 2 was found to be a very efficient and versatile catalyst towards N-alkylation of a wide range of heterocyclic amines with alcohols. Complex 2 can also catalyze the direct amination of 2-nitropyridine with benzyl alcohol to the corresponding secondary amine. Furthermore, a preliminary examination of performance for N,N-dialkylation of diamine showed promising results, giving good conversion and high selectivity. In addition, N-alkylation of ortho-substituted anilines (-NH2, -OH and -SH) led to the one-pot synthesis of 2-aryl substituted benzimidazoles, benzoxazoles and benzothiazoles, also revealing the catalytic activity of complex 2. PMID:24705796

Ramachandran, Rangasamy; Prakash, Govindan; Selvamurugan, Sellappan; Viswanathamurthi, Periasamy; Malecki, Jan Grzegorz; Ramkumar, Venkatachalam

2014-06-01

153

Synthesis of two new tripodal ligands and their cyclocondensation with 2-[2-(2-formylphenoxy)ethoxy]benzaldehyde in the presence of manganese(II) and cadmium(II) metal ions  

Microsoft Academic Search

Two new asymmetric tripodal tetraamine ligands, 2-((bis(2-aminoethyl)amino)methyl)benzenamine (L2) and 2-(((2-aminoethyl)(3-aminopropyl)amino)methyl)benzenamine (L3) were synthesized and characterized. [1+1] Macrocyclic Schiff-base complexes containing 1,2-diphenoxyethane head units and a 2-aminobenzyl pendant arm, were synthesized as [MnL4(MeOH)](ClO4)2 (1), [MnL5(MeOH)](ClO4)2 (2), [CdL4(H2O)](NO3)2 (3) and [CdL5(H2O)](NO3)2 (4) from the metal ion templated cyclocondensation reactions of 2-[2-(2-formylphenoxy)ethoxy]benzaldehyde with the (L2) or (L3) tripodal tetraamine ligands. The crystal structure

Hassan Keypour; Reza Azadbakht; Sadegh Salehzadeh; Hamid Khanmohammadi; Hamidreza Khavasi; Harry Adams

2008-01-01

154

Thermophysical and thermoacoustical properties of benzaldehyde mixtures with ethylbenzene at 303.15, 308.15, and 313.15 K and a pressure of 0.1 MPa  

NASA Astrophysics Data System (ADS)

Ultrasound velocity ( u), density (?) and viscosity (?) measurements of benzaldehyde + ethylbenzene mixtures have been carried out at 303.15, 308.15, and 313.15 K. These values have been used to calculate the excess molar volume ( V E), deviation in viscosity (??), and deviation in isentropic compressibility (??s), deviations in ultrasound velocity (? u), excess free volume (? V f), excess intermolecular free length (? L f) and excess Gibbs free energy of activation of viscous flow (? G E). McAllister's three body interaction model is used for correlating kinematic viscosity of binary mixtures. The excess values were correlated using the Redlich-Kister polynomial equation to obtain their coefficients and standard deviations. The thermophysical properties under the study were fit to the Jouyban-Acree model. The observed variation of these parameters helps in understanding the nature of interactions in these mixtures. Further, theoretical values of the ultrasound speed were evaluated using theories and empirical relations.

Saravanakumar, K.; Lavanya, T. G.; Baskaran, R.; Kubendran, T. R.

2012-04-01

155

Synthesis, characterization, optical band gap, in vitro antimicrobial activity and DNA cleavage studies of some metal complexes of pyridyl thiosemicarbazone  

NASA Astrophysics Data System (ADS)

A new series of Cr(III), Mn(II), Ni(II), Zn(II) and Hg(II) complexes of Schiff-bases derived from the condensation of 4-(2-pyridyl)-3-thiosemicarbazide and pyruvic acid (H2PTP) have been synthesized and characterized by spectroscopic studies. Schiff-base exhibit thiol-thione tautomerism wherein sulfur plays an important role in the coordination. The coordination possibility of the Schiff-bases towards metal ions have been proposed in the light of elemental analysis, spectral (IR, UV-vis, 1H NMR and 13C NMR), magnetic and thermal studies. IR spectra show that H2PTP is coordinated to the metal ions in a mononegative tridentate manner except in Cr(III) complex in which the ligand exhibits mononegative bidentate manner. The parameters total energy, binding energy, isolated atomic energy, electronic energy, heat of formation, dipole moment, HOMO and LUMO were calculated for the ligand and its complexes. Furthermore, the kinetic and thermodynamic parameters for the different decomposition steps were calculated using the Coats-Redfern and Horowitz-Metzger methods. Also, the optical band gap (Eg) of the metal complexes has been calculated. The optical transition energy (Eg) is direct and equals 3.20, 3.27 and 3.26 eV for Cr, Mn and Ni complexes, respectively. The synthesized ligand, in comparison to its metal complexes is screened for its antibacterial activity against the bacterial species, Bacillus thuringiensis, Staphylococcus aureus, Pseudomonas aeuroginosa and Escherichia coli. The results show that the metal complexes be more potent in activity antibacterial than the parent Shciff base ligand towards one or more bacterial species. Finally, the biochemical studies showed that, Mn complex have powerful and complete degradation effect on DNA.

Yousef, T. A.; Abu El-Reash, G. M.; El-Gammal, O. A.; Bedier, R. A.

2013-03-01

156

Antimycobacterial evaluation of novel [4,5-dihydro-1H-pyrazole-1-carbonyl]pyridine derivatives synthesized by microwave-mediated Michael addition.  

PubMed

The focus of this study is the synthesis and biological activity evaluation of a series of dibenzalaceton derivatives (3a-3n) and novel [4,5-dihydro-1H-pyrazole-1-carbonyl]pyridine derivatives (5a-5g) against Mycobacterium bovis, Bacillus Calmette-Guerin (BCG). Dibenzalacetone derivatives were synthesized by benzaldehyde derivatives. The [4,5-dihydro-1H-pyrazole-1-carbonyl]pyridine derivatives were synthesized by Michael addition reaction and using green chemistry microwave-mediated method. All compounds were evaluated against BCG and the activity expressed as minimum inhibitory concentration (MIC) in ?M. The result showed good activity for all the compounds especially compounds (3a), (3n), and (5a) illustrated high activity (7.03, 8.10 and 5.37??M, respectively). Copyright © 2014 John Wiley & Sons, Ltd. PMID:25219796

Sedighi, Vida; Azerang, Parisa; Sardari, Soroush

2014-09-14

157

Synthesis, spectral and antimicrobial studies of bis(cyclopentadienyl)titanium(IV) derivatives with Schiff bases derived from 2-amino-5-phenyl-1,3,4-thiadiazole.  

PubMed

The reactions of bis(cyclopentadienyl)titanium(IV) dichloride with Schiff bases derived by condensing 2- amino-5-phenyl-1,3,4-thiadiazole with benzaldehyde (SPT), 4-nitrobenzaldehyde (SNT), 4-methoxybenzaldehyde (SMT), 2-hydroxybenzaldehyde (SSTH) or 2-hydroxyacetophenone (SATH) have been studied in refluxing tetrahydrofuran and complexes of types [Cp(2)TiCl(SB)]Cl (SB= SPT, SNT or SMT) and [Cp(2)Ti(SB')]Cl (SB'H= SSTH or SATH) have been isolated. Tentative structural conclusions are drawn for these reaction products based upon elemental analyses, electrical conductance, magnetic moment and spectral (UV-vis, IR and (1)H NMR) data. Studies were conducted to assess the growth-inhibiting potential of the complexes synthesized, and the ligands, against various fungal and bacterial strains. PMID:18365105

Srivastava, A K; Pandey, O P; Sengupta, S K

2005-01-01

158

Electronic and vibrational spectra of protonated benzaldehyde-water clusters, [BZ-(H{sub 2}O){sub n?5}]H{sup +}: Evidence for ground-state proton transfer to solvent for n ? 3  

SciTech Connect

Vibrational and electronic photodissociation spectra of mass-selected protonated benzaldehyde-(water){sub n} clusters, [BZ-(H{sub 2}O){sub n}]H{sup +} with n ? 5, are analyzed by quantum chemical calculations to determine the protonation site in the ground electronic state (S{sub 0}) and ??{sup *} excited state (S{sub 1}) as a function of microhydration. IR spectra of [BZ-(H{sub 2}O){sub n}]H{sup +} with n ? 2 are consistent with BZH{sup +}-(H{sub 2}O){sub n} type structures, in which the excess proton is localized on benzaldehyde. IR spectra of clusters with n ? 3 are assigned to structures, in which the excess proton is located on the (H{sub 2}O){sub n} solvent moiety, BZ-(H{sub 2}O){sub n}H{sup +}. Quantum chemical calculations at the B3LYP, MP2, and ri-CC2 levels support the conclusion of proton transfer from BZH{sup +} to the solvent moiety in the S{sub 0} state for hydration sizes larger than the critical value n{sub c} = 3. The vibronic spectrum of the S{sub 1} ? S{sub 0} transition (??{sup *}) of the n = 1 cluster is consistent with a cis-BZH{sup +}-H{sub 2}O structure in both electronic states. The large blueshift of the S{sub 1} origin by 2106 cm{sup ?1} upon hydration with a single H{sub 2}O ligand indicates that the proton affinity of BZ is substantially increased upon S{sub 1} excitation, thus strongly destabilizing the hydrogen bond to the solvent. The adiabatic S{sub 1} excitation energy and vibronic structure calculated at the ri-CC2/aug-cc-pVDZ level agrees well with the measured spectrum, supporting the notion of a cis-BZH{sup +}-H{sub 2}O geometry. The doubly hydrated species, cis-BZH{sup +}-(H{sub 2}O){sub 2}, does not absorb in the spectral range of 23?000–27?400 cm{sup ?1}, because of the additional large blueshift of the ??{sup *} transition upon attachment of the second H{sub 2}O molecule. Calculations predict roughly linear and large incremental blueshifts for the ??{sup *} transition in [BZ-(H{sub 2}O){sub n}]H{sup +} as a function of n. In the size range n ? 3, the calculations predict a proton transfer from the (H{sub 2}O){sub n}H{sup +} solvent back to the BZ solute upon electronic ??{sup *} excitation.

Dopfer, Otto, E-mail: dopfer@physik.tu-berlin.de; Patzer, Alexander; Chakraborty, Shamik [Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstrasse 36, 10623 Berlin (Germany)] [Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstrasse 36, 10623 Berlin (Germany); Alata, Ivan; Omidyan, Reza; Broquier, Michel [Institut des Sciences Moleculaires d’Orsay, UMR-CNRS 8214, and Centre Laser de l’Université Paris Sud/LUMAT FR 2764, Batiment 106, l’Université Paris Sud 11, 91405 Orsay Cedex (France)] [Institut des Sciences Moleculaires d’Orsay, UMR-CNRS 8214, and Centre Laser de l’Université Paris Sud/LUMAT FR 2764, Batiment 106, l’Université Paris Sud 11, 91405 Orsay Cedex (France); Dedonder, Claude; Jouvet, Christophe [Physique des Interactions Ioniques et Moléculaires, UMR-CNRS 7345 Aix Marseille Université, Avenue Escadrille Normandie-Niémen, 13397 Marseille Cedex 20 (France)] [Physique des Interactions Ioniques et Moléculaires, UMR-CNRS 7345 Aix Marseille Université, Avenue Escadrille Normandie-Niémen, 13397 Marseille Cedex 20 (France)

2014-03-28

159

Benzyl derivatives with in vitro binding affinity for human opioid and cannabinoid receptors from the fungus Eurotium repens.  

PubMed

Bioassay-guided fractionation of the fungus Eurotium repens resulted in the isolation of two new benzyl derivatives, (E)-2-(hept-1-enyl)-3-(hydroxymethyl)-5-(3-methylbut-2-enyl)benzene-1,4-diol (1) and (E)-4-(hept-1-enyl)-7-(3-methylbut-2-enyl)-2,3-dihydrobenzofuran-2,5-diol (2), along with seven known compounds (3-9) including five benzaldehyde compounds, flavoglaucin (3), tetrahydroauroglaucin (4), dihydroauroglaucin (5), auroglaucin (6), and 2-(2',3-epoxy-1',3'- heptadienyl)-6-hydroxy-5-(3-methyl-2-butenyl)benzaldehyde (7), one diketopiperazine alkaloid, echinulin (8), and 5,7-dihydroxy-4-methylphthalide (9). The chemical structures of these compounds were established on the basis of extensive 1D and 2D NMR and HRMS data. Compounds 1-4 and 6 showed good binding affinity for human opioid or cannabinoid receptors. These findings have important implications for psychoactive studies with this class of compounds. PMID:21667972

Gao, Jiangtao; León, Francisco; Radwan, Mohamed M; Dale, Olivia R; Husni, Afeef S; Manly, Susan P; Lupien, Shari; Wang, Xiaoning; Hill, Robert A; Dugan, Frank M; Cutler, Horace G; Cutler, Stephen J

2011-07-22

160

Synthesis, structural characterization and biological studies of copper complexes with 2-aminobenzothiazole derivatives  

NASA Astrophysics Data System (ADS)

Novel copper complexes of 2-aminobenzothiazole derivatives were synthesized by the condensation of Knoevenagel condensate acetoacetanilide (obtained from substituted benzaldehydes and acetoacetanilide) and 2-aminobenzothiazole. They were thoroughly characterized by elemental analysis, IR, 1H NMR, UV-Vis., MS Spectra, molar conductance, magnetic moment and electrochemical studies. These spectral studies suggested that distorted square planar geometry for all the complexes. Molar conductance data and magnetic susceptibility measurements provide evidence for monomeric and neutral nature of the complexes. The electrochemical behaviour of the ligand and complexes in DMSO at 298 K was studied. The present ligand systems stabilize the unusual oxidation states of copper ion during electrolysis. Antibacterial screening of the ligands and their complexes reveal that all the complexes show higher activities than the free ligands.

Joseph, J.; Boomadevi Janaki, G.

2014-04-01

161

IR spectra of protonated benzaldehyde clusters, C7H7O+-Ln (L=Ar,N2n<=2): Ion-ligand binding motifs of the cis and trans oxonium isomers  

NASA Astrophysics Data System (ADS)

Infrared photodissociation (IRPD) spectra of mass-selected protonated benzaldehyde (C7H7O+,BZH+) and its weakly bound clusters with Ar and N2 produced in an electron impact source are recorded in the C-H and O-H stretch ranges. The experimental results are supported by ab initio and density functional calculations. Analysis of the IRPD spectrum of the BZH+ monomer is consistent with the presence of the cis and trans isomers of the oxonium ions, which is confirmed by the cluster spectra. No signature of the less stable carbenium ions is detected. Frequency shifts in the IRPD spectra of dimers and trimers provide information about the preferred intermolecular ligand binding site (?-bonding versus H-bonding) and the corresponding interaction strength. H-bonding to the OH group of the oxonium ions of BZH+ is found to be favored over ?-bonding to the aromatic ring for both Ar and N2. There are significant differences in the microsolvation structure and energetics of the cis and trans oxonium isomers of BZH+ due to the rather different acidities of their OH groups and isomer-dependent effects arising from steric hindrance. The large positive partial charge of the protonated formyl group implies that the cluster growth of the larger clusters continues by further solvation of the protonated substituent rather than the aromatic ring.

Chakraborty, Shamik; Patzer, Alexander; Dopfer, Otto

2010-07-01

162

IR spectra of protonated benzaldehyde clusters, C(7)H(7)O(+)-L(n) (L=Ar,N(2);n  

PubMed

Infrared photodissociation (IRPD) spectra of mass-selected protonated benzaldehyde (C(7)H(7)O(+),BZH(+)) and its weakly bound clusters with Ar and N(2) produced in an electron impact source are recorded in the C-H and O-H stretch ranges. The experimental results are supported by ab initio and density functional calculations. Analysis of the IRPD spectrum of the BZH(+) monomer is consistent with the presence of the cis and trans isomers of the oxonium ions, which is confirmed by the cluster spectra. No signature of the less stable carbenium ions is detected. Frequency shifts in the IRPD spectra of dimers and trimers provide information about the preferred intermolecular ligand binding site (pi-bonding versus H-bonding) and the corresponding interaction strength. H-bonding to the OH group of the oxonium ions of BZH(+) is found to be favored over pi-bonding to the aromatic ring for both Ar and N(2). There are significant differences in the microsolvation structure and energetics of the cis and trans oxonium isomers of BZH(+) due to the rather different acidities of their OH groups and isomer-dependent effects arising from steric hindrance. The large positive partial charge of the protonated formyl group implies that the cluster growth of the larger clusters continues by further solvation of the protonated substituent rather than the aromatic ring. PMID:20687650

Chakraborty, Shamik; Patzer, Alexander; Dopfer, Otto

2010-07-28

163

Trypanocidal nitroimidazole derivatives: relationships among chemical structure and genotoxic activity.  

PubMed

Human American trypanosomiasis is resurgent in Latin Americans, and new drugs are urgently required as current medications suffer from a number of drawbacks. Some nitroheterocycles have been demonstrated to exert a potent activity against trypanosomes. However, host toxicity issues halted their development as trypanocides. As part of the efforts to develop new compounds in order to treat parasitic infections, it is important to define their structure-activity relationship. In this study, 5-nitromegazol and two of its analogues, 4-nitromegazol, and 1-methyl-5-nitro-2-imidazolecarboxaldehyde 5-nitroimidazole-thiosemicarbazone, were tested and compared for in vitro induction of DNA damage in human leukocytes by the comet assay, performed at different pHs to better identify the types of damage. Specific oxidatively generated damage to DNA was also measured by using the comet assay with endonucleases. DNA damage was found in 5-nitromegazol-treated cells: oxidative stress appeared as the main source of DNA damage. 4-Nitromegazol did not produce any significant effect, thus confirming that 4-nitroimidazoles isomers have no important biological activity. The 5-nitroimidazole-thiosemicarbazone induced DNA damage with a higher efficiency than 5-nitromegazol. The central role in the reduction process played by the acidic hydrazine proton present in the thiosemicarbazone group but not in the cyclic (thiadiazole) form can contribute to rationalise our results. Given its versatility, thiosemicarbazone moiety could be involved in different reactions with nitrogenous bases (nucleophilic and/or electrophilic attacks). PMID:17291457

Buschini, Annamaria; Giordani, Federica; de Albuquerque, Cristina Northfleet; Pellacani, Claudia; Pelosi, Giorgio; Rossi, Carlo; Zucchi, Tânia Maria Araújo Domingues; Poli, Paola

2007-05-15

164

Complex derivatives  

NASA Astrophysics Data System (ADS)

The intrinsic complexity of the financial derivatives market has emerged as both an incentive to engage in it, and a key source of its inherent instability. Regulators now faced with the challenge of taming this beast may find inspiration in the budding science of complex systems.

Battiston, Stefano; Caldarelli, Guido; Georg, Co-Pierre; May, Robert; Stiglitz, Joseph

2013-03-01

165

Derivatives of the triaminoguanidinium ion, 3. Multiple N-functionalization of the triaminoguanidinium ion with isocyanates and isothiocyanates  

PubMed Central

Summary 1,2,3-Triaminoguanidinium chloride was combined with benzaldehyde and hydratropic aldehyde to furnish the corresponding tris(imines), which were converted into 1,2,3-tris(benzylamino)guanidinium salts by catalytic hydrogenation in the former, and by borane reduction in the latter case. The resulting alkyl-substituted triaminoguanidinium salts underwent a threefold carbamoylation with aryl isocyanates to furnish 1,2,3-tris(ureido)guanidinium salts, while p-toluenesulfonyl isocyanate led only to a mono-ureido guanidinium salt. With aryl isothiocyanates, 3-hydrazino-1H-1,2,4-triazole-5(4H)-thione derivatives were obtained. Compounds 7a and 8 show interesting solid-state structures with intra- and intermolecular hydrogen bonds. PMID:25298792

Szabo, Jan; Karger, Kerstin; Bucher, Nicolas

2014-01-01

166

The synthesis and biological evaluation of some caffeic acid amide derivatives: E-2-cyano-(3-substituted phenyl)acrylamides.  

PubMed

A series of caffeic acid amide derivatives 2-cyano-(3-substituted phenyl)acrylamides were synthesized via Knoevenogal condensation of substituted benzaldehydes with cyanoacetamides. The structure of compound 1f was determined as E-isomer by X-ray diffractive analysis. The biological screening tests in vitro showed that compound 1b has obvious inhibitory activities against human gastric carcinoma cell line BGC-823, human nasopharyngeal carcinoma cell line KB and human hepatoma cell line BEL-7402 with IC(50) values of 5.6 microg/mL, 13.1 microg/mL and 12.5 microg/mL, respectively. Some preliminary structure-activity relationships (SAR) were also proposed which may provide a direction for further study. PMID:19272773

Zhou, Wei; Li, Hai-bo; Xia, Chun-nian; Zheng, Xian-ming; Hu, Wei-xiao

2009-04-01

167

Glycal Derivatives  

NASA Astrophysics Data System (ADS)

Glycals are unsaturated sugar derivatives in which the double bond engages the anomeric carbon atom. Such cyclic vinyl ethers are characterized by high reactivity, allowing for regio- and stereoselective transformations, directly or indirectly related to glycosylation, as well as to formation of carbon-carbon and carbon-heteroatom bonds at the anomeric center. This review provides a systematic survey of chemical synthetic methods, by which the carbon-carbon double bond is introduced next to the ring oxygen, in an endo- or exocyclic position. Some mechanistic aspects are discussed in relation to traditional methods of glycal preparation, which rely on elimination reactions. Glycal-to-glycal rearrangement and applications of organometallic chemistry and heteroatom-induced transformations for syntheses and activation of glycals are also highlighted.

Priebe, Waldemar; Fokt, Izabela; Grynkiewicz, Grzegorz

168

4-(p-Tolyl­amino)­benzaldehyde  

PubMed Central

In the title compound, C14H13NO, the dihedral angle between the aromatic rings is 66.08?(9)°. Chains are formed along the b axis through inter­molecular N—H?O hydrogen bonds. The crystal structure is further stabilized by C—H?? inter­actions. PMID:21589015

Tian, Xiao; Xie, Yong-Sheng; Zuo, Hua

2010-01-01

169

(E)-4-Nitro­benzaldehyde oxime  

PubMed Central

In the title compound, C7H6N2O3, the planes containing the CNO and ONO atoms subtend dihedral angles of 5.47?(5) and 8.31?(5)°, respectively, with the benzene ring. In the crystal structure, inter­molecular O—H?N hydrogen bonds link the mol­ecules into centrosymmetric dimers with an R 2 2(6) graph-set motif. PMID:21579179

Abbas, Asghar; Hussain, Safdar; Hafeez, Noureen; Badshah, Amir; Hasan, Aurangzeb; Lo, Kong Mun

2010-01-01

170

Di­aqua­[5,10,15,20-tetra­kis­(4-chloro­phen­yl)porphyrinato-?4 N]iron(III) tri­fluoro­methane­sulfonate–4-hy­droxy-3-meth­oxy­benzaldehyde–water (1/1/2)  

PubMed Central

In the title compound, [Fe(C44H24Cl4N4)(H2O)2](SO3CF3)·C8H8O3·2H2O, the FeIII cation is chelated by the four N atoms of the deprotonated tetra­kis­(4-chloro­tetra­phen­yl)porphyrin (TClPP) and further coordinated by two water mol­ecules in a distorted octa­hedral geometry. In the crystal, the cations, anions, 4-hy­droxy-3-meth­oxy­benzaldehyde and water mol­ecules of crystallization are linked by classical O—H?O hydrogen bonds and weak C—H?O and C—H?Cl hydrogen bonds into a three-dimensional supra­molecular architecture. The crystal packing is further stabilized by weak C—H?? inter­actions involving pyrrole and benzene rings. ?–? stacking between parallel benzene rings of adjacent 4-hy­droxy-3-meth­oxy­benzaldehyde mol­ecules is also observed, the centroid–centroid distance being 3.8003?(13)?Å. The three F atoms of the anion are disordered over two sets of sites, with a refined occupancy ratio 0.527?(12):0.473?(12). The O atom of one water mol­ecule of crystallization is also disordered over two positions in an occupancy ratio of 0.68?(5):0.32?(5). PMID:25249880

Ben Haj Hassen, Leila; Ezzayani, Khaireddine; Rousselin, Yoann; Nasri, Habib

2014-01-01

171

Complex forming competition and in-vitro toxicity studies on the applicability of di-2-pyridylketone-4,4,-dimethyl-3-thiosemicarbazone (Dp44mT) as a metal chelator.  

PubMed

Di-2-pyridylketone-4,4,-dimethyl-3-thiosemicarbazone (Dp44mT) is a potential candidate in chelation therapy as an iron chelator. This study showed that a combined treatment with 2?M easily available Fe(II), Cu(II) and Zn(II) each and 5?M Dp44mT on eight different cancer cell lines resulted in a 10-40-fold increase in the intracellular Cu content compared to control samples. The uptake of Cu and Cu-dependent cytotoxicity strictly depend on the Cu concentration of the culture medium. Even as low concentration of Dp44mT as 0.1?M can transport high amounts of copper inside the cells. The Cu accumulation and toxicity through Dp44mT can hardly be influenced by Fe. Copper uptake and toxicity triggered by 2?M extracellular Cu(II) and 5?M Dp44mT could not be influenced by Fe(II) extracellular concentrations even 50-times higher than that of Cu(II). A 50-times higher Co(II) extracellular concentration hindered the Cu(II) uptake almost completely and a 10-times higher Co(II) concentration already decreased the Dp44mT-mediated Cu toxicity. Conditional complex stability constant determinations for Dp44mT with Cu(II), Co(II), Fe(II), Ni(II) and Zn(II) revealed that the metal-to-ligand ratio is 1:1 in [Cu(II)Dp44mT] complex, while for Co(II), Fe(II) and Ni(II) is 1:2. The highest stability constant was obtained for Cu(II) (lg ?=7.08±0.05) and Co(II) (lg ?2=12.47±0.07). According to our results, Dp44mT in combination with Cu is highly toxic in vitro. Therefore, the use of Dp44mT as an iron chelator is limited if biologically available Cu is also present even at low concentrations. PMID:24176919

Gaál, Anikó; Orgován, Gábor; Polgári, Zsófia; Réti, Andrea; Mihucz, Victor G; B?sze, Szilvia; Szoboszlai, Norbert; Streli, Christina

2014-01-01

172

The volatile profiles of a rare apple (Malus domestica Borkh.) honey: shikimic acid-pathway derivatives, terpenes, and others.  

PubMed

The volatile profiles of rare Malus domestica Borkh. honey were investigated for the first time. Two representative samples from Poland (sample?I) and Spain (sample?II) were selected by pollen analysis (44-45% of Malus spp. pollen) and investigated by GC/FID/MS after headspace solid-phase microextraction (HS-SPME) and ultrasonic solvent extraction (USE). The apple honey is characterized by high percentage of shikimic acid-pathway derivatives, as well as terpenes, norisoprenoids, and some other compounds such as coumaran and methyl 1H-indole-3-acetate. The main compounds of the honey headspace were (sample?I; sample?II): benzaldehyde (9.4%; 32.1%), benzyl alcohol (0.3%; 14.4%), hotrienol (26.0%, 6.2%), and lilac aldehyde isomers (26.3%; 1.7%), but only Spanish sample contained car-2-en-4-one (10.2%). CH2 Cl2 and pentane/Et2 O 1?:?2 (v/v) were used for USE. The most relevant compounds identified in the extracts were: benzaldehyde (0.9-3.9%), benzoic acid (2.0-11.2%), terpendiol I (0.3-7.4%), coumaran (0.0-2.8%), 2-phenylacetic acid (2.0-26.4%), methyl syringate (3.9-13.1%), vomifoliol (5.0-31.8%), and methyl 1H-indole-3-acetate (1.9-10.2%). Apple honey contained also benzyl alcohol, 2-phenylethanol, (E)-cinnamaldehyde, (E)-cinnamyl alcohol, eugenol, vanillin, and linalool that have been found previously in apple flowers, thus disclosing similarity of both volatile profiles. PMID:24078598

Ku?, Piotr Marek; Jerkovi?, Igor; Tuberoso, Carlo Ignazio Giovanni; Šaroli?, Mladenka

2013-09-01

173

Spectral, redox and catalytic studies of triphenylphosphine/triphenylarsine complexes of Ru(III) with N, O donor ligands derived from 2-hydroxy-1-naphthaldehyde and primary amines  

NASA Astrophysics Data System (ADS)

A series of new mixed ligand hexacoordinated ruthenium(III) Schiff base complexes of the type [RuX 2(EPh 3) 2(LL')] (X = Cl, E = P; X = Cl or Br, E = As and LL' = anion of the Schiff bases derived from the condensation of 2-hydroxy-1-naphthaldehyde with aniline, 4-chloroaniline, 2-methyl aniline and 4-methoxy aniline) are reported. All the complexes have been characterized by analytical and spectral (IR, electronic and EPR) data. The redox behavior of the complexes has also been studied. The complexes exhibit catalytic activity in the oxidation of benzyl alcohol to benzaldehyde in the presence of N-methyl morpholine- N-oxide (NMO). An octahedral structure has been proposed for all of the complexes.

Mahalingam, V.; Karvembu, R.; Chinnusamy, V.; Natarajan, K.

2006-07-01

174

Synthesis, Characterization, Theoretical Crystal Structure, and Antibacterial Activities of Some Transition Metal Complexes of the Thiosemicarbazone (Z)-2-(pyrrolidin-2-ylidene)hydrazinecarbothioamide  

PubMed Central

Problem Statement. In Iraq like most third world countries, attempts discovered new antibiotic drugs derived from thiosemicarbazide and its metal complexes and developed the branch of applied in organic chemistry. Approach. New (Z)-2-(pyrrolidin-2-ylidene)hydrazinecarbothioamide (L) was synthesized in a good yield by the reaction of pyrrolidone with thiosemicarbazide. Co(II), Ni(II), and Cu(II) complexes of (L) were prepared and characterized by FT-IR, UV/visible spectra, 1HNMR, and CHN analyses. Moreover, charge, bond length, bond angle, twist angle, heat of formation, and steric energy were calculated by using of the ChemOffice program, and the DFT calculations for the complexes were done. The free ligand and its metal complexes were tested in vitro against several microorganisms (Staphylococcus aurous, E. coli, Proteus vulgaris, Pseudomonas, and Klebsiella pneumoniae) to assess their antimicrobial properties. Results. The study shows that these complexes have octahedral geometry; in addition, it has high activity against tested bacteria. Conclusion/Recommendations. Based on the reported results, it may be concluded that ligand acts as bidentate, neutral ligand, coordinating through one of the nitrogen and sulfur atoms. PMID:21804771

Al-Amiery, Ahmed A.; Al-Majedy, Yasmien K.; Abdulreazak, Haziem; Abood, Hussain

2011-01-01

175

Synthesis, Characterization, Theoretical Crystal Structure, and Antibacterial Activities of Some Transition Metal Complexes of the Thiosemicarbazone (Z)-2-(pyrrolidin-2-ylidene)hydrazinecarbothioamide.  

PubMed

Problem Statement. In Iraq like most third world countries, attempts discovered new antibiotic drugs derived from thiosemicarbazide and its metal complexes and developed the branch of applied in organic chemistry. Approach. New (Z)-2-(pyrrolidin-2-ylidene)hydrazinecarbothioamide (L) was synthesized in a good yield by the reaction of pyrrolidone with thiosemicarbazide. Co(II), Ni(II), and Cu(II) complexes of (L) were prepared and characterized by FT-IR, UV/visible spectra, (1)HNMR, and CHN analyses. Moreover, charge, bond length, bond angle, twist angle, heat of formation, and steric energy were calculated by using of the ChemOffice program, and the DFT calculations for the complexes were done. The free ligand and its metal complexes were tested in vitro against several microorganisms (Staphylococcus aurous, E. coli, Proteus vulgaris, Pseudomonas, and Klebsiella pneumoniae) to assess their antimicrobial properties. Results. The study shows that these complexes have octahedral geometry; in addition, it has high activity against tested bacteria. Conclusion/Recommendations. Based on the reported results, it may be concluded that ligand acts as bidentate, neutral ligand, coordinating through one of the nitrogen and sulfur atoms. PMID:21804771

Al-Amiery, Ahmed A; Al-Majedy, Yasmien K; Abdulreazak, Haziem; Abood, Hussain

2011-01-01

176

Spectroscopic studies and structure of 3-methoxy-2 -[(2,4,4,6,6-pentachloro-1,3,5,2{lambda}{sup 5},4{lambda}{sup 5},6{lambda}{sup 5}-triazatriphosphin-2-yl)oxy] benzaldehyde  

SciTech Connect

The compound called 3-methoxy-2- [(2,4,4,6,6-pentachloro-1,3,5,2{lambda}{sup 5},4{lambda}{sup 5},6{lambda}{sup 5}-triazatriphosphin-2-yl)oxy] benzaldehyde has been synthesized from the reaction of 2-hydroxy-3-methoxybenzaldehyde with hexachlorocyclotriphosphazene. It has been characterized by elemental analysis, MS, IR, {sup 1}H NMR, {sup 13}C NMR, {sup 31}P NMR and UV-visible spectroscopic techniques. The structure of the title compound has been determind by X-ray analysis. Crystals are orthorhombic, space group P2{sub 1}2{sub 1}2{sub 1}, Z = 4, a = 7.705(1), b = 12.624(1), c = 17.825(2) A, R{sub 1} = 0.0390 and wR{sub 2} = 0.1074 [I > 2{sigma}(I)], respectively.

Oezay, H.; Yildiz, M., E-mail: myildiz@comu.edu.tr [Canakkale Onsekiz Mart University, Department of Chemistry, Faculty of Science and Arts (Turkey); Uenver, H.; Durlu, T. N. [Ankara University, Department of Physics, Faculty of Science (Turkey)] [Ankara University, Department of Physics, Faculty of Science (Turkey)

2013-01-15

177

Higher order fractional derivatives  

E-print Network

Based on the Liouville-Weyl definition of the fractional derivative, a new direct fractional generalization of higher order derivatives is presented. It is shown, that the Riesz and Feller derivatives are special cases of this approach.

Richard Herrmann

2009-06-12

178

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)

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, ? = 101.779(3)°, 104.926(2)°, for I and II, respectively. An extensive two-dimensional network of N-H⋯N hydrogen bonds and ?-ring interactions are responsible for crystal stabilization in both structures.

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

2014-12-01

179

Synthesis, characterization and thermal studies of binary and/or mixed ligand complexes of Cd(II), Cu(II), Ni(II) and Co(III) based on 2-(Hydroxybenzylidene) thiosemicarbazone: DNA binding affinity of binary Cu(II) complex.  

PubMed

A new series of metal complexes of Cd(II), Cu(II), Ni(II) and Co(III) with Schiff base ligand, H(2)L, 2-(Hydroxybenzylidene) thiosemicarbazone were synthesized. The mixed ligand complexes were prepared by using glycine (Gly), 2-aminopyridine (2-Ampy) and 1,10-phenanthroline (Phen) as secondary ligands. The structure of these complexes was identified and confirmed by elemental analysis, molar conductivity, UV-Vis, FT-IR and (1)H NMR spectroscopy and magnetic moment measurements as well as TG-DSC technique. The discussions of the prepared complexes indicate that the ligand behaves as a monoanionic tridentate ligand through ONS donor sites. Thermal studies suggested a mechanism for the degradation of the metal complexes as a function of temperature supporting the chelation modes and showed the possibility of obtaining new complexes pyrolytically in the solid state which cannot be synthesized from the solution. The absorption studies support that the binary Cu(II) complex exhibits a significant binding affinity to HS-DNA through intercalative mode. PMID:22446784

Saif, M; Mashaly, Mahmoud M; Eid, Mohamed F; Fouad, R

2012-06-15

180

Absolute Time Derivatives  

E-print Network

A four dimensional treatment of nonrelativistic space-time gives a natural frame to deal with objective time derivatives. In this framework some well known objective time derivatives of continuum mechanics appear as Lie-derivatives. Their coordinatized forms depends on the tensorial properties of the relevant physical quantities. We calculate the particular forms of objective time derivatives for scalars, vectors, covectors and different second order tensors from the point of view of a rotating observer. The relation of substantial, material and objective time derivatives is treated.

T. Matolcsi; P. Van

2006-08-31

181

Generation of 2'-deoxyadenosine N6-aminyl radicals from the photolysis of phenylhydrazone derivatives.  

PubMed

Nitrogen-centered radicals are major species generated by the addition of hydroxyl radicals and the one-electron oxidation of adenine derivatives. Aminyl radicals are also generated in the decomposition of adenine chloramines upon reaction of hypochlorite. Here, we report the photochemistry of modified 2'-deoxyadenosine (dAdo) containing photoactive hydrazone substituents as a model to investigate the chemistry of dAdo N(6)-aminyl radicals. Derivatives of dAdo containing a phenylhydrazone moiety at N6 displayed UV absorption between 300 and 400 nm. Upon UV photolysis in the presence of a H-donor, that is, glutathione, two major products were formed, dAdo and benzaldehyde, indicating efficient homolytic cleavage to dAdo N(6)-aminyl radicals and benzylidene iminyl radicals. dAdo N(6)-phenylhydrazone was photolyzed in the presence of a molar excess of nonmodified dAdo to mimic the reactions taking place in DNA, and the major photoproducts were identified by high-performance liquid chromatography, mass spectrometry, and nuclear magnetic resonance. The formation of 2-(benzylideneamino)-2'-deoxyadenosine as well as a more extensive oxidation product may be explained by the recombination of initial dAdo N(6)-aminyl and benzylidene iminyl radicals. The formation of 2'-deoxyinosine may be explained by hydrolytic deamination of dAdo N(6)-aminyl radicals. Interestingly, a dimeric product containing two dAdo moieties was identified in the photolysis mixture. The present studies demonstrate the ability of dAdo N(6)-aminyl radicals to undergo H-abstraction to give dAdo, deamination to give 2'-deoxyinosine, and addition to the adenine moiety to give dimers. PMID:20000474

Kuttappan-Nair, Vandana; Samson-Thibault, Francois; Wagner, J Richard

2010-01-01

182

Partial Derivatives: Geometric Visualization  

NSDL National Science Digital Library

This write-pair-share activity presents Calculus III students with a worksheet containing several exercises that require them to find partial derivatives of functions of two variables. Afterwards, a series of Web-based animations are used to illustrate the surface of each function, the path of the indicated partial derivative for a specified value of the variable and the value of the derivative at each point along the path.

Rutledge, James

183

A new chitosan biopolymer derivative as metal-complexing agent: synthesis, characterization, and metal(II) ion adsorption studies.  

PubMed

In this study, a new chitosan biopolymer derivative (CTSL) has been synthesized by anchoring a new vanillin-based complexing agent or ligand, namely 4-hydroxy-3-methoxy-5-[(4-methylpiperazin-1-yl)methyl] benzaldehyde, (L) with chitosan (CTS) by means of condensation. The new material was characterized by elemental (CHN), spectral (FTIR and solid state (13)C NMR), thermal (TG-DTA and DSC), structural (powder XRD), and morphological (SEM) analyses. The CTSL was employed to study the equilibrium adsorption of various metal ions, namely, Mn(II), Fe(II), Co(II), Cu(II), Ni(II), Cd(II), and Pb(II), as functions of pH of the solutions. Its kinetics of adsorption was evaluated utilizing the pseudo first order and pseudo second order equation models and the equilibrium data were analyzed by Langmuir isotherm model. The CTSL shows good adsorption capacity for metal ions studied in the order Cu(II)>Ni(II)>Cd(II)> or =Co> or =Mn(II)>Fe(II)>Pb(II) in all studied pH ranges due to the presence of many coordinating moieties present in it. PMID:20708730

Krishnapriya, K R; Kandaswamy, M

2010-09-23

184

The Dangers of Derivatives.  

ERIC Educational Resources Information Center

Heavy investment in derivatives, whose value derives from the price movement of some underlying security, has meant heavy losses for some colleges and universities despite the fact that institutional investors are required to assure that they understand the risks of such investment. (MSE)

Blumenstyk, Goldie

1994-01-01

185

Partial Derivative Visualization Gallery  

NSDL National Science Digital Library

This resource is a small gallery of demos for illustrating partial derivatives geometrically. These animations can be used by instructors in a classroom setting or by students to aid in acquiring a visualization background for partial derivatives. Two file formats, gif and QuickTime files are used for the animations which can be downloaded.

Roberts, Lila F.

2004-11-11

186

The Partial Derivative Machine  

NSDL National Science Digital Library

Research has shown that students struggle to understand the use of partial derivatives in thermodynamics. We have designed an apparatus, which we have called a Partial Derivative Machine, that serves as a mechanical analogue of a thermodynamic system. Using this device, students have a tangible way to wrestle with issues related to partial derivatives and thermodynamics, such as which variables are held fixed, how many variables are independent, and how energy can be added to a system. In this paper, we present a description of the apparatus, an introduction to the associated activities, and an overview of how this apparatus can be connected to thermodynamic systems.

Sherer, Grant; Kustusch, Mary B.; Manogue, Corinne A.; Roundy, David J.

2014-01-31

187

Coordination of Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II), Pd(II) and Pt(II) with 2,5-hexanedione bis(thiosemicarbazone), HBTS: Crystal structure of cis-[Pd(HBTS)]Cl2 and 1-(2,5-dimethyl-1H-pyrrol-yl)-thiourea  

NASA Astrophysics Data System (ADS)

Metal complexes of Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, Pd2+ or Pt2+ with 2,5-hexanedione bis(thiosemicarbazone), HBTS; have been prepared and spectroscopically investigated. The empirical formulae of the complexes were suggested based on the elemental analysis. Single crystal of Pd(II) has been solved to be cis-form of square-planar geometry by the X-ray crystallography. 1H and 13C NMR spectra have been recorded for HBTS, Zn(II), Cd(II), Hg(II), Pd(II) and Pt(II) complexes, in DMSO-d6, showing the mode of chelation. The ligand acts as a neutral or a binegative tetradentate (N2S2) or neutral bidentate on the basis of FT-IR. The magnetic moments and electronic spectra provide information about the geometry of the complexes which supported by calculating the ligand field parameters for the Co(II) and Fe(III) complexes. The Ni(II) complex has subnormal magnetic moment (0.71 BM) indicative of a mixed stereochemistry of square-planar and tetrahedral structure. [Cu(HBTS-2H)] measured 0.93 BM indicating high interaction between the copper centers. The ligand may be ordered at the top of the spectrochemical series which giving high ligand field splitting energy (10Dq = 17,900 cm-1 for Co2+ complex). The mass spectra of some complexes proved their stable chemical formulae while the TGA depicts the degradation steps and the final residue. In evaporating the mother liquor during the preparation of HBTS, new compound is obtained naming 1-(2,5-dimethyl-1H-pyrrol-yl)thiourea and its crystal was solved.

Jeragh, Bakir; El-Asmy, Ahmed A.

2014-09-01

188

Derivative Matching Game  

NSDL National Science Digital Library

Once again, the Mathematical Association of America has struck instructional gold with this latest gem from their online collection of resources for mathematics educators. Created by Barbara Margolius, this derivative matching game presents users with a game board showing graphs of functions on cards. Essentially, the goal of the game is to match the functions with their derivatives. Visitors can begin by reading an overview of the game, along with some brief instructions, and then they should dive right in. The game can also be customized to match functions with just first derivatives or both first and second derivatives. Mathematics educators will have a lot of fun with this one, and even the mathematically uncertain can be drawn into the fold with this easy to use resource.

2009-05-29

189

Derivative Matching Game  

NSDL National Science Digital Library

Once again, the Mathematical Association of America has struck instructional gold with this latest gem from their online collection of resources for mathematics educators. Created by Barbara Margolius, this derivative matching game presents users with a game board showing graphs of functions on cards. Essentially, the goal of the game is to match the functions with their derivatives. Visitors can begin by reading an overview of the game, along with some brief instructions, and then they should dive right in. The game can also be customized to match functions with just first derivatives or both first and second derivatives. Mathematics educators will have a lot of fun with this one, and even the mathematically uncertain can be drawn into the fold with this easy to use resource.

190

Credit derivatives in Brazil  

E-print Network

The amounts outstanding of credit derivatives have grown exponentially over the past years, and these financial intruments that allow market participants to trade credit risk have become very popular in Europe and in the ...

Rüther, Henrique

2007-01-01

191

Teaching Cournot without Derivatives.  

ERIC Educational Resources Information Center

Presents a simple technique for teaching the Cournot model to first-year microeconomic students. Involves demonstrating, without the use of derivatives, that out of all rectangles with a common perimeter, the square has the greatest area. (RLH)

Dufwenberg, Martin

2001-01-01

192

Cyclodextrin derivative of hyaluronan  

Microsoft Academic Search

Conversion of hyaluronan (HA) to its ?-cyclodextrin derivative (HA-?-CD) was accomplished by direct coupling of ?-cyclodextrin (?-CD) molecules with carboxylic acid groups of the HA macromolecule. The intermolecular dehydration, yielding the HA-?-CD derivative, was performed by the action of diethyl azodicarboxylate and triphenylphosphine under mild, neutral conditions. The physico-chemical characteristics of the novel (bio)material, determined both in solution and solid

L. Šoltés; R. Mendichi; E. Machovà; B. Steiner; J. Alföldi; V. Sasinkovà; S. Bystrický; K. Balog

1999-01-01

193

Myeloid derived suppressor cells  

PubMed Central

The goal of achieving measurable response with cancer immunotherapy requires counteracting the immunosuppressive characteristics of tumors. One of the mechanisms that tumors utilize to escape immunosurveillance is the activation of myeloid derived suppressor cells (MDSCs). Upon activation by tumor-derived signals, MDSCs inhibit the ability of the host to mount an anti-tumor immune response via their capacity to suppress both the innate and adaptive immune systems. Despite their relatively recent discovery and characterization, anti-MDSC agents have been identified, which may improve immunotherapy efficacy. PMID:23734336

Waldron, Todd J.; Quatromoni, Jon G.; Karakasheva, Tatiana A.; Singhal, Sunil; Rustgi, Anil K.

2013-01-01

194

Derivatives of tetrodecamycin.  

PubMed

The derivatives of tetrodecamycin (1), being introduced acyl, carbamoyl and alkyl groups at 14-hydroxyl group and modified at exo-methylene group, were synthesized and evaluated on their antibacterial activities. Although 14-O-substituted tetrodecamycins (3 approximately 19) showed weak activity against Pasteurella piscicida, they were more active against Gram-positive bacteria than 1. Among them, 15 showed approximately 10-fold higher activity than 1. The derivatives (20 approximately 23) modified at 4 or 5 positions had moderate antibacterial activity. The absolute structure of 4(R),5-dibromotetrodecamycin (23) was determined by X-ray crystallographic analysis. PMID:8557576

Tsuchida, T; Iinuma, H; Nakamura, K T; Nakamura, H; Sawa, T; Hamada, M; Takeuchi, T

1995-11-01

195

Telomeric 30 Overhangs Derive  

E-print Network

Telomeric 30 Overhangs Derive from Resection by Exo1 and Apollo and Fill-In by POT1b-Associated CST and main- tenance of mammalian telomeres, but its synthesis must be regulated to avoid excessive resection of the 50 end, which could cause telomere shortening. How this balance is achieved in mammals has not been

de Lange, Titia

196

Biotechnology and derived products  

Technology Transfer Automated Retrieval System (TEKTRAN)

Microorganisms able to infect and kill insect pests, metabolites from plants and microorganisms, and transgenic crops are biotechnologically derived products that are being promoted for use to control insect pests in lieu of chemical insecticides. Products based on these technologies effectively co...

197

Fractional Derivative Cosmology  

E-print Network

The degree by which a function can be differentiated need not be restricted to integer values. Usually most of the field equations of physics are taken to be second order, curiosity asks what happens if this is only approximately the case and the field equations are nearly second order. For Robertson-Walker cosmology there is a simple fractional modification of the Friedman and conservation equations. In general fractional gravitational equations similar to Einstein's are hard to define as this requires fractional derivative geometry. What fractional derivative geometry might entail is briefly looked at and it turns out that even asking very simple questions in two dimensions leads to ambiguous or intractable results. A two dimensional line element which depends on the Gamma-function is looked at.

Mark D. Roberts

2009-09-07

198

Insulin-derived amyloidosis  

PubMed Central

Amyloidosis is the term for diseases caused by the extracellular deposition of insoluble polymeric protein fibrils in tissues and organs. Insulin-derived amyloidosis is a rare, yet significant complication of insulin therapy. Insulin-derived amyloidosis at injection site can cause poor glycemic control and increased insulin dose requirements because of the impairment in insulin absorption, which reverse on change of injection site and/or excision of the mass. This entity should be considered and assessed by histopathology and immunohistochemistry, in patients with firm/hard local site reactions, which do not regress after cessation of insulin injection at the affected site. Search strategy: PubMed was searched with terms “insulin amyloidosis”. Full text of articles available in English was reviewed. Relevant cross references were also reviewed. Last search was made on October 15, 2014.

Gupta, Yashdeep; Singla, Gaurav; Singla, Rajiv

2015-01-01

199

[Synthesis of porphyrin derivatives].  

PubMed

This paper presents the preparation of eleven 2, 4 or 6, 7-substituted porphyrine derivatives II-XII from I or diethyl ether of IV. The effects of these compounds, with irradiation, on DNA synthesis in L1210 cells were studied. The results showed that (1) all of these compounds were effective while (2) Va or Vb, VI and VII were more effective. PMID:1839589

Lu, Y H; Liu, F C

1991-01-01

200

Computation of Mie derivatives.  

PubMed

Analytical expressions are obtained for the derivatives of Mie scattering coefficients with respect to the electrical radius of the spherical scattering particle, and to the relative permittivity and permeability of both the particle and the surrounding medium. Their corresponding approximate expressions are developed to avoid numerical overflow based on the logarithmic derivative of Riccati-Bessel functions. The analytical expressions have been verified by comparing their results with those calculated by analytical expressions developed by Mathematica. Compared with the numerical derivative, the analytical expressions and approximate expressions show a higher accuracy and are 2.0 and 2.8 times, respectively, faster in the case of a single magnetodielectric sphere. Generally, for spheres with an electrical radius in a large range, the approximate expressions can yield acceptable accuracy and computation time up to a high order. This work can be used in the design of nonmetallic metamaterials, and in the retrieval of aerosol properties from remote sensing data. An example calculation is given for the design of an optical, all-dielectric, mu-negative metamaterial consisting of a simple cubic array of tellurium nanoparticles. PMID:23852216

Li, Yang; Bowler, Nicola

2013-07-10

201

4-Eth­oxy-3-meth­oxy­benzaldehyde  

PubMed Central

In the title compound, C10H12O3, all non-H atoms are approximately coplanar, with an r.m.s. deviation of 0.046?Å. In the crystal, very weak C—H?O inter­actions link the mol­ecules into sheets parallel to (101). PMID:24454190

Leka, Zorica; Novakovi?, Sladjana B.; Bogdanovi?, Goran A.; Muškinja, Jovana; Vuki?evi?, Rastko D.

2013-01-01

202

3-Methoxy-4-(4-nitro­benz­yloxy)­benzaldehyde  

PubMed Central

In the title compound, C15H13NO5, the vanillin group makes a dihedral angle of 4.95?(8)° with the benzene ring of the nitro­benzene group. The packing is stabilized by weak, non-classical inter­molecular C—H?O inter­actions which link mol­ecules into chains running along the c axis. PMID:21581269

Li, Mei; Chen, Xin

2008-01-01

203

Synthesis of tetrahydrobenzimidazole derivatives  

Microsoft Academic Search

O! l| 3,5,5-Trimethyl- 7-ketotetrahydro benzimidazole (III) was similarly obtained from 5,5-dimethylcycl ohexane-l,2,3-tri one monophenylhydraz one. Treatment of the sodium derivative of III with bromoacetophenone and then with ammonium acetate in acetic acid gave the previously unknown 2,8,8-trimethyl- 5-phenyl7,8-dihydro-9H-p yrazino [3,2,1-h,i]benzimidazole (IV), which was isolated as the picrate. H3C\\\\ ~.~ tlaC CH 3

V. I. Shvedov; L. B. Altukhova; A. N. Grinev

1972-01-01

204

Distinct mechanisms of cell-kill by triapine and its terminally dimethylated derivative Dp44mT due to a loss or gain of activity of their copper(II) complexes.  

PubMed

Triapine, currently being evaluated as an antitumor agent in phase II clinical trials, and its terminally dimethylated derivative Dp44mT share the ?-pyridyl thiosemicarbazone backbone that functions as ligands for transition metal ions. Yet, Dp44mT is approximately 100-fold more potent than triapine in cytotoxicity assays. The aims of this study were to elucidate the mechanisms underlying their potency disparity and to determine their kinetics of cell-kill in culture to aid in the formulation of their clinical dosing schedules. The addition of Cu(2+) inactivated triapine in a 1:1 stoichiometric fashion, while it potentiated the cytotoxicity of Dp44mT. Clonogenic assays after finite-time drug-exposure revealed that triapine produced cell-kill in two phases, one completed within 20 min that caused limited cell-kill, and the other occurring after 16 h of exposure that produced extensive cell-kill. The ribonucleotide reductase inhibitor triapine at 0.4 ?M caused immediate complete arrest of DNA synthesis, whereas Dp44mT at this concentration did not appreciably inhibit DNA synthesis. The inhibition of DNA synthesis by triapine was reversible upon its removal from the medium. Cell death after 16 h exposure to triapine paralleled the appearance of phospho-(?)H2AX, a marker of DNA double-strand breaks induced by collapse of DNA replication forks after prolonged replication arrest. In contrast to triapine, Dp44mT produced robust cell-kill within 1h in a concentration-dependent manner. The short-term action of both agents was prevented by thiols, indicative of the involvement of reactive oxygen species. The time dependency in the production of cell-kill by triapine should be considered in treatment regimens. PMID:25130544

Ishiguro, Kimiko; Lin, Z Ping; Penketh, Philip G; Shyam, Krishnamurthy; Zhu, Rui; Baumann, Raymond P; Zhu, Yong-Lian; Sartorelli, Alan C; Rutherford, Thomas J; Ratner, Elena S

2014-10-01

205

Acquiring Knowledge of Derived Nominals and Derived Adjectives in Context  

ERIC Educational Resources Information Center

Purpose: This research investigated children's ability to acquire semantic and syntactic knowledge of derived nominals and derived adjectives in the context of short passages. The study also investigated the relation of morphological awareness and the ability to acquire knowledge of derived words in context. Method: A total of 106 children in…

Marinellie, Sally A.; Kneile, Lynn A.

2012-01-01

206

Alcohol dehydrogenases from Scheffersomyces stipitis involved in the detoxification of aldehyde inhibitors derived from lignocellulosic biomass conversion.  

PubMed

Aldehyde inhibitors such as furfural and 5-hydroxymethylfurfural (HMF) are generated from biomass pretreatment. Scheffersomyces stipitis is able to reduce furfural and HMF to less toxic furanmethanol and furan-2,5-dimethanol; however, the enzymes involved in the reductive reaction still remain unknown. In this study, transcription responses of two known and five putative alcohol dehydrogenase genes from S. stipitis were analyzed under furfural and HMF stress conditions. All the seven alcohol dehydrogenase genes were also cloned and overexpressed for their activity analyses. Our results indicate that transcriptions of SsADH4 and SsADH6 were highly induced under furfural and HMF stress conditions, and the proteins encoded by them exhibited NADH- and/or NADPH-dependent activities for furfural and HMF reduction, respectively. For furfural reduction, NADH-dependent activity was also observed in SsAdh1p and NAD(P)H-dependent activities were also observed in SsAdh5p and SsAdh7p. For HMF reduction, NADPH-dependent activities were also observed in SsAdh5p and SsAdh7p. SsAdh4p displayed the highest NADPH-dependent specific activity and catalytic efficiency for reduction of both furfural and HMF among the seven alcohol dehydrogenases. Enzyme activities of all SsADH proteins were more stable under acidic condition. For most SsADH proteins, the optimum temperature for enzyme activities was 30 °C and more than 50 % enzyme activities remained at 60 °C. Reduction activities of formaldehyde, acetaldehyde, isovaleraldehyde, benzaldehyde, and phenylacetaldehyde were also observed in some SsADH proteins. Our results indicate that multiple alcohol dehydrogenases in S. stipitis are involved in the detoxification of aldehyde inhibitors derived from lignocellulosic biomass conversion. PMID:23912116

Ma, Menggen; Wang, Xu; Zhang, Xiaoping; Zhao, Xianxian

2013-09-01

207

The Antioxidant Activity of New Coumarin Derivatives  

PubMed Central

The antioxidant activity of two synthesized coumarins namely, N-(4,7-dioxo-2- phenyl-1,3-oxazepin-3(2H,4H,7H)-yl)-2-(2-oxo-2H-chromen-4-yloxy)acetamide 5 and N-(4-oxo-2-phenylthiazolidin-3-yl)-2-(2-oxo-2H-chromen-4-yloxy)acetamide 6 were studied with the DPPH, hydrogen peroxide and nitric oxide radical methods and compared with the known antioxidant ascorbic acid. Compounds 5 and 6 were synthesized in a good yield from the addition reaction of maleic anhydride or mercaptoacetic acid to compound 4, namely N?-benzylidene-2-(2-oxo-2H-chromen-4-yloxy)acetohydrazide. Compound 4 was synthesized by the condensation of compound 3, namely 2-(2-oxo-2H-chromen-4-yloxy) acetohydrazide, with benzaldehyde. Compound 3, however, was synthesized from the addition of hydrazine to compound 2, namely ethyl 2-(2-oxo-2H-chromen-4-yloxy)acetate, which was synthesized from the reaction of ethyl bromoacetate with 4-hydroxycoumarin 1. Structures for the synthesized coumarins 2–6 are proposed on the basis of spectroscopic evidence. PMID:22016624

Kadhum, Abdul Amir H.; Al-Amiery, Ahmed A.; Musa, Ahmed Y.; Mohamad, Abu Bakar

2011-01-01

208

The antioxidant activity of new coumarin derivatives.  

PubMed

The antioxidant activity of two synthesized coumarins namely, N-(4,7-dioxo-2- phenyl-1,3-oxazepin-3(2H,4H,7H)-yl)-2-(2-oxo-2H-chromen-4-yloxy)acetamide 5 and N-(4-oxo-2-phenylthiazolidin-3-yl)-2-(2-oxo-2H-chromen-4-yloxy)acetamide 6 were studied with the DPPH, hydrogen peroxide and nitric oxide radical methods and compared with the known antioxidant ascorbic acid. Compounds 5 and 6 were synthesized in a good yield from the addition reaction of maleic anhydride or mercaptoacetic acid to compound 4, namely N'-benzylidene-2-(2-oxo-2H-chromen-4-yloxy)acetohydrazide. Compound 4 was synthesized by the condensation of compound 3, namely 2-(2-oxo-2H-chromen-4-yloxy) acetohydrazide, with benzaldehyde. Compound 3, however, was synthesized from the addition of hydrazine to compound 2, namely ethyl 2-(2-oxo-2H-chromen-4-yloxy)acetate, which was synthesized from the reaction of ethyl bromoacetate with 4-hydroxycoumarin 1. Structures for the synthesized coumarins 2-6 are proposed on the basis of spectroscopic evidence. PMID:22016624

Kadhum, Abdul Amir H; Al-Amiery, Ahmed A; Musa, Ahmed Y; Mohamad, Abu Bakar

2011-01-01

209

Radioactively labelled porphyrin derivatives  

NASA Astrophysics Data System (ADS)

Radioactive labelling of guanidine-bearing tetraphenylporphyrin and Dy—texaphyrin with selected radionuclides (166Ho and 90Y) is described. A basic characterisation of studied porphyrin and texaphyrin, including their behaviour in a wide range of pH values and data on holmium and yttrium complexation with these compounds was probed using UV-VIS absorption spectrometry. The labelling yield of these macrocyclic molecules depends on the pH of the reaction mixture, metal: ligand ratio and time of incubation. Optimal reaction conditions for formation of porphyrin and texaphyrin radioactive complexes were determined by thin layer chromatography with the detection of ?- activity. The ability of porphyrin derivatives to bind anions was examined as well. Our experiments were focused on perrhenate ion (ReO4 -) because radiopharmaceuticals labelled with isotopes 186Re and 188Re play an important role in therapy of numerous tumour diseases. The possibility of applying ReO4 - anion directly for labelling purposes, without the necessity of its reduction to lower oxidation state, was not proved.

Koní?ová, R.; Ernestová, M.; Jedináková-K?ížová, V.; Král, V.

2003-01-01

210

Vaccine-derived polioviruses.  

PubMed

The attenuated oral poliovirus vaccine (OPV) has many properties favoring its use in polio eradication: ease of administration, efficient induction of intestinal immunity, induction of durable humoral immunity, and low cost. Despite these advantages, OPV has the disadvantage of genetic instability, resulting in rare and sporadic cases of vaccine-associated paralytic poliomyelitis (VAPP) and the emergence of genetically divergent vaccine-derived polioviruses (VDPVs). Whereas VAPP is an adverse event following exposure to OPV, VDPVs are polioviruses whose genetic properties indicate prolonged replication or transmission. Three categories of VDPVs are recognized: (1) circulating VDPVs (cVDPVs) from outbreaks in settings of low OPV coverage, (2) immunodeficiency-associated VDPVs (iVDPVs) from individuals with primary immunodeficiencies, and (3) ambiguous VDPVs (aVDPVs), which cannot be definitively assigned to either of the first 2 categories. Because most VDPVs are type 2, the World Health Organization's plans call for coordinated worldwide replacement of trivalent OPV with bivalent OPV containing poliovirus types 1 and 3. PMID:25316847

Burns, Cara C; Diop, Ousmane M; Sutter, Roland W; Kew, Olen M

2014-11-01

211

Deriving bedform phase diagrams  

NSDL National Science Digital Library

Students prepare for this activity by working with a unidirectional flume with a sand bed. We adjust water depth, flow velocity, and channel slope to achieve a range of bed states, in an effort for them to understand the controls on bedforms. This portion of the activity could be done in lecture or via another exercise that makes use of digital video of actual experiments. The activity itself is a jigsaw: students form groups of three, each group responsible for plotting depth vs. velocity plots of bedform state for a single sand grain size range (0.10-0.14 mm, 0.5-0.64 mm, and 1.3-1.8 mm). These data are provided to them as Excel files and the data were directly 'stolen' from the original depth vs. velocity plots in Middleton and Southard (1984), Mechanics of Sediment Movement, SEPM Short Course Number 3. Datathief software (available free on the web) was used to steal the data. The data are arranged in columns: depth, velocity, and bedform type. Students must plot each of the different bedform types with a different symbol, then they have to define field boundaries. It is critical that they have never seen the original plots in their textbook. The goal is for them to derive them on their own, not to regurgitate what is in their textbook or elsewhere. After they complete their plots for each grain size range, the groups re-arrange themselves into groups of three with one representative from each of the grain size groups. They then must try to evaluate the effects of changing grain size on bedform state. Finally, after completing the exercise, the bedform analysis is linked to the cross stratification that is produced under conditions of high sediment fallout rates and the given bed state. The activity gives students practice working with realistic datasets, exposure to the role of physical modeling in sedimentary geology, and a chance to plot and interpret real data. Furthermore, it really solidifies the link between cross stratification and its dynamic interpretation from the rock record.

Tom Hickson

212

CHITOSAN DERIVATIVES FOR TISSUE ENGINEERING.  

E-print Network

??Chitosan, a naturally occurring polysaccharide, and its derivatives have been widely explored for biomedical applications due to their biocompatibility and biodegradability. In our studies, we… (more)

Qiu, Yongzhi

2008-01-01

213

Limits and Derivatives: The Derivative as a Function  

NSDL National Science Digital Library

Sketch the graph of the derivative of a geometrically represented function;Explain the correspondence between the sign of the derivative on an interval and the monotonicity of the function on that interval. Classify the basic ways in which a function may fail to be differentiable.

Freeze, Michael

2003-01-22

214

Cellulose Derivatives Derived From Pulp and Paper Mill Sludge  

Microsoft Academic Search

Cellulose derivatives were produced from the cellulose fraction of pulp and paper mill sludge. The raw primary sludge was reacted under conventional cellulose derivatization conditions and the modified cellulose was isolated, in most cases, by dissolution in a suitable solvent. The cellulose derivatives produced were cellulose nitrate, cellulose acetate, carboxymethylcellulose, hydroxyethylcellulose, and methylcellulose. These compounds were characterized by Fourier transform

David G. Barkalow; Raymond A. Young

1985-01-01

215

Alternative algebras admitting derivations with invertible values and invertible derivations  

NASA Astrophysics Data System (ADS)

We prove an analogue of the Bergen-Herstein-Lanski theorem for alternative algebras: describe all alternative algebras that admit derivations with invertible values. We also prove an analogue of Moens' theorem for alternative algebras (a finite-dimensional alternative algebra over a field of characteristic zero is nilpotent if and only if it admits an invertible Leibniz derivation).

Kaygorodov, I. B.; Popov, Yu S.

2014-10-01

216

Elementary derivation of Kepler's laws  

Microsoft Academic Search

A simple derivation of all three so-called Kepler laws is presented in which the orbits, bound and unbound, follow directly and immediately from conservation of energy and angular momentum. The intent is to make this crowning achievement of Newtonian mechanics easily accessible to students in introductory physics courses. The method is also extended to simplify the derivation of the Rutherford

Erich Vogt

1996-01-01

217

Inflation Derivatives L. P. Hughston  

E-print Network

Inflation Derivatives L. P. Hughston Department of Mathematics King's College London The Strand (0)207 848 2855 Abstract. A general theory for the pricing and hedging of inflation The purpose of this note is to outline briefly a general model of inflation and inflation-linked derivatives

Macrina, Andrea

218

12 CFR 563.172 - Financial derivatives.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Financial derivatives. 563.172 Section 563.172 Banks...Management Policies § 563.172 Financial derivatives. (a) What is a financial derivative? A financial derivative is a...

2010-01-01

219

Elevation Derivatives for National Applications  

USGS Publications Warehouse

The Elevation Derivatives for National Applications (EDNA) project is a multi-agency effort to develop standard topographically derived layers for use in hydrologic and environmental modeling. The EDNA takes advantage of the seamless and filtered characteristics for the National Elevation Dataset (NED) to create a hydrologically conditioned Digital Elevation Model (DEM) useful for modeling applications. The goals of the project are to create a hydrologically conditioned DEM and systematically extract a set of standard derivatives that can be used to facilitate data integration with other U.S. Geological Survey (USGS) framework data sets such as the National Hydrography Dataset (NHD) and the Watershed Boundaries Dataset (WBD).

U.S. Geological Survey

2005-01-01

220

Quinazoline derivatives: synthesis and bioactivities  

PubMed Central

Owing to the significant biological activities, quinazoline derivatives have drawn more and more attention in the synthesis and bioactivities research. This review summarizes the recent advances in the synthesis and biological activities investigations of quinazoline derivatives. According to the main method the authors adopted in their research design, those synthetic methods were divided into five main classifications, including Aza-reaction, Microwave-assisted reaction, Metal-mediated reaction, Ultrasound-promoted reaction and Phase-transfer catalysis reaction. The biological activities of the synthesized quinazoline derivatives also are discussed. PMID:23731671

2013-01-01

221

Radioactive stilbene derivatives in radioimmunoassay  

SciTech Connect

Novel radioactive stilbene derivatives marked with iodine 125 or 131 possessing an iodine acceptor group and marked with iodine 125 or 131 and their preparation and antigens obtained therefrom and a process for preparing said antigens.

Jouquey, A.; Touyer, G.

1985-07-16

222

On Derivation of Goldman Bracket  

E-print Network

In this paper, we derive Goldman-type bracket for traces of monodromy matrices of flat connections on a compact Riemann surface for $G_{2}$ gauge group. As a by-product, we give an alternative derivation of known Goldman bracket for classical gauge groups $GL(n,\\mathbb{R})$, $SL(n,\\mathbb{R})$, $U(n)$, $SU(n)$, $Sp(2n,\\mathbb{R})$ and $SO(n)$.

S. Hasibul Hassan Chowdhury

2013-10-16

223

Organic derivatives of zirconium phosphate  

E-print Network

ORGANIC DERIVATIVES OF ZIRCONIUM PHOSPHATE A Thesis by STEVEN BERYL FINE Submitted to the Graduate College of Texas AAM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1980 Major Subject...: Chemistry ORGANIC DERIVATIVES OF ZIRCONIUM PHOSPHATE A Thesis by STEVEN BERYL FINE Approved as to style and content by: Dr. A raham Clearfield (c irman) Dr. Kurt Irgolic (member) 4~~@4 Dr. Martha Scott (member) Dr. C. S. Giam (department head...

Fine, Steven Beryl

2012-06-07

224

Ionone derivatives from Alternanthera sessilis.  

PubMed

The chloroform extract of the air-dried leaves of Alternanthera sessilis afforded a mixture of diastereomers of a new ionone derivative 1 whose structures were elucidated by extensive 1D and 2D NMR spectroscopy and mass spectrometry. Oxidative cleavage of 1 to aldehyde 3 with manganese dioxide confirmed diastereoisomerism arose from a racemic side chain chiral centre. Antimicrobial tests on the mixture of diastereomers and the derivative indicated that they have low activities against Pseudomonas aeruginosa and Trichophyton mentagrophytes. PMID:12067155

Ragasa, Consolacion Y; Tremor, Noemi; Rideout, John A

2002-06-01

225

Colorimetric fluorescent cyanide chemodosimeter based on triphenylimidazole derivative.  

PubMed

In this paper, we demonstrated a highly selective colorimetric chemodosimeter for cyanide anion detection. This chemodosimeter having a triphenylimidazole group as a fluorescent signal unit and a dicyano-vinyl group as a reaction unit was synthesized by the Knoevenagel condensation of 4-(4,5-diphenyl-1H-imidazol-2-yl)benzaldehyde with malononitrile in a reasonable yield. The probe exhibited an intramolecular charge transfer (ICT) absorption band at 420 nm and emission band at 620 nm, respectively. Upon the addition of cyanide anion, the probe displayed a blue-shifted spectrum and loss in color due to the disruption of conjugation. With the aid of the fluorescence spectrometer, the chemodosimeter exhibited a detection limit of 0.11 ?M (S/N=3). Interferences from other common anions associated with cyanide anion analysis were effectively inhibited. PMID:24463246

Zheng, Wei; He, Xiangzhu; Chen, Hongbiao; Gao, Yong; Li, Huaming

2014-04-24

226

2-Benzoyl-4-chloro­aniline thio­semi­carbazone  

PubMed Central

In the title compound, C14H13ClN4S, obtained from a reaction of 2-benzoyl-4-chloro­aniline with thio­semicarbazide in ethanol, the dihedral angle between the aromatic rings is 81.31?(13)°. In the crystal, the mol­ecules are linked by three N—H?S hydrogen bonds, forming centrosymmetric rings with set-graph motif R 2 2(8) and R 2 2(18), and resulting in the formation of a two-dimensional network lying parallel to (010). PMID:24940260

Bandeira, Katlen C. T.; Bresolin, Leandro; Lehmann, Ueslei Z.; Zambiazi, Priscilla J.; de Oliveira, Adriano Bof

2014-01-01

227

Antifungal and Antioxidant Activities of Pyrrolidone Thiosemicarbazone Complexes  

PubMed Central

Metal complexes of (Z)-2-(pyrrolidin-2-ylidene)hydrazinecarbothioamide (L) with Cu(II), Co(II), and Ni(II) chlorides were tested against selected types of fungi and were found to have significant antifungal activities. The free-radical-scavenging ability of the metal complexes was determined by their interaction with the stable free radical 2,2??-diphenyl-1-picrylhydrazyl, and all the compounds showed encouraging antioxidant activities. DFT calculations of the Cu complex were performed using molecular structures with optimized geometries. Molecular orbital calculations provide a detailed description of the orbitals, including spatial characteristics, nodal patterns, and the contributions of individual atoms. PMID:22400016

Al-Amiery, Ahmed A.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar

2012-01-01

228

Antifungal and antioxidant activities of pyrrolidone thiosemicarbazone complexes.  

PubMed

Metal complexes of (Z)-2-(pyrrolidin-2-ylidene)hydrazinecarbothioamide (L) with Cu(II), Co(II), and Ni(II) chlorides were tested against selected types of fungi and were found to have significant antifungal activities. The free-radical-scavenging ability of the metal complexes was determined by their interaction with the stable free radical 2,2''-diphenyl-1-picrylhydrazyl, and all the compounds showed encouraging antioxidant activities. DFT calculations of the Cu complex were performed using molecular structures with optimized geometries. Molecular orbital calculations provide a detailed description of the orbitals, including spatial characteristics, nodal patterns, and the contributions of individual atoms. PMID:22400016

Al-Amiery, Ahmed A; Kadhum, Abdul Amir H; Mohamad, Abu Bakar

2012-01-01

229

Derivative-Free Optimization Proximal Point Methods Derivative-Free Proximal Point Conclusion Derivative-Free Optimization via Proximal  

E-print Network

Derivative-Free Optimization Proximal Point Methods Derivative-Free Proximal Point Conclusion Derivative-Free Optimization via Proximal Point Methods Yves Lucet & Warren Hare July 24, 2013 1 / 26 #12;Derivative-Free Optimization Proximal Point Methods Derivative-Free Proximal Point Conclusion Outline 1

230

Drugs derived from phage display  

PubMed Central

Phage display, one of today’s fundamental drug discovery technologies, allows identification of a broad range of biological drugs, including peptides, antibodies and other proteins, with the ability to tailor critical characteristics such as potency, specificity and cross-species binding. Further, unlike in vivo technologies, generating phage display-derived antibodies is not restricted by immunological tolerance. Although more than 20 phage display-derived antibody and peptides are currently in late-stage clinical trials or approved, there is little literature addressing the specific challenges and successes in the clinical development of phage-derived drugs. This review uses case studies, from candidate identification through clinical development, to illustrate the utility of phage display as a drug discovery tool, and offers a perspective for future developments of phage display technology. PMID:24262785

Nixon, Andrew E; Sexton, Daniel J; Ladner, Robert C

2014-01-01

231

Pregnane derivatives from Potentilla evestita.  

PubMed

A new pregnane derivative, 2,6beta,7beta-trihydroxy-4-methyl-19-norpregna-1,3,5(10)-trien-17-one, has been isolated from the ethyl acetate soluble fraction of Potentilla evestita along with a pregnane derivative, 11alpha,17alpha,21-trihydroxypregna-4,16(22)-diene-3,20-dione, that is reported for the first time as a natural product. Their structures were elucidated with the aid of 1H and 13C NMR spectra and by COSY, HMQC, HMBC and NOESY experiments. PMID:21922903

Khan, Rehan; Siddiq, Farah; Fatima, Itrat; Yasmeen, Shazia; Karim, Aman; Malik, Abdul; Afza, Nighat; Hameed, Saira

2011-08-01

232

Canonical derivation of effective potentials  

E-print Network

A canonical formulation of effective equations describes quantum corrections by the back-reaction of moments on the dynamics of expectation values of a state. As a first step toward an extension to quantum-field theory, these methods are applied here to the derivation of effective potentials around a homogeneous vacuum expectation value of scalar fields. A comparison with the standard Coleman-Weinberg potential shows that the new methods correctly include all relevant quantum corrections. At the same time, the effective potential is shown to be correct also for non-Fock and mixed states. Several explicit results are derived in models of interacting scalars and fermions.

Martin Bojowald; Suddhasattwa Brahma

2014-11-13

233

Canonical derivation of effective potentials  

E-print Network

A canonical formulation of effective equations describes quantum corrections by the back-reaction of moments on the dynamics of expectation values of a state. As a first step toward an extension to quantum-field theory, these methods are applied here to the derivation of effective potentials around a homogeneous vacuum expectation value of scalar fields. A comparison with the standard Coleman-Weinberg potential shows that the new methods correctly include all relevant quantum corrections. At the same time, the effective potential is shown to be correct also for non-Fock and mixed states. Several explicit results are derived in models of interacting scalars and fermions.

Bojowald, Martin

2014-01-01

234

Fractional Derivatives in Dengue Epidemics  

NASA Astrophysics Data System (ADS)

We introduce the use of fractional calculus, i.e., the use of integrals and derivatives of non-integer (arbitrary) order, in epidemiology. The proposed approach is illustrated with an outbreak of dengue disease, which is motivated by the first dengue epidemic ever recorded in the Cape Verde islands off the coast of west Africa, in 2009. Numerical simulations show that in some cases the fractional models fit better the reality when compared with the standard differential models. The classical results are obtained as particular cases by considering the order of the derivatives to take an integer value.

Pooseh, Shakoor; Rodrigues, Helena Sofia; Torres, Delfim F. M.

2011-09-01

235

40 CFR 721.10039 - Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative...  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative, ammonium salt (generic). 721...721.10039 Diethoxybenzenamine derivative, diazotized, coupled with...

2010-07-01

236

On derivations of low dimensional associative dialgebras  

NASA Astrophysics Data System (ADS)

This study introduces a new algorithm for finding derivation of associative dialgebras. The algorithm applied to compute the derivations of low dimensional associative dialgebras. Some simple properties of derivation in terms of left multiplication operators also are provided.

Abubakar, Mohamed; Rakhimov, I. S.; Rikhsiboev, I. M.

2014-06-01

237

28 CFR 17.26 - Derivative classification.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Derivative classification. 17.26 Section...Classified Information § 17.26 Derivative classification. (a) Persons...classification guides. (b) Persons who apply derivative classification markings shall...

2010-07-01

238

40 CFR 721.1820 - Bisphenol derivative.  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Bisphenol derivative. 721.1820 Section 721.1820...Substances § 721.1820 Bisphenol derivative. (a) Chemical substance and significant...substance identified generically as bisphenol derivative (PMN No. P-92-509) is...

2010-07-01

239

40 CFR 721.5913 - Phenothiazine derivative.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Phenothiazine derivative. 721.5913 Section 721.5913...Substances § 721.5913 Phenothiazine derivative. (a) Chemical substance and significant...identified generically as a phenothiazine derivative (PMN P-96-813) is subject...

2010-07-01

240

32 CFR 2001.22 - Derivative classification.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Derivative classification. 2001.22 Section...Identification and Markings § 2001.22 Derivative classification. (a) General... (b) Identity of persons who apply derivative classification markings....

2010-07-01

241

40 CFR 721.9658 - Thiadiazole derivative.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Thiadiazole derivative. 721.9658 Section 721.9658...Substances § 721.9658 Thiadiazole derivative. (a) Chemical substance and significant...substance identified as a thiadiazole derivative (PMN P-94-1631) is subject...

2010-07-01

242

46 CFR 503.55 - Derivative classification.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Derivative classification. 503.55 Section...Information Security Program § 503.55 Derivative classification. (a) In...apply to the source information, is derivative classification. (1)...

2010-10-01

243

Quantum White Noise Derivatives and Implementation Problem  

E-print Network

. . Quantum White Noise Derivatives and Implementation Problem On the occasion of thier 60th, 2009 Nobuaki Obata (GSIS, Tohoku University) Quantum White Noise Derivatives and Implementation Problem (GSIS, Tohoku University) Quantum White Noise Derivatives and Implementation Problem Fukuoka, November

Obata, Nobuaki

244

Informational derivation of quantum theory  

SciTech Connect

We derive quantum theory from purely informational principles. Five elementary axioms - causality, perfect distinguishability, ideal compression, local distinguishability, and pure conditioning - define a broad class of theories of information processing that can be regarded as standard. One postulate - purification - singles out quantum theory within this class.

Chiribella, Giulio; D'Ariano, Giacomo Mauro; Perinotti, Paolo [Perimeter Institute for Theoretical Physics, 31 Caroline Street North, Ontario, N2L 2Y5 (Canada); QUIT Group, Dipartimento di Fisica ''A. Volta'' and INFN Sezione di Pavia, via Bassi 6, I-27100 Pavia (Italy)

2011-07-15

245

Deriving Laws from Ordering Relations  

Microsoft Academic Search

The effect of Richard T. Cox’s contribution to probability theory was to generalize Boolean implication among logical statements to degrees of implication, which are manipulated using rules derived from consistency with Boolean algebra. These rules are known as the sum rule, the product rule and Bayes’ Theorem, and the measure resulting from this generalization is probability. In this paper, I

Kevin H. Knuth; Moffett Field CA

2004-01-01

246

Quaternion Derivatives: The GHR Calculus  

E-print Network

Quaternion derivatives in the mathematical literature are typically defined only for analytic (regular) functions. However, in engineering problems, functions of interest are often real-valued and thus not analytic, such as the standard cost function. The HR calculus is a convenient way to calculate formal derivatives of both analytic and non-analytic functions of quaternion variables, however, both the HR and other functional calculus in quaternion analysis have encountered an essential technical obstacle, that is, the traditional product rule is invalid due to the non- commutativity of the quaternion algebra. To address this issue, a generalized form of the HR derivative is proposed based on a general orthogonal system. The so introduced generalization, called the generalized HR (GHR) calculus, encompasses not just the left- and right-hand versions of quaternion derivative, but also enables solutions to some long standing problems, such as the novel product rule, the chain rule, the mean-valued theorem and Taylor's theorem. At the core of the proposed approach is the quaternion rotation, which can naturally be applied to other functional calculi in non-commutative settings. Examples on using the GHR calculus in adaptive signal processing support the analysis.

Dongpo Xu; Cyrus Jahanchahi; Clive C. Took; Danilo P. Mandic

2014-09-25

247

Influence of lignocellulose-derived aromatic compounds on oxygen-limited growth and ethanolic fermentation by Saccharomyces cerevisiae  

Microsoft Academic Search

Phenolic compounds released and generated during hydrolysis inhibit fermentation of lignocellulose hydrolysates to ethanol\\u000a by Saccharomyces cerevisiae. A wide variety of aromatic compounds form from lignin, which is partially degraded during acid hydrolysis of the lignocellulosic\\u000a raw material. Aromatic compounds may also form as a result of sugar degradation and dare present in wood as extractives. The\\u000a influence of hydroxy-methoxy-benzaldehydes,

Simona Larsson; Alexis Quintana-Sáinz; Andres Reimann; Nils-Olof Nilvebrant; Leif J. Jönsson

2000-01-01

248

On Derivations Of Genetic Algebras  

NASA Astrophysics Data System (ADS)

A genetic algebra is a (possibly non-associative) algebra used to model inheritance in genetics. In application of genetics this algebra often has a basis corresponding to genetically different gametes, and the structure constant of the algebra encode the probabilities of producing offspring of various types. In this paper, we find the connection between the genetic algebras and evolution algebras. Moreover, we prove the existence of nontrivial derivations of genetic algebras in dimension two.

Mukhamedov, Farrukh; Qaralleh, Izzat

2014-11-01

249

Electrofugality index for benzhydryl derivatives  

NASA Astrophysics Data System (ADS)

We propose and test an empirical electrofugality index to rank the leaving group ability of a series of 21 benzhydryl derivatives. The empirical model defines the electrofugality as the negative of the global electrophilicity of the carbocation intermediate in the hydrolysis reaction. The results are in good agreement with the experimental electrofugality scale proposed for the title compounds by Mayr and coworkers [B. Denegri, A. Streiter, S. Júric, A.R. Ofial, O. Kronja, H. Mayr, Chem. Eur. J. 12 (2006) 1648].

Campodónico, Paola R.; Pérez, Claudio; Aliaga, Margarita; Gazitúa, Marcela; Contreras, Renato

2007-10-01

250

Derivation of Hamiltonians for accelerators  

SciTech Connect

In this report various forms of the Hamiltonian for particle motion in an accelerator will be derived. Except where noted, the treatment will apply generally to linear and circular accelerators, storage rings, and beamlines. The generic term accelerator will be used to refer to any of these devices. The author will use the usual accelerator coordinate system, which will be introduced first, along with a list of handy formulas. He then starts from the general Hamiltonian for a particle in an electromagnetic field, using the accelerator coordinate system, with time t as independent variable. He switches to a form more convenient for most purposes using the distance s along the reference orbit as independent variable. In section 2, formulas will be derived for the vector potentials that describe the various lattice components. In sections 3, 4, and 5, special forms of the Hamiltonian will be derived for transverse horizontal and vertical motion, for longitudinal motion, and for synchrobetatron coupling of horizontal and longitudinal motions. Hamiltonians will be expanded to fourth order in the variables.

Symon, K.R.

1997-09-12

251

An assessment of derived flood frequency distributions  

E-print Network

Flood Frequency Curve - Turtle Creek. . . FIG. 9. Statistical Flood Frequency Curve - Halls Bayou . . . . . . 51 . . . 51 FIG. 10. Derived Flood Frequency Curves ? South Rocky Creek. . . . . . 53 FIG. 11. Derived Flood Frequency Curves - Briar Creek... . . FIG. 12, Derived Flood Frequency Curves - Turtle Creek. . . FIG. 13. Derived Flood Frequency Curves - Halls Bayou. . . . . . . . . . . . . . FIG. 14. Simulation Flood Frequency Curve ? South Rocky Creek. . . . . . 54 . . . 56 FIG. 15. Simulation...

Raines, Timothy Howard

1991-01-01

252

Binder enhanced refuse derived fuel  

DOEpatents

A refuse derived fuel (RDF) pellet having about 11% or more particulate calcium hydroxide which is utilized in a combustionable mixture. The pellets are used in a particulate fuel bring a mixture of 10% or more, on a heat equivalent basis, of the RDF pellet which contains calcium hydroxide as a binder, with 50% or more, on a heat equivalent basis, of a sulphur containing coal. Combustion of the mixture is effective to produce an effluent gas from the combustion zone having a reduced SO.sub.2 and polycyclic aromatic hydrocarbon content of effluent gas from similar combustion materials not containing the calcium hydroxide.

Daugherty, Kenneth E. (Lewisville, TX); Venables, Barney J. (Denton, TX); Ohlsson, Oscar O. (Naperville, IL)

1996-01-01

253

Deriving Ontologies from XML Schema  

E-print Network

In this paper, we present a method and a tool for deriving a skeleton of an ontology from XML schema files. We first recall what an is ontology and its relationships with XML schemas. Next, we focus on ontology building methodology and associated tool requirements. Then, we introduce Janus, a tool for building an ontology from various XML schemas in a given domain. We summarize the main features of Janus and illustrate its functionalities through a simple example. Finally, we compare our approach to other existing ontology building tools.

Bedini, Ivan; Nguyen, Benjamin

2010-01-01

254

Generalized derivatives and generalized convexities  

SciTech Connect

We give a survey of the contributions of the speaker and of his co-authors in the use of nonsmooth analysis for the study of generalized convexities such as quasiconvexity, pseudoconvexity, invexity. One line of though corresponds to the use of generalized directional derivatives, as in S. Komlosi. Another track consists in using a subdifferential. This could be done in an axiomatic way, but we use essentially three classical instances; the Clarke subdifferential, the contingent subdifferential and the Frechet subdifferential. For algorithmic purposes, variants of Plastra`s subdifferential can be use.

Penot, J.P.; Quang, P.H.; Sach, P.H.

1994-12-31

255

Diagrammatic Derivation of Lovelock Densities  

E-print Network

We discuss a method of calculating the various scalar densities encountered in Lovelock theory which relies on diagrammatic, instead of algebraic manipulations. Taking advantage of the known symmetric and antisymmetric properties of the Riemann tensor which appears in the Lovelock densities, we map every quadratic or higher contraction into a corresponding permutation diagram. The derivation of the explicit form of each density is then reduced to identifying the distinct diagrams, from which we can also read off the overall combinatoric factors. The method is applied to the first Lovelock densities, of order two (Gauss-Bonnet term) and three.

C. Bogdanos

2009-04-19

256

Diagrammatic derivation of Lovelock densities  

SciTech Connect

We discuss a method of calculating the various scalar densities encountered in Lovelock theory, which relies on diagrammatic, instead of algebraic manipulations. Taking advantage of the known symmetric and antisymmetric properties of the Riemann tensor that appears in the Lovelock densities, we map every quadratic or higher contraction into a corresponding permutation diagram. The derivation of the explicit form of each density is then reduced to identifying the distinct diagrams, from which we can also read off the overall combinatoric factors. The method is applied to the first Lovelock densities, of order two (Gauss-Bonnet term) and three.

Bogdanos, C. [Laboratoire de Physique Theorique, Universite de Paris-Sud 11, Batiment 210, 91405 Orsay CEDEX (France)

2009-05-15

257

Diagrammatic derivation of Lovelock densities  

NASA Astrophysics Data System (ADS)

We discuss a method of calculating the various scalar densities encountered in Lovelock theory, which relies on diagrammatic, instead of algebraic manipulations. Taking advantage of the known symmetric and antisymmetric properties of the Riemann tensor that appears in the Lovelock densities, we map every quadratic or higher contraction into a corresponding permutation diagram. The derivation of the explicit form of each density is then reduced to identifying the distinct diagrams, from which we can also read off the overall combinatoric factors. The method is applied to the first Lovelock densities, of order two (Gauss-Bonnet term) and three.

Bogdanos, C.

2009-05-01

258

Fourth order spatial derivative gravity  

SciTech Connect

In this work, we study a modified theory of gravity that contains up to fourth order spatial derivatives as a model for the Horava-Lifshitz gravity. The propagator is evaluated and, as a result, one extra pole is obtained, corresponding to a spin-2 nonrelativistic massless particle, an extra term which jeopardizes renormalizability, besides the unexpected general relativity unmodified propagator. Then unitarity is proved at the tree level, where the general relativity pole has been shown to have no dynamics, remaining only the 2 degrees of freedom of the new pole. Next, the nonrelativistic effective potential is determined from a scattering process of two identical massive gravitationally interacting bosons. In this limit, Newton's potential is obtained, together with a Darwin-like term that comes from the extra nonpole term in the propagator. Regarding renormalizability, this extra term may be harmful by power counting, but it can be eliminated by adjusting the free parameters of the model. This adjustment is in accord with the detailed balance condition suggested in the literature and shows that the way in which extra spatial derivative terms are added is of fundamental importance.

Bemfica, F. S.; Gomes, M. [Instituto de Fisica, Universidade de Sao Paulo Caixa Postal 66318, 05315-970, Sao Paulo, SP (Brazil)

2011-10-15

259

Paleovirology and virally derived immunity.  

PubMed

Paleovirology, the study of viruses on evolutionary timescales, can exploit information from endogenous viral elements (EVEs), which are the result of heritable horizontal gene transfer (HGT) from viruses to hosts. The availability of genomic data has increased opportunities to study EVEs, and bioinformatics techniques have been crucial in cataloguing EVE diversity and taxonomic coverage. Recent advances show that some EVEs have been co-opted as cellular genes, often as inhibitors of viral infection. These genes are an intriguing strategy in virus-host evolutionary battles in that genetic material is transferred from virus to host, and then used by the host against the virus. In this review, we consider the genes and processes involved in EVE-derived immunity (EDI), assess factors leading to its emergence, and outline how future work will benefit from incorporating evolutionary approaches. PMID:22901901

Aswad, Amr; Katzourakis, Aris

2012-11-01

260

Optical nonlinearities of perylene derivatives  

NASA Astrophysics Data System (ADS)

Nonlinear optical properties of perylene derivatives were studied by femtosecond Z-scan technique. 3,4,9,10-Perylenetetracarboxylic dianhydride (PTCDA), 3,4,9,10-perylenetetracarboxylic diimide (PTCDI), and perylene-66 (dibenzthiophenoperylene-N,N'-dicyclohexylimide), were studied. Tetrahydrofuran was used as a solvent for perylene- 66. The solubility of PTCDA and PTCDI is very poor. Their colloidal solution was prepared by the irradiation of the third harmonics of a pulsed YAG laser to opaque suspension of PTCDA and PTCDI. Transparent colloidal solution was obtained within 50 minutes of UV irradiation. Colloidal solution of quinacridone was also studied. Two-photon absorption cross sections of these dyes were measured by open aperture Z-scan method using a femtosecond laser. The dependence of two-photon cross section on laser wavelength was measured in the wavelength range of 780-820 nm.

Sasaki, Yoshihiko; Takamo, Hiroyuki; Kasatani, Kazuo

2008-01-01

261

Deriving Laws from Ordering Relations  

NASA Technical Reports Server (NTRS)

It took much effort in the early days of non-Euclidean geometry to break away from the mindset that all spaces are flat and that two distinct parallel lines do not cross. Up to that point, all that was known was Euclidean geometry, and it was difficult to imagine anything else. We have suffered a similar handicap brought on by the enormous relevance of Boolean algebra to the problems of our age-logic and set theory. Previously, I demonstrated that the algebra of questions is not Boolean, but rather is described by the free distributive algebra. To get to this stage took much effort, as many obstacles-most self-placed-had to be overcome. As Boolean algebras were all I had ever known, it was almost impossible for me to imagine working with an algebra where elements do not have complements. With this realization, it became very clear that the sum and product rules of probability theory at the most basic level had absolutely nothing to do with the Boolean algebra of logical statements. Instead, a measure of degree of inclusion can be invented for many different partially ordered sets, and the sum and product rules fall out of the associativity and distributivity of the algebra. To reinforce this very important idea, this paper will go over how these constructions are made, while focusing on the underlying assumptions. I will derive the sum and product rules for a distributive lattice in general and demonstrate how this leads to probability theory on the Boolean lattice and is related to the calculus of quantum mechanical amplitudes on the partially ordered set of experimental setups. I will also discuss the rules that can be derived from modular lattices and their relevance to the cross-ratio of projective geometry.

Knuth, Kevin H.

2003-01-01

262

Deriving Ephemeral Authentication Using Channel Axioms  

E-print Network

Deriving Ephemeral Authentication Using Channel Axioms Dusko Pavlovic1 and Catherine Meadows2 1 of Mathematics/ISG. #12;Deriving Ephemeral Authentication Using Channel Axioms 239 of the information sent along

Sheldon, Nathan D.

263

5 CFR 2500.5 - Derivative classification.  

Code of Federal Regulations, 2010 CFR

...Personnel 3 2010-01-01 2010-01-01 false Derivative classification. 2500.5 Section 2500.5 Administrative...PRESIDENT INFORMATION SECURITY REGULATION § 2500.5 Derivative classification. The Office of Administration serves...

2010-01-01

264

17 CFR 200.506 - Derivative classification.  

Code of Federal Regulations, 2010 CFR

...Exchanges 2 2010-04-01 2010-04-01 false Derivative classification. 200.506 Section 200.506 Commodity...National Security Information and Material § 200.506 Derivative classification. Any document that includes...

2010-04-01

265

12 CFR 563.172 - Financial derivatives.  

Code of Federal Regulations, 2012 CFR

... SAVINGS ASSOCIATIONS-OPERATIONS Financial Management Policies § 563.172 Financial derivatives...responsible for daily oversight and management of financial derivatives activities. Management must implement the policies and...

2012-01-01

266

12 CFR 563.172 - Financial derivatives.  

Code of Federal Regulations, 2011 CFR

... SAVINGS ASSOCIATIONS-OPERATIONS Financial Management Policies § 563.172 Financial derivatives...responsible for daily oversight and management of financial derivatives activities. Management must implement the policies and...

2011-01-01

267

12 CFR 563.172 - Financial derivatives.  

Code of Federal Regulations, 2014 CFR

... SAVINGS ASSOCIATIONS-OPERATIONS Financial Management Policies § 563.172 Financial derivatives...responsible for daily oversight and management of financial derivatives activities. Management must implement the policies and...

2014-01-01

268

12 CFR 163.172 - Financial derivatives.  

Code of Federal Regulations, 2013 CFR

... SAVINGS ASSOCIATIONS-OPERATIONS Financial Management Policies § 163.172 Financial derivatives...responsible for daily oversight and management of financial derivatives activities. Management must implement the policies and...

2013-01-01

269

12 CFR 563.172 - Financial derivatives.  

Code of Federal Regulations, 2013 CFR

... SAVINGS ASSOCIATIONS-OPERATIONS Financial Management Policies § 563.172 Financial derivatives...responsible for daily oversight and management of financial derivatives activities. Management must implement the policies and...

2013-01-01

270

12 CFR 163.172 - Financial derivatives.  

Code of Federal Regulations, 2014 CFR

... SAVINGS ASSOCIATIONS-OPERATIONS Financial Management Policies § 163.172 Financial derivatives...responsible for daily oversight and management of financial derivatives activities. Management must implement the policies and...

2014-01-01

271

A study on real estate derivatives  

E-print Network

All major asset classes including stocks and bonds have a well developed derivative market. Derivatives enable counterparties to reflect a view on a particular market, without having to trade the underlying asset. This ...

Lim, Jong Yoon, S.M. Massachusetts Institute of Technology

2006-01-01

272

40 CFR 721.10039 - Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative...  

Code of Federal Regulations, 2011 CFR

...aminonaphthalenesulfonic acid derivative, ammonium salt (generic). 721.10039 Section 721...aminonaphthalenesulfonic acid derivative, ammonium salt (generic). (a) Chemical substance...aminonaphthalenesulfonic acid derivative, ammonium salt (PMN P-02-514) is subject to...

2011-07-01

273

40 CFR 721.10039 - Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative...  

Code of Federal Regulations, 2014 CFR

...aminonaphthalenesulfonic acid derivative, ammonium salt (generic). 721.10039 Section 721...aminonaphthalenesulfonic acid derivative, ammonium salt (generic). (a) Chemical substance...aminonaphthalenesulfonic acid derivative, ammonium salt (PMN P-02-514) is subject to...

2014-07-01

274

40 CFR 721.10039 - Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative...  

Code of Federal Regulations, 2013 CFR

...aminonaphthalenesulfonic acid derivative, ammonium salt (generic). 721.10039 Section 721...aminonaphthalenesulfonic acid derivative, ammonium salt (generic). (a) Chemical substance...aminonaphthalenesulfonic acid derivative, ammonium salt (PMN P-02-514) is subject to...

2013-07-01

275

Stability derivatives of cones at supersonic speeds  

NASA Technical Reports Server (NTRS)

The aerodynamic stability derivatives due to pitching velocity and vertical acceleration are derived for circular cones traveling at supersonic speeds. Both first-order and a combination of first and second order potential solutions are obtained, and in calculations for the forces, no approximations are made to the tangency condition or the isentropic pressure relation. In addition, expressions for the forces, moments, and stability derivatives of arbitrary bodies of revolution are derived from Newtonian impact theory.

Tobak, Murry; Wehrend, William R

1956-01-01

276

Derived data for decision support systems  

Microsoft Academic Search

In decision-making situations requiring “what-if” analysis, in statistical databases, and in distributed databases, it is desirable to explicitly store derived data without losing consistency with the original data. We introduce independently-updated views (IUVs) for storage and use of derived data for decision-support systems. IUVs support multiple versions, provide derivation transparency, maintain data consistency, and afford control over time of derivation.

Richard G. Ramirez; Uday R. Kulkarni; Kathleen A. Moser

1996-01-01

277

Improved Second Derivative Test for Relative Extrema  

ERIC Educational Resources Information Center

In this note, a modified Second Derivative Test is introduced for the relative extrema of a single variable function. This improved test overcomes the difficulty of the second derivative vanishing at the critical point, while in contrast the traditional test fails for this case. A proof for this improved Second Derivative Test is presented,…

Wu, Yan

2007-01-01

278

Structural design utilizing updated, approximate sensitivity derivatives  

NASA Technical Reports Server (NTRS)

A method to improve the computational efficiency of structural optimization algorithms is investigated. In this method, the calculations of 'exact' sensitivity derivatives of constraint functions are performed only at selected iterations during the optimization process. The sensitivity derivatives utilized within other iterations are approximate derivatives which are calculated using an inexpensive derivative update formula. Optimization results are presented for an analytic optimization problem (i.e., one having simple polynomial expressions for the objective and constraint functions) and for two structural optimization problems. The structural optimization results indicate that up to a factor of three improvement in computation time is possible when using the updated sensitivity derivatives.

Scotti, Stephen J.

1993-01-01

279

Unconventional fuel: Tire derived fuel  

SciTech Connect

Material recovery of scrap tires for their fuel value has moved from a pioneering concept in the early 1980`s to a proven and continuous use in the United States` pulp and paper, utility, industrial, and cement industry. Pulp and paper`s use of tire derived fuel (TDF) is currently consuming tires at the rate of 35 million passenger tire equivalents (PTEs) per year. Twenty mills are known to be burning TDF on a continuous basis. The utility industry is currently consuming tires at the rate of 48 million PTEs per year. Thirteen utilities are known to be burning TDF on a continuous basis. The cement industry is currently consuming tires at the rate of 28 million PTEs per year. Twenty two cement plants are known to be burning TDF on a continuous basis. Other industrial boilers are currently consuming tires at the rate of 6.5 million PTEs per year. Four industrial boilers are known to be burning TDF on a continuous basis. In total, 59 facilities are currently burning over 117 million PTEs per year. Although 93% of these facilities were not engineered to burn TDF, it has become clear that TDF has found acceptance as a supplemental fuel when blending with conventional fuels in existing combustion devices designed for normal operating conditions. The issues of TDF as a supplemental fuel and its proper specifications are critical to the successful development of this fuel alternative. This paper will focus primarily on TDF`s use in a boiler type unit.

Hope, M.W. [Waste Recovery, Inc., Portland, OR (United States)

1995-09-01

280

Clinical status of benzoporphyrin derivative  

NASA Astrophysics Data System (ADS)

Benzoporphyrin derivative monoacid ring A (BPD) is currently in Phase II clinical trials for the treatment of cutaneous malignancies (basal cell carcinoma and cutaneous metastases) and psoriasis. Results to date suggest that this photosensitizer has potential in both of these areas. Recently, a clinical trial with BPD was initiated for the treatment of age related macular degeneration, a neovascular condition in the eye which leads to blindness. BPD is a lipophilic photosensitizer which is rapidly taken up by activated cells and the vascular endothelium of neovasculature. The PDT effects seen with BPD appear to be a combination of vascular occlusion and direct killing of target cells. Since many diseases involve either activated cells and/or neovasculature, PDT with photosensitizer with characteristics like those of BPD, has applications far wider than oncology. A new area of interest involving photosensitizers is that of immune modulation. A number of photosensitizers have been shown to effect immune modulation in animal models of immune dysfunction including autoimmunity (rheumatoid arthritis, lupus), cutaneous hypersensitivity and allografts. BPD and PHOTOFRINR have both been shown to be effective in ameliorating arthritic symptoms in a number of animal models. The mechanisms by which immune modulation is affected in these studies still remains to be resolved.

Levy, Julia G.; Chan, Agnes H.; Strong, H. Andrew

1996-01-01

281

Chromatography of urinary indole derivatives.  

PubMed

Latest strategies are discussed for the routine chromatographic analysis of clinically important indole derivatives in urine. Analysis of 5-hydroxyindoleacetic acid and, perhaps more importantly, serotonin and 5-hydroxytryptophan remains attractive in the screening for carcinoid tumours and their differentiation. Analyses of two precursors of the skin pigment eumelanin seem to be promising in the monitoring of treatment of malignant melanoma and screening for pigmentation disorders and gallstone formation. Studies on the clinical relevance of the determination of tetrahydro-beta-carbolines and melatonin-related indoles await routine application of chromatographic methods designed to take into consideration the relative instability of these compounds. Application of GC-MS, although confined to larger and/or governmental laboratories remains attractive as a way of improving the specificity of analyses and in establishing reference methods. As for HPLC, the recent development of chromatographic and detection methods for the concurrent determination of different clinically important and metabolically related compounds from the same sample, preferably by direct injection techniques, seems to be fruitful and should be continued. PMID:3062030

van Haard, P M

1988-07-29

282

Representations of partial derivatives in thermodynamics  

NSDL National Science Digital Library

One of the mathematical objects that students become familiar with in thermodynamics, often for the first time, is the partial derivative of a multivariable function. The symbolic representation of a partial derivative and related quantities present difficulties for students in both mathematical and physical contexts, most notably what it means to keep one or more variables fixed while taking the derivative with respect to a different variable. Material properties are themselves written as partial derivatives of various state functions (e.g., compressibility is a partial derivative of volume with respect to pressure). Research in courses at the University of Maine and Oregon State University yields findings related to the many ways that partial derivatives can be represented and interpreted in thermodynamics. Research has informed curricular development that elicits many of the difficulties using different representations (e.g., geometric) and different contexts (e.g., connecting partial derivatives to specific experiments).

Thompson, John R.; Manogue, Corinne A.; Roundy, David J.; Mountcastle, Donald B.

2012-05-15

283

Satellite-Derived Management Zones  

NASA Technical Reports Server (NTRS)

The term "satellite-derived management zones" (SAMZ) denotes agricultural management zones that are subdivisions of large fields and that are derived from images of the fields acquired by instruments aboard Earth-orbiting satellites during approximately the past 15 years. "SAMZ" also denotes the methodology and the software that implements the methodology for creating such zones. The SAMZ approach is one of several products of continuing efforts to realize a concept of precision agriculture, which involves optimal variations in seeding, in application of chemicals, and in irrigation, plus decisions to farm or not to farm certain portions of fields, all in an effort to maximize profitability in view of spatial and temporal variations in the growth and health of crops, and in the chemical and physical conditions of soils. As used here, "management zone" signifies, more precisely, a subdivision of a field within which the crop-production behavior is regarded as homogeneous. From the perspective of precision agriculture, management zones are the smallest subdivisions between which the seeding, application of chemicals, and other management parameters are to be varied. In the SAMZ approach, the main sources of data are the archives of satellite imagery that have been collected over the years for diverse purposes. One of the main advantages afforded by the SAMZ approach is that the data in these archives can be reused for purposes of precision agriculture at low cost. De facto, these archives contain information on all sources of variability within a field, including weather, crop types, crop management, soil types, and water drainage patterns. The SAMZ methodology involves the establishment of a Web-based interface based on an algorithm that generates management zones automatically and quickly from archival satellite image data in response to requests from farmers. A farmer can make a request by either uploading data describing a field boundary to the Web site or else drawing the boundary on a reference image. Hence, a farmer can start to engage in precision farming shortly after gaining access to the Web site, without the need for incurring the high costs of conventional precision-agriculture data-collection practices that include collecting soil samples, mapping electrical conductivity of soil, and compiling multiyear crop-yield data. Given the boundary of a field, a SAMZ server computes the zones within the field in a three-stage process. In the first stage, a vector-valued image of the field is constructed by assembling, from the archives, the equivalent of a stack of the available images of the field (see figure). In the second stage, the vector-valued image is analyzed by use of a wavelet transform that detects spatial variations considered significant for precision farming while suppressing small-scale heterogeneities that are regarded as insignificant. In the third stage, a segmentation algorithm assembles the zones from smaller regions that have been identified in the wavelet analysis.

Lepoutre, Damien; Layrol, Laurent

2005-01-01

284

A newly synthesized thiazole derivative as a fluoride ion chemosensor: naked-eye, spectroscopic, electrochemical and NMR studies.  

PubMed

2,3-Indoledione 3-thiosemicarbazone (TSCI) and a novel compound 3-(2-(4-(4-phenoxyphenyl)thiazol-2-yl)hydrazono)indolin-2-one (FTHI) were synthesized with high yield and characterized by spectroscopic techniques. The complexation behaviors of TSCI and FTHI for various anionic species (F(-), Cl(-), Br(-), I(-), NO2(-), NO3(-), BzO(-), HSO4(-), ClO4(-)) in CH3CN were investigated and compared by UV-vis spectroscopy, cyclic voltammetry and (1)H NMR titration techniques. FTHI showed high degree of selectivity for fluoride over other anions. This selectivity could be easily observed by the naked eye, indicating that FTHI is potential colorimetric sensor for fluoride anion. PMID:24691372

Sar?güney, Ahmet Burak; Saf, Ahmet Özgür; Co?kun, Ahmet

2014-07-15

285

Drug Nanoparticle Formulation Using Ascorbic Acid Derivatives  

PubMed Central

Drug nanoparticle formulation using ascorbic acid derivatives and its therapeutic uses have recently been introduced. Hydrophilic ascorbic acid derivatives such as ascorbyl glycoside have been used not only as antioxidants but also as food and pharmaceutical excipients. In addition to drug solubilization, drug nanoparticle formation was observed using ascorbyl glycoside. Hydrophobic ascorbic acid derivatives such as ascorbyl mono- and di-n-alkyl fatty acid derivatives are used either as drugs or carrier components. Ascorbyl n-alkyl fatty acid derivatives have been formulated as antioxidants or anticancer drugs for nanoparticle formulations such as micelles, microemulsions, and liposomes. ASC-P vesicles called aspasomes are submicron-sized particles that can encapsulate hydrophilic drugs. Several transdermal and injectable formulations of ascorbyl n-alkyl fatty acid derivatives were used, including ascorbyl palmitate. PMID:21603195

Moribe, Kunikazu; Limwikrant, Waree; Higashi, Kenjirou; Yamamoto, Keiji

2011-01-01

286

CuI-catalyzed C-N bond formation and cleavage for the synthesis of benzimidazo[1,2-a]quinazoline derivatives.  

PubMed

A copper(I)-catalyzed domino reaction of N-(2-benzimidazolyl)-2-aminobenzamide and 2-halogenated benzaldehyde has been studied. The procedure is based on a sequential CuI-catalyzed Ullmann reaction (C-N bond formation) and two bond cleavage reactions and provides an efficient strategy for the synthesis of benzimidazo[1,2-a]quinazolines catalyzed by CuI/L-proline. PMID:24885515

Li, Chao; Zhang, Wen-Ting; Wang, Xiang-Shan

2014-06-20

287

Mantle derived economic sulfide mineralization?  

NASA Astrophysics Data System (ADS)

Sulfide ores of the unique Pt-Cu-Ni Noril'sk deposits are characterized by heavy sulfur isotopic composition (d34S = 6-18 ‰ ; Grinenko, 1985). These data are traditionally explained by the crustal contamination of the mantle melts by Devonian sedimentary rocks with anhydrites at certain depths or in a chamber of crystallization (Naldrett, 1992; Li et al., 2009). However, data on the distribution of major and trace elements and isotopic composition (their eNd, 87Sr/86Sr, d34S) in the contact zones of the intrusions with the host rocks are at variance with any significant in-situ contamination. Moreover , the mechanism of the "digestion" of this high-temperature material (Tm = 1430ºC) by the lower temperature magma (1250ºC) has never been analyzed and questioned. Our pioneering data on the sulfur radiogenic isotopes in the anhydrite are in conflict with the hypothesis that this mineral could serve as a sulfur source for the Noril'sk ores. The fact that the average composition of the intrusions is independent on the stratigraphic setting of these intrusions, which can be hosted by limestone, sandstone, and/or basalt, provides further support for the idea that no assimilation took place at the depths of the chambers in which the melts crystallized.The reason for the heavy sulfur isotopic composition of ores in the Noril'sk district is still uncertain. Last data obtained on the sulfur isotopic composition of basalts and ores from some intrusions in the Taimyr Peninsula likely provide a clue to this problem. The highest d34S values in rocks of all of the trap formations were detected in the Gudchikhinsky picrites (d34S = +8,7; Ripley et al., 2003) formed from a primitive mantle magma. They are geochemically similar to the rocks from the Dyumtaleysky Massif (d34S = 12.2; Krivolutskaya and Gongalsky, 2013) which crystallized from a primitive mantle-derived magma (with no Ta-Nb and Pb anomalies and high Gd/Yb ratio) too. This intrusion comprises economic important sulfide ores with geochemical and mineralogical characteristics similar to unique Noril'sk deposits - Talnakh, Okty'abr sky and Norilsk 1. The features of the Dyumtaleysky massif can be explained by its origin from an unusual sulfide-bearing mantle source that had sulfides through earlier crustal-mantle interaction. These data support that the mantle source of magmas in the Noril'sk district was enriched in the heavy sulfur isotope. It is the age difference that could be responsible for the unusual composition of the Noril'sk ores, because the mantle source in the Early Mesozoic was remarkably different from that in the Proterozoic one, when practically all Cu-Ni deposits worldwide were produced.

Krivolutskaya, Nadezda; Gongalskiy, Bronislav; Svirskaya, Natalia

2014-05-01

288

75 FR 63113 - Financial Resources Requirements for Derivatives Clearing Organizations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Financial Resources Requirements for Derivatives Clearing Organizations AGENCY: Commodity...financial resources requirements for derivatives clearing organizations (DCOs) for...execution requirements on standardized derivative products; (3) creating...

2010-10-14

289

Design and synthesis of new vancomycin derivatives.  

PubMed

A set of vancomycin derivatives with lipid chain attached via a glyceric acid linker was designed and synthesized. A concise synthesis towards these derivatives was developed and the IC50s of these new lipoglycopeptides were tested. Some of them showed very potent activity against both vancomycin sensitive and resistant strains. PMID:24751442

Gu, Wen; Chen, Bei; Ge, Min

2014-05-15

290

Auto-oxidative coupling of glycine derivatives.  

PubMed

The unprecedented title reaction between glycine derivatives and indoles, as well as the auto-oxidative Povarov/aromatization tandem reaction of glycine derivatives with olefins are described. The reactions were performed in the absence of redox-active catalysts and chemical oxidants under mild reaction conditions. Only simple organic solvents and air (or O2 ) were required. PMID:25288283

Huo, Congde; Yuan, Yong; Wu, Mingxia; Jia, Xiaodong; Wang, Xicun; Chen, Fengjuan; Tang, Jing

2014-12-01

291

Tilt/Integral/Derivative Compensators For Controllers  

NASA Technical Reports Server (NTRS)

Tilt/integral/derivative (TID) compensators for tunable feedback control systems offer advantages over proportional/integral/derivative compensators. Designed and adjusted more easily, and made to reject disturbances more strongly and less sensitive to variations in parameters of controlled system.

Lurie, Boris J.

1995-01-01

292

Few Fractional Order Derivatives and Their Computations  

ERIC Educational Resources Information Center

This work presents an introductory development of fractional order derivatives and their computations. Historical development of fractional calculus is discussed. This paper presents how to obtain computational results of fractional order derivatives for some elementary functions. Computational results are illustrated in tabular and graphical…

Bhatta, D. D.

2007-01-01

293

Understanding the Derivative through the Calculus Triangle  

ERIC Educational Resources Information Center

Typical treatments of the derivative do not clearly convey the idea that the derivative function represents the original function's rate of change. Revealing the relationship between a function and its rate-of-change function for static values of "x" does not facilitate productive ways of thinking about generating the rate-of-change function or…

Weber, Eric; Tallman, Michael; Byerley, Cameron; Thompson, Patrick W.

2012-01-01

294

Genetic Optimization Using Derivatives Jasjeet S. Sekhon  

E-print Network

entirely on derivatives can be unreliable and often are virtually unusable. Newton-Raphson and quasi-Newton that combines evolutionary algorithm methods with a derivative-based, quasi-Newton method to solve difficult of GENOUD to that of the Gauss-Newton algorithm in SAS's PROC MODEL. #12;Introduction We report

Sekhon, Jasjeet S.

295

On the stability of J?-derivations  

NASA Astrophysics Data System (ADS)

In this paper, we establish the stability and superstability of J?-derivations in J?-algebras for the generalized Jensen-type functional equation rf({x+y}/{r})+rf({x-y}/{r})=2f(x). Finally, we investigate the stability of J?-derivations by using the fixed point alternative.

Eshaghi Gordji, M.; Ghaemi, M. B.; Kaboli Gharetapeh, S.; Shams, S.; Ebadian, A.

2010-03-01

296

ADIFOR --- Generating Derivative Codes from Fortran Programs  

Microsoft Academic Search

. The numerical methods employed in the solution of many scientific computing problems require the computationof derivatives of a function f : Rn!Rm. Both the accuracy and the computationalrequirements of the derivative computationare usually of critical importance for the robustness and speed of the numerical solution. ADIFOR (Automatic DifferentiationIn FORtran) is a source transformation tool that accepts Fortran 77 code

1991-01-01

297

Derivation of Refraction Formulas Paul S. Heckbert  

E-print Network

Derivation of Refraction Formulas Paul S. Heckbert ABSTRACT We derive three alternative formulas for the refracted ray direction in ray tracing in order to prove their equivalence and to demonstrate the process refract when they strike an interface between two different transpar­ ent media, such as air­water, air

Treuille, Adrien

298

17 CFR 200.507 - Declassification dates on derivative documents.  

Code of Federal Regulations, 2010 CFR

... false Declassification dates on derivative documents. 200.507 Section 200...200.507 Declassification dates on derivative documents. (a) A document...need for classification. (b) A derivative document that derives its...

2010-04-01

299

ADIFOR: Fortran source translation for efficient derivatives  

SciTech Connect

The numerical methods employed in the solution of many scientific computing problems require the computation of derivatives of a function f: R{sup n} {yields} R{sup m}. Both the accuracy and the computational requirements of the derivative computation are usually of critical importance for the robustness and speed of the numerical method. ADIFOR (Automatic Differentiation In FORtran) is a source translation tool implemented using the data abstractions and program analysis capabilities of the ParaScope Parallel Programming Environment. ADIFOR accepts arbitrary Fortran-77 code defining the computation of a function and writes portable Fortran-77 code for the computation of its derivatives. In contrast to previous approaches, ADIFOR views automatic differentiation as a process of source translation that exploits computational context to reduce the cost of derivative computations. Experimental results show that ADIFOR can handle real-life codes, providing exact derivatives with a running time that is competitive with the standard divided-difference approximations of derivatives and which may perform orders of magnitude faster than divided-differences in cases. The computational scientist using ADIFOR is freed from worrying about the accurate and efficient computation of derivatives, even for complicated functions,'' and hence, is able to concentrate on the more important issues of algorithm design or system modeling. 35 refs.

Bischof, C.; Corliss, G.; Griewank, A.; Hovland, P. (Argonne National Lab., IL (United States)); Carle, A. (Rice Univ., Houston, TX (United States). Center for Research on Parallel Computation)

1992-01-01

300

Risk management, derivatives and shariah compliance  

NASA Astrophysics Data System (ADS)

Despite the impressive growth of Islamic Banking and Finance (IBF), a number of weaknesses remain. The most important of this is perhaps the lack of shariah compliant risk management tools. While the risk sharing philosophy of Islamic Finance requires the acceptance of risk to justify returns, the shariah also requires adherents to avoid unnecessary risk-maysir. The requirement to avoid maysir is in essence a call for the prudent management of risk. Contemporary risk management revolves around financial engineering, the building blocks of which are financial derivatives. Despite the proven efficacy of derivatives in the management of risk in the conventional space, shariah scholars appear to be suspicious and uneasy with their use in IBF. Some have imposed outright prohibition of their use. This paper re-examines the issue of contemporary derivative instruments and shariah compliance. The shariah compatibility of derivatives is shown in a number of ways. First, by way of qualitative evaluation of whether derivatives can be made to comply with the key prohibitions of the sharia. Second, by way of comparing the payoff profiles of derivatives with risk sharing finance and Bai Salam contracts. Finally, the equivalence between shariah compliant derivatives like the IPRS and Islamic FX Currency Forwards with conventional ones is presented.

Bacha, Obiyathulla Ismath

2013-04-01

301

Synthesis of new polysialic acid derivatives.  

PubMed

In this paper we report the first synthesis of novel polysialic acid derivatives which is initiated by treatment of polysialic acid with EDC-HCl to yield the inter-residual delta-lactone. Subsequent reaction with amines or hydrazine gives the corresponding polysialic acid amides and hydrazide. Alkylation of the tetrabutylammonium salt of polysialic acid yields polysialic acid esters. In contrast a variety of N-derivatives of polysialic acid can be prepared starting from deacetylated polysialic acid. The N-derivatives prepared in this communication can be used for the Cu-catalyzed as well as Cu-free "click" chemistry. PMID:20602419

Su, Yi; Kasper, Cornelia; Kirschning, Andreas; Dräger, Gerald; Berski, Silke

2010-09-01

302

The Theory of Quaternion Matrix Derivatives  

E-print Network

A systematic theory is introduced for calculating the derivatives of quaternion matrix function with respect to quaternion matrix variables. The proposed methodology is equipped with the matrix product rule and chain rule and it is able to handle both analytic and nonanalytic functions. This corrects a flaw in the existing methods, that is, the incorrect use of the traditional product rule. In the framework introduced, the derivatives of quaternion matrix functions can be calculated directly without the differential of this function. Key results are summarized in tables. Several examples show how the quaternion matrix derivatives can be used as an important tool for solving problems related to signal processing.

Dongpo Xu; Danilo P. Mandic

2014-10-01

303

New fluorescent cytidine 5'-phosphate derivatives.  

PubMed Central

Interaction of cytidine 5'-phosphate with chloroacetone or p-tosyloxyacetone leads to 2-methyl-5,6-dihydro-5-oxo-6-(5-0-phospho-beta-D-ribofuranosyl)-imidazo/1,2-c/pyrimidine (2-methylethenocytidine 5'-phosphate) whereas analogous reaction with phenacyl bromide produces similar 2-phenyl-derivative. The bicyclic nucleotides obtained showed significant UV absorption at long wavelength where common nucleotides and proteins exhibited no absorption. These derivatives are highly fluorescent when heterocyclic ring is protonated. The absorption and fluorescent properties of the substituted ethenocytidine 5'-phosphoate derivatives seem to be suitable for their use as fluorescent probes or labels in biochemical studies. PMID:7772

Kochetkov, N K; Shibaev, V N; Kost, A A; Razjivin, A P; Borisov AYu

1976-01-01

304

Analysis and the Derivation of Valid Objectives  

ERIC Educational Resources Information Center

Author states that "to the extent that behavioral objectives are derived from an analysis of relatively broad objectives, they can serve as valid criteria which enable our students to avoid trivia." (Author)

Tiemann, Philip W.

1973-01-01

305

Tri and tetrahydroxycoumarin derivatives from Tetraphis pellucida  

Microsoft Academic Search

From gametophytes of Tetraphis pellucida have been isolated eight different tri- and tetrahydroxycoumarin derivatives; three of them are new natural products, the structures of which were elucidated spectroscopically. The taxonomic relevance of the results is discussed.

Marion Jung; Hans Geiger; Hans Dietmar Zinsmeister

1995-01-01

306

SCM Forcing Data Derived from NWP Analyses  

DOE Data Explorer

Forcing data, suitable for use with single column models (SCMs) and cloud resolving models (CRMs), have been derived from NWP analyses for the ARM (Atmospheric Radiation Measurement) Tropical Western Pacific (TWP) sites of Manus Island and Nauru.

Jakob, Christian

307

MANGROVE-DERIVED NUTRIENTS AND CORAL REEFS  

EPA Science Inventory

Understanding the consequences of the declining global cover of mangroves due to anthropogenic disturbance necessitates consideration of how mangrove-derived nutrients contribute to threatened coral reef systems. We sampled potential sources of organic matter and a suite of sessi...

308

Phytol-Derived Novel Isoprenoid Immunostimulants  

PubMed Central

This review describes the adjuvanticity of novel diterpenoids (synthetic phytol derivatives) compared to some commercially available adjuvants. The efficacy of the phytol-derived immunostimulants was evaluated in terms of their ability to activate innate immunity, amplify various antigen-specific immune responses, and engender immunological memory with no discernible adverse effects in both competent and immune-deficient mice. The profile that emerges out of these studies reveals that the phytol derivatives are excellent immunostimulants, superior to a number of commercial adjuvants in terms of long-term memory induction and activation of both innate and acquired immunity. Additionally, the phytol-derived compounds have no cumulative inflammatory or toxic effects even in immuno-compromised mice. PMID:22566931

Chowdhury, Roshni Roy; Ghosh, Swapan K.

2012-01-01

309

Cellulose Derivatives for Water Repellent Properties  

Technology Transfer Automated Retrieval System (TEKTRAN)

Synthesis and structural characterizations of nitro-benzyl cellulose, amino-benzyl cellulose and pentafluoro –benzyl cellulose were carried out. Cellulose derivatives were synthesized by etherification process in lithium chloride/N,N-dimethylacetamide homogeneous solution. Nitrobenzylation was effec...

310

Superconformal Symmetry and Higher-Derivative Lagrangians  

NASA Astrophysics Data System (ADS)

Superconformal methods are useful to build invariant actions in supergravity. We have a good insight in the possibilities of actions that are at most quadratic in spacetime derivatives, but insight in general higher-derivative actions is missing. Recently higher-derivative actions got more attention for several applications. One of these is the understanding of finiteness of loop computations in supergravities. Divergences can only occur if invariant counterterms or anomalies exist. One can wonder whether conformal symmetry might also play a role in this context. In order to construct higher-derivative supergravities with the conformal methods, one should first get more insight in such rigid supersymmetric actions with extra fermionic symmetries. We show how Dirac-Born-Infeld actions with Volkov-Akulov supersymmetries can be constructed in all orders.

Van Proeyen, Antoine

311

45 CFR 601.5 - Derivative classification.  

Code of Federal Regulations, 2013 CFR

...Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CLASSIFICATION AND DECLASSIFICATION...classified, and marking the newly developed material consistent with the marking of the...classification markings derived from source material or as directed by a classification...

2013-10-01

312

45 CFR 601.5 - Derivative classification.  

Code of Federal Regulations, 2014 CFR

...Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CLASSIFICATION AND DECLASSIFICATION...classified, and marking the newly developed material consistent with the marking of the...classification markings derived from source material or as directed by a classification...

2014-10-01

313

45 CFR 601.5 - Derivative classification.  

Code of Federal Regulations, 2012 CFR

...Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CLASSIFICATION AND DECLASSIFICATION...classified, and marking the newly developed material consistent with the marking of the...classification markings derived from source material or as directed by a classification...

2012-10-01

314

45 CFR 601.5 - Derivative classification.  

Code of Federal Regulations, 2011 CFR

...Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CLASSIFICATION AND DECLASSIFICATION...classified, and marking the newly developed material consistent with the marking of the...classification markings derived from source material or as directed by a classification...

2011-10-01

315

Concise Derivation of the Rotational Partition Function.  

ERIC Educational Resources Information Center

Derived is the classical partition function for the rotation of a rigid asymmetric molecule, by a transformation of variables in the phase integral circumventing the cumbersome manipulation of the canonical prescription. (Author/GA)

Hynne, F.; Andersen, Knud

1979-01-01

316

Real estate derivatives : products and prospects  

E-print Network

The paper reviews the development, structure and trade of past real estate equity hedging instruments. The reviewed products represent a wide array of real estate derivatives, covering multiple property types, index ...

Eisenberg, Oriel

2013-01-01

317

Direct synthesis of pyridine and pyrimidine derivatives  

E-print Network

I. Synthesis of Substituted Pyridine Derivatives via the Ruthenium-Catalyzed Cycloisomerization of 3-Azadienynes. The two-step conversion of various N-vinyl and N-aryl amides to the corresponding substituted pyridines and ...

Hill, Matthew D. (Matthew Dennis)

2008-01-01

318

45 CFR 601.5 - Derivative classification.  

Code of Federal Regulations, 2010 CFR

...Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CLASSIFICATION AND DECLASSIFICATION...classified, and marking the newly developed material consistent with the marking of the...classification markings derived from source material or as directed by a classification...

2010-10-01

319

Conflicts of Interest in Derivatives Clearing  

Microsoft Academic Search

[Excerpt] The financial crisis implicated the over-the-counter (OTC) derivatives market as a source of systemic risk. In the wake of the crisis, lawmakers sought to reduce systemic risk to the financial system by regulating this market. One of the reforms that Congress introduced in the Dodd-Frank Act (P.L. 111-203) was mandatory clearing of OTC derivatives through clearinghouses, in an effort

Rena S Miller

2011-01-01

320

Synthesis and fungitoxicity of some pyrimidine derivatives  

Microsoft Academic Search

A series of 12 pyrimidine derivatives were prepared and tested in vitro against growth, sporulation and nucleic acids ofFusarium oxysporum f. sp.lycopersici andHelminthosporium oryzae. Introduction of thiazole ring together with two aryl groups to 2-aminopyrimidine induced drastic toxicity for both fungi.\\u000a Pyrimidine derivatives with aryl groups were less toxic. Nitro groups were found to enhance the toxicity of the pyrimidine

Salama A. Ouf; Sherif M. Sherif

1993-01-01

321

Synthesis and fungitoxicity of some pyrimidine derivatives  

Microsoft Academic Search

A series of 12 pyrimidine derivatives were prepared and testedin vitro against growth, sporulation and nucleic acid content ofFusarium oxysporum f. sp.lycopersici andHelminthosporium oryzae. Introduction of a thiazole ring together with two aryl groups into 2-aminopyrimidine brought about drastic toxicity for\\u000a both fungi. Pyrimidine derivatives with aryl groups alone were less toxic. Nitro groups were found to enhance the toxicity

S. A. Ouf; S. M. Sherif

1993-01-01

322

Derived categories and stacks in physics  

E-print Network

In this note we review how both derived categories and stacks enter physics. The physical realization of each has many formal similarities. For example, in both cases, equivalences are realized via renormalization group flow: in the case of derived categories, (boundary) renormalization group flow realizes the mathematical procedure of localization on quasi-isomorphisms, and in the case of stacks, worldsheet renormalization group flow realizes presentation-independence. For both, we outline current technical issues and applications.

E. Sharpe

2006-09-13

323

Siderophore production by marine-derived fungi  

Microsoft Academic Search

Siderophore production by marine-derived fungi has not been extensively explored. Three studies have investigated the ability\\u000a of marine-derived fungi to produce siderophores in response to iron limitation [(Vala et al. in Indian J Mar Sci 29:339–340,\\u000a 2000; Can J Microbiol 52:603–607, 2006); Baakza et al. in J Exp Mar Biol Ecol 311:1–9, 2004]. In all, 24 of 28 marine fungal

Brian Holinsworth; Jessica D. Martin

2009-01-01

324

Synthesis and antimycobacterial activity of calpinactam derivatives.  

PubMed

Synthesis of calpinactam 1, a fungal antimycobacterial metabolite, utilizing solid-phase peptide synthesis is described. To explore the structure-activity relationships of 1, its derivatives with different amino acids were also synthesized on the basis of the same synthetic strategy. These derivatives were examined for antimycobacterial activity against Mycobacterium smegmatis. Among them, only peptide 6d having d-Ala in place of d-Glu showed moderate activity. PMID:23116887

Nagai, Kenichiro; Koyama, Nobuhiro; Sato, Noriko; Yanagisawa, Chisato; Tomoda, Hiroshi

2012-12-15

325

Deriving Mathisson - Papapetrou equations from relativistic pseudomechanics  

E-print Network

It is shown that the equations of motion of a test point particle with spin in a given gravitational field, so called Mathisson - Papapetrou equations, can be derived from Euler - Lagrange equations of the relativistic pseudomechanics -- relativistic mechanics, which side by side uses the conventional (commuting) and Grassmannian (anticommuting) variables. In this approach the known difficulties of the Mathisson - Papapetrou equations, namely, the problem of the choice of supplementary conditions and the problem of higher derivatives are not appear.

R. R. Lompay

2005-03-12

326

New stilbene derivatives from Calligonum leucocladum.  

PubMed

Two new stilbene derivatives, (E)-resveratrol 3-(6' '-galloyl)-O-beta-D-glucopyranoside (1) and (E)-resveratrol 3-(4' '-acetyl)-O-beta-D-xylopyranoside (2), and five known stilbene derivatives (3-7) were isolated from the dried aerial parts of Calligonum leucocladum. Their structures were established on the basis of spectroscopic evidence. Compound 1 showed antioxidant activity and a restorative effect of the inhibition of oxacillin to oxacillin/methicillin-resistant Staphylococcus aureus. PMID:15217293

Okasaka, Mamoru; Takaishi, Yoshihisa; Kogure, Kentarou; Fukuzawa, Kenji; Shibata, Hirohumi; Higuti, Tomihiko; Honda, Gisho; Ito, Michiho; Kodzhimatov, Olimjon K; Ashurmetov, Ozodbek

2004-06-01

327

Iron coordination by catechol derivative antioxidants.  

PubMed

Iron complexes of nitrocatechols with different substituent groups [1: -CH = CR2; 2: -CH2-CHR2; 3: -CH = CR'(R")] were synthesized and their effects on iron-induced free radical reactions of biological importance investigated. Catechol and nitrocatechol derivatives effectively inhibited iron-induced lipid peroxide-dependent lipid peroxidation. In the Fenton-like reaction, iron-catechol generated hydroxyl radicals more strongly than did iron citrate, and iron-nitrocatechol derivative 2 generated a small amount of hydroxyl radicals. The iron complexes of derivatives 1 and 3 did not generate hydroxyl radicals. Iron-catechol had the highest ratio of reduction to oxidation rate constants and the second was iron-nitrocatechol 2, suggesting that iron chelated by nitrocatechols 1 and 3 may be most difficult to reduce. To elucidate the structure and physical properties of the iron complexes, UV/vis absorption spectroscopic, ESR and 1H NMR studies were performed in aqueous and DMSO solutions. In aqueous solution at pH 7.4, iron complexes of the nitrocatechol derivatives were high-spin tris(nitrocatecholato)ferrate(III) with a characteristic ligand-to-metal charge transfer absorbance (pi -> d pi). The lambda max of iron-nitrocatechol derivative 2 was shorter than those of iron-nitrocatechol derivatives 1 and 3, suggesting that the reduction potential of iron-nitrocatechol 2 is higher than that of iron-nitrocatechols 1 and 3. Nitrocatechol derivatives with a conjugation structure can sequester the chelated iron more effectively than catechol and the derivative without the conjugation against free radical generation by keeping the iron in the ferric state, probably because of the reduction potentials. PMID:8630099

Kawabata, T; Schepkin, V; Haramaki, N; Phadke, R S; Packer, L

1996-06-14

328

Crystallisation and crystal forms of carbohydrate derivatives  

NASA Astrophysics Data System (ADS)

This thesis is focused on the synthesis and solid state analysis of carbohydrate derivatives, including many novel compounds. Although the synthetic chemistry surrounding carbohydrates is well established in the literature, the crystal chemistry of carbohydrates is less well studied. Therefore this research aims to improve understanding of the solid state properties of carbohydrate derivatives through gaining more information on their supramolecular bonding. Chapter One focuses on an introduction to the solid state of organic compounds, with a background to crystallisation, including issues that can arise during crystal growth. Chapter Two is based on glucopyranuronate derivatives which are understudied in terms of their solid state forms. This chapter reports on the formation of novel glucuronamides and utilising the functionality of the amide bond for crystallisation. TEMPO oxidation was completed to form glucopyranuronates by oxidation of the primary alcohol groups of glucosides to the carboxylic acid derivatives, to increase functionality for enhanced crystal growth. Chapter Three reports on the synthesis of glucopyranoside derivatives by O-glycosylation reactions and displays crystal structures, including a number of previously unsolved acetate protected and deprotected crystal structures. More complex glycoside derivatives were also researched in an aim to study the resultant supramolecular motifs. Chapter Four contains the synthesis of aryl cellobioside derivatives including the novel crystal structures that were solved for the acetate protected and deprotected compounds. Research was carried out to determine if 1-deoxycellodextrins could act as putative isostructures for cellulose. Our research displays the presence of isostructural references with 1-deoxycellotriose shown to be similar to cellulose III11, 1-deoxycellotetraose correlates with cellulose IV11 and 1-deoxycellopentose shows isostructurality similar to that of cellulose II. Chapter Five contains the full experimental details and spectral characterisation of all novel compounds synthesised in this project and relevant crystallographic information.

Lennon, Lorna

329

Novel benzimidazole derivatives as expected anticancer agents.  

PubMed

A series of 1-(1H-benzimidazol-2-yl)-3-(substituted)-2-propen-1-one and its 1-methyl analogues 2c-h were synthesized and cyclized with different reagents such as ethyl cyanoacetate, thiourea, hydroxylamine hydrochloride, guanidinium sulfate, methylhydrazine, phenylhydrazine and/or hydrogen peroxide in different reactions to produce pyridones 3a,b, pyrimidinethione 4a,b, isoxazole 5a,b, aminopyrimidine 6a,b, pyrazoline 7i-k and epoxy derivative 8, respectively. Acetohydrazide 10 reacted with formic acid, acetic anhydride, carbon disulfide and/or thiosemicarbazide to yield compounds 11-19. Also compound 21a,b was condensed with different monosaccharides to yield the corresponding N-glycoside Schiff's bases derivatives 22a-h, which upon treatment with acetic anhydride afforded 23a-h derivatives. The anticancer activity of some of the newly synthesized compounds was evaluated against HEPG2 (human liver carcinoma cell line) and PC12 (pheochromocytoma of the rat adrenal medulla) cells. Benzimidazole-2-isoxazole 5a derivative exhibited high potency against HEPG2 and PC12 cells. Benzimidazole chalcones 2c,e, benzimidazole mercaptoacetohydrazide 14 and benzimidazole thiosemicarbazide 15a,b derivatives gave high potency against PC12 cells. PMID:21796934

Nofal, Zienab M; Soliman, Elsyed A; Abd El-Karim, Somaia S; El Zahar, Magdy I; Srour, Aladdin M; Sethumadhavan, Shalini; Maher, Timothy J

2011-01-01

330

Deriving Framework Usages Based on Behavioral Models  

NASA Astrophysics Data System (ADS)

One of the critical issue in framework-based software development is a huge introduction cost caused by technical gap between developers and users of frameworks. This paper proposes a technique for deriving framework usages to implement a given requirements specification. By using the derived usages, the users can use the frameworks without understanding the framework in detail. Requirements specifications which describe definite behavioral requirements cannot be related to frameworks in as-is since the frameworks do not have definite control structure so that the users can customize them to suit given requirements specifications. To cope with this issue, a new technique based on satisfiability problems (SAT) is employed to derive the control structures of the framework model. In the proposed technique, requirements specifications and frameworks are modeled based on Labeled Transition Systems (LTSs) with branch conditions represented by predicates. Truth assignments of the branch conditions in the framework models are not given initially for representing the customizable control structure. The derivation of truth assignments of the branch conditions is regarded as the SAT by assuming relations between termination states of the requirements specification model and ones of the framework model. This derivation technique is incorporated into a technique we have proposed previously for relating actions of requirements specifications to ones of frameworks. Furthermore, this paper discuss a case study of typical use cases in e-commerce systems.

Zenmyo, Teruyoshi; Kobayashi, Takashi; Saeki, Motoshi

331

Structure activity relationship of brevenal hydrazide derivatives.  

PubMed

Brevenal is a ladder frame polyether produced by the dinoflagellate Karenia brevis. This organism is also responsible for the production of the neurotoxic compounds known as brevetoxins. Ingestion or inhalation of the brevetoxins leads to adverse effects such as gastrointestinal maladies and bronchoconstriction. Brevenal shows antagonistic behavior to the brevetoxins and shows beneficial attributes when administered alone. For example, in an asthmatic sheep model, brevenal has been shown to increase tracheal mucosal velocity, an attribute which has led to its development as a potential treatment for Cystic Fibrosis. The mechanism of action of brevenal is poorly understood and the exact binding site has not been elucidated. In an attempt to further understand the mechanism of action of brevenal and potentially develop a second generation drug candidate, a series of brevenal derivatives were prepared through modification of the aldehyde moiety. These derivatives include aliphatic, aromatic and heteroaromatic hydrazide derivatives. The brevenal derivatives were tested using in vitro synaptosome binding assays to determine the ability of the compounds to displace brevetoxin and brevenal from their native receptors. A sheep inhalation model was used to determine if instillation of the brevenal derivatives resulted in bronchoconstriction. Only small modifications were tolerated, with larger moieties leading to loss of affinity for the brevenal receptor and bronchoconstriction in the sheep model. PMID:24686558

Goodman, Allan; McCall, Jennifer R; Jacocks, Henry M; Thompson, Alysha; Baden, Daniel; Abraham, William M; Bourdelais, Andrea

2014-04-01

332

New steroid derivative with hypoglycemic activity  

PubMed Central

Data indicates that some steroid derivatives may induce changes on glucose levels; nevertheless, data are very confusing. Therefore, more pharmacological data are needed to characterize the activity induced by the steroid derivatives on glucose levels. The aim of this study was to synthesize a new steroid derivative for evaluate its hypoglycemic activity. The effects of steroid derivative on glucose concentration were evaluated in a diabetic animal model using glibenclamide and metformin as controls. In addition, the pregnenolone-dihydrotestosterone conjugate was bound to Tc-99m using radioimmunoassay methods, to evaluate the pharmacokinetics of the steroid derivative over time. The results showed that the pregnenolone-dihydrotestosterone conjugate induces changes on the glucose levels in similar form than glibenclamide. Other data showed that the biodistribution of Tc-99m-steroid derivativein brain was higher in comparison with spleen, stomach, intestine liver and kidney. In conclusion, the pregnenolone-dihydrotestosterone conjugate exerts hypoglycemic activity and this phenomenon could depend of its physicochemical properties which could be related to the degree of lipophilicity of the steroidderivative.

Lauro, Figueroa-Valverde; Francisco, Díaz-Cedillo; Lenin, Hau-Heredia; Elodia, García-Cervera; Eduardo, Pool-Gómez; Marcela, Rosas-Nexticapa; Bety, Sarabia-Alcocer

2014-01-01

333

Derivation of Completely Cell Culture-Derived Mice from Early-Passage Embryonic Stem Cells  

Microsoft Academic Search

Several newly generated mouse embryonic stem (ES) cell lines were tested for their ability to produce completely ES cell-derived mice at early passage numbers by ES cell leftrightarrow tetraploid embryo aggregation. One line, designated R1, produced live offspring which were completely ES cell-derived as judged by isoenzyme analysis and coat color. These cell culture-derived animals were normal, viable, and fertile.

Andras Nagy; Janet Rossant; Reka Nagy; Wanda Abramow-Newerly; John C. Roder

1993-01-01

334

Annihilation-Derivative, Creation-Derivative and Representation of Quantum Martingales  

Microsoft Academic Search

On the basis of the quantum white noise theory we introduce the notion of creation- and annihilation-derivatives of Fock space\\u000a operators and study the differentiability of white noise operators. We define the Hitsuda–Skorohod quantum stochastic integrals\\u000a by the adjoint actions of quantum stochastic gradients and show explicit formulas for their creation- and annihilation-derivatives.\\u000a As an application, we derive direct formulas

Un Cig Ji; Nobuaki Obata

2009-01-01

335

2-Methoxy-benzaldehyde 2,4-dinitro-phenyl-hydrazone.  

PubMed

In the title compound, C(14)H(12)N(4)O(5), an intra-molecular N-H?O hydrogen bond generates an S(6) ring motif. The dihedral angle between the two benzene rings is 3.91?(3)°, which shows the mol-ecule is almost planar. The para-nitro group is twisted from the benzene ring to which it is attached, making a dihedral angle of 8.50?(9)°. In the crystal structure, mol-ecules are linked together by inter-molecular C-H?O and inter-molecular three-centred O?O [2.8646?(12)-2.9213?(11)?Å] and O?N [3.0518?(11)?Å] inter-actions. The crystal structure is further stabilized by inter-molecular ?-? inter-actions [centroid-to-centroid distances 3.5708?(6)-3.9728?(12)?Å]. PMID:21581863

Fun, Hoong-Kun; Kia, Reza; Kargar, Hadi

2009-01-01

336

Structure/Enantioselectivity Study of the Asymmetric Addition of Trimethylsilylcyanide to Benzaldehyde  

E-print Network

of achiral Lewis acid catalysts.6 Subsequent advances allow addition of trimethylsilylcyanide to carbonyl groups in an enantioselective fashion using chiral Lewis acid catalysts.7-9 The products of this reaction York, 1994. (5) Gregory, R. J. H. Chem. Rev. 1999, 99, 3649-3682. (6) Evans, D. A.; Carrol, G. L

Walsh, Patrick J.

337

Micropropagation of Hemidesmus indicus for cultivation and production of 2-hydroxy 4-methoxy benzaldehyde  

Microsoft Academic Search

Caulogenic responses of various explant types from 12-month-old plants of Hemidesmus indicus were tested. Second and third visible nodes (0.5 cm) from the apex and root segments (0.5 cm) were the most and least regenerative\\u000a respectively, with the formation of 9.37 and 2.6 shoots in 4 weeks on half strength MS medium supplemented with 2.22 ?M BA\\u000a and 1.07 ?M

S. Sreekumar; S. Seeni; P. Pushpangadan

2000-01-01

338

4-Hy­droxy-3-meth­oxy­benzaldehyde 4-phenyl­thio­semicarbazone  

PubMed Central

In the title compound, C15H15N3O2S, the central C—N—N—C unit has an anti conformation [torsion angle = ?170.17?(15)°]. The phenyl substituent is oriented perpendicular to this unit [dihedral angle of 89.2?(1)°], whereas the substituted ring is rotated out of this plane by only 18.86?(17)°. In the crystal, mol­ecules are linked by pairs of N—H?S hydrogen bonds into inversion dimers that are further connected via N—H?O and O—H?S hydrogen bonds into a three-dimensional network. PMID:24764990

de Oliveira, Adriano Bof; Feitosa, Bárbara Regina Santos; Näther, Christian; Jess, Inke

2014-01-01

339

4-Hy­droxy-3-meth­oxy­benzaldehyde 4-ethyl­thio­semicarbazone  

PubMed Central

In the crystal structure of the title compound, C11H15N3O2S, the C—N—N—C and C—N—C—C torsion angles involving the benzene ring and ethyl group are 11.91?(15) and 99.4?(2)°, respectively. An intra­molecular N—H?N hydrogen bond is observed. In the crystal, mol­ecules are linked via N—H?O and N—H?S hydrogen bonds into a three-dimensional hydrogen bonded network. Finally, the molecules show a herringbone arrangement when viewed along the a axis. PMID:25249915

de Oliveira, Adriano Bof; Beck, Johannes; Daniels, Jörg; Feitosa, Bárbara Regina Santos

2014-01-01

340

DECREASE IN OVALBUMIN-INDUCED PULMONARY ALLERGIC RESPONSE BY BENZALDEHYDE BUT NOT ACETALDEHYDE  

E-print Network

Carbonyl compounds, particularly aldehydes, are receiving increasing attention as air pollutants because A 65, 14 (2002) 995-1012" DOI : 10.1080/00984100290071199 #12;2/27 ABSTRACT The pulmonary effects of alveolar macrophages in animals exposed to acetaldehyde. In sensitized GPs, exposure to acetaldehyde

Boyer, Edmond

341

Dramatic catalyst evolution in the asymmetric addition of diethylzinc to benzaldehyde  

E-print Network

Received 10 November 2004; revised 11 February 2005; accepted 4 March 2005 Available online 4 May 2005 2005 Elsevier Ltd. All rights reserved. 1. Introduction Asymmetric catalysts can evolve over the course (2005) 6442­6446 0040­4020/$ - see front matter q 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j

Walsh, Patrick J.

342

Second derivatives for approximate spin projection methods.  

PubMed

The use of broken-symmetry electronic structure methods is required in order to obtain correct behavior of electronically strained open-shell systems, such as transition states, biradicals, and transition metals. This approach often has issues with spin contamination, which can lead to significant errors in predicted energies, geometries, and properties. Approximate projection schemes are able to correct for spin contamination and can often yield improved results. To fully make use of these methods and to carry out exploration of the potential energy surface, it is desirable to develop an efficient second energy derivative theory. In this paper, we formulate the analytical second derivatives for the Yamaguchi approximate projection scheme, building on recent work that has yielded an efficient implementation of the analytical first derivatives. PMID:25662635

Thompson, Lee M; Hratchian, Hrant P

2015-02-01

343

Synthesis and properties of novel psoralen derivatives  

SciTech Connect

The authors have synthesized a set of new trimethylpsoralen derivatives that are characterized by a chain extending from the 4'-position of the furan ring and linked to this ring by an aminomethylene group. The nature of the side chain can be varied widely. In these derivatives, the chains contain either amino or ethylene oxide units for enhanced water solubility and allow the introduction of a thiol or amine group to nucleic acids. These compounds represent the first set of thiolated psoralen derivatives, and their usefulness is demonstrated in several nucleic acid cross-linking experiments. The reagents can be used to create both intraduplex reversible cross-links between the two single-strand partners in a DNA double helix and interduplex reversible cross-links between two DNA double helices.

Goldenberg, M.; Welsh, J.; Haas, R.; Rideout, D.C.; Cantor, C.R.

1988-09-06

344

Gateaux and Frechet Derivative in Intuitionistic Fuzzy Normed Linear spaces  

E-print Network

Intuitionistic Fuzzy derivative, Intuitionistic Fuzzy Gateaux derivative, Intuitionistic Fuzzy Fr\\'{e}chet derivative are defined and a few of their properties are studied. The relation between Intuitionistic Fuzzy Gateaux derivative and Intuitionistic Fuzzy Fr\\'{e}chet derivative are emphasized.

B. Dinda; T. K. Samanta; U. K. Bera

2010-09-11

345

Talbot interferometer for radial and lateral derivatives.  

PubMed

The theory and experimental evidence of a shearing interferometer based on the Talbot effect are presented. Multiple-shearing interferences are obtained that can be reduced to triple-shearing or doubleshearing interferences by the addition of simple spatial filtering. When the shear is less than the width of the details in the object, these interferences become either the second or first derivative of the object under test, respectively. Either lateral or constant radial shear can be introduced by choosing Ronchi rulings or circular gratings. Thus both lateral and radial derivatives are easily obtained. If white light is used as a source, color fringes of high contrast are observed. PMID:20119380

Silva, D E

1972-11-01

346

Special Relativity Derived from Spacetime Magma  

PubMed Central

We present a derivation of relativistic spacetime largely untethered from specific physical considerations, in constrast to the many physically-based derivations that have appeared in the last few decades. The argument proceeds from the inherent magma (groupoid) existing on the union of spacetime frame components and Euclidean which is consistent with an “inversion symmetry” constraint from which the Minkowski norm results. In this context, the latter is also characterized as one member of a class of “inverse norms” which play major roles with respect to various unital -algebras more generally. PMID:24959889

Greensite, Fred

2014-01-01

347

Geometric derivation of the quantum speed limit  

SciTech Connect

The Mandelstam-Tamm and Margolus-Levitin inequalities play an important role in the study of quantum-mechanical processes in nature since they provide general limits on the speed of dynamical evolution. However, to date there has been only one derivation of the Margolus-Levitin inequality. In this paper, alternative geometric derivations for both inequalities are obtained from the statistical distance between quantum states. The inequalities are shown to hold for unitary evolution of pure and mixed states, and a counterexample to the inequalities is given for evolution described by completely positive trace-preserving maps. The counterexample shows that there is no quantum speed limit for nonunitary evolution.

Jones, Philip J.; Kok, Pieter [Department of Physics and Astronomy, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom)

2010-08-15

348

Monoterpene citral derivatives as potential antimalarials.  

PubMed

Conjugated acid derivatives containing nitrogen have been synthesized from the simple acyclic monoterpene citral, using various reactions, including Wittig, Baylis Hillman, amide and ester condensations. Similarly, amine peroxides were synthesized by subjecting citral to Mannich type reaction with amines and t-butyl hydroperoxide. Molecules 3-10 were evaluated for antimalarial activity against erythrocytic stages of chloroquine sensitive P. falciparum strain 3D7. Four derivatives displayed interesting activity with an IC50< 2.5 microM, and warrant further investigations. PMID:24689199

Singh, Soni; Khandare, Reena P; Sharma, Manish; Bhasin, Virendra K; Bhat, Sujata V

2014-03-01

349

High ethanol producing derivatives of Thermoanaerobacter ethanolicus  

DOEpatents

Derivatives of the newly discovered microorganism Thermoanaerobacter ethanolicus which under anaerobic and thermophilic conditions continuously ferment substrates such as starch, cellobiose, glucose, xylose and other sugars to produce recoverable amounts of ethanol solving the problem of fermentations yielding low concentrations of ethanol using the parent strain of the microorganism Thermoanaerobacter ethanolicus are disclosed. These new derivatives are ethanol tolerant up to 10% (v/v) ethanol during fermentation. The process includes the use of an aqueous fermentation medium, containing the substrate at a substrate concentration greater than 1% (w/v).

Ljungdahl, L.G.; Carriera, L.H.

1983-05-24

350

Elevation Derivatives for Mojave Desert Tortoise Habitat  

USGS Publications Warehouse

This report describes the methods used to derive various elevation-derivative grids that were inputted to the Mojave Desert Tortoise Habitat model (L. Gass and others, unpub. data). These grids, which capture information on surface roughness and topographic characteristics, are a subset of the environmental datasets evaluated for the tortoise habitat model. This habitat model is of major importance to the U.S. Fish and Wildlife Service, which is charged with management of this threatened population, including relocating displaced tortoises to areas identified as suitable habitat.

Wallace, Cynthia S.A.; Gass, Leila

2008-01-01

351

Special relativity derived from spacetime magma.  

PubMed

We present a derivation of relativistic spacetime largely untethered from specific physical considerations, in constrast to the many physically-based derivations that have appeared in the last few decades. The argument proceeds from the inherent magma (groupoid) existing on the union of spacetime frame components [Formula: see text] and Euclidean [Formula: see text] which is consistent with an "inversion symmetry" constraint from which the Minkowski norm results. In this context, the latter is also characterized as one member of a class of "inverse norms" which play major roles with respect to various unital [Formula: see text]-algebras more generally. PMID:24959889

Greensite, Fred

2014-01-01

352

Vitamin B12 derivatives for orthogonal functionalization.  

PubMed

The synthesis of vitamin B12 derivatives for selective orthogonal conjugation at both the Co center and 5'-OH is reported. Newly developed, reduction-free, direct alkynylation of vitamin B12 at the central cobalt ion proved to be versatile, with the formed acetylides, unlike other metalloorganic derivatives, showing remarkable heat and light stability, thus making them promising candidates as a drug carrier. Subsequently, high-yielding functionalization can be achieved via a sequence of selective [1,3] dipolar azide-alkyne cycloadditions (AACs) or carbamate formation followed by AAC. PMID:25046078

Chromi?ski, Miko?aj; Lewalska, Agnieszka; Karczewski, Maksymilian; Gryko, Dorota

2014-08-15

353

SYNTHESIS AND CHARACTERIZATION OF SOME ORGANIC CARBONATES DERIVED FROM VEGETABLE OILS AND THEIR DERIVATIVES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Vegetable oils, their derivatives, and glycerin represent renewable raw materials that are firmly established components in many industrial products. Their use continues to be of interest to many researchers and the development of approaches to functionalize these compounds to derive oleochemicals ...

354

40 CFR 721.2025 - Substituted phenylimino carbamate derivative.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Substituted phenylimino carbamate derivative. 721.2025 Section 721...721.2025 Substituted phenylimino carbamate derivative. (a) Chemical substance...generically as a substituted phenylimino carbamate derivative (PMN P-91-487)...

2013-07-01

355

40 CFR 721.2025 - Substituted phenylimino carbamate derivative.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Substituted phenylimino carbamate derivative. 721.2025 Section 721...721.2025 Substituted phenylimino carbamate derivative. (a) Chemical substance...generically as a substituted phenylimino carbamate derivative (PMN P-91-487)...

2011-07-01

356

40 CFR 721.2025 - Substituted phenylimino carbamate derivative.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false Substituted phenylimino carbamate derivative. 721.2025 Section 721...721.2025 Substituted phenylimino carbamate derivative. (a) Chemical substance...generically as a substituted phenylimino carbamate derivative (PMN P-91-487)...

2014-07-01

357

40 CFR 721.2025 - Substituted phenylimino carbamate derivative.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Substituted phenylimino carbamate derivative. 721.2025 Section 721...721.2025 Substituted phenylimino carbamate derivative. (a) Chemical substance...generically as a substituted phenylimino carbamate derivative (PMN P-91-487)...

2012-07-01

358

Barriers to growth in the US real estate derivatives market  

E-print Network

Commercial real estate is an important asset class but it does not yet have a well-developed derivatives market in the United States. A derivative is a contract that derives its value from an underlying index or asset. ...

Venter, Jani

2007-01-01

359

75 FR 78185 - Information Management Requirements for Derivatives Clearing Organizations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Information Management Requirements for Derivatives Clearing Organizations AGENCY: Commodity...implement certain core principles for derivatives clearing organizations (DCOs) as amended...execution requirements on standardized derivative products; (3) creating...

2010-12-15

360

78 FR 66639 - Modifications of Certain Derivative Contracts  

Federal Register 2010, 2011, 2012, 2013, 2014

...1545-BK13 Modifications of Certain Derivative Contracts AGENCY: Internal Revenue...the transfer or assignment of certain derivative contracts. The final regulations provide...to the nonassigning counterparty to a derivative contract and an assignee on...

2013-11-06

361

76 FR 51878 - Modifications of Certain Derivative Contracts; Correction  

Federal Register 2010, 2011, 2012, 2013, 2014

...1545-BK14 Modifications of Certain Derivative Contracts; Correction AGENCY: Internal...a transfer or assignment of certain derivative contracts does not result in an exchange...1001-4T Modifications of certain derivative contracts...

2011-08-19

362

40 CFR 721.1760 - Substituted benzotriazole derivatives.  

Code of Federal Regulations, 2010 CFR

... false Substituted benzotriazole derivatives. 721.1760 Section 721.1760...721.1760 Substituted benzotriazole derivatives. (a) Chemical substances and significant...generically as substituted benzotriazole derivatives (PMNs P-93-374 and...

2010-07-01

363

17 CFR 229.1115 - (Item 1115) Certain derivatives instruments.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false (Item 1115) Certain derivatives instruments. 229.1115 Section 229... § 229.1115 (Item 1115) Certain derivatives instruments. This item relates to derivative instruments, such as interest...

2010-04-01

364

14 CFR 1203.501 - Applying derivative classification markings.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Applying derivative classification markings. 1203.501...ADMINISTRATION INFORMATION SECURITY PROGRAM Derivative Classification § 1203.501 Applying derivative classification markings. Persons...

2010-01-01

365

76 FR 51878 - Modifications of Certain Derivative Contracts; Correction  

Federal Register 2010, 2011, 2012, 2013, 2014

...1545-BK14 Modifications of Certain Derivative Contracts; Correction AGENCY: Internal...a transfer or assignment of certain derivative contracts does not result in an exchange...clearinghouse transfers or assigns a derivative contract to another dealer in...

2011-08-19

366

76 FR 43957 - Modifications of Certain Derivative Contracts  

Federal Register 2010, 2011, 2012, 2013, 2014

...1545-BK13 Modifications of Certain Derivative Contracts AGENCY: Internal Revenue...when there is an assignment of certain derivative contracts. The text of those regulations...that the transfer or assignment of a derivative contract in certain situations is...

2011-07-22

367

40 CFR 721.646 - Aminofluoran derivative (generic name).  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Aminofluoran derivative (generic name). 721.646 Section...Substances § 721.646 Aminofluoran derivative (generic name). (a) Chemical...identified generically as aminofluoran derivative (PMN P-95-512) is subject...

2010-07-01

368

40 CFR 721.9740 - Brominated triazine derivative.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Brominated triazine derivative. 721.9740 Section 721.9740... § 721.9740 Brominated triazine derivative. (a) Chemical substance and significant...generically as a brominated triazine derivative (PMN P-91-403) is subject...

2010-07-01

369

14 CFR 1203.500 - Use of derivative classification.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Use of derivative classification. 1203.500 Section...ADMINISTRATION INFORMATION SECURITY PROGRAM Derivative Classification § 1203.500 Use of derivative classification. The...

2010-01-01

370

18 CFR 367.1750 - Account 175, Derivative instrument assets.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Account 175, Derivative instrument assets. 367.1750...Assets § 367.1750 Account 175, Derivative instrument assets. This account must include the amounts paid for derivative instruments, and the change...

2010-04-01

371

76 FR 43892 - Modifications of Certain Derivative Contracts  

Federal Register 2010, 2011, 2012, 2013, 2014

...1545-BK14 Modifications of Certain Derivative Contracts AGENCY: Internal Revenue...a transfer or assignment of certain derivative contracts does not result in an exchange...necessitate the movement of entire books of derivative contracts. In particular, there...

2011-07-22

372

40 CFR 721.10172 - Alkylamide derivative (generic).  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Alkylamide derivative (generic). 721.10172 Section...Substances § 721.10172 Alkylamide derivative (generic). (a) Chemical substance...identified generically as alkylamide derivative (PMN P-03-633) is subject...

2010-07-01

373

17 CFR 240.16a-4 - Derivative securities.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Derivative securities. 240.16a-4 ...Securities Dealers § 240.16a-4 Derivative securities. (a) For purposes of section 16 of the Act, both derivative securities and the...

2010-04-01

374

40 CFR 721.9079 - Dihydro quinacridone derivative (generic).  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Dihydro quinacridone derivative (generic). 721.9079 Section... § 721.9079 Dihydro quinacridone derivative (generic). (a) Chemical substance...identified generically as dihydro quinacridone derivative (PMN P-01-397) is subject...

2010-07-01

375

40 CFR 721.5925 - Bis heterocyclic phenylene derivative (generic).  

Code of Federal Regulations, 2010 CFR

... false Bis heterocyclic phenylene derivative (generic). 721.5925 Section...5925 Bis heterocyclic phenylene derivative (generic). (a) Chemical substance...generically as bis heterocyclic phenylene derivative (PMN P-01-0432) is subject...

2010-07-01

376

18 CFR 367.2440 - Account 244, Derivative instrument liabilities.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Account 244, Derivative instrument liabilities. 367.2440...Liabilities § 367.2440 Account 244, Derivative instrument liabilities. This account...the change in the fair value of all derivative instrument liabilities not...

2010-04-01

377

40 CFR 721.2025 - Substituted phenylimino carbamate derivative.  

Code of Federal Regulations, 2010 CFR

... Substituted phenylimino carbamate derivative. 721.2025 Section 721.2025... Substituted phenylimino carbamate derivative. (a) Chemical substance and significant...as a substituted phenylimino carbamate derivative (PMN P-91-487) is subject...

2010-07-01

378

Two-sided discrete fractional derivatives and systems  

NASA Astrophysics Data System (ADS)

Starting from the discrete-time nabla (forward) and delta (backward) derivatives we introduce a two-sided derivative valid for any order. Its eigenfunction is the normal discrete exponential. This derivative leads to discrete non causal linear systems.

Ortigueira, Manuel D.

2012-09-01

379

Nonlinear Frechet derivative and its De Wolf approximation  

E-print Network

We introduce and derive the nonlinear Frechet derivative for the acoustic wave equation. It turns out that the high order Frechet derivatives can be realized by consecutive applications of the scattering operator and a ...

Wu, Ru-Shan

2012-01-01

380

Tectonic plate motions derived from Lageos  

Microsoft Academic Search

Five years of laser data (1984-88) between the Lageos satellite and the ground station network based on precise monthly computations of the Lageos satellite are analyzed to recover tectonic motions affecting the stations. A global inversion over this period provides solutions for absolute velocities in latitude and longitude of a selected subset of 14 stations. Relative horizontal velocities are derived

R. Biancale; A. Cazenave; K. Dominh

1991-01-01

381

Deriving Production Rules for Incremental View Maintenance  

Microsoft Academic Search

. It is widely recognized that production rules indatabase systems can be used to automatically maintain deriveddata such as views. However, writing a correct set ofrules for efficiently maintaining a given view can be a difficultand ad-hoc process. We provide a facility whereby a userdefines a view as an SQL select expression, from which thesystem automatically derives set-oriented production rulesthat

Stefano Ceri; Jennifer Widom

1991-01-01

382

Derivation of physically motivated wind speed scales  

Microsoft Academic Search

A class of new wind speed scales is proposed in which the relevant scaling factors are derived from physical quantities like mass flux density, energy density (pressure), or energy flux density. Hence, they are called Energy- or E-scales, and can be applied to wind speeds of any intensity. It is shown that the Mach scale is a special case of

Nikolai Dotzek

2009-01-01

383

CORRESPONDENCE Brain-Derived Neurotrophic Factor, Serotonin  

E-print Network

on Kaufman et al. To the Editor: Brain-derived neurotrophic factor (BDNF) and serotonin transporter (SERT-like behavior in animals (Berton et al. 2006). A recent study has examined BDNF/SERT genes interactions in depressed children, reporting that a combination of met-BDNF allele with two short SERT alleles

Kalueff, Allan V.

384

Curcumin derivatives as HIV-1 protease inhibitors  

SciTech Connect

Curcumin, a non-toxic natural compound from Curcuma longa, has been found to be an HIV-1 protease inhibitor. Some of its derivatives were synthesized and their inhibitory activity against the HIV-1 protease was tested. Curcumin analogues containing boron enhanced the inhibitory activity. At least of the the synthesized compounds irreversibly inhibits the HIV-1 protease.

Sui, Z.; Li, J.; Craik, C.S.; Ortiz de Montellano, P.R. [Univ. of California, San Francisco, CA (United States)

1993-12-31

385

Emulating Multivariate Output with Derivative Information  

E-print Network

Emulating Multivariate Output with Derivative Information Gemma Stephenson, James Gattiker with a computationally expensive model. Hence an emulator, which is a statistical approximator to the simulator, can model and the emulator is built based on data collected from running the simulator at a specified, small

Oakley, Jeremy

386

Cellulose Derivatives for Water Repellent Properties  

Technology Transfer Automated Retrieval System (TEKTRAN)

In this poster presentation, we will discuss the synthesis and structural characterizations of nitro-benzyl cellulose (1), amino-benzyl cellulose (2) and pentafluoro –benzyl cellulose (3). All cellulose derivatives are synthesized by etherification process in lithium chloride/N,N-dimethylacetamide h...

387

DAMTP 9269 Grassmann Mechanics, Multivector Derivatives and  

E-print Network

DAMTP 92­69 Grassmann Mechanics, Multivector Derivatives and Geometric Algebra \\Lambda Chris Doran of incorporating the results of Grassmann calculus within the framework of geometric algebra is presented symmetry groups, can be expressed purely in terms of the real geometric algebras of space and spacetime

Cambridge, University of

388

Deriving Safety Requirements Using Scenarios Karen Allenby  

E-print Network

Deriving Safety Requirements Using Scenarios Karen Allenby University of York Department.kelly@cs.york.ac.uk Abstract Elicitation of requirements for safety critical aero- engine control systems is dependent deviations from that intent. Deriva- tion of these requirements is inextricably linked to the safety

Kelly, Tim

389

Derivatives and the Graphs of Functions Microworld  

NSDL National Science Digital Library

The purpose of this Microworld is to experiment with some of the general applications of the derivative to the study of the behavior of functions. This includes their critical behavior, their local extrema, regions of monotonicity (increasing or decreasing), and their inflection points.

White, James

2004-11-01

390

Kipukasins: Nucleoside derivatives from Aspergillus versicolor.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Seven new aroyl uridine derivatives (kipukasins A-G; 1-7) were isolated from solid-substrate fermentation cultures of two different Hawaiian isolates of Aspergillus versicolor. The structures of compounds 1-7 were determined by analysis of NMR and MS data. The nucleoside portion of lead compound 1...

391

High speed point derivative microseismic detector  

DOEpatents

A high speed microseismic event detector constructed in accordance with the present invention uses a point derivative comb to quickly and accurately detect microseismic events. Compressional and shear waves impinging upon microseismic receiver stations disposed to collect waves are converted into digital data and analyzed using a point derivative comb including assurance of quiet periods prior to declaration of microseismic events. If a sufficient number of quiet periods have passed, the square of a two point derivative of the incoming digital signal is compared to a trip level threshold exceeding the determined noise level to declare a valid trial event. The squaring of the derivative emphasizes the differences between noise and signal, and the valid event is preferably declared when the trip threshold has been exceeded over a temporal comb width to realize a comb over a given time period. Once a trial event has been declared, the event is verified through a spatial comb, which applies the temporal event comb to additional stations. The detector according to the present invention quickly and accurately detects initial compressional waves indicative of a microseismic event which typically exceed the ambient cultural noise level by a small amount, and distinguishes the waves from subsequent larger amplitude shear waves.

Uhl, James Eugene (Albuquerque, NM); Warpinski, Norman Raymond (Albuquerque, NM); Whetten, Ernest Blayne (Albuquerque, NM)

1998-01-01

392

High speed point derivative microseismic detector  

DOEpatents

A high speed microseismic event detector constructed in accordance with the present invention uses a point derivative comb to quickly and accurately detect microseismic events. Compressional and shear waves impinging upon microseismic receiver stations disposed to collect waves are converted into digital data and analyzed using a point derivative comb including assurance of quiet periods prior to declaration of microseismic events. If a sufficient number of quiet periods have passed, the square of a two point derivative of the incoming digital signal is compared to a trip level threshold exceeding the determined noise level to declare a valid trial event. The squaring of the derivative emphasizes the differences between noise and signal, and the valid event is preferably declared when the trip threshold has been exceeded over a temporal comb width to realize a comb over a given time period. Once a trial event has been declared, the event is verified through a spatial comb, which applies the temporal event comb to additional stations. The detector according to the present invention quickly and accurately detects initial compressional waves indicative of a microseismic event which typically exceed the ambient cultural noise level by a small amount, and distinguishes the waves from subsequent larger amplitude shear waves. 9 figs.

Uhl, J.E.; Warpinski, N.R.; Whetten, E.B.

1998-06-30

393

78 FR 76787 - Position Limits for Derivatives  

Federal Register 2010, 2011, 2012, 2013, 2014

...FUTURES TRADING COMMISSION 17 CFR Parts 1, 15, 17, 19, 32, 37, 38, 140 and 150 RIN 3038-AD99 Position Limits for Derivatives Correction In proposed rule document 2013-27200 appearing on pages 75679 through 75842 in the issue of Thursday,...

2013-12-19

394

Enhancing Knowledge Mapping Using Automatically Derived Concepts  

E-print Network

to obtain a cor- rectly spelled word. Compound contraction. The orthography of new, domain specific compound.g. "domain name", whereas Dutch and German contract constituent words "domainname". Compounds are easy all possible word orders of compound terms in the ontol- ogy and derive a pattern by inserting a near

Anjewierden, Anjo

395

Geometric Derivation of Radial Acceleration Magnitude.  

ERIC Educational Resources Information Center

Standard treatments of uniform circular motion generally employ a combination of geometric and kinematic arguments to obtain the magnitude of radial acceleration. Presents a novel approach to the geometric portion of the derivation that uses the property that vectors can be translated parallel to themselves. (JRH)

Kraft, David W.; Motz, Lloyd

1995-01-01

396

Deriving a Pedagogy of Educational Foundations  

ERIC Educational Resources Information Center

This sixth and last paper in the series describes four elements believed to be crucial to a high quality pedagogy for educational foundations. These four elements are derived from a close reading of the previous papers. The work of Osguthorpe, Sanger, Haniford, and Mucher, four of the authors in this series, is cited as both a source for these…

Fenstermacher, Gary D.

2007-01-01

397

Derived Transformation of Children's Pregambling Game Playing  

ERIC Educational Resources Information Center

Contemporary behavior-analytic perspectives on gambling emphasize the impact of verbal relations, or derived relational responding and the transformation of stimulus functions, on the initiation and maintenance of gambling. Approached in this way, it is possible to undertake experimental analysis of the role of verbal/mediational variables in…

Dymond, Simon; Bateman, Helena; Dixon, Mark R.

2010-01-01

398

Leading Edge Democracy Derived? New Trajectories  

E-print Network

Leading Edge Commentary Democracy Derived? New Trajectories in Pluripotent Stem Cell Research of stem cell research? Here, coauthorship networks of stem cell research articles and analysis of cell lines used in stem cell research indicate that hiPSCs are not replacing human embryonic stem cells

399

Four new hemiterpenoid derivatives from Taxillus chinensis.  

PubMed

Four new hemiterpenoid derivatives, taxilluside A-D (1-4), were isolated from the branches and leaves of Taxillus chinensis (DC.) Danser. Their structures were determined on the basis of spectroscopic analysis. Of these compounds, compounds 3 and 4 showed inhibition activity on Calcium concentration in myocardial cells evaluated by measuring the changes of fluorescence signal using Laser scanning confocal microscope. PMID:23376411

Ding, Bo; Dai, Yi; Hou, Yun-Long; Wu, Xiao-Meng; Chen, Xue; Yao, Xin-Sheng

2013-04-01

400

Radon-Nikodym Derivatives of Gaussian Measures  

Microsoft Academic Search

We give simple necessary and sufficient conditions on the mean and covariance for a Gaussian measure to be equivalent to Wiener measure. This was formerly an unsolved problem [26]. An unsolved problem is to obtain the Radom-Nikodym derivative $d\\\\mu\\/d\\\

L. A. Shepp

1966-01-01

401

Singlet exciton fission in a hexacene derivative.  

PubMed

Hexacene, an acene with six benzene rings, is notable for its exceptionally small triplet energy, around one third of the singlet energy. Herein, singlet fission, i.e., conversion of a singlet exciton into two triplets, is demonstrated in a thin film of hexacene derivative, employing both transient absorption spectroscopy and magnetic field effects on photocurrent. PMID:23293054

Lee, Jiye; Bruzek, Matthew J; Thompson, Nicholas J; Sfeir, Matthew Y; Anthony, John E; Baldo, Marc A

2013-03-13

402

New sulphide derivative from Ferula rutabensis  

Microsoft Academic Search

Reinvestigation of CH2Cl2 extract of roots and rhizomes of Ferula rutabensis led to the isolation of a new trisulphide (1) and phthalic acid derivative (2). Their characterisation was based on their spectral data, including MS, 1D- and 2D-NMR.

Essam Abdel-Sattar; Sahar El-Mekkawy

2009-01-01

403

Sol-Gel Derived Hafnia Coatings  

NASA Technical Reports Server (NTRS)

Sol-gel derived hafnia coatings are being developed to provide an oxidation protection layer on ultra-high temperature ceramics for potential use in turbine engines (ultra-efficient engine technology being developed by NASA). Coatings using hafnia sol hafnia filler particles will be discussed along with sol synthesis and characterization.

Feldman, Jay D.; Stackpoole, Mairead; Blum, Yigal; Sacks, Michael; Ellerby, Don; Johnson, Sylvia M.; Venkatapathy, Ethiras (Technical Monitor)

2002-01-01

404

Communication The monitoring of bovine pregnancies derived  

E-print Network

/ embryo transfer / in vitro fertilization / nuclear transfer Reprod. Nutr. Dev. 42 (2002) 613­624 613Communication The monitoring of bovine pregnancies derived from transfer of in vitro produced are associated with bovine pregnancies obtained from in vitro produced embryos. This thus requires for a more

Paris-Sud XI, Université de

405

Biofuels and bio-products derived from  

E-print Network

NEED Biofuels and bio- products derived from lignocellulosic biomass (plant materials) are part improve the energy and carbon efficiencies of biofuels production from a barrel of biomass using chemical and thermal catalytic mechanisms. The Center for Direct Catalytic Conversion of Biomass to Biofuels IMPACT

Ginzel, Matthew

406

Alternative Derivations for the Poisson Integral Formula  

ERIC Educational Resources Information Center

Poisson integral formula is revisited. The kernel in the Poisson integral formula can be derived in a series form through the direct BEM free of the concept of image point by using the null-field integral equation in conjunction with the degenerate kernels. The degenerate kernels for the closed-form Green's function and the series form of Poisson…

Chen, J. T.; Wu, C. S.

2006-01-01

407

On the logarithm of the derivative operator  

E-print Network

We study the properties of the logarithm of the derivative operator and show that its action on a constant is not zero, but yields the sum of the logarithmic function and the Euler-Mascheroni constant. We discuss more general aspects concerning the logarithm of an operator for the study of the properties of the Bessel functions.

Babusci, D

2011-01-01

408

On the logarithm of the derivative operator  

E-print Network

We study the properties of the logarithm of the derivative operator and show that its action on a constant is not zero, but yields the sum of the logarithmic function and the Euler-Mascheroni constant. We discuss more general aspects concerning the logarithm of an operator for the study of the properties of the Bessel functions.

D. Babusci; G. Dattoli

2011-05-30

409

ERRATUM: Frechet derivatives in inverse obstacle scattering  

Microsoft Academic Search

There is an error in theorem 2.1 of this paper, which shows a representation of the Frchet derivative with respect to the boundary of the far field operator from scattering by obstacles with Robin boundary conditions. The boundary condition in equation (2.4) has to be replaced by where H denotes the mean curvature of the boundary. The error occurs in

Frank Hettlich

1998-01-01

410

Root coverage with enamel matrix derivatives.  

PubMed

Different root coverage procedures have been used to treat cases of gingival recession defects involving single or multiple exposed root surfaces. A therapeutic advantage may be gained if periodontal regeneration is obtained in addition to coverage of the root with gingiva. This article describes the treatment of gingival recession by combining a surgical technique with an enamel matrix derivative. PMID:12365135

Chen, Leon; Cha, Jennifer; Guiha, Rami; Bouwsma, Otis J

2002-09-01

411

Higher and derived stacks: a global overview  

Microsoft Academic Search

These are expended notes of my talk at the summer institute in algebraic geometry (Seattle, July-August 2005), whose main purpose is to present a global overview on the theory of higher and derived stacks. This text is far from being exhaustive but is intended to cover a rather large part of the subject, starting from the motivations and the foundational

Bertrand Toen

2006-01-01

412

Two-point derivative dispersion relations  

NASA Astrophysics Data System (ADS)

A new derivation is given for the representation, under certain conditions, of the integral dispersion relations of scattering theory through local forms. The resulting expressions have been obtained through an independent procedure to construct the real part and consist of new mathematical structures of double infinite summations of derivatives. In this new form the derivatives are calculated at the generic value of the energy E and separately at the reference point E = m that is the lower limit of the integration. This new form may be more interesting in certain circumstances and directly shows the origin of the difficulties in convergence that were present in the old truncated forms called standard-derivative dispersion relations (DDR). For all cases in which the reductions of the double to single sums were obtained in our previous work, leading to explicit demonstration of convergence, these new expressions are seen to be identical to the previous ones. We present, as a glossary, the most simplified explicit results for the DDR's in the cases of imaginary amplitudes of forms (E/m)?[ln (E/m)]n that cover the cases of practical interest in particle physics phenomenology at high energies. We explicitly study the expressions for the cases with ? negative odd integers, that require identification of cancelation of singularities, and provide the corresponding final results.

Ferreira, Erasmo; Sesma, Javier

2013-03-01

413

Synthesis of hydroxy derivatives of limonene  

NASA Astrophysics Data System (ADS)

Synthetic routes to mono-, di- and trihydroxy derivatives of limonene are presented. Emphasis is given to the problems of regio- and stereoselectivity of transformations. Data on the isolation from natural sources and on the biological activities of the title compounds are given. The bibliography includes 107 references.

Ardashov, O. V.; Volcho, K. P.; Salakhutdinov, N. F.

2014-04-01

414

Study on resist performance of chemically amplified molecular resist based on noria derivative and calixarene derivative  

NASA Astrophysics Data System (ADS)

Novel resist materials are required for lithographic processing with ionization radiation such as extreme ultraviolet (EUV) and electron beam (EB) exposure tool. In this study, we developed positive-tone chemically amplified molecular resists based on noria derivatives and calixarene derivatives and evaluated the lithographic performance using EUV and EB. We make clear that a small change in modification of noria resists can cause a significant change of sensitivity. Especially, it is useful for the improvement of resist sensitivities to use protecting groups such as 2-acetyloxy-2-methyladamantyl ester (AD) groups and ethoxy groups. Also, novel calixarene derivative such as pillar[5]arene protected by AD showed a semi-isolated pattern with the line width of 40 nm (pitch: 100nm). Noria derivatives and calixarene derivative resists were promising candidates because of high sensitivity, high resolution and etch durability similar to conventional resist such as ZEP 520A and UVIII.

Yamamoto, Hiroki; Kudo, Hiroto; Kozawa, Takahiro

2014-03-01

415

Familial Follicular Cell-Derived Thyroid Carcinoma  

PubMed Central

Follicular cell-derived well-differentiated thyroid cancer, papillary (PTC) and follicular thyroid carcinomas comprise 95% of all thyroid malignancies. Familial follicular cell-derived well-differentiated thyroid cancers contribute 5% of cases. Such familial follicular cell-derived carcinomas or non-medullary thyroid carcinomas (NMTC) are divided into two clinical–pathological groups. The syndromic-associated group is composed of predominately non-thyroidal tumors and includes Pendred syndrome, Warner syndrome, Carney complex (CNC) type 1, PTEN-hamartoma tumor syndrome (PHTS; Cowden disease), and familial adenomatous polyposis (FAP)/Gardner syndrome. Other conditions with less established links to the development of follicular cell-derived tumors include ataxia–telangiectasia syndrome, McCune Albright syndrome, and Peutz–Jeghers syndrome. The final group encompasses syndromes typified by NMTC, as well as pure familial (f) PTC with or without oxyphilia, fPTC with multinodular goiter, and fPTC with papillary renal cell carcinoma. This heterogeneous group of diseases does not have the established genotype–phenotype correlations known as in the familial C-cell-derived tumors or medullary thyroid carcinomas (MTC). Clinicians should have the knowledge to identify the likelihood of a patient presenting with thyroid cancer having an additional underlying familial syndrome stemming from characteristics by examining morphological findings that would alert pathologists to recommend that patients undergo molecular genetic evaluation. This review discusses the clinical and pathological findings of patients with familial PTC, such as FAP, CNC, Werner syndrome, and Pendred syndrome, and the heterogeneous group of familial PTC. PMID:22654876

Son, Eun Ju; Nosé, Vânia

2012-01-01

416

Neuroprotective Properties of Chitosan and Its Derivatives  

PubMed Central

Neuronal cells are extremely vulnerable and have a limited capacity for self-repair in response to injury. For those reasons, there is obvious interest in limiting neuronal damage. Mechanisms and strategies used in order to protect against neuronal injury, apoptosis, dysfunction, and degeneration in the central nervous system are recognized as neuroprotection. Neuroprotection could be achieved through several classes of natural and synthetic neuroprotective agents. However, considering the side effects of synthetic neuroprotective agents, the search for natural neuroprotective agents has received great attention. Recently, an increasing number of studies have identified neuroprotective properties of chitosan and its derivatives; however, there are some significant challenges that must be overcome for the success of this approach. Hence, the objective of this review is to discuss neuroprotective properties of chitosan and its derivatives. PMID:20714426

Pangestuti, Ratih; Kim, Se-Kwon

2010-01-01

417

Antitumor Activity of Bis-Indole Derivatives  

PubMed Central

This paper reports the synthesis of compounds formed by two indole systems separated by a heterocycle (pyridine or piperazine). As a primary screening, the new compounds were submitted to the National Cancer Institute for evaluation of antitumor activity in the human cell line screen. The pyridine derivatives were far more active than the piperazine derivatives. For the study of the mechanism of action, the most active compounds were subjected to COMPARE analysis and to further biological tests including proteasome inhibition and inhibition of plasma membrane electron transport. The compound bearing the 5-methoxy-2-indolinone moiety was subjected to the first in vivo experiment (hollow fiber assay) and was active. It was therefore selected for the second in vivo experiment (human tumor xenograft in mice). In conclusion we demonstrated that this approach was successful since some of the compounds described are much more active than the numerous, so far prepared and tested 3-indolylmethylene-2-indolinones. PMID:18598018

Andreani, Aldo; Burnelli, Silvia; Granaiola, Massimiliano; Leoni, Alberto; Locatelli, Alessandra; Morigi, Rita; Rambaldi, Mirella; Varoli, Lucilla; Landi, Laura; Prata, Cecilia; Berridge, Michael V.; Grasso, Carole; Fiebig, Heinz-Herbert; Kelter, Gerhard; Burger, Angelika M.; Kunkel, Mark W.

2009-01-01

418

Mechanical properties of titania-derived nanoribbons  

NASA Astrophysics Data System (ADS)

The mechanical properties of TiO2-derived nanoribbons were investigated by using a three-point bending method. Thin nanoribbons (cross-section dimension ~30 nm) have an average Young's modulus of 260 ± 55 GPa. For thicker nanoribbons, which are composed of several thinner nanostrips, the bending modulus rapidly decreases with increasing cross-section. In analogy with carbon nanotube ropes we argue that shear deformations become important and the shear modulus is G = 0.07-0.4 GPa. The present results together with our previous work suggest that TiO2-derived nanoribbons and nanotubes may undertake a dual function in polymer composites: they could reinforce the polymer matrix while at the same time they could provide a large active surface area.

Humar, M.; Arcon, D.; Umek, P.; Skarabot, M.; Musevic, I.; Bregar, G.

2006-08-01

419

Bacterial degradation of chlorophenols and their derivatives  

PubMed Central

Chlorophenols (CPs) and their derivatives are persistent environmental pollutants which are used in the manufacture of dyes, drugs, pesticides and other industrial products. CPs, which include monochlorophenols, polychlorophenols, chloronitrophenols, chloroaminophenols and chloromethylphenols, are highly toxic to living beings due to their carcinogenic, mutagenic and cytotoxic properties. Several physico-chemical and biological methods have been used for removal of CPs from the environment. Bacterial degradation has been considered a cost-effective and eco-friendly method of removing CPs from the environment. Several bacteria that use CPs as their sole carbon and energy sources have been isolated and characterized. Additionally, the metabolic pathways for degradation of CPs have been studied in bacteria and the genes and enzymes involved in the degradation of various CPs have been identified and characterized. This review describes the biochemical and genetic basis of the degradation of CPs and their derivatives. PMID:24589366

2014-01-01

420

Fatty acid-derived signals in plants.  

PubMed

Plants synthesize many fatty acid derivatives, several of which play important regulatory roles. Jasmonates are the best characterized examples. Jasmonate-insensitive mutants and mutants with a constitutive jasmonate response have given us new insights into jasmonate signalling. The jasmonate biosynthesis mutant opr3 allowed the dissection of cyclopentanone and cyclopentenone signalling, thus defining specific roles for these molecules. Jasmonate signalling is a complex network of individual signals and recent findings on specific activities of methyl jasmonate and (Z)-jasmone add to this picture. In addition, there are keto, hydroxy and hydroperoxy fatty acids that might be involved in cell death and the expression of stress-related genes. Finally, there are bruchins and volicitin, signal molecules from insects that are perceived by plants in the picomole to femtomole range. They highlight the importance of fatty acid-derived molecules in interspecies communication and in plant defence. PMID:11992827

Weber, Hans

2002-05-01

421

Inequalities for a polynomial and its derivative  

NASA Astrophysics Data System (ADS)

Let , 1[less-than-or-equals, slant][mu][less-than-or-equals, slant]n, be a polynomial of degree n such that p(z)[not equal to]0 in z0, then for 0derivative, Math. Inequal. Appl. 2 (2) (1999) 203-205] proved Equality holds for the polynomial where n is a multiple of [mu]E In this paper, we obtain an improvement of the above inequality by involving some of the coefficients. As an application of our result, we further improve upon a result recently proved by Aziz and Shah [A. Aziz, W.M. Shah, Inequalities for a polynomial and its derivative, Math. Inequal. Appl. 7 (3) (2004) 379-391].

Chanam, Barchand; Dewan, K. K.

2007-12-01

422

Tooth-derived bone graft material  

PubMed Central

With successful extraction of growth factors and bone morphogenic proteins (BMPs) from mammalian teeth, many researchers have supported development of a bone substitute using tooth-derived substances. Some studies have also expanded the potential use of teeth as a carrier for growth factors and stem cells. A broad overview of the published findings with regard to tooth-derived regenerative tissue engineering technique is outlined. Considering more than 100 published papers, our team has developed the protocols and techniques for processing of bone graft material using extracted teeth. Based on current studies and studies that will be needed in the future, we can anticipate development of scaffolds, homogenous and xenogenous tooth bone grafts, and dental restorative materials using extracted teeth. PMID:24471027

Kim, Young-Kyun; Lee, Junho; Kim, Kyung-Wook; Murata, Masaru; Akazawa, Toshiyuki; Mitsugi, Masaharu

2013-01-01

423

Dimeric cinnamoylamide derivatives as inhibitors of melanogenesis.  

PubMed

Dimeric cinnamoylamide derivatives were synthetized and tested as inhibitors of tyrosinase activity and melanin formation. The most active dimeric cinnamoylamide derivatives was dimeric compound of p-coumaric acid (compound 1) that inhibited tyrosinase activity more efficiently than p-coumaric acid. It also inhibited melanin production by B16 melanoma cell line and normal human melanocytes more efficiently than kojic acid. We next investigated the potential mutagenic and skin sensitization effect of compound 1. Compound 1 was found to induce no mutagenic activity, no irritation and no delayed contact hypersensitivity at the maximum concentration of 10%. In vitro percutaneous absorption studies exhibited that compound 1 could diffuse across the skin till its site of action. All these results lead us to propose that compound 1 may be a safe and effective candidate for treating skin hyperpigmentation related disorders. PMID:21372395

Criton, Marc; Le Mellay-Hamon, Véronique

2011-01-01

424

Scalar wormholes with nonminimal derivative coupling  

NASA Astrophysics Data System (ADS)

We consider static spherically symmetric wormhole configurations in a gravitational theory of a scalar field with a potential V(?) and nonminimal derivative coupling to the curvature described by the term (?g?? + ?G??)?, ??, ? in the action. We show that the flare-out conditions providing the geometry of a wormhole throat could be fulfilled both if ? = -1 (phantom scalar) and ? = +1 (ordinary scalar). Supposing additionally a traversability, we construct numerical solutions describing traversable wormholes in the model with arbitrary ?, ? = -1 and V(?) = 0 (no potential). The traversability assumes that the wormhole possesses two asymptotically flat regions with corresponding Schwarzschild masses. We find that asymptotical masses of a wormhole with nonminimal derivative coupling could be positive and/or negative depending on ?. In particular, both masses are positive only provided ? < ?1 ? 0; otherwise, one or both wormhole masses are negative. In conclusion, we give qualitative arguments that a wormhole configuration with positive masses could be stable.

Sushkov, Sergey V.; Korolev, Roman

2012-04-01

425

Synthesis and pharmacological activity of diterpenylnaphthoquinone derivatives.  

PubMed

New diterpenylquinones, combining a diterpene diacid and a naphthoquinone, were prepared from junicedric acid and lapachol. The new derivatives were assessed as gastroprotective agents by the HCl-EtOH-induced gastric lesions model in mice as well as for basal cytotoxicity on the following human cell lines: Normal lung fibroblasts (MRC-5), gastric epithelial adenocarcinoma (AGS), and hepatocellular carcinoma (Hep G2). Several of the new compounds were significantly active as antiulcer agents and showed selective cytotoxicity against AGS cells. PMID:21996716

Pertino, Mariano Walter; Theoduloz, Cristina; Palenzuela, Jose Antonio; Afonso, Maria del Mar; Yesilada, Erdem; Monsalve, Francisco; González, Paulo; Droguett, Daniel; Schmeda-Hirschmann, Guillermo

2011-01-01

426

Chemically Derived, Ultrasmooth Graphene Nanoribbon Semiconductors  

Microsoft Academic Search

We developed a chemical route to produce graphene nanoribbons (GNR) with width below 10 nanometers, as well as single ribbons with varying widths along their lengths or containing lattice-defined graphene junctions for potential molecular electronics. The GNRs were solution-phase derived, stably suspended in solvents with noncovalent polymer functionalization, and exhibited ultrasmooth edges with possibly well-defined zigzag or armchair-edge structures. Electrical

Xiaolin Li; Xinran Wang; Li Zhang; Sangwon Lee; Hongjie Dai

2008-01-01

427

Canonical structure of higher derivative theories  

NASA Astrophysics Data System (ADS)

The canonical structure of theories whose Lagrangian contains higher powers of time derivatives is often obscured by the nonlinear relationship between the velocities and momenta. We use the Dirac formalism and define a generalized Legendre transform to overcome some of the difficulties associated with inverting the relation between velocities and momenta. We are then able to define a standard single valued symplectic structure on phase space and a compatible single valued Hamiltonian. We demonstrate the application of our formalism in several examples.

Avraham, Eran; Brustein, Ram

2014-07-01

428

Eosinophil Secretion of Granule-Derived Cytokines  

PubMed Central

Eosinophils are tissue-dwelling leukocytes, present in the thymus, and gastrointestinal and genitourinary tracts of healthy individuals at baseline, and recruited, often in large numbers, to allergic inflammatory foci and sites of active tissue repair. The biological significance of eosinophils is vast and varied. In health, eosinophils support uterine and mammary gland development, and maintain bone marrow plasma cells and adipose tissue alternatively activated macrophages, while in response to tissue insult eosinophils function as inflammatory effector cells, and, in the wake of an inflammatory response, promote tissue regeneration, and wound healing. One common mechanism driving many of the diverse eosinophil functions is the regulated and differential secretion of a vast array of eosinophil-derived cytokines. Eosinophils are distinguished from most other leukocytes in that many, if not all, of the over three dozen eosinophil-derived cytokines are pre-synthesized and stored within intracellular granules, poised for very rapid, stimulus-induced secretion. Eosinophils engaged in cytokine secretion in situ utilize distinct pathways of cytokine release that include classical exocytosis, whereby granules themselves fuse with the plasma membrane and release their entire contents extracellularly; piecemeal degranulation, whereby granule-derived cytokines are selectively mobilized into vesicles that emerge from granules, traverse the cytoplasm and fuse with the plasma membrane to release discrete packets of cytokines; and eosinophil cytolysis, whereby intact granules are extruded from eosinophils, and deposited within tissues. In this latter scenario, extracellular granules can themselves function as stimulus-responsive secretory-competent organelles within the tissue. Here, we review the distinctive processes of differential secretion of eosinophil granule-derived cytokines. PMID:25386174

Spencer, Lisa A.; Bonjour, Kennedy; Melo, Rossana C. N.; Weller, Peter F.

2014-01-01

429

Synthesis of Silicon Derivatives with Ruthenium Catalysts  

Microsoft Academic Search

Methods for synthesis of saturated and unsaturated organosilicon compounds as well as other silicon derivatives based on ruthenium-catalyzed reactions have been reviewed. All the catalytic processes discussed lead to formation of either novel carbon–silicon bonds or novel carbon–carbon bonds affected by a substituted silyl group at carbon. Saturated organosilicon products can be prepared via hydrosilylation of alkenes and activation of

Bogdan Marciniec; Cezary Pietraszuk

430

Synthesis and cytotoxicity study of alkannin derivatives  

Microsoft Academic Search

Alkannin derivatives (3–19) were prepared through the reaction of ?,?-dimethylacrylalkannin (1), the most abundant isohexenylnaphthazarin isolated from the roots of Arnebia euchroma, with different types of nucleophiles such as amines and thiols in the absence or presence of a reducing agent. The cytotoxicities of 1–8, 10–14 and 19 against four human carcinoma cell line (GLC-82, CNE2, Bel-7402, K-562) were found

Zhi-Shu Huang; Hai-Qiang Wu; Zhi-Fang Duan; Bing-Fen Xie; Zong-Chao Liu; Gong-Kan Feng; Lian-Quan Gu; Albert S. C. Chan; Yue-Ming Li

2004-01-01

431

Blue photoluminescence from chemically derived graphene oxide  

Microsoft Academic Search

Fluorescent organic compounds are of significant importance to the development of low-cost opto-electronic devices. Blue fluorescence from aromatic or olefinic molecules and their derivatives is particularly important for display and lighting applications. Thin film deposition of low-molecular-weight fluorescent organic compounds typically requires costly vacuum evaporation systems. On the other hand, solution-processable polymeric counterparts generally luminesce at longer wavelengths due to

Goki Eda; Yun-Yue Lin; Cecilia Mattevi; Hisato Yamaguchi; Hsin-An Chen; I-Sheng Chen; Chun-Wei Chen; Manish Chhowalla

2009-01-01

432

Acetylene-Terminated Aspartimides And Derived Resins  

NASA Technical Reports Server (NTRS)

New polymers and derived blends exhibit improved processability and properties. New toughened epoxies exhibit excellent properties, but use temperatures limited. Bismaleimide resins are some base materials formulated to develop materials having moderate use temperatures. Work conducted on use of acetylenic (ethynyl) group to cross-link and extend chains of oligomers and polymers to obtain materials to perform at higher temperatures. Extended to include acetylene-terminated aspartimides (ATA's).

Hergenrother, Paul M.; Connell, John W.; Havens, Stephen J.

1989-01-01

433

Triamine chelants, their derivatives, complexes and conjugates  

DOEpatents

A group of functionalized triamine chelants and their derivatives that form complexes with radioactive metal ions are disclosed. The complexes can be covalently attached to a protein or an antibody or antibody fragment and used for therapeutic and/or diagnostic purposes. The chelants are of the formula: ##STR1## wherein n, m, R, R.sup.1, R.sup.2 and L are defined in the specification.

Troutner, David E. (Phoenixville, PA); John, Christy S. (Gaithersburg, MD); Pillai, Maroor R. A. (Vashi, IN)

1995-01-01

434

Triamine chelants, their derivatives, complexes and conjugates  

DOEpatents

A group of functionalized triamine chelants and their derivatives that form complexes with radioactive metal ions are disclosed. The complexes can be covalently attached to a protein or an antibody or antibody fragment and used for therapeutic and/or diagnostic purposes. The chelants are of the formula, as shown in the accompanying diagrams, wherein n, m, R, R{sup 1}, R{sup 2} and L are defined in the specification.

Troutner, D.E.; John, C.S.; Pillai, M.R.A.

1995-03-07

435

The Fréchet Derivatives of Electromagnetic Induction  

Microsoft Academic Search

netic induction are examined in detail. The response functions for both modes are shown to be Fr6chet differentiable in an L 2 norm for general conductivity structures and arbitrary source frequency-wavenumber morphology. Perturbation forms of the modal Green functions are derived and used to examine the Fr6chet kernels for a seafloor controlled source and a Kelvin wave model. In both

Alan D. Chave

1984-01-01

436

Joint moments of derivatives of characteristic polynomials  

E-print Network

We investigate the joint moments of the 2k-th power of the characteristic polynomial of random unitary matrices with the 2h-th power of the derivative of this same polynomial. We prove that for a fixed h, the moments are given by rational functions of k, up to a well-known factor that already arises when h=0. We fully describe the denominator in those rational functions (this had already been done by Hughes experimentally), and define the numerators through various formulas, mostly sums over partitions. We also use this to formulate conjectures on joint moments of the zeta function and its derivatives, or even the same questions for the Hardy function, if we use a ``real'' version of characteristic polynomials. Our methods should easily be applicable to other similar problems, for instance with higher derivatives of characteristic polynomials. NOTE: More data is available on the author's website or attached to the LaTeX source of this arXiv submission.

Paul-Olivier Dehaye

2007-03-15

437

Derivation of naïve human embryonic stem cells  

PubMed Central

The naïve pluripotent state has been shown in mice to lead to broad and more robust developmental potential relative to primed mouse epiblast cells. The human naïve ES cell state has eluded derivation without the use of transgenes, and forced expression of OCT4, KLF4, and KLF2 allows maintenance of human cells in a naïve state [Hanna J, et al. (2010) Proc Natl Acad Sci USA 107(20):9222–9227]. We describe two routes to generate nontransgenic naïve human ES cells (hESCs). The first is by reverse toggling of preexisting primed hESC lines by preculture in the histone deacetylase inhibitors butyrate and suberoylanilide hydroxamic acid, followed by culture in MEK/ERK and GSK3 inhibitors (2i) with FGF2. The second route is by direct derivation from a human embryo in 2i with FGF2. We show that human naïve cells meet mouse criteria for the naïve state by growth characteristics, antibody labeling profile, gene expression, X-inactivation profile, mitochondrial morphology, microRNA profile and development in the context of teratomas. hESCs can exist in a naïve state without the need for transgenes. Direct derivation is an elusive, but attainable, process, leading to cells at the earliest stage of in vitro pluripotency described for humans. Reverse toggling of primed cells to naïve is efficient and reproducible. PMID:24623855

Ware, Carol B.; Nelson, Angelique M.; Mecham, Brigham; Hesson, Jennifer; Zhou, Wenyu; Jonlin, Erica C.; Jimenez-Caliani, Antonio J.; Deng, Xinxian; Cavanaugh, Christopher; Cook, Savannah; Tesar, Paul J.; Okada, Jeffrey; Margaretha, Lilyana; Sperber, Henrik; Choi, Michael; Blau, C. Anthony; Treuting, Piper M.; Hawkins, R. David; Cirulli, Vincenzo; Ruohola-Baker, Hannele

2014-01-01

438

Neutrophil-Derived Cytokines: Facts Beyond Expression  

PubMed Central

Polymorphonuclear neutrophils, besides their involvement in primary defense against infections – mainly through phagocytosis, generation of toxic molecules, release of enzymes, and formation of extracellular traps – are also becoming increasingly important for their contribution to the fine regulation in development of inflammatory and immune responses. These latter functions of neutrophils occur, in part, via their de novo production and release of a large variety of cytokines, including chemotactic cytokines (chemokines). Accordingly, the improvement in technologies for molecular and functional cell analysis, along with concomitant advances in cell purification techniques, have allowed the identification of a continuously growing list of neutrophil-derived cytokines, as well as the characterization of their biological implications in vitro and/or in vivo. This short review summarizes crucial concepts regarding the modalities of expression, release, and regulation of neutrophil-derived cytokines. It also highlights examples illustrating the potential implications of neutrophil-derived cytokines according to recent observations made in humans and/or in experimental animal models. PMID:25374568

Tecchio, Cristina; Micheletti, Alessandra; Cassatella, Marco A.

2014-01-01

439

Derivation of naive human embryonic stem cells.  

PubMed

The naïve pluripotent state has been shown in mice to lead to broad and more robust developmental potential relative to primed mouse epiblast cells. The human naïve ES cell state has eluded derivation without the use of transgenes, and forced expression of OCT4, KLF4, and KLF2 allows maintenance of human cells in a naïve state [Hanna J, et al. (2010) Proc Natl Acad Sci USA 107(20):9222-9227]. We describe two routes to generate nontransgenic naïve human ES cells (hESCs). The first is by reverse toggling of preexisting primed hESC lines by preculture in the histone deacetylase inhibitors butyrate and suberoylanilide hydroxamic acid, followed by culture in MEK/ERK and GSK3 inhibitors (2i) with FGF2. The second route is by direct derivation from a human embryo in 2i with FGF2. We show that human naïve cells meet mouse criteria for the naïve state by growth characteristics, antibody labeling profile, gene expression, X-inactivation profile, mitochondrial morphology, microRNA profile and development in the context of teratomas. hESCs can exist in a naïve state without the need for transgenes. Direct derivation is an elusive, but attainable, process, leading to cells at the earliest stage of in vitro pluripotency described for humans. Reverse toggling of primed cells to naïve is efficient and reproducible. PMID:24623855

Ware, Carol B; Nelson, Angelique M; Mecham, Brigham; Hesson, Jennifer; Zhou, Wenyu; Jonlin, Erica C; Jimenez-Caliani, Antonio J; Deng, Xinxian; Cavanaugh, Christopher; Cook, Savannah; Tesar, Paul J; Okada, Jeffrey; Margaretha, Lilyana; Sperber, Henrik; Choi, Michael; Blau, C Anthony; Treuting, Piper M; Hawkins, R David; Cirulli, Vincenzo; Ruohola-Baker, Hannele

2014-03-25

440

Affinity of guanosine derivatives for polycytidylate revisited  

NASA Technical Reports Server (NTRS)

Evidence is presented for complexation of guanosine 5'-monophosphate 2-methylimidazolide (2-MeImpG) with polycytidylate (poly(C)) at pH 8.0 and 23 degrees C in the presence of 1.0 M NaCl2 and 0.2 M MgCl2 in water. The association of 2-MeImpG with poly(C) was investigated using UV-vis spectroscopy as well as by monitoring the kinetics of the nucleophilic substitution reaction of the imidazole moiety by amines. The results of both methods are consistent with moderately strong poly(C) 2-MeImpG complexation and the spectrophotometric measurements allowed the construction of a binding isotherm with a concentration of 2-MeImpG equal to 5.55 +/- 0.15 mM at half occupancy. UV spectroscopy was employed to establish the binding of other guanosine derivatives on poly(C). These derivatives are guanosine 5'-monophosphate (5'GMP), guanosine 5'-monophosphate imidazolide (ImpG), and guanosine 5'-monophosphate morpholidate (morpG). Within experimental error these guanosine derivatives exhibit the same affinity for poly(C) as 2-MeImpG.

Kanavarioti, A.; Hurley, T. B.; Baird, E. E.

1995-01-01

441

Two-point derivative dispersion relations  

E-print Network

A new derivation is given for the representation, under certain conditions, of the integral dispersion relations of scattering theory through local forms. The resulting expressions have been obtained through an independent procedure to construct the real part, and consist of new mathematical structures of double infinite summations of derivatives. In this new form the derivatives are calculated at the generic value of the energy $E$ and separately at the reference point $E=m$ that is the lower limit of the integration. This new form may be more interesting in certain circumstances and directly shows the origin of the difficulties in convergence that were present in the old truncated forms called standard-DDR. For all cases in which the reductions of the double to single sums were obtained in our previous work, leading to explicit demonstration of convergence, these new expressions are seen to be identical to the previous ones. We present, as a glossary, the most simplified explicit results for the DDR's in the cases of imaginary amplitudes of forms $(E/m)^\\lambda[\\ln (E/m)]^n$, that cover the cases of practical interest in particle physics phenomenology at high energies. We explicitly study the expressions for the cases with $\\lambda$ negative odd integers, that require identification of cancelation of singularities, and provide the corresponding final results.

Erasmo Ferreira; Javier Sesma

2014-03-24

442

Long-memory volatility in derivative hedging  

NASA Astrophysics Data System (ADS)

The aim of this work is to take into account the effects of long memory in volatility on derivative hedging. This idea is an extension of the work by Fedotov and Tan [Stochastic long memory process in option pricing, Int. J. Theor. Appl. Finance 8 (2005) 381-392] where they incorporate long-memory stochastic volatility in option pricing and derive pricing bands for option values. The starting point is the stochastic Black-Scholes hedging strategy which involves volatility with a long-range dependence. The stochastic hedging strategy is the sum of its deterministic term that is classical Black-Scholes hedging strategy with a constant volatility and a random deviation term which describes the risk arising from the random volatility. Using the fact that stock price and volatility fluctuate on different time scales, we derive an asymptotic equation for this deviation in terms of the Green's function and the fractional Brownian motion. The solution to this equation allows us to find hedging confidence intervals.

Tan, Abby

2006-10-01

443

Hypersensitivity reactions to anthranilic acid derivatives.  

PubMed

Anthranilic acid derivatives are a group of nonsteroidal antiinflammatory drugs that include glafenine and fenamates. We report a woman who had immediate adverse reactions to glafenine and meclofenamate sodium. Skin prick and intradermal tests were performed with solutions of glafenine and meclofenamate in phosphate-buffered saline (PBS) and with the drugs bound to human serum albumin (HSA). Prick and intradermal tests with PBS solutions were negative for both drugs as were prick tests with HSA solutions. Intradermal tests with HSA-glafenine, however, were positive at 20 minutes, and at 6 and 24 hours. Intradermal tests with HSA-meclofenamate elicited a positive response at 6 and 24 hours. These tests were negative when performed in control subjects. A leukocyte histamine release test and a RAST assay were negative for both drugs. The patient was challenged following a double-blind placebo-controlled oral procedure and tolerated therapeutic doses of aspirin, indomethacin, ibuprofen, dipyrone, diclofenac, piroxicam, and acetaminophen. The oral challenge with glafenine and meclofenamate reproduced the reactions (eliciting doses: 50 mg and 15 mg, respectively), and the patient also reacted to 30 mg of mefenamic acid, an anthranilic acid derivative she had never previously received. This is an exceptional case of selective adverse reactions to glafenine and fenamates, anthranilic acid derivatives, in a patient tolerating aspirin and other cyclooxygenase inhibitors. Our study implicates an immunologic mechanism, and the existence of cross-reactivity between the drugs (or some active metabolite generated in vivo). PMID:7903514

Fernandez-Rivas, M; de la Hoz, B; Cuevas, M; Davila, I; Quirce, S; Losada, E

1993-12-01

444

Exosomes Derived from Mesenchymal Stem Cells  

PubMed Central

The functional mechanisms of mesenchymal stem cells (MSCs) have become a research focus in recent years. Accumulating evidence supports the notion that MSCs act in a paracrine manner. Therefore, the biological factors in conditioned medium, including exosomes and soluble factors, derived from MSC cultures are being explored extensively. The results from most investigations show that MSC-conditioned medium or its components mediate some biological functions of MSCs. Several studies have reported that MSC-derived exosomes have functions similar to those of MSCs, such as repairing tissue damage, suppressing inflammatory responses, and modulating the immune system. However, the mechanisms are still not fully understood and the results remain controversial. Compared with cells, exosomes are more stable and reservable, have no risk of aneuploidy, a lower possibility of immune rejection following in vivo allogeneic administration, and may provide an alternative therapy for various diseases. In this review, we summarize the properties and biological functions of MSC-derived exosomes and discuss the related mechanisms. PMID:24608926

Yu, Bo; Zhang, Xiaomin; Li, Xiaorong

2014-01-01

445

Fluid dynamic derivatives: Marine and wind engineering approaches  

Microsoft Academic Search

An alternative formulation, applied in marine and air craft fluid dynamics, of the traditional aerodynamic derivatives model, is presented. The relationship between the derivatives of the two models is derived, from which the exact interdependencies of the derivatives of the traditional model can be found. A forced motion model testing device, termed a planar motion mechanism (PMM), applicable for the

Andreas G. Jensen

1997-01-01

446

Transformation of spatial and perturbation derivatives of travel time  

E-print Network

Transformation of spatial and perturbation derivatives of travel time at a general interface and perturbation parameters. We derive the explicit equations for transforming these travel­time derivatives Hamiltonian function and are applicable to the transformation of travel­time derivatives in both isotropic

Cerveny, Vlastislav

447

Rough Derivatives in Rough Function Model and Their Application  

Microsoft Academic Search

On the theory and application of rough derivatives in rough function model, the notion of generalized rough functions is defined to improve the definition of higher order rough derivatives Pawlak proposed, and analyze the functional features of roughly derived functions and higher order roughly derived functions. The rough extremum definition of discrete functions is given, Fermat theorem and Rolle theorem

Yun Wang; Yanyong Guan; Hongkai Wang

2007-01-01

448

Stem cell-derived neurons functionally integrate in  

E-print Network

Stem cell-derived neurons functionally integrate in living mice Neurons derived from stem cells that, after transplantation into living animals, human stem cell-derived neurons can receive neuronal human embryonic stem cell (hESC)-derived neurons engineered to be specifically activated by light

Fortuna, Miguel A.

449

Hydrogen From Bio-Derived LiquidsHydrogen From BioHydrogen From Bio--Derived LiquidsDerived Liquids Dave King, Yong Wang, PNNL  

E-print Network

production Ethanol is rapidly becoming an infrastructure fuel and is a logical feedstock APR provides H2 product 63.173448 120010.91 140353.17 Fuel ethanol 418.8445 26817.293 29487.8 Steam Molar Flow CoHydrogen From Bio-Derived LiquidsHydrogen From BioHydrogen From Bio--Derived LiquidsDerived Liquids

450

Biologic Rhythms Derived from Siberian Mammoths' Hairs  

PubMed Central

Hair is preserved for millennia in permafrost; it enshrines a record of biologic rhythms and offers a glimpse at chronobiology as it was in extinct animals. Here we compare biologic rhythms gleaned from mammoth's hairs with those of modern human hair. Four mammoths' hairs came from varying locations in Siberia 4600 km, four time zones, apart ranging in age between 18,000 and 20,000 years before present. We used two contemporaneous human hairs for comparison. Power spectra derived from hydrogen isotope ratios along the length of the hairs gave insight into biologic rhythms, which were different in the mammoths depending on location and differed from humans. Hair growth for mammoths was ?31 cms/year and ?16 cms/year for humans. Recurrent annual rhythms of slow and fast growth varying from 3.4 weeks/cycles to 8.7 weeks/cycles for slow periods and 1.2 weeks/cycles to 2.2 weeks/cycles for fast periods were identified in mammoth's hairs. The mineral content of mammoth's hairs was measured by electron microprobe analysis (k-ratios), which showed no differences in sulfur amongst the mammoth hairs but significantly more iron then in human hair. The fractal nature of the data derived from the hairs became evident in Mandelbrot sets derived from hydrogen isotope ratios, mineral content and geographic location. Confocal microscopy and scanning electron microscopy showed varied degrees of preservation of the cuticle largely independent of age but not location of the specimens. X-ray fluorescence microprobe and fluorescence computed micro-tomography analyses allowed evaluation of metal distribution and visualization of hollow tubes in the mammoth's hairs. Seasonal variations in iron and copper content combined with spectral analyses gave insights into variation in food intake of the animals. Biologic rhythms gleaned from power spectral plots obtained by modern methods revealed life style and behavior of extinct mega-fauna. PMID:21747920

Spilde, Mike; Lanzirotti, Antonio; Qualls, Clifford; Phillips, Genevieve; Ali, Abdul-Mehdi; Agenbroad, Larry; Appenzeller, Otto

2011-01-01

451

Nonclassical biological activities of quinolone derivatives.  

PubMed

Quinolones are considered as a big family of multi-faceted drugs; their chemical synthesis is flexible and can be easily adapted to prepare new congeners with rationally devised structures. This is shown by the description of many thousands of derivatives in the literature. Scientists could accurately describe their QSAR, which is essential for effective drug design. This also gave them the chance to discover new and unprecedented activities, which makes quinolones an endless source of hope and enables further development of new clinically useful drugs. Quinolones are among the most common frameworks present in the bioactive molecules that have dominated the market for more than four decades. Since 1962, 4(1H)-quinolone-3-carboxylic acid derivatives are widely used as antibacterial agents. Quinolones have a broad and potent spectrum of activity and are also used as second-line drugs to treat tuberculosis (TB). Recently, quinolones have been reported to display "nonclassical" biological activities, such as antitumor, anti-HIV-1 integrase, anti-HCV-NS3 helicase and -NS5B-polymerase activities. The present review focuses on the structural modifications responsible for the transformation of an antibacterial into an anticancer agent and/or an antiviral agent. Indeed, quinolones' antimicrobial action is distinguishable among antibacterial agents, because they target different type II topoisomerase enzymes. Many derivatives of this family show high activity against bacterial topoisomerases and eukaryotic topoisomerases, and are also toxic to cultured mammalian cells and in vivo tumor models. Moreover, quinolones have shown antiviral activity against HIV and HCV viruses. In this context the quinolones family of drugs seem to link three different biological activities (antibacterial, anticancer, and the antiviral profiles) and the review will also provide an insight into the different mechanisms responsible for these activities among different species. PMID:22365088

Ahmed, Abeer; Daneshtalab, Mohsen

2012-01-01

452

Biologic Rhythms Derived from Siberian Mammoths Hairs  

SciTech Connect

Hair is preserved for millennia in permafrost; it enshrines a record of biologic rhythms and offers a glimpse at chronobiology as it was in extinct animals. Here we compare biologic rhythms gleaned from mammoth's hairs with those of modern human hair. Four mammoths' hairs came from varying locations in Siberia 4600 km, four time zones, apart ranging in age between 18,000 and 20,000 years before present. We used two contemporaneous human hairs for comparison. Power spectra derived from hydrogen isotope ratios along the length of the hairs gave insight into biologic rhythms, which were different in the mammoths depending on location and differed from humans. Hair growth for mammoths was {approx}31 cms/year and {approx}16 cms/year for humans. Recurrent annual rhythms of slow and fast growth varying from 3.4 weeks/cycles to 8.7 weeks/cycles for slow periods and 1.2 weeks/cycles to 2.2 weeks/cycles for fast periods were identified in mammoth's hairs. The mineral content of mammoth's hairs was measured by electron microprobe analysis (k-ratios), which showed no differences in sulfur amongst the mammoth hairs but significantly more iron then in human hair. The fractal nature of the data derived from the hairs became evident in Mandelbrot sets derived from hydrogen isotope ratios, mineral content and geographic location. Confocal microscopy and scanning electron microscopy showed varied degrees of preservation of the cuticle largely independent of age but not location of the specimens. X-ray fluorescence microprobe and fluorescence computed micro-tomography analyses allowed evaluation of metal distribution and visualization of hollow tubes in the mammoth's hairs. Seasonal variations in iron and copper content combined with spectral analyses gave insights into variation in food intake of the animals. Biologic rhythms gleaned from power spectral plots obtained by modern methods revealed life style and behavior of extinct mega-fauna.

M Spilde; A Lanzirotti; C Qualls; G Phillips; A Ali; L Agenbroad; O Appenzeller

2011-12-31

453

A geometrical derivation of the Dirac equation  

E-print Network

We give a geometrical derivation of the Dirac equation by considering a spin-1/2 particle travelling with the speed of light in a cubic spacetime lattice. The mass of the particle acts to flip the multi-component wavefunction at the lattice sites. Starting with a difference equation for the case of one spatial and one time dimensions, we generalize the approach to higher dimensions. Interactions with external electromagnetic and gravitational fields are also considered. One logical interpretation is that only at the lattice sites is the spin-1/2 particle aware of its mass and the presence of external fields.

Y. Jack Ng; H. van Dam

2003-02-04

454

Proca equations derived from first principles  

E-print Network

Gersten has shown how Maxwell equations can be derived from first principles, similar to those which have been used to obtain the Dirac relativistic electron equation. We show how Proca equations can be also deduced from first principles, similar to those which have been used to find Dirac and Maxwell equations. Contrary to Maxwell equations, it is necessary to introduce a potential in order to transform a second order differential equation, as the Klein-Gordon equation, into a first order differential equation, like Proca equations.

Michel Gondran

2009-01-21

455

Orientation of perylene derivatives on semiconductor surfaces  

Microsoft Academic Search

The orientation of the perylene derivatives 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) and N,N?-dimethyl-3,4,9,10-perylenetetracarboxylic diimide (DiMe-PTCDI) on sulphur passivated GaAs(100) surfaces and its impact on the optical properties were studied by means of near-edge X-ray absorption fine structure spectroscopy (NEXAFS), Raman spectroscopy, and variable angle spectroscopic ellipsometry (VASE). NEXAFS shows that PTCDA molecules lie flat on the substrate with their molecular plane parallel

T. U. Kampen; G. Salvan; A. Paraian; C. Himcinschi; A. Yu. Kobitski; M. Friedrich; D. R. T. Zahn

2003-01-01

456

Paracyclophane derivatives in frustrated Lewis pair chemistry.  

PubMed

The metal-free activation of hydrogen was achieved using [2.2]paracyclophane-derived bisphosphines as Lewis base in frustrated Lewis pair chemistry. The rigid scaffold allows the orientation of functional groups so that steric aspects can be studied without altering the electronic nature. Depending on the geometry, structurally different phosphonium hydridoborates were generated when the frustrated Lewis pairs were exposed to hydrogen. The bisphosphines were applied in the 1,4-hydrosilylation-hydrogenation domino reaction providing access to secondary silyl-protected alcohols from enones in one step. Additionally, the planar-chiral scaffold was applied for the synthesis of novel enantiopure Lewis acids and Lewis bases. PMID:23111727

Greb, Lutz; Paradies, Jan

2013-01-01

457

NASP derived vehicles - Not just to space  

NASA Astrophysics Data System (ADS)

NASP-derived vehicles (NDVs) are presently noted to include not only exoatmospheric launch vehicles but also hypersonic cruisers. A conceptual development status evaluation is presented for such hypersonic aircraft, with a view to their likely military and civilian missions and the technical issues that remain to be solved for their implementation. Attention is given to plausible NDV configurations, propulsion systems, and performance goals for Mach 4.0 fighter-bomber, Mach 5.0 commercial/military transport, Mach 10.0 long-range cruiser, and SSTO launch vehicle.

Johnson, Donald B.; Espinosa, Angel M.; Althuis, Jeffrey S.

1992-12-01

458

Validation of an Experimentally Derived Uncertainty Model  

NASA Technical Reports Server (NTRS)

The results show that uncertainty models can be obtained directly from system identification data by using a minimum norm model validation approach. The error between the test data and an analytical nominal model is modeled as a combination of unstructured additive and structured input multiplicative uncertainty. Robust controllers which use the experimentally derived uncertainty model show significant stability and performance improvements over controllers designed with assumed ad hoc uncertainty levels. Use of the identified uncertainty model also allowed a strong correlation between design predictions and experimental results.

Lim, K. B.; Cox, D. E.; Balas, G. J.; Juang, J.-N.

1996-01-01

459

Black Holes in Higher-Derivative Gravity  

E-print Network

Extensions of Einstein gravity with higher-order derivative terms arise in string theory and other effective theories, as well as being of interest in their own right. In this paper we study static black-hole solutions in the example of Einstein gravity with additional quadratic curvature terms. A Lichnerowicz-type theorem simplifies the analysis by establishing that they must have vanishing Ricci scalar curvature. By numerical methods we then demonstrate the existence of further black-hole solutions over and above the Schwarzschild solution. We discuss some of their thermodynamic properties, and show that they obey the first law of thermodynamics.

Lu, H; Pope, C N; Stelle, K S

2015-01-01

460

Synthesis and cytotoxicity study of alkannin derivatives.  

PubMed

Alkannin derivatives (3-19) were prepared through the reaction of beta,beta-dimethylacrylalkannin (1), the most abundant isohexenylnaphthazarin isolated from the roots of Arnebia euchroma, with different types of nucleophiles such as amines and thiols in the absence or presence of a reducing agent. The cytotoxicities of 1-8, 10-14 and 19 against four human carcinoma cell line (GLC-82, CNE2, Bel-7402, K-562) were found to be markedly higher than that of the naturally occurring beta,beta-dimethylacrylalkannin (1) and acetylalkannin (2). This study also shed light on the understanding of the biological activities in terms of the chemical reactivity of alkannins. PMID:15337288

Huang, Zhi-Shu; Wu, Hai-Qiang; Duan, Zhi-Fang; Xie, Bing-Fen; Liu, Zong-Chao; Feng, Gong-Kan; Gu, Lian-Quan; Chan, Albert S C; Li, Yue-Ming

2004-09-01

461

Geometric derivation of the chronometric redshift.  

PubMed Central

The chronometric redshift-distance relation z = tan 2(1/2rho), where rho is the distance in radians in the Einstein metric, is derived by an elementary geometric analysis comparable to that in traditional analysis of the expanding universe model. The differential dTt of Einstein time evolution Tt through time t, as applied to the local Minkowski coordinates x, takes the form sec2(1/2t). At the point of observation t = rho, implying that for a sufficiently localized source, observed wave lengths are a factor of sec2(1/2rho) greater than the corresponding emitted wave lengths. PMID:11607440

Segal, I E

1993-01-01

462

[Synthesis of potential CCK antagonist quinazolone derivatives].  

PubMed

An original route has been found for the synthesis of [1,4]diazepino-quinazolones, a new ring system of heterocondensed quinazolones. These anthranilicacid-alanin-beta-alanin cyclopeptide derivatives constitute a structural moiety of asperlicin, the first natural cholecystokinin antagonist alkaloid. These compounds are therefore potential CCK antagonists. The new compounds were prepared via condensation of 2-amino-alkyl-quinazolones, obtained from 2-alkyl-quinazolones by side-chain substitution, with 1,3-bifunctional-reagents. We studied the cyclisation process under basic, acidic and phase-transfer catalyzed conditions. The structures of the synthesized compounds were characterized by IR, UV and NMR spectroscopy. PMID:7572196

Szabó, M; Kökösi, J; Orfi, L

1995-07-01

463

Derivation of an Applied Nonlinear Schroedinger Equation.  

SciTech Connect

We derive from first principles a mathematical physics model useful for understanding nonlinear optical propagation (including filamentation). All assumptions necessary for the development are clearly explained. We include the Kerr effect, Raman scattering, and ionization (as well as linear and nonlinear shock, diffraction and dispersion). We explain the phenomenological sub-models and each assumption required to arrive at a complete and consistent theoretical description. The development includes the relationship between shock and ionization and demonstrates why inclusion of Drude model impedance effects alters the nature of the shock operator. Unclassified Unlimited Release

Pitts, Todd Alan; Laine, Mark Richard; Schwarz, Jens; Rambo, Patrick K.; Karelitz, David B.

2015-01-01

464

24-norhopene derivatives from Diatenopteryx sorbifolia.  

PubMed

Two new hopene derivatives, 3 beta,6 beta-dihydroxy-21 alpha H-24-norhopa-4(23),22(29)-diene (1) and 3 beta,5 beta-dihydroxy-6 beta-[(4-hydroxybenzoyl)oxy]-21 alpha H-24-norhopa-4(23),22(29)-diene (2), together with cleomiscosin B (3) and 5,6-dimethoxy-7-hydroxycoumarin (umckalin), were isolated from the timber of Diatenopteryx sorbifolia. This is the first isolation of the norhopene skeleton from nature. The structures of the isolates were established by spectroscopic analysis. PMID:9322363

Chávez, J P; David, J M; Yang, S W; Cordell, G A

1997-09-01

465

Diphenylurea Derivatives Induce Somatic Embryogenesis in Citrus  

Microsoft Academic Search

The present research investigates the possibility that three diphenylurea (DPU) derivatives, N-phenyl-N?-benzothiazol-6-ylurea (PBU), N,N?-bis-(2,3-methilendioxyphenyl)urea (2,3-MDPU) and N,N?-bis-(3,4-methilendioxyphenyl)urea (3,4-MDPU), stimulate the induction of somatic embryogenesis in three Citrus species. The hypothetical embryogenic activity was assessed using stigma and styles of Citrus myrtifolia Raf., Citrus madurensis Lour. and Citrus limon (L.) Burm. The three compounds influenced the production of somatic embryos differently

Angela Carra; Fabio De Pasquale; Ada Ricci; Francesco Carimi

2006-01-01

466

Dietary derived compounds in cancer chemoprevention  

PubMed Central

Cancer chemoprevention is defined as the application of natural or synthetic agents to suppress or reverse cancer development and progression. In this field especially diet derived compounds have recently attracted researchers’ attention as potential therapeutics generally exerting low toxicity compared with regular drugs. This review presents a survey of recent findings concerning the most promising dietary chemopreventive agents such as green tea polyphenols (i.e. catechins), long-chain polyunsaturated fatty acids, carotenoids, glucosinolates/isothiocyanates, vitamins (i.e. vitamin D and folate) and minerals (i.e. calcium and selenium). Molecular targets involved in intrinsic pathways affected by these natural compounds are also shortly discussed. PMID:23788916

Rzeski, Wojciech

2012-01-01

467

Developing market for waste-derived fuel  

SciTech Connect

Markets are developing for products such as closely specified fuel, graded compost and clean ferrous metal and the company in question is aiming to produce these from waste treatment projects. The plant used for the waste derived fuel consists of equipment such as plant feeders, a vertical hammer mill, a ballistic classifier, magnetic separators, shredders, dryers a densifying unit and the final product are dense pellets with good handling properties. The compost, which is produced from the undersize waste material is mixed with water or sewage sludge and processed by the Siloda biological system. It then goes to a maturation pile for 60 days from where it can be distributed.

Wilson, D.

1984-08-17

468

Anionic derivatives of uracil: fragmentation and reactivity.  

PubMed

Uracil is an essential biomolecule for terrestrial life, yet its prebiotic formation mechanisms have proven elusive for decades. Meteorites have been shown to contain uracil and the interstellar abundance of aromatic species and nitrogen-containing molecules is well established, providing support for uracil's presence in the interstellar medium (ISM). The ion chemistry of uracil may provide clues to its prebiotic synthesis and role in the origin of life. The fragmentation of biomolecules provides valuable insights into their formation. Previous research focused primarily on the fragmentation and reactivity of cations derived from uracil. In this study, we explore deprotonated uracil-5-carboxylic acid and its anionic fragments to elucidate novel reagents of uracil formation and to characterize the reactivity of uracil's anionic derivatives. The structures of these fragments are identified through theoretical calculations, further fragmentation, experimental acidity bracketing, and reactivity with several detected and potential interstellar species (SO2, OCS, CS2, NO, N2O, CO, NH3, O2, and C2H4). Fragmentation is achieved through collision induced dissociation (CID) in a commercial ion trap mass spectrometer, and all reaction rate constants are measured using a modification of this instrument. Experimental data are supported by theoretical calculations at the B3LYP/6-311++G(d,p) level of theory. Lastly, the astrochemical implications of the observed fragmentation and reaction processes are discussed. PMID:25036757

Cole, Callie A; Wang, Zhe-Chen; Snow, Theodore P; Bierbaum, Veronica M

2014-09-01

469

Derive capillary pressure from well logs  

SciTech Connect

A new approach has been developed to estimate in-situ capillary pressure and relative permeability characteristics in the transition zone. The technique is based on incorporating petrophysical data measured on core samples with well log analysis. Relative permeability can be determined for both drainage and inhibition conditions using the matched capillary pressure data. A technique has been developed to extrapolate petro-physical data where core data is absent or not representative of in-situ conditions. It is based on using log data to derive a water saturation vs. depth profile in the transition zone of the formation of interest. The log-derived water saturation distribution is then correlated to generalized capillary pressure curves typical of the formation studied. The capillary pressure type curves are generated from available core data and other petrophysical information. Relative permeability curves are then generated using correlations based on Purcell's model. The technique can be used in multi-layered and homogeneous reservoirs provided that one homogeneous layer is at least 20 ft thick.

Ibrahim, A. (Suez Canal Univ. (Egypt)); Desbrandes, R.; Bassiouni, Z. (Louisiana State Univ., Baton Rouge, LA (United States))

1994-07-01

470

Tulczyjew Triples in Higher Derivative Field Theory  

E-print Network

The geometrical structure known as Tulczyjew triple has been used with success in analytical mechanics and first order field theory to describe a wide range of physical systems including Lagrangian/Hamiltonian systems with constraints and/or sources, or with singular Lagrangian. Starting from the first principles of the variational calculus we derive Tulczyjew triples for classical field theories of arbitrary high order, i.e.~depending on arbitrary high derivatives of the fields. A first triple appears as the result of considering higher order theories as first order ones with configurations being constrained to be holonomic jets. A second triple is obtained after a reduction procedure aimed at getting rid of nonphysical degrees of freedom. This picture we present is fully covariant and complete: it contains both Lagrangian and Hamiltonian formalisms, in particular the Euler-Lagrange equations. Notice that, the required Geometry of jet bundles is affine (as opposed to the linear Geometry of the tangent bundle). Accordinlgy, the notions of affine duality and affine phase space play a distinguished role in our picture. In particular the Tulczyjew triples in this paper consist of morphisms of double affine-vector bundles which, moreover, preserve suitable presymplectic structures.

Katarzyna Grabowska; Luca Vitagliano

2014-06-25

471

Thermal electron heating rate: A derivation  

NASA Technical Reports Server (NTRS)

The thermal electron heating rate is an important heat source term in the ionospheric electron energy balance equation, representing heating by photoelectrons or by precipitating higher energy electrons. A formula for the thermal electron heating rate is derived from the kinetic equation using the electron-electron collision operator as given by the unified theory of Kihara and Aono. This collision operator includes collective interactions to produce a finite collision operator with an exact Coulomb logarithm term. The derived heating rate O(e) is the sum of three terms, O(e) = O(p) + S + O(int), which are respectively: (1) primary electron production term giving the heating from newly created electrons that have not yet suffered collisions with the ambient electrons; (2) a heating term evaluated on the energy surface m(e)/2 = E(T) at the transition between Maxwellian and tail electrons at E(T); and (3) the integral term representing heating of Maxwellian electrons by energetic tail electrons at energies ET. Published ionospheric electron temperature studies used only the integral term O(int) with differing lower integration limits. Use of the incomplete heating rate could lead to erroneous conclusions regarding electron heat balance, since O(e) is greater than O(int) by as much as a factor of two.

Hoegy, W. R.

1983-01-01

472

Primer on electricity futures and other derivatives  

SciTech Connect

Increased competition in bulk power and retail electricity markets is likely to lower electricity prices, but will also result in greater price volatility as the industry moves away from administratively determined, cost-based rates and encourages market-driven prices. Price volatility introduces new risks for generators, consumers, and marketers. Electricity futures and other derivatives can help each of these market participants manage, or hedge, price risks in a competitive electricity market. Futures contracts are legally binding and negotiable contracts that call for the future delivery of a commodity. In most cases, physical delivery does not take place, and the futures contract is closed by buying or selling a futures contract on or near the delivery date. Other electric rate derivatives include options, price swaps, basis swaps, and forward contracts. This report is intended as a primer for public utility commissioners and their staff on futures and other financial instruments used to manage price risks. The report also explores some of the difficult choices facing regulators as they attempt to develop policies in this area.

Stoft, S.; Belden, T.; Goldman, C.; Pickle, S.

1998-01-01

473

Antistaphylococcal activity of novel salicylanilide derivatives.  

PubMed

This study examined the antibacterial properties of nineteen benzoxazole, isoniazid, ethionamide and salicylanilide derivatives against Staphylococcus aureus (S. aureus). It was found that three salicylanilide-derived compounds demonstrated antistaphylococcal activity: 5-Chloro-2-hydroxy-N-(4-(trifluoromethyl)phenyl)benzamide (5-Cl-4'-CF3- SAL), 4-chloro-2-(3-chlorophenylcarbamyoyl)phenyl)-2-(benzyloxycarbonylamino)propanoate (AIM31) and 4-chloro-2- (4-(trifluoromethyl)phenylcarbamoyl)phenyl acetate (AIM33). Investigation of the chemical structures of these three compounds and comparison with a non-inhibitory salicylanilide compound (i.e. 5,3'-diCl-SAL) illustrated that different combinations of chemical groups at defined positions on the salicylanilide core structure had a marked influence on antistaphylococcal activity. The most effective compound was AIM33 which inhibited staphylococcal growth and displayed an initial MIC value of 3.12 ?g ml(-1) and subsequent investigation revealed that an MIC as low as of 0.5 ?g ml(-1) was achievable. In this case, the dual presence of a trifluoromethyl group and an acetylated phenolic hydroxyl to the salicylanilide core structure led to greatly enhanced activity. PMID:21644919

Mollaghan, Annmarie; Vinsova, Jarmila; Imramovsky, Ales; Cotter, Lesley; Lucey, Brigid; O'Mahony, Jim; Costelloe, Aisling; Coffey, Aidan

2012-03-01

474

Kalman-predictive-proportional-integral-derivative (KPPID)  

SciTech Connect

With third generation synchrotron X-ray sources, it is possible to acquire detailed structural information about the system under study with time resolution orders of magnitude faster than was possible a few years ago. These advances have generated many new challenges for changing and controlling the state of the system on very short time scales, in a uniform and controlled manner. For our particular X-ray experiments on crystallization or order-disorder phase transitions in metallic alloys, we need to change the sample temperature by hundreds of degrees as fast as possible while avoiding over or under shooting. To achieve this, we designed and implemented a computer-controlled temperature tracking system which combines standard Proportional-Integral-Derivative (PID) feedback, thermal modeling and finite difference thermal calculations (feedforward), and Kalman filtering of the temperature readings in order to reduce the noise. The resulting Kalman-Predictive-Proportional-Integral-Derivative (KPPID) algorithm allows us to obtain accurate control, to minimize the response time and to avoid over/under shooting, even in systems with inherently noisy temperature readings and time delays. The KPPID temperature controller was successfully implemented at the Advanced Photon Source at Argonne National Laboratories and was used to perform coherent and time-resolved X-ray diffraction experiments.

Fluerasu, A.; Sutton, M. (McGill)

2004-12-17

475

Antimicrobial activity of basic cholane derivatives, VIII.  

PubMed

Two series of new compounds derived from deoxycholic acid have been synthesized: 3,12-dioxo-5 beta-cholan-24-N-substituted amides and their 3 beta-amino and 3 beta-N-alkylamino derivatives. The first series of five compounds 1-5 carries at C-24 the residue of benzylamine, morpholine, diethanolamine, N,N-diethyl-ethylenediamine, and N-methylpiperazine. The second series of twenty compounds 1A-D - 5A-D was prepared by means of reductive amination starting from the compounds of the first series. This reaction proved to be regioselective and stereospecific: it attacks only C-3 of the steroid moiety and introduces the following axial beta-oriented substituents: amino, methylamino, ethylamino, and benzylamino. The compounds of the first series showed moderate scattered antimicrobial activity; while introduction of the 3 beta-amino and 3 beta-N-alkylamino residue greatly increased activity towards Gram (+) strains; even yeast and fungi appear to be sensitive towards this last series of compounds. The results have been discussed with respect to the nature of the substituents both at C-3 and C-24, the highest activity being associated to the hydrophobicity of these residues. PMID:2619517

Bellini, A M; Quaglio, M P; Mencini, E; Guarneri, M; Cavazzini, G; Fini, A

1989-12-01

476

Isocoumarin derivatives and benzofurans from a sponge-derived Penicillium sp. fungus.  

PubMed

Ten new fungal metabolites, including three hydroisocoumarins, penicimarins A-C (1-3), three isocoumarins, penicimarins D-F (6-8), and four benzofurans, penicifurans A-D (11-14), together with four known isocoumarin derivatives (4, 5, 9, 10), were obtained from the sponge-derived fungus Penicillium sp. MWZ14-4, collected from the South China Sea. Their planar structures and relative configurations were elucidated by detailed analysis of spectroscopic data and by comparison with related known compounds. The absolute configurations of 1-4 were assigned by the modified Mosher's method and TDDFT ECD calculations together with comparison of their CD spectra. Compound 1 represents a rare naturally occurring isocoumarin derivative with 4-substitution, but no substituent at the 3-position. These compounds were evaluated for antibacterial activities and cytotoxic activities in vitro. Among them, penicifuran A (11) exhibited inhibitory activity against Staphylococcus albus with an MIC value of 3.13 ?M. PMID:23477451

Qi, Jun; Shao, Chang-Lun; Li, Zhi-Yong; Gan, Li-She; Fu, Xiu-Mei; Bian, Wen-Tao; Zhao, Hong-Ying; Wang, Chang-Yun

2013-04-26

477

Numerical approach to the Caputo derivative of the unknown function  

NASA Astrophysics Data System (ADS)

If a function can be explicitly expressed, then one can easily compute its Caputo derivative by the known methods. If a function cannot be explicitly expressed but it satisfies a differential equation, how to seek Caputo derivative of such a function has not yet been investigated. In this paper, we propose a numerical algorithm for computing the Caputo derivative of a function defined by a classical (integer-order) differential equation. By the properties of Caputo derivative derived in this paper, we can change the original typical differential system into an equivalent Caputo-type differential system. Numerical examples are given to support the derived numerical method.

Zeng, Fanhai; Li, Changpin

2013-10-01

478

Genetic instability in calamondin ( Citrus madurensis Lour.) plants derived from somatic embryogenesis induced by diphenylurea derivatives  

Microsoft Academic Search

Somatic embryos were regenerated in vitro from calamondin style–stigma explants cultured in the presence of N\\u000a 6-benzylaminopurine (BAP) cytokinin and three synthetic phenylurea derivatives, N-(2-chloro-4-pyridyl)-N-phenylurea (4-CPPU), N-phenyl-N?-benzothiazol-6-ylurea (PBU) and N,N?-bis-(2,3-methilendioxyphenyl)urea (2,3-MDPU). The phenylurea derivative compounds tested at micromolar level (12 ?M) were\\u000a able to induce a percentage of responsive explants significantly higher from that obtained with BAP and hormone-free (HF)\\u000a conditions.

Mirko Siragusa; Angela Carra; Lidia Salvia; Anna Maria Puglia; Fabio De Pasquale; Francesco Carimi

2007-01-01

479

Antimalarial Activities of Dermaseptin S4 Derivatives  

PubMed Central

The hemolytic antimicrobial peptide dermaseptin S4 was recently shown to exert antimalarial activity. In this study, we attempted to understand the underlying mechanism(s) and identify derivatives with improved antimalarial activity. A number of dermaseptin S4 derivatives inhibited parasite growth with a 50% inhibitory concentration (IC50) in the micromolar range. Among these, the substituted S4 analog K4K20-S4 was the most potent (IC50 = 0.2 ?M), while its shorter version, K4-S4(1–13)a, retained a considerable potency (IC50 = 6 ?M). Both K4K20-S4 and K4-S4(1–13)a inhibited growth of the parasites more at the trophozoite stage than at the ring stage. Significant growth inhibition was observed after as little as 1 min of exposure to peptides and proceeded with nearly linear kinetics. The peptides selectively lysed infected red blood cells (RBC) while having a weaker effect on noninfected RBC. Thus, K4K20-S4 lysed trophozoites at concentrations similar to those that inhibited their proliferation, but trophozoites were >30-fold more susceptible than normal RBC to the lytic effect of K4K20-S4, the most hemolytic dermaseptin. The same trend was observed with K4-S4(1–13)a. The d isomers of K4K20-S4 or K4-S4(1–13)a were as active as the l counterparts, indicating that antimalarial activity of these peptides, like their membrane-lytic activity, is not mediated by specific interactions with a chiral center. Moreover, dissipation of transmembrane potential experiments with infected cells indicated that the peptides induce damage in the parasite's plasma membrane. Fluorescence confocal microscopy analysis of treated infected cells also indicated that the peptide is able to find its way through the complex series of membranes and interact directly with the intracellular parasite. Overall, the data showed that dermaseptins exert antimalarial activity by lysis of infected cells. Dermaseptin derivatives are also able to disrupt the parasite plasma membrane without harming that of the host RBC. PMID:10952593

Krugliak, Miriam; Feder, Rina; Zolotarev, Vadim Y.; Gaidukov, Leonid; Dagan, Arie; Ginsburg, Hagai; Mor, Amram

2000-01-01

480

Equilibrium dialysis using chromophoric sugar derivatives.  

PubMed

Equilibrium dialysis has been used to examine the binding affinity of ligands to proteins. It is a simple and reliable method, which requires only inexpensive equipment. For analysis of lectin-sugar interactions, the lectin and sugar are placed in the individual chambers separated by the membrane to allow the sugar to diffuse into the lectin chamber. After equilibrium has been reached, the concentrations of the sugar in both chambers are determined to evaluate the sugar-binding affinity of lectin. In this chapter, an example of the equilibrium dialysis experiment using the chromophoric derivatives of galactose and N-acetylgalactosamine is demonstrated, which reveals the difference in the affinity as well as specificities of two different carbohydrate-binding sites present in the B-chains of the plant lectin ricin. PMID:25117234

Hatakeyama, Tomomitsu

2014-01-01

481

Modular synthesis of oxazolines and their derivatives.  

PubMed

A class of modular oxazolines and their derivatives 1-5 were synthesized with moderate to excellent yields using a simple one-pot method; 4 x 3 bis-oxazolines were obtained, as expected, from each of the three reactions of 1,4-dicyanobenzene, 1,3-dicyanobenzene, and 1,2-dicyanobenzene with optically active amino alcohols in chlorobenzene under dry, anaerobic conditions. ZnCl(2) was used as a Lewis acid catalyst. Direct condensation of 1, 2-bis(cyanomethyl) benzene or 2-cyanophenylacetonitrile did not yield the target products, but two series of novel compounds (4 and 5) were isolated and their structures were confirmed by X-Ray analysis. All products (1-5) were characterized by NMR, IR, and MS. PMID:19138088

Mei, Luo; Hai, Zhang Jia; Jie, Sun; Ming, Zhou Shi; Hao, Yin; Liang, Hu Ke

2009-03-01

482

Overview of medically important antifungal azole derivatives.  

PubMed Central

Fungal infections are a major burden to the health and welfare of modern humans. They range from simply cosmetic, non-life-threatening skin infections to severe, systemic infections that may lead to significant debilitation or death. The selection of chemotherapeutic agents useful for the treatment of fungal infections is small. In this overview, a major chemical group with antifungal activity, the azole derivatives, is examined. Included are historical and state of the art information on the in vitro activity, experimental in vivo activity, mode of action, pharmacokinetics, clinical studies, and uses and adverse reactions of imidazoles currently marketed (clotrimazole, miconazole, econazole, ketoconazole, bifonazole, butoconazole, croconazole, fenticonazole, isoconazole, oxiconazole, sulconazole, and tioconazole) and under development (aliconazole and omoconazole), as well as triazoles currently marketed (terconazole) and under development (fluconazole, itraconazole, vibunazole, alteconazole, and ICI 195,739). PMID:3069196

Fromtling, R A

1988-01-01

483

Calixradialenes: calixarene derivatives with exocyclic double bonds.  

PubMed

Reaction of dioxocalix[4]arene 7 with MeLi followed by 2-fold elimination of water yielded calixarene 8 possessing exocyclic double bonds at two adjacent bridges. Calixarene 8 exists in tetrachloroethane-d2 solution at rt, as a 2.3:1 mixture of the 1,3-alternate and partial cone conformers. Keto[n]calixarenes (n = 5, 6) were prepared via hydrolysis of the bromocalixarenes 11 and 12, followed by CrO3 oxidation of the respective hydroxymethylene derivatives. Addition of MeLi to the ketocalix[n]arenes (n = 4, 5 and 6) followed by elimination of water yielded the corresponding calix[n]radialenes. Calix[5]- and calix[6]radialenes adopt in the crystal irregular alternate (i.e., noncone) conformations. PMID:24364562

Poms, David; Itzhak, Norbert; Kuno, Lev; Biali, Silvio E

2014-01-17

484

Derivation of Quantum Theory from Feynman's Rules  

E-print Network

Feynman's formulation of quantum theory is remarkable in its combination of formal simplicity and computational power. However, as a formulation of the abstract structure of quantum theory, it is incomplete as it does not account for most of the fundamental mathematical structure of the standard von Neumann-Dirac formalism such as the unitary evolution of quantum states. In this paper, we show how to reconstruct the entirety of the finite-dimensional quantum formalism starting from Feynman's rules with the aid of a single new physical postulate, the no-disturbance postulate. This postulate states that a particular class of measurements have no effect on the outcome probabilities of subsequent measurements performed. We also show how it is possible to derive both the amplitude rule for composite systems of distinguishable subsystems and Dirac's amplitude-action rule, each from a single elementary and natural assumption, by making use of the fact that these assumptions must be consistent with Feynman's rules.

Philip Goyal

2014-03-14

485