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Sample records for benzothiazoles

  1. Sedimentary environment indicators: Benzothiazole and its derivatives

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Benzothiazoles distributional characteristics of crude oils and non-hydrocarbon fractions of source rocks in Mangya depression of the Qaidam Basin, Lunnan oil field in the Tarim Basin, Kelamayi oil field in the Junggar Basin and the Tulufan Basin oil field were analyzed. It was found that the distributions of benzothiazole are remarkable diversity in different sedimentary environmental oils. The swamp crude oils contain high quantity of benzothiazole and relatively high quantity of alkylthio-benzothiazole and 2(3H)-benzothiazolone. But the quantity of the 2,2′-dithiobis- ben-zothiazole is relatively low. The abundance of benzothiazole and 2,2′-dithiobis-benzothiazole are relatively high in semi-brackish water lacustrine crude oils, but the quantity of alkylthio-benzothiazole and 2(3H)-benzothiazolone are rela-tively low. The benzothiazoles belong to weak acid and mild base compound, and their stabilization conditions relate to their environmental medium. The nitrogenous bases are in favor of alkalescence environment, while weak acid nitroge-nous compounds are the main stable products under the weak acid environment. Benzothiazoles have great signifi-cance in identifying the oil- and gas-formed environment and the geochemistry study of non-hydrocarbon fraction in the future.

  2. Biological Aspects of Emerging Benzothiazoles: A Short Review

    Directory of Open Access Journals (Sweden)

    Ruhi Ali

    2013-01-01

    Full Text Available In recent years heterocyclic compounds analogues and derivatives have attracted wide attention due to their useful biological and pharmacological properties. Benzothiazole is among the usually occurring heterocyclic nuclei in many marine as well as natural plant products. Benzothiazole is a privileged bicyclic ring system with multiple applications. It is known to exhibit a wide range of biological properties including anticancer, antimicrobial, and antidiabetic, anticonvulsant, anti-inflammatory, antiviral, antitubercular activities. A large number of therapeutic agents are synthesized with the help of benzothiazole nucleus. During recent years there have been some interesting developments in the biological activities of benzothiazole derivatives. These compounds have special significance in the field of medicinal chemistry due to their remarkable pharmacological potentialities. This review is mainly an attempt to present the research work reported in the recent scientific literature on different biological activities of benzothiazole compounds.

  3. Mesogenic benzothiazole derivatives with methoxy substituents

    Indian Academy of Sciences (India)

    A K Prajapati; N L Bonde

    2006-03-01

    Two new mesogenic homologous series containing 6-methoxybenzothiazole ring at the terminus of the molecule, viz. 2-(4'--alkoxyphenylazo)-6-methoxybenzothiazoles and 2-[4'-(4"--alkoxybenzoyloxy) phenylazo]-6-methoxybenzothiazoles were synthesized. In series I, -butyloxy to -tetradecyloxy derivatives exhibit nematic mesophase. Smectic A mesophase commences from the -dodecyloxy derivative as a monotropic phase and is retained up to the last member synthesized. All the members of series II exhibit enantiotropic nematic mesophase. The mesomorphic properties of the present series are compared with other structurally related series to evaluate the effect of the benzothiazole ring and the methoxy substituent on mesomorphism.

  4. Biological Aspects of Emerging Benzothiazoles: A Short Review

    OpenAIRE

    Ruhi Ali; Nadeem Siddiqui

    2013-01-01

    In recent years heterocyclic compounds analogues and derivatives have attracted wide attention due to their useful biological and pharmacological properties. Benzothiazole is among the usually occurring heterocyclic nuclei in many marine as well as natural plant products. Benzothiazole is a privileged bicyclic ring system with multiple applications. It is known to exhibit a wide range of biological properties including anticancer, antimicrobial, and antidiabetic, anticonvulsant, anti-inflamma...

  5. Mikrobial and photolytic degradation of benzothiazoles in water and wastewater

    OpenAIRE

    Kirouani-Harani, Hafida

    2003-01-01

    Im Rahmen dieser Arbeit wurde eine analytische Methode für den Nachweis von Benzothiazolen entwickelt. Da Bakterien oft eine große Rolle bei der Transformation von organischen Stoffen in Wasser spielen, wurde der Bio-Abbau (anaerob/aerob) der Verbindungen untersucht. Desweitern wurde das photolytische Abbauverhalten der Verbindungen untersucht. Die polaren Benzothiazole wie Benzothiazol Sulfonsäure (BTSA) und Hydroxybenzothiazol (OHBT) können mit guten Wiederfindungsraten über polare Polymer-...

  6. Molecular Modeling and Spectroscopic Studies of Benzothiazole

    Directory of Open Access Journals (Sweden)

    V. Sathyanarayanmoorthi

    2013-01-01

    Full Text Available The Fourier Transform (FT infrared and FT-Raman spectra of benzothiazole (BT have been recorded and analyzed. The equilibrium geometry, bonding features, and harmonic vibrational frequencies have been investigated by ab initio and density functional theory (DFT methods. The assignments of the vibrational spectra have been carried out. The computed optimized geometric bond lengths and bond angles show good agreement with experimental data of the title compound. The calculated HOMO and LUMO energies indicate that charge transfer occurs within the molecule. Stability of the molecule due to conjugative interactions arising from charge delocalization has been analyzed using natural bond orbital (NBO analysis. The results show that the electron density (ED in the and antibonding orbital and second-order delocalization energies confirm the occurrence of intramolecular charge transfer (ICT. The calculated results were applied to simulate infrared and Raman spectra BT which show good agreement with recorded spectra.

  7. The thermodynamic properties of benzothiazole and benzoxazole

    Energy Technology Data Exchange (ETDEWEB)

    Steele, W.V.; Chirico, R.D.; Knipmeyer, S.E.; Nguyen, A.

    1991-08-01

    This research program, funded by the Department of Energy, Office of Fossil Energy, Advanced Extraction and Process Technology, provides accurate experimental thermochemical and thermophysical properties for key'' organic diheteroatom-containing compounds present in heavy petroleum feedstocks, and applies the experimental information to thermodynamic analyses of key hydrodesulfurization, hydrodenitrogenation, and hydrodeoxygenation reaction networks. Thermodynamic analyses, based on accurate information, provide insights for the design of cost-effective methods of heteroatom removal. The results reported here, and in a companion report to be completed, will point the way to the development of new methods of heteroatom removal from heavy petroleum. Measurements leading to the calculation of the ideal-gas thermodynamic properties are reported for benzothiazole and benzoxazole. Experimental methods included combustion calorimetry, adiabatic heat-capacity calorimetry, comparative ebulliometry, inclinded-piston gauge manometry, and differential-scanning calorimetry (d.s.c). Critical property estimates are made for both compounds. Entropies, enthalpies, and Gibbs energies of formation were derived for the ideal gas for both compounds for selected temperatures between 280 K and near 650 K. The Gibbs energies of formation will be used in a subsequent report in thermodynamic calculations to study the reaction pathways for the removal of the heteratoms by hydrogenolysis. The results obtained in this research are compared with values present in the literature. The failure of a previous adiabatic heat capacity study to see the phase transition in benzothiazole is noted. Literature vibrational frequency assignments were used to calculate ideal gas entropies in the temperature range reported here for both compounds. Resulting large deviations show the need for a revision of those assignments. 68 refs., 6 figs., 15 tabs.

  8. Occurrence and removal efficiencies of benzotriazoles and benzothiazoles in a wastewater treatment plant in Greece.

    Science.gov (United States)

    Asimakopoulos, Alexandros G; Ajibola, Akinranti; Kannan, Kurunthachalam; Thomaidis, Nikolaos S

    2013-05-01

    Despite the widespread use of benzotriazoles and benzothiazoles and the occurrence of these compounds in wastewater treatment plants (WWTPs), no earlier study has comprehensively examined their fate in WWTPs. In this study, an integrated liquid chromatography-tandem mass spectrometry (LC-ESI(+)MS/MS) method was developed and validated for simultaneous determination of four benzotriazoles and four benzothiazoles in dissolved and particulate phases of wastewater (raw and treated), and in dewatered sewage sludge. The target benzotriazoles (BTRs) were 1H-benzotriazole, 1-hydroxy-benzotriazole, tolyltriazole, and xylyltriazole (or 5,6-dimethyl-1H-benzotriazole), and the target benzothiazoles (BTHs) were benzothiazole, 2-hydroxy-benzothiazole, 2-methylthio-benzothiazole, and 2-amino-benzothiazole. The limits of detection ranged from 0.08 (2-methylthio-benzothiazole) to 17 ng/L (benzothiazole) for dissolved phase samples, and from 0.04 (2-methylthio-benzothiazole) to 13 ng/g dry weight (dw) (benzothiazole) for particular matter and sludge samples. The method was applied in the analysis of wastewater and sludge samples from the WWTP in Athens, Greece. All target chemicals were detected in wastewater samples, and in some cases the concentrations were significant, on the order of a few μg/L. In sludge samples, benzothiazole and tolyltriazole were present at the highest concentrations (174 and 116 ng/g dw, respectively). For benzotriazole and tolyltriazole, the removal efficiency was below 68%, and for benzothiazoles, the removal efficiency was greater than 64% in the activated sludge treatment process. Both BTRs and BTHs showed low solid-liquid distribution coefficients. PMID:23500410

  9. 5-Benzothiazole substituted pyrimidine derivatives as HCV replication (replicase) inhibitors.

    Science.gov (United States)

    Arasappan, Ashok; Bennett, Frank; Girijavallabhan, Vinay; Huang, Yuhua; Huelgas, Regina; Alvarez, Carmen; Chen, Lei; Gavalas, Stephen; Kim, Seong-Heon; Kosinski, Aneta; Pinto, Patrick; Rizvi, Razia; Rossman, Randall; Shankar, Bandarpalle; Tong, Ling; Velazquez, Francisco; Venkatraman, Srikanth; Verma, Vishal A; Kozlowski, Joseph; Shih, Neng-Yang; Piwinski, John J; MacCoss, Malcolm; Kwong, Cecil D; Clark, Jeremy L; Fowler, Anita T; Geng, Feng; Kezar, Hollis S; Roychowdhury, Abhijit; Reynolds, Robert C; Maddry, Joseph A; Ananthan, Subramaniam; Secrist, John A; Li, Cheng; Chase, Robert; Curry, Stephanie; Huang, Hsueh-Cheng; Tong, Xiao; Njoroge, F George

    2012-05-01

    Based on a previously identified HCV replication (replicase) inhibitor 1, SAR efforts were conducted around the pyrimidine core to improve the potency and pharmacokinetic profile of the inhibitors. A benzothiazole moiety was found to be the optimal substituent at the pyrimidine 5-position. Due to potential reactivity concern, the 4-chloro residue was replaced by a methyl group with some loss in potency and enhanced rat in vivo profile. Extensive investigations at the C-2 position resulted in identification of compound 16 that demonstrated very good replicon potency, selectivity and rodent plasma/target organ concentration. Inhibitor 16 also demonstrated good plasma levels and oral bioavailability in dogs, while monkey exposure was rather low. Chemistry optimization towards a practical route to install the benzothiazole moiety resulted in an efficient direct C-H arylation protocol.

  10. New mesogenic Schiff base esters comprising benzothiazole moiety:Synthesis and mesomorphic properties

    Institute of Scientific and Technical Information of China (English)

    Sie Tiong Ha; Teck Ming Koh; Guan Yeow Yeap; Hong Cheu Lin; Jun Kit Beh; Yip Foo Win; Peng Lim Boey

    2009-01-01

    A homologous series of Schiff base esters,6-methoxy-2-(2-hydroxy-4-alkanoyloxybenzylidenamino)benzothiazoles,comprising a benzothiazole moiety as the core was synthesized.All the members of this series exhibited an enantiotropic nematic phase.The azomethine linkage along with the lateral hydroxyl and terminal methoxyl groups were found to exert an effect on the mesomorphic properties.

  11. A fluorescent benzothiazole probe with efficient two-photon absorption

    Science.gov (United States)

    Echevarria, Lorenzo; Moreno, Iván; Camacho, José; Salazar, Mary Carmen; Hernández, Antonio

    2012-11-01

    In this work, we report the two-photon absorption of 2-[4-(dimethylamino)phenyl]-1,3-benzothiazole-6-carbonitrile (DBC) in DMSO solution pumping at 779 nm with a 10 ns pulse laser-Nd:YAG system. The obtained two-photon absorption cross-section in DBC (407 ± 18 GM) is considerably high. Because DBC is a novel compound and have high values of fluorescence quantum yield, this result is expected to have an impact in biomolecules detection, diagnosis and treatment of cancer. Similar structures have previously been reported to show remarkable antitumour effects.

  12. Synthesis and in vitro Evaluation of New Benzothiazole Derivatives as Schistosomicidal Agents

    OpenAIRE

    Mahran, Mona A; Samia William; Fatem Ramzy; Sembel, Amira M

    2007-01-01

    A series of benzothiazol-2-yl-dithiocarbamates 3a-d along with their copper complexes 4a-c were synthesized via the reaction of suitable alkyl, aralkyl or heteroaryl halides with the sodium salt of benzothiazol-2-yl-dithiocarbamic acid, followed by complexation with copper sulphate. N-(4-Acetyl-5-aryl-4,5-dihydro-1,3,4-thiadiazol-2-yl)-N-benzothiazol-2-yl-acetamides 7a-c were synthesized by cyclization of the appropriate thiosemicarbazones 6a-c in acetic anhydride. Selected compounds were scr...

  13. Synthesis and 11C-Radiolabelling of 2-Carboranyl Benzothiazoles

    Directory of Open Access Journals (Sweden)

    Kiran B. Gona

    2015-04-01

    Full Text Available Dicarba-closo-dodecaboranes, commonly known as carboranes, possess unique physico-chemical properties and can be used as hydrophobic moieties during the design of new drugs or radiotracers. In this work, we report the synthesis of two analogues of 2-(4-aminophenylbenzothiazole (a compound that was found to elicit pronounced inhibitory effects against certain breast cancer cell lines in vitro in which the phenyl ring has been substituted by a m-carborane cage. Two different synthetic strategies have been used. For the preparation of 1-(9-amino-1,7-dicarba-closo-dodecaboran-1-yl-benzo-thiazole, the benzothiazole group was first introduced on one of the cluster carbon atoms of m-carborane and the amine group was further attached in three steps. For the synthesis of 1-(9-amino-1,7-dicarba-closo-dodecaboran-1-yl-6-hydroxybenzothiazole, iodination was performed before introducing the benzothiazole group, and the amino group was subsequently introduced in six steps. Both compounds were radiolabelled with carbon-11 using [11C]CH3OTf as the labelling agent. Radiolabelling yields and radiochemical purities achieved should enable subsequent in vitro and in vivo investigations.

  14. Coumarin benzothiazole derivatives as chemosensors for cyanide anions

    Science.gov (United States)

    Wang, Kangnan; Liu, Zhiqiang; Guan, Ruifang; Cao, Duxia; Chen, Hongyu; Shan, Yanyan; Wu, Qianqian; Xu, Yongxiao

    2015-06-01

    Four coumarin benzothiazole derivatives, N-(benzo[d]thiazol-2-yl)-2-oxo-2H-chromene-3-carboxamide (1), (Z)-N-(3-methylbenzo[d]thiazol-2(3H)-ylidene)-2-oxo-2H-chromene-3-carboxamide (2), 7-(diethylamino)-N-(benzo[d]thiazol-2-yl)-2-oxo-2H-chromene-3-carboxamide (3) and (Z)-7-(diethylamino)-N-(3-methylbenzo[d]thiazol-2(3H)-ylidene)-2-oxo-2H-chromene-3-carboxamide) (4), have been synthesized. Their crystal structures, photophysical properties in acetonitrile and recognition properties for cyanide anions have been investigated. All the compounds are generally planar, especially compound 1 exhibits perfect planarity with dihedral angle between benzothiazolyl group and coumarin group being only 3.63°. Coumarin benzothiazole compounds 1 and 3 can recognize cyanide anions by Michael addition reaction and compound 3 exhibits color change from yellow to colorless and green fluorescence was quenched completely, which can be observed by naked eye. Coumarin benzothiazolyliden compound 4 can recognize cyanide anions with fluorescence turn-on response based on the copper complex ensemble displacement mechanism.

  15. Second-order Nonlinear Optical Properties of a Series of Benzothiazole Derivatives

    Institute of Scientific and Technical Information of China (English)

    LIU,Xiao-Juan; LENG,Wei-Nan; FENG,Ji-Kang; REN,Ai-Min; ZHOU,Xin

    2003-01-01

    The second- order nonlinear optical ( NLO ) properties of a series of benzothiazole derivatives were studied by use of the ZINDO-SOS method. These chromphores are formed by a donor-π-bridge-acceptor system, based on a nitro group connected with benzothiazole as the acceptor and a hydroxyl-functional amino group as the donor. For the purpose of comparison, we also designed molecules in which nitrobenzene is an acceptor. The calculation results indicate that benzothiazole derivatives exhibit larger second-order polarizabilities than nitrobenzene derivatives. In order to clarify the origin of the NLO response of these chromophores, their electron properties were investigated as well. The benzothiazole derivatives are good candidates for application in electro-optical device due to their high optical nonlinearities, good thermla and photonic stability.

  16. Synthesis and in Vitro Antiproliferative Evaluation of Some B-norcholesteryl Benzimidazole and Benzothiazole Derivatives

    OpenAIRE

    Jianguo Cui; Binbin Qi; Chunfang Gan; Zhipin Liu; Hu Huang; Qifu Lin; Dandan Zhao; Yanmin Huang

    2015-01-01

    Taking orostanal (a compound from a Japanese marine sponge, Stelletta hiwasaensis) as a lead compound, some novel B-norcholesteryl benzimidazole and benzothiazole derivatives were synthesized. The antiproliferative activity of the compounds against human cervical carcinoma (HeLa), human lung carcinoma (A549), human liver carcinoma cells (HEPG2) and normal kidney epithelial cells (HEK293T) was assayed. The results revealed that the benzimidazole group was a better substituent than benzothiazol...

  17. Highly selective palladium–benzothiazole carbene-catalyzed allylation of active methylene compounds under neutral conditions

    OpenAIRE

    Antonio Monopoli; Pietro Cotugno; Zambonin, Carlo G.; Francesco Ciminale; Angelo Nacci

    2015-01-01

    The Pd–benzothiazol-2-ylidene complex I was found to be a chemoselective catalyst for the Tsuji–Trost allylation of active methylene compounds carried out under neutral conditions and using carbonates as allylating agents. The proposed protocol consists in a simplified procedure adopting an in situ prepared catalyst from Pd2dba3 and 3-methylbenzothiazolium salt V as precursors. A comparison of the performance of benzothiazole carbene with phosphanes and an analogous imidazolium carbene ligand...

  18. Mesomorphic behavior of new benzothiazole liquid crystals having Schiff base linker and terminal methyl group

    Institute of Scientific and Technical Information of China (English)

    Sie Tiong Ha; Kok Leei Foo; Hong Cheu Lin; Masato M.Ito; Kazuma Abe; Kenji Kunbo; S.Sreehari Sastry

    2012-01-01

    A homologous series of heterocycles,6-methyl-2-(4-alkoxybenzylidenamino)benzothiazoles,were synthesized and characterized using FT-IR,1H and 13C NMR and mass spectrometric analysis.Enantiotropic nematic phase was observed for shorter members.Smectic A phase only emerged from octyloxy derivative onwards.The terminal methyl group at the benzothiazole fragment and the Schiff base linkage influenced the mesomorphic behavior of the present series.

  19. Imidazo[2,1-b]benzothiazoles. II. Synthesis and antiinflammatory activity of some imidazo[2,1-b]benzothiazoles.

    Science.gov (United States)

    El-Shorbagi, A N; Sakai, S; el-Gendy, M A; Omar, N; Farag, H H

    1989-11-01

    3-[2-[p-(Un)substituted phenyl]imidazo [2,1-b]benzothiazol-3- yl]propionic acid derivatives (2a--e) were prepared via the interaction of the corresponding 2-[p-(un)substituted phenyl]imidazo[2,1-b]benzothiazoles (1a--e) with acrylic acid in the presence of acetic anhydride and acetic acid. Esterification of 2a--e produced methyl esters (3a--e). Upon the interaction of 3a with m-chloroperbenzoic acid, the S-dioxide (4a) was obtained. Compound 5a was prepared from 4a by alkaline hydrolysis. Vilsmeier formylation for 1a--e produced novel [2-[p-(un)substituted phenyl]imidazo[2,1-b]benzothiazol-3- yl]formaldehyde derivatives (6a--e). Derivatives 6a--e reacted with ethyl bromoacetate to give ethyl 3-hydroxy-3-[2-[p-(un)substituted phenyl]imidazo[2,1-b]benzothiazol- 3-yl]propionate esters (7a--e). Compound dl-7a was resolved with l-(+)-tartaric acid. Compounds 2a--e showed weak or no activity in the carrageein-induced paw edema assay. Compound 4a significantly inhibited the leakage of pontamine-sky blue dye into the peritoneal cavity of mice, in the capillary permeability inhibition assay. Compound 5a inhibited the writhing by 62% in the acetic acid-induced writhing assay.

  20. Synthesis and in vitro Evaluation of New Benzothiazole Derivatives as Schistosomicidal Agents

    Directory of Open Access Journals (Sweden)

    Mona A Mahran

    2007-03-01

    Full Text Available A series of benzothiazol-2-yl-dithiocarbamates 3a-d along with their copper complexes 4a-c were synthesized via the reaction of suitable alkyl, aralkyl or heteroaryl halides with the sodium salt of benzothiazol-2-yl-dithiocarbamic acid, followed by complexation with copper sulphate. N-(4-Acetyl-5-aryl-4,5-dihydro-1,3,4-thiadiazol-2-yl-N-benzothiazol-2-yl-acetamides 7a-c were synthesized by cyclization of the appropriate thiosemicarbazones 6a-c in acetic anhydride. Selected compounds were screened for in vitro schistosomicidal activity against Schistosoma mansoni at three different dosage levels (10, 50 and 100 μg/ mL. Three of these products, 4a-c, showed schistosomicidal activity similar to praziquantel, with 100% worm mortality at 10 μg/mL. These compounds would constitute a new class of potent schistosomicidal agents.

  1. Regioselective Synthesis of Some Pyrazole Scaffolds Attached to Benzothiazole and Benzimidazole Moieties

    Directory of Open Access Journals (Sweden)

    Nabila A. Kheder

    2014-01-01

    Full Text Available Condensation of 2-(benzothiazol-2-ylacetonitrile (1 or 2-(1-methyl-1H-benzimidazol-2-ylacetonitrile (2 with thiophene-2-carbaldehyde afforded the corresponding acrylonitrile derivatives 3 or 4, respectively. The 1,3-dipolar cycloaddition reaction of the acrylonitrile 3 or 4 with nitrile-imine 6 gave novel pyrazole derivatives pendant to benzothiazole and benzimidazole. The pyrazoline derivative 7 was converted into the corresponding pyrazole derivative 11 via thermal elimination of hydrogen cyanide upon heating in sodium ethoxide solution. The structures of the synthesized products were confirmed by IR, 1H NMR, and mass spectral techniques.

  2. A concise, efficient synthesis of sugar-based benzothiazoles through chemoselective intramolecular C-S coupling

    KAUST Repository

    Shen, Chao

    2012-01-01

    Sugar-based benzothiazoles are a new class of molecules promising for many biological applications. Here, we have synthesized a wide range of sugar-based benzothiazoles from readily accessible glycosyl thioureas by chemoselective, palladium-catalyzed C-S coupling reactions. Corroborated by theoretical calculations, a mechanistic investigation indicates that the coordination to the palladium by a pivaloyl carbonyl group and the presence of intramolecular hydrogen bonding play important roles in the efficiency and chemoselectivity of reaction. These fluorescent glycoconjugates can be observed to readily enter mammalian tumor cells and exhibit potential in vitro antitumor activity. This journal is © The Royal Society of Chemistry 2012.

  3. Highly selective palladium–benzothiazole carbene-catalyzed allylation of active methylene compounds under neutral conditions

    Directory of Open Access Journals (Sweden)

    Antonio Monopoli

    2015-06-01

    Full Text Available The Pd–benzothiazol-2-ylidene complex I was found to be a chemoselective catalyst for the Tsuji–Trost allylation of active methylene compounds carried out under neutral conditions and using carbonates as allylating agents. The proposed protocol consists in a simplified procedure adopting an in situ prepared catalyst from Pd2dba3 and 3-methylbenzothiazolium salt V as precursors. A comparison of the performance of benzothiazole carbene with phosphanes and an analogous imidazolium carbene ligand is also proposed.

  4. Synthesis, antimicrobial and cytotoxic activities of pyrimidinyl benzoxazole, benzothiazole and benzimidazole.

    Science.gov (United States)

    Seenaiah, D; Reddy, P Ramachandra; Reddy, G Mallikarjuna; Padmaja, A; Padmavathi, V; Krishna, N Siva

    2014-04-22

    A variety of pyrimidinyl benzoxazoles, benzothiazoles and benzimidazoles linked by thio, methylthio and amino moieties were prepared and studied their antimicrobial and cytotoxic activities. The compound pyrimidinyl bis methylthio benzimidazole 22 was a potent antimicrobial agent particularly against Staphylococcus aureus (29 mm, MIC 12.5 μg/mL) and Penicillium chrysogenum (38 mm, MIC 12.5 μg/mL). The amino linked pyrimidinyl bis benzothiazole 24 exhibited cytotoxic activity on A549 cells with IC50 value of 10.5 μM.

  5. Hydroxylamine as an oxygen nucleophile: substitution of sulfonamide by a hydroxyl group in benzothiazole-2-sulfonamides

    NARCIS (Netherlands)

    Kamps, J.; Belle, R.; Mecinovic, J.

    2013-01-01

    Benzothiazole-2-sulfonamides react with an excess of hydroxylamine in aqueous solutions to form 2-hydroxybenzothiazole, sulfur dioxide, and the corresponding amine. Mechanistic studies that employ a combination of structure-reactivity relationships, oxygen labeling experiments, and (in)direct detect

  6. Triphenylamine based benzimidazole and benzothiazole: Synthesis and applications in fluorescent chemosensors and laser dyes

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yang [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China); University of Chinese Academy of Sciences, Beijing 100039 (China); Li, Bin, E-mail: libinteacher@163.com [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China); Zhang, Liming; Guan, Yunlong [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China)

    2014-01-15

    Triphenylamine based fluorescent dyes TPA-benzimidazole and TPA-benzothiazole have been designed and synthesized. The TPA-benzimidazole chemosensor was tested for a number of metal ions and found to exhibit binding affinity for Fe{sup 3+} and Hg{sup 2+} in acetonitrile, and the fluorescence quenching was achieved through a PET process. The appearance of an isosbestic point in absorption titrations and Job's plot analysis supported 1:1 stoichiometries for Fe{sup 3+} and Hg{sup 2+} ions. Laser experiments showed that under transversal pumping with a Q-switched Nd:YAG (355 nm) laser in toluene, TPA-benzothiazole exhibits efficient and stable amplified spontaneous emissions (ASE) at 436 nm. -- Highlights: • Triphenylamine based fluorescent dyes TPA-benzimidazole and TPA-benzothiazole have been designed and synthesized. • The TPA-benzimidazole exhibits binding affinity for Fe{sup 3+} and Hg{sup 2+} in acetonitrile and the fluorescence quenching was achieved through a PET process. • Under transversal pumping at 355 nm in toluene, TPA-benzothiazole exhibits efficient and stable amplified spontaneous emissions (ASE) in 436 nm.

  7. Comparative aquatic toxicity evaluation of 2-(thiocyanomethylthio)benzothiazole and selected degradation products using Ceriodaphnia dubia.

    Science.gov (United States)

    Nawrocki, S T; Drake, K D; Watson, C F; Foster, G D; Maier, K J

    2005-04-01

    2-(Thiocyanomethylthio)benzothiazole (TCMTB) is a biocide used in the leather, pulp and paper, and water-treatment industries. TCMTB may enter aquatic ecosystems during its manufacture and use. TCMTB is environmentally unstable; therefore, it is important to evaluate the toxicity of the more persistent degradation products. This study compared the toxicity of TCMTB with its degradation products 2-mercaptobenzothiazole (2-MBT), 2-(methylthio)benzothiazole (MTBT), benzothiazole (BT), and 2-hydroxybenzothiazole (HOBT). Toxicity was determined using Ceriodaphnia dubia 48-hour acute and 7-day chronic test protocols. TCMTB was the most toxic compound evaluated in both the acute and chronic tests with EC50s of 15.3 and 9.64 microg/L, respectively. 2-MBT, the first degradation product, was the second most toxic compound with acute and chronic EC50s of 4.19 and 1.25 mg/L, respectively. The toxicity of MTBT and HOBT were similar with acute EC50s of 12.7 and 15.1 mg/L and chronic EC50s of 6.36 and 8.31 mg/L, respectively. The least toxic compound was BT with acute and chronic EC50s of 24.6 and 54.9 mg/L, respectively. TCMTB was orders of magnitude more toxic than its degradation products. Toxicity data on these benzothiazole degradation products is important because of concerns regarding their release, degradation, persistence, and non-target organism effects in aquatic ecosystems. PMID:15750776

  8. N-[1-(2,5-Dimethyl-3-thienylethylidene]-1,3-benzothiazol-2-amine

    Directory of Open Access Journals (Sweden)

    Abdullah Mohamed Asiri

    2010-03-01

    Full Text Available The title compound, N-[1-(2,5-dimethyl-3-thienylethylidene]-1,3-benzothiazol-2-amine has been synthesized by condensation of 2-aminobenzothiazole and 3-acetyl-2,5-dimethylthiophene in ethanol. The structure of this new compound was confirmed by elemental analysis, IR, 1H-NMR, 13C-NMR and EI-MS spectral analysis.

  9. Microwave-assisted one-pot synthesis of benzothiazole and benzoxazole libraries as analgesic agents

    Indian Academy of Sciences (India)

    C Praveen; A Nandakumar; P Dheenkumar; D Muralidharan; P T Perumal

    2012-05-01

    Microwave-assisted synthesis of benzothiazole and benzoxazole libraries via PIFA promoted cyclocondensation of 2-aminothiophenols/2-aminophenols with aldehydes under one-pot condition in good to excellent yields was achieved. Twenty compounds have been investigated for their analgesic activity and showed moderate to good activity.

  10. The washout effect during laundry on benzothiazole, benzotriazole, quinoline, and their derivatives in clothing textiles.

    Science.gov (United States)

    Luongo, Giovanna; Avagyan, Rozanna; Hongyu, Ren; Östman, Conny

    2016-02-01

    In two previous papers, the authors have shown that benzothiazole, benzotriazole, quinoline, and several of their derivatives are widespread in clothing textile articles. A number of these compounds exhibit allergenic and irritating properties and, due to their octanol-water partition coefficient, are prone to be absorbed by the skin. Moreover, they are slightly soluble in water, which could make washing of clothes a route of emission into the environment. In the present study, the washout effect of benzothiazole, benzotriazole, quinoline, and some of their derivatives has been investigated. Twenty-seven textile samples were analyzed before, as well as after five and ten times of washing. The most abundant analyte was found to be benzothiazole, which was detected in 85 % of the samples with an average concentration of 0.53 μg/g (median 0.44 μg/g), followed by quinoline, detected in 81 % of the samples with an average concentration of 2.42 μg/g (median 0.21 μg/g). The average decrease in concentration for benzothiazoles was 50 % after ten times washing, while it was around 20 % for quinolines. The average emission to household wastewater of benzothiazoles and quinolines during one washing (5 kg of clothes made from polyester materials) was calculated to 0.5 and 0.24 g, respectively. These results strongly indicate that laundering of clothing textiles can be an important source of release of these compounds to household wastewater and in the end to aquatic environments. It also demonstrates a potential source of human exposure to these chemicals since considerable amounts of the compounds remain in the clothes even after ten times of washing.

  11. An analysis on the transmission of electron density through sulphur atoms in the quaternization reactions of benzothiazoles

    Indian Academy of Sciences (India)

    B K Mishra; Sabita Patel

    2002-02-01

    The kinetics of quaternization of a number of 2-substituted benzothiazoles with alkyl iodides and phenacyl bromide have been studied in nitrobenzene. The order of reactivity of different substituted benzothiazoles has been found to be -H > NO2 > Cl. The relative reactivity of 2-amino and 2-methyl derivatives has been ascribed to a solvation phenomenon. The analysis of rho values from the Hammett equation suggests two possible routes for the transmission of electron density.

  12. Synthesis and evaluation of 18F-fluoroethylated benzothiazole derivatives for in vivo imaging of amyloid plaques in Alzheimer's disease

    International Nuclear Information System (INIS)

    Amyloid aggregates play a major role in the development of Alzheimer's disease. Targeting these aggregates by PET probes enables non-invasively the detection and quantification of amyloid deposit distribution in human brains. Based on benzothiazole core structure a series of amyloid imaging agents were developed. Currently [11C]2-(4'-(methylamino)phenyl)-6-hydroxybenzothiazole (Pittsburgh Compound-B (PIB) is the most specific and widely used amyloid imaging ligand. But due to the short half life of 11C, longer lived 18F-labeled derivatives offer logistic advantages and higher contrast images. In this work, three different [18F]fluoroethoxy-substituted benzothiazole derivatives ([18F]2-(4'-(methylamino)phenyl)-6-(2-fluoroethoxy)benzothiazole, [18F]2-((2'-(2-fluoroethoxy)-4'-amino)phenyl)benzothiazole and [18F]2-(3'-((2-fluoroethoxy)-4'-amino)phenyl)benzothiazole) were synthesized via [18F]fluoroethylation. The latter two derivatives with fluoroethoxy-substitution on the aromatic amino group showed very low binding affinity for amyloid aggregates. In contrast [18F]2-(4'-(methylamino)phenyl)-6-(2-fluoroethoxy)benzothiazole with [18F]fluoroethoxy-substitution in 6-position showed excellent amyloid imaging properties with respect to lipophilicity, brain entry and brain clearance in normal SCID mice, amyloid plaque binding affinity and specificity.

  13. Oxidation of Refractory Benzothiazoles with PMS/CuFe2O4: Kinetics and Transformation Intermediates

    KAUST Repository

    Zhang, Tao

    2016-05-04

    Benzothiazole (BTH) and its derivatives, 2-(methylthio)bezothiazole (MTBT), 2-benzothiazolsulfonate (BTSA) and 2-hydroxybenzothiazole (OHBT), are refractory pollutants ubiquitously existing in urban runoff at relatively high concentrations. Here, we report their oxidation by CuFe2O4-activated peroxomonosulfate (PMS/CuFe2O4), focusing on kinetics and transformation intermediates. These benzothiazoles can be efficiently degraded by this oxidation process which is confirmed to generate mainly sulfate radicals (with negligible hydroxyl-radical formation) under slightly acidic to neutral pH conditions. The molar exposure ratio of sulfate radical to residual PMS (i.e. Rct) of this process is a constant which is related to reaction condition and can be easily determined. Reaction rate constants of these benzothiazoles towards sulfate radical are (3.3 ± 0.3) × 109, (1.4 ± 0.3) × 109, (1.5 ± 0.1) × 109 and (4.7 ± 0.5) × 109 M-1s-1, respectively (pH 7 and 20 oC). Based on Rct and these rate constants, their degradation in the presence of organic matter can be well predicted. A number of transformation products were detected and tentatively identified using triple-quadruple/linear ion trap MS/MS and high-resolution MS. It appears that sulfate radicals attack BTH, MTBT and BTSA on their benzo ring via electron transfer, generating multiple hydroxylated intermediates which are reactive towards common oxidants. For OHBT oxidation, it prefers to break down the thiazole ring. Due to competitions of the transformation intermediates, a minimum PMS/pollutant molar ratio of 10-20 is required for effective degradation. The flexible PMS/CuFe2O4 could be a useful process to remove the benzothiazoles from low DOC waters like urban runoff or polluted groundwater.

  14. 2-{[4-(1,3-Benzothiazol-2-ylphenyl](methylamino}acetic acid

    Directory of Open Access Journals (Sweden)

    Yong Zhang

    2009-11-01

    Full Text Available In the title compound, C16H14N2O2S, the dihedral angle between the benzothiazole ring system and benzene ring is 3.11 (2°. In the crystal structure, intermolecular O—H...N hydrogen bonds link molecules into chains along [100] and these chains are, in turn, linked into a three-dimensional network via weak intermolecular C—H...O hydrogen bonds.

  15. Oxidation of Refractory Benzothiazoles with PMS/CuFe2O4: Kinetics and Transformation Intermediates.

    Science.gov (United States)

    Zhang, Tao; Chen, Yin; Leiknes, TorOve

    2016-06-01

    Benzothiazole (BTH) and its derivatives 2-(methylthio)bezothiazole (MTBT), 2-benzothiazolsulfonate (BTSA), and 2-hydroxybenzothiazole (OHBT) are refractory pollutants ubiquitously existing in urban runoff at relatively high concentrations. Here, we report their oxidation by CuFe2O4-activated peroxomonosulfate (PMS/CuFe2O4), focusing on kinetics and transformation intermediates. These benzothiazoles can be efficiently degraded by this oxidation process, which is confirmed to generate mainly sulfate radicals (with negligible hydroxyl-radical formation) under slightly acidic to neutral pH conditions. The molar exposure ratio of sulfate radical to residual PMS (i.e., Rct) for this process is a constant that is related to the reaction condition and can be easily determined. The reaction rate constants of these benzothiazoles toward sulfate radical are (3.3 ± 0.3) × 10(9), (1.4 ± 0.3) × 10(9), (1.5 ± 0.1) × 10(9), and (4.7 ± 0.5) × 10(9) M(-1) s(-1), respectively (pH 7 and 20 °C). On the basis of Rct and these rate constants, their degradation in the presence of organic matter can be well-predicted. A number of transformation products were detected and tentatively identified using triple-quadruple/linear ion trap MS/MS and high-resolution MS. It appears that sulfate radicals attack BTH, MTBT, and BTSA on their benzo ring via electron transfer, generating multiple hydroxylated intermediates that are reactive toward common oxidants. For OHBT oxidation, the thiazole ring is preferentially broken down. Due to competitions of the transformation intermediates, a minimum PMS/pollutant molar ratio of 10-20 is required for effective degradation. The flexible PMS/CuFe2O4 could be a useful process to remove the benzothiazoles from low dissolved organic carbon waters like urban runoff or polluted groundwater. PMID:27144396

  16. Manganese(III) Acetate-Promoted Cross-Coupling Reaction of Benzothiazole/Thiazole Derivatives with Organophosphorus Compounds under Ball-Milling Conditions.

    Science.gov (United States)

    Li, Liang; Wang, Jun-Jie; Wang, Guan-Wu

    2016-07-01

    The first solvent-free manganese(III) acetate-promoted reaction of benzothiazole/thiazole derivatives with organophosphorus compounds including phosphine oxides, phosphinate ester, and phosphonate diester has been efficiently developed under ball-milling conditions, providing a highly efficient and green protocol to structurally diverse C2-phosphonylated benzothiazole/thiazole derivatives with remarkable functional group tolerance and excellent yields. PMID:27248000

  17. SYNTHESIS, CHARACTERIZATION AND BIOCIDAL ACTIVITY OF NOVEL HALOGENATED - 4-[(SUBSTITUTED-BENZOTHIAZOL-2-YL HYDRAZONO]-2-(SUBSTITUTED-PHENYL-5-METHYL /ETHOXY -2,4-DIHYDRO-PYRAZOL-3-ONE DERIVATIVES Synthese, Charakterisierung und biozide Aktivität NOVEL HALOGENIERTEN - 4 - [(substituiertes-benzothiazol-2-YL hydrazono] -2 -(Substituiertes Phenyl-5-Methyl / ETHOXY -2,4-DIHYDRO-pyrazol-3-ONE DERIVATE

    Directory of Open Access Journals (Sweden)

    V. Khatri, K. Sharma, V. Sareen, D. Shinde and S. Sareen

    2012-04-01

    Full Text Available Some new 4-[(substituted-benzothiazol-2-ylhydrazono]-2-(substituted-phenyl-5- methyl/ethoxy-2,4-dihydro-pyrazol-3-one(4 have been synthesized by reacting substituted 2- amino benzothiazol (1 with acetoacetic ester and malonic ester (2. 2-[(substituted-benzothiazol- 2-ylhydrazono]-3-oxo-butyric acid ethyl ester and 2-[(substituted-benzothiazol-2- ylhydrazono]- malonic acid diethyl ester (3 react with different hydrazines to give the title compounds(4. These compounds are evaluated for their antifungal and insecticidal activity. The structures of all these compounds have been confirmed by IR, 1H NMR, mass spectra and elemental analysis data.

  18. Determination of total sulfur compounds and benzothiazole in asphalt fume samples by gas chromatography with sulfur chemiluminescence detection.

    Science.gov (United States)

    Jaycox, L B; Olsen, L D

    2000-09-01

    As part of a collaborative project between the National Institute for Occupational Safety and Health and the Federal Highway Administration to evaluate asphalt pavers' exposures to asphalt fume and their potential health effects, a method was developed for the determination of total sulfur compounds and benzothiazole in asphalt fume samples. Asphalt fume samples were collected from asphalt mixtures with and without the addition of ground-up rubber tires. The asphalt fume samples were collected with sampling trains that consisted of a Teflon membrane filter and an XAD-2 adsorbent tube. Filter and sampling tube media were extracted with hexane and subsequently analyzed by gas chromatography with a sulfur chemiluminescence detector. Separation was achieved with a 100 percent dimethyl polysiloxane fused silica column. Typical calibration curves had linear correlation coefficients of 0.99 or better with a relative standard deviation (RSD) of 5 percent. Benzothiazole desorption efficiency (DE) determined using spiked sampling tubes ranged from 96.5 percent at 5.0 micrograms to 89.4 percent at 40 micrograms with RSD values from 0.9 to 4.0 percent. Benzothiazole storage recovery determined using sampling tubes spiked at 20 micrograms and refrigerated for 30 days at 4 degrees C was 89.8 percent when corrected for the DE with an RSD of 1.1 percent. The limit of detection for the method determined using spiked sampling tubes was 0.30 microgram. Quantitation for total sulfur compounds and benzothiazole was against benzothiazole standards in hexane. Because of detector selectivity, sample preparation consisted of a simple hexane extraction even when samples had a high background due to hydrocarbon overload. Detector sensitivity provided quantitation in the sub-microgram region. Because of the sample preparation step and because benzothiazole was determined during the same analysis run, this method is straightforward and analytically efficient. The method has been used to

  19. Occurrence, phase distribution, and mass loadings of benzothiazoles in riverine runoff of the Pearl River Delta, China.

    Science.gov (United States)

    Ni, Hong-Gang; Lu, Feng-Hui; Luo, Xian-lin; Tian, Hui-Yu; Zeng, Eddy Y

    2008-03-15

    A set of six benzothiazoles was determined in riverine runoff samples of the Pearl River Delta (PRD) collected monthly from March 2005 to February 2006. The concentrations of total benzothiazoles ranged from 220 to 611 ng/L, with benzothiazole (BT) being the most prominent (82%), followed by 2-methylthiobenzothiazole (MBT),thianaphthene (TN), and triphenylene (TP). The annual fluxes ofTN, BT, MBT, dibenzothiophene (DBT), 2-(4-morpholinyl)benzothiazole (24MoBT), and TP from the PRD to the coastal ocean were 1.94, 65.1, 10.1,0.63, 0.18, and 0.89 tons/yr, summing to yield an annual flux of 79 tons/yr for total benzothiazoles. In the PRD, approximately 1.1 x 10(5) tons of rubber are estimated to be released into the environment each year. This corresponds to the annual fluxes of 13 tons/yr for BT and 0.4 tons/yr for 24MoBT from tire particles. The annual fluxes of BT from scrap tires from Japan, Korea, Brazil, the European Union, the United States, and China were 99, 21, 36, 270, 328, and 120 tons/yr, respectively. The fluxes of 24MoBT from the same countries were 3.0, 0.5, 1.1, 8.4, 10.3, and 3.8 tons/ yr, respectively. These results indicated that tire-wear particles and scrap tires are the dominant sources of benzothiazoles in the environment. By comparison, Asia may be the major contributor to the global input of benzothiazoles from auto tires in the coming years. Overall, the six benzothiazoles under investigation appeared to be suitable tracers of pollutant inputs to surface runoff within the PRD aquatic system. In addition, 24MoBT seemed more appropriate than BT to trace tire rubber residues and therefore can be a good indicator of economic development and urbanization in a specific region. PMID:18409609

  20. Discovery and in vivo evaluation of alcohol-containing benzothiazoles as potent dual-targeting bacterial DNA supercoiling inhibitors.

    Science.gov (United States)

    Palmer, James T; Axford, Lorraine C; Barker, Stephanie; Bennett, James M; Blair, Michael; Collins, Ian; Davies, David T; Ford, Leigh; Gannon, Carlie T; Lancett, Paul; Logan, Alastair; Lunniss, Christopher J; Morton, Craig J; Offermann, Daniel A; Pitt, Gary R W; Rao, B Narasinga; Singh, Amit K; Shukla, Tarun; Srivastava, Anil; Stokes, Neil R; Thomaides-Brears, Helena B; Yadav, Anju; Haydon, David J

    2014-09-01

    A series of dual-targeting, alcohol-containing benzothiazoles has been identified with superior antibacterial activity and drug-like properties. Early lead benzothiazoles containing carboxylic acid moieties showed efficacy in a well-established in vivo model, but inferior drug-like properties demanded modifications of functionality capable of demonstrating superior efficacy. Eliminating the acid group in favor of hydrophilic alcohol moieties at C(5), as well as incorporating solubilizing groups at the C(7) position of the core ring provided potent, broad-spectrum Gram-positive antibacterial activity, lower protein binding, and markedly improved efficacy in vivo.

  1. N-(4-Chloro-1,3-benzothiazol-2-yl-2-(3-methylphenylacetamide monohydrate

    Directory of Open Access Journals (Sweden)

    H. S. Yathirajan

    2011-10-01

    Full Text Available In the title compound, C16H13ClN2OS·H2O, the dihedral angle between the mean planes of the benzothiazole ring system and the methylphenyl ring is 79.3 (6°. The crystal packing features intermolecular O—H...N, O—H...O and N—H...O hydrogen bonds involving the water molecule and weak C—H...O, C—H...Cg and π–π stacking interactions [centroid–centroid distances = 3.8743 (7, 3.7229 (7 and 3.7076 (8 Å].

  2. ASPECTS CONCERNING THE PHOTO- AND BIODEGRADATION OF BENZOTHIAZOLES IN AQUATIC COMPARTMENT

    Directory of Open Access Journals (Sweden)

    A.-M.Delort

    2008-12-01

    Full Text Available With the scope to provide complete decomposition of benzothiazoles in water environment, two approaches have been applied including the photocatalytic and biodegradation processes. A new type of continuous-action flow-through photocatalytic reactor was developed, in which it is possible to combine the homogeneous and heterogeneous destruction of refractory organic pollutants. The interactions between the different components of the aminobenzothiazole-containing system under the conditions of photo- and biodegradation (light, iron, free and immobilized bacterial strain Rhodococcus rhodochrous were analysed. The combined systems “Fe ± light +Rh.rhodochrous” are more effective than simple systems.

  3. Synthesis and mesomorphic evaluation of new calamitic liquid crystals containing benzothiazole core

    Institute of Scientific and Technical Information of China (English)

    Teck Ming Koh; Sie Tiong Ha; Teck Leong Lee; Siew Ling Lee; Guan Yeow Yeap; Hong Cheu Lin; Ramesh T. Subramaniam

    2011-01-01

    The design and synthesis of new calamitic benzothiazole-based liquid crystals, 2- [4-(4-alkyloxybenzoyloxy)-phenyI]ben-zothiazoles are presented. The target compound was characterized using spectroscopic techniques, such as FT-IR, NMR (1H and 13C), microanalysis and EI-MS. The liquid crystalline behaviours of these compounds were thoroughly examined by differential scanning calorimetry and polarizing optical microscope techniques. These materials exhibited enantiotropic nematic phase with high thermal stability (> 168℃). Smectic A phase starts to emerge as monotropic (metastable) phase from C10 member and changes into enantiotropic (stable) phase from C12 and persists up to C16 members.

  4. Colorimetric and fluorescence detection of G-quadruplex nucleic acids with a coumarin-benzothiazole probe.

    Science.gov (United States)

    Yan, Jin-wu; Tian, Yi-guang; Tan, Jia-heng; Huang, Zhi-shu

    2015-11-01

    A colorimetric and red-emitting fluorescent dual probe for G-quadruplexes was devised with a conjugated coumarin-benzothiazole scaffold. Its significant and distinct changes in both color and fluorescence enable the label-free and visual detection of G-quadruplex structures. In addition, this probe gives a distinct strong emission response to the nucleoli in fixed cells imaging, which might be attributed to the interaction between the probe and rDNA G-quadruplex based on the chromatin immunoprecipitation assay. All these results suggest its promising application prospects in the G-quadruplex research field.

  5. N-(4,6-Dimethylpyrimidin-2-yl-1,3-benzothiazol-2-amine

    Directory of Open Access Journals (Sweden)

    Shaaban K. Mohamed

    2011-11-01

    Full Text Available In the title compound, C13H12N4S, an amino N atom is connected to a 1,3-benzothiazole fused-ring system and a dimethyl-substituted pyrimidine ring, these components being aligned [interplanar dihedral angle = 1.9 (1°]. The secondary amino N atom forms an intermolecular N—H...N hydrogen bond to an N atom of the fused ring of an adjacent molecule, generating a centrosymmetric cyclic hydrogen-bonded dimer [graph set R22(8].

  6. New benzothiazole/thiazole-containing hydroxamic acids as potent histone deacetylase inhibitors and antitumor agents

    DEFF Research Database (Denmark)

    Thanh Tung, Truong; Oanh, Dao Thi Kim; Dung, Phan Thi Phuong;

    2013-01-01

    Results from clinical studies have demonstrated that inhibitors of histone deacetylase (HDAC) enzymes possess promise for the treatment of several types of cancer. Zolinza(®) (widely known as SAHA) has been approved by the FDA for the treatment of T-cell lymphoma. As a continuity of our ongoing...... research to find novel small molecules to target these important enzymes, we synthesized a series of benzothiazole-containing analogues of SAHA and found several compounds with very potent anticancer cytotoxicity. In this study, three more compounds of this type, including N(1)-(6-chlorobenzo[d]thiazol-2...

  7. Complex formation of 2-(o-hydroxyphenyl)-benzoxazole and 2-(o-hydroxyphenyl)-benzothiazole with beryllium ions

    Energy Technology Data Exchange (ETDEWEB)

    Gladilovich, D.B.; Stolyarov, K.P. (Leningradskij Gosudarstvennyj Univ. (USSR))

    1984-12-01

    Using spectrophotometric and luminescence methods the interaction of beryllium ions With 2-(0-hydroxyphenyl)-benzoxazole and 2-(0-hydroxyphenyl)-benzothiazole has been studied. The formation of at least three BeL/sup +/, Be(OH)L and BeL/sub 2/ complexes (where L=singly charged anion of ligand) is established.

  8. The Rearrangement of 2-Benzothiazolylthioacetyl Hydrazide in Synthesis of s-Triazolo[3,4-b]benzothiazole-3-thiol

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The rearrangement reaction of 2-benzothiazolylthioacetyl hydrazide 1 with potassium hydroxide and carbon disulfide in ethanol to produce s-triazolo[3,4-b]benzothiazole-3-thiol 3 was described.3 also can be obtained from 2-benzothiazolylhydazine 2 and the two methods for getting 3 were compared.Mannich reaction of compounds 3 was reported too.

  9. Transition metal-modified polyoxometalates supported on carbon as catalyst in 2-(methylthio)-benzothiazole sulfoxidation

    Indian Academy of Sciences (India)

    Romina A Frenzel; Gustavo P Romanelli; Mirta N Blanco; Luis R Piz

    2015-01-01

    Polyoxometalates with lacunary Keggin structure modified with transition metal ions [PW11O39M(H2O)]5−, where M = Ni2+, Co2+, Cu2+ or Zn2+, were synthesized and supported on activated carbon to obtain the PW11MC catalysts. Using FT-IR and DTA-TGA it was concluded that the [PW11O39M(H2O)]5− species are interacting with the functional groups of the support, and that thermal treatment leads to the loss of the coordinatively bonded water molecules without any noticeable anion degradation. The activity and selectivity of the catalysts in the sulfoxidation reaction of 2-(methylthio)-benzothiazole, an emerging environmental pollutant, were evaluated. The reaction was carried out in acetonitrile as solvent using H2O2 35% p/v as a clean oxidant. The conversion values decreased in the following order: PW11NiC > PW11CuC > PW11CoC > PW11ZnC, with selectivity to sulfoxide higher than 69%. The catalyst could be reused without appreciable loss of the catalytic activity at least three times. The materials were found to be efficient and recyclable catalysts for 2-(methylthio)-benzothiazole sulfoxidation in order to obtain a more biodegradable product than the corresponding substrate.

  10. Synthesis and in vivo diuretic activity of some new benzothiazole sulfonamides containing quinoxaline ring system.

    Science.gov (United States)

    Husain, Asif; Madhesia, Diwakar; Rashid, Mohd; Ahmad, Aftab; Khan, Shah Alam

    2016-12-01

    A series of new 6-substituted-N-[3-{2-(substituted phenyl)-ethenyl} quinoxaline-2(1H)-ylidene]-1,3-benzothiazole-2-amine (4a-f) were designed and synthesized by condensing 2-amino-benzothiazole-6-sulfonic acid amide (1) with chalcones of quinoxaline-2-one (3a-f) in a hope to obtain promising and a new class of diuretic agents. Structures of all the newly synthesized compounds were characterized by spectral data and elemental analysis. The pharmacological studies in experimental rats indicates that compound 4c possesses excellent in vivo diuretic activity of 1.13 and appears to be a better diuretic agent than the reference drugs, acetazolamide (1.0) and urea (0.88). Insight of the binding mode of the synthesized compounds (ligand) into the binding sites of carbonic anhydrase enzyme (PDF code: 4KUV) was provided by docking studies, performed with the help of Maestro 9.0 docking software. Further pharmacokinetic and toxicological studies are needed to confirm the safety of compound 4c which emerged as a lead diuretic compound.

  11. Synthesis, anti-breast cancer activity, and molecular modeling of some benzothiazole and benzoxazole derivatives.

    Science.gov (United States)

    Abdelgawad, Mohamed A; Belal, Amany; Omar, Hany A; Hegazy, Lamees; Rateb, Mostafa E

    2013-07-01

    A new series of benzothiazoles and benzoxazoles was synthesized using 4-benzothiazol-2-yl-phenylamine and 4-benzoxazol-2-yl-phenylamine as starting materials. All the prepared compounds were evaluated for their antitumor activities against human breast cancer cell lines, MCF-7 and MDA-231, using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability analysis. Almost all the tested compounds revealed potent antitumor activity, especially the N-methyl piperazinyl substituted derivatives 6f and 6c, which displayed the most potent inhibitory activity with IC50 values ranging from 8 to 17 nM. Docking the synthesized compounds into the epidermal growth factor receptor (EGFR), which is highly expressed in breast cancer, was employed to explore the possible interactions of these compounds with the EGFR. The activity of the reported compounds supports its clinical promise as a component of therapeutic strategies for cancer, for which high concentrations of chemotherapeutic agents are always a major limitation.

  12. Sorption of benzothiazoles onto sandy aquifer material under equilibrium and nonequlibrium conditions

    Directory of Open Access Journals (Sweden)

    Kragulj Marijana M.

    2014-01-01

    Full Text Available In this study, the sorption behaviour of 1,3-benzothiazole (BT and 2-(methylthiobenzothiazole (MTBT was investigated on Danube geosorbent under equilibrium and nonequilibrium conditions. All sorption isotherms fitted well with the Freundlich model (R2=0.932-0.993. The results showed that organic matter of the Danube geosorbent has a higher sorption affinity for the more hydrophobic MTBT compared to BT. However, sorption-desorption experiments showed that MTBT was more easily desorbed than BT molecules, which indicates the importance of absorption relative to adsorption in the overall sorption mechanism of MTBT. In general, molecules of BT and MTBT were more easily desorbed in the lower concentration range, which resulted in an increase in the hysteresis indices with increasing concentrations. Column experiments revealed that retention of the investigated compounds on the aquifer material followed the compound’s hydrophobicity. BT showed a lower retention, in accordance with its lower sorption affinity obtained in the static experiments, while MTBT showed a greater sorption affinity, and thus had a longer retention time on the column. Thus during transport BT represent greater risk for groundwaters than MTBT. These results have increased our understanding of benzothiazoles sorption and desorption process which represent one of the most important factors which influence the behaviour of organic compounds in the environment.

  13. Benzothiazole, benzotriazole, and their derivates in clothing textiles--a potential source of environmental pollutants and human exposure.

    Science.gov (United States)

    Avagyan, Rozanna; Luongo, Giovanna; Thorsén, Gunnar; Östman, Conny

    2015-04-01

    Textiles play an important role in our daily life, and textile production is one of the oldest industries. In the manufacturing chain from natural and/or synthetic fibers to the final clothing products, the use of many different chemicals is ubiquitous. A lot of research has focused on chemicals in textile wastewater, but the knowledge of the actual content of harmful chemicals in clothes sold on the retail market is limited. In this paper, we have focused on eight benzothiazole and benzotriazole derivatives, compounds rated as high production volume chemicals. Twenty-six clothing samples of various textile materials and colors manufactured in 14 different countries were analyzed in textile clothing using liquid chromatography tandem mass spectrometry. Among the investigated textile products, 11 clothes were for babies, toddlers, and children. Eight of the 11 compounds included in the investigation were detected in the textiles. Benzothiazole was present in 23 of 26 investigated garments in concentrations ranging from 0.45 to 51 μg/g textile. The garment with the highest concentration of benzothiazole contained a total amount of 8.3 mg of the chemical. The third highest concentration of benzothiazole (22 μg/g) was detected in a baby body made from "organic cotton" equipped with the "Nordic Ecolabel" ("Svanenmärkt"). It was also found that concentrations of benzothiazoles in general were much higher than those for benzotriazoles. This study implicates that clothing textiles can be a possible route for human exposure to harmful chemicals by skin contact, as well as being a potential source of environmental pollutants via laundering and release to household wastewater.

  14. Synthesis and evaluation of {sup 18}F-fluoroethylated benzothiazole derivatives for in vivo imaging of amyloid plaques in Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Neumaier, B. [Department of Nuclear Medicine, University of Ulm, Ulm (Germany); Max Planck Institute for Neurological Research, Klaus-Joachim-Zuelch Laboratories of the Max Planck Society and the Faculty of Medicine of the University of Cologne, Cologne (Germany)], E-mail: bernd.neumaier@nf.mpg.de; Deisenhofer, S. [Department of Nuclear Medicine, University of Ulm, Ulm (Germany); Sommer, C. [Department of Neuropathology, University of Mainz (Germany); Solbach, C.; Reske, S.N. [Department of Nuclear Medicine, University of Ulm, Ulm (Germany); Mottaghy, F. [Department of Nuclear Medicine, University of Ulm, Ulm (Germany); Department of Nuclear Medicine, RWTH Aachen, Aachen (Germany)

    2010-06-15

    Amyloid aggregates play a major role in the development of Alzheimer's disease. Targeting these aggregates by PET probes enables non-invasively the detection and quantification of amyloid deposit distribution in human brains. Based on benzothiazole core structure a series of amyloid imaging agents were developed. Currently [{sup 11}C]2-(4'-(methylamino)phenyl)-6-hydroxybenzothiazole (Pittsburgh Compound-B (PIB) is the most specific and widely used amyloid imaging ligand. But due to the short half life of {sup 11}C, longer lived {sup 18}F-labeled derivatives offer logistic advantages and higher contrast images. In this work, three different [{sup 18}F]fluoroethoxy-substituted benzothiazole derivatives ([{sup 18}F]2-(4'-(methylamino)phenyl)-6-(2-fluoroethoxy)benzothiazole, [{sup 18}F]2-((2'-(2-fluoroethoxy)-4'-amino)phenyl)benzothiazole and [{sup 18}F]2-(3'-((2-fluoroethoxy)-4'-amino)phenyl)benzothiazole) were synthesized via [{sup 18}F]fluoroethylation. The latter two derivatives with fluoroethoxy-substitution on the aromatic amino group showed very low binding affinity for amyloid aggregates. In contrast [{sup 18}F]2-(4'-(methylamino)phenyl)-6-(2-fluoroethoxy)benzothiazole with [{sup 18}F]fluoroethoxy-substitution in 6-position showed excellent amyloid imaging properties with respect to lipophilicity, brain entry and brain clearance in normal SCID mice, amyloid plaque binding affinity and specificity.

  15. Synthesis of benzothiazole derivatives%苯并噻唑类衍生物的合成

    Institute of Scientific and Technical Information of China (English)

    巨修练; 杨诗宏

    2013-01-01

    Heterocyclic compounds are becoming a research focus in drug development field with wide range of biological activity, low toxicity, high efficiency, environmental friendship and diverse structures. 5-chloro-2-benzoxazole ketone (chlorzoxazone) which is a nicotinic acetylcholine receptor antagonist was appliecl as a lead. The oxygen atom of the structure of 5-chloro-2-benzoxazole ketone was replaced by sulfur atom. Then a series of 5-chloro-2-benzothiazole derivatives were designed by the principle of bioisosterism and new structure of nicotinic acetylcholine receptor antagonists was developed. 5-chloro-2-benzothiazole ketones were synthesized by the reaction of 4-chloride-2-amino benzene mercaptan and urea, finally six phenylethanolamine benzothiazole derivatives were prepared followed by nucleophilic substitution with a series of halogenated hydrocarbon. All target compounds were characterized by 1HNMR, MS spectra. The biological activities of these compounds need further investigation.%由于杂环化合物具有广泛的生物活性,且具低毒、高效、对环境友好、结构多样化等多种优点,已成为当今药物开发的热点.以烟碱乙酰胆碱受体拮抗剂5-氯-2-苯并噁唑酮(商品名氯唑杀宗,chlorzoxazone)为先导,依据电子等排原理,将5-氯-2-苯并噁唑酮变换为以5-氯-2-苯并噻唑酮,设计了一系列5-氯-2-苯并噻唑酮衍生物,以期开发具有新型结构的烟碱乙酰胆碱受体拮抗剂.在合成方面,以4-氯-2-氨基苯硫醇为起始原料与脲素在酸性条件下闭环反应生成中间体5-氯-2-苯并噻唑酮,该中间体经重结晶纯化后,在碱性条件下,与一系列带有良好生物活性基团的卤代烃发生亲核取代,合成了六个未见文献报道的苯并噻唑衍生物,所有化合物均经过MS、[1H]NMR进行了结构表征,其生物活性有待研究.

  16. Synthesis and anticandidal evaluation of new benzothiazole derivatives with hydrazone moiety.

    Science.gov (United States)

    Yurttaş, Leyla; Kaplancıklı, Zafer Asım; Göger, Gamze; Demirci, Fatih

    2016-10-01

    In this study, we have performed the synthesis of new N'-(arylidene)-4-[(benzothiazol-2-yl)thio]butanoylhydrazide derivatives (3a-s) bearing azole moiety and hydrazone group in a lipophilic structural framework. The target compounds were prepared by a three step synthetic procedure starting from 2-mercaptobenzothiazole. The structures of the target compounds were elucidated by IR, (1)H NMR, (13)C NMR spectra and elemental analysis. The antifungal activity of the obtained compounds has been determined against a number of clinic and fluconazole-resistant Candida strains by using microdilution method. Compounds (3a-3s) exhibited anticandidal activity in different ratios varying between the range of MIC: 50 and 200 µg/mL. PMID:26247354

  17. Hybrid Moving Bed Biofilm Reactor for the biodegradation of benzotriazoles and hydroxy-benzothiazole in wastewater

    DEFF Research Database (Denmark)

    Mazioti, Aikaterini A.; Stasinakis, Athanasios S.; Psoma, Aikaterini K.;

    2016-01-01

    A laboratory scale Hybrid Moving Bed Biofilm Reactor (HMBBR) was used to study the removal of five benzotriazoles and one benzothiazole from municipal wastewater. The HMBBR system consisted of two serially connected fully aerated bioreactors that contained activated sludge (AS) and K3-biocarriers...... (CBTR) and 5-methyl-1H-benzotriazole (5TTR). Comparison of the HMBBR system with MBBR or AS systems from literature showed that the HMBBR system was more efficient for the biodegradation of the investigated chemicals. Biotransformation products of target compounds were identified using ultra high......-performance liquid chromatography, coupled with a quadrupole-time-of-flight high-resolution mass spectrometer (UHPLC-QToF-MS). Twenty two biotransformation products were tentatively identified, while retention time denoted the formation of more polar transformation products than the parent compounds....

  18. Design, synthesis, and structure-activity relationship studies of benzothiazole derivatives as antifungal agents.

    Science.gov (United States)

    Zhao, Shizhen; Zhao, Liyu; Zhang, Xiangqian; Liu, Chunchi; Hao, Chenzhou; Xie, Honglei; Sun, Bin; Zhao, Dongmei; Cheng, Maosheng

    2016-11-10

    A series of compounds with benzothiazole and amide-imidazole scaffolds were designed and synthesized to combat the increasing incidence of drug-resistant fungal infections. The antifungal activity of these compounds was evaluated in vitro, and their structure-activity relationships (SARs) were evaluated. The synthesized compounds showed excellent inhibitory activity against Candida albicans and Cryptococcus neoformans. The most potent compounds 14o, 14p, and 14r exhibited potent activity, with minimum inhibitory concentration (MIC) values in the range of 0.125-2 μg/mL. Preliminary mechanism studies revealed that the compound 14p might act by inhibiting the CYP51 of Candida albicans. The SARs and binding mode established in this study are useful for further lead optimization. PMID:27494168

  19. Design, Synthesis and Antiproliferative Activity of Novel Benzothiazole Derivatives Conjugated with Semicarbazone Scaffold.

    Science.gov (United States)

    Bao, Guanglong; Du, Baoquan; Ma, Yuxiu; Zhao, Meng; Gong, Ping; Zhai, Xin

    2016-01-01

    Two series of novel benzothiazole derivatives conjugated with semicarbazone scaffold were designed and synthesized through a structure-based molecular hybridization strategy. All the target compounds were evaluated for their cytotoxicity in vitro against three cancer cell lines (HT-29, MKN-45 and H460) by standard MTT assay. The pharmacological results indicated that seven compounds (17h-n) exhibited comparable or even better antiproliferative activity in comparison with reference drugs Sorafenib and PAC-1. Particularly, compound 17i displayed remarkable cytotoxicity against tested three cancer cell lines with IC50 values of 0.84, 0.06 and 0.52 µM, which were 4.3-, 36.6-, 4.2-folds more potent than Sorafenib and 1.2-, 13.7-, 6.9-times more active than PAC-1, respectively. PMID:26740207

  20. Multistep divergent synthesis of benzimidazole linked benzoxazole/benzothiazole via copper catalyzed domino annulation.

    Science.gov (United States)

    Liao, Jen-Yu; Selvaraju, Manikandan; Chen, Chih-Hau; Sun, Chung-Ming

    2013-04-21

    An efficient, facile synthesis of structurally diverse benzimidazole integrated benzoxazole and benzothiazoles has been developed. In a multi-step synthetic sequence, 4-fluoro-3-nitrobenzoic acid was converted into benzimidazole bis-heterocycles, via the intermediacy of benzimidazole linked ortho-chloro amines. The amphiphilic reactivity of this intermediate was designed to achieve the title compounds by the reaction of various acid chlorides and isothiocyanates in a single step through the in situ formation of ortho-chloro anilides and thioureas under microwave irradiation. A versatile one pot domino annulation reaction was developed to involve the reaction of benzimidazole linked ortho-chloro amines with acid chlorides and isothiocyanates. The initial acylation and urea formation followed by copper catalyzed intramolecular C-O and C-S cross coupling reactions furnished the angularly oriented bis-heterocycles which bear a close resemblance to the streptomyces antibiotic UK-1.

  1. Benzoxazole and benzothiazole amides as novel pharmacokinetic enhancers of HIV protease inhibitors.

    Science.gov (United States)

    Jonckers, Tim H M; Rouan, Marie-Claude; Haché, Geerwin; Schepens, Wim; Hallenberger, Sabine; Baumeister, Judith; Sasaki, Jennifer C

    2012-08-01

    A new class of benzoxazole and benzothiazole amide derivatives exhibiting potent CYP3A4 inhibiting properties was identified. Extensive lead optimization was aimed at improving the CYP3A4 inhibitory properties as well as overall ADME profile of these amide derivatives. This led to the identification of thiazol-5-ylmethyl (2S,3R)-4-(2-(ethyl(methyl)amino)-N-isobutylbenzo[d]oxazole-6-carboxamido)-3-hydroxy-1-phenylbutan-2-ylcarbamate (C1) as a lead candidate for this class. This compound together with structurally similar analogues demonstrated excellent 'boosting' properties when tested in dogs. These findings warrant further evaluation of their properties in an effort to identify valuable alternatives to Ritonavir as pharmacokinetic enhancers.

  2. 2-(2{prime}-hydroxyphenyl)benzothiazoles, -benzoxazoles, and -benzimidazoles for plastic scintillation applications

    Energy Technology Data Exchange (ETDEWEB)

    Pla-Dalmau, A. [Fermi National Accelerator Lab., Batavia, IL (United States)

    1995-08-25

    A new series of fluorescent compounds has been tested as dopants for plastic scintillation applications. Several 2-(2{prime}-hydroxyphenyl)benzothiazole, -benzoxazole, and -benzimidazole derivatives have been prepared and studied in a polystyrene matrix. Each derivative has been added to a styrene solution which has been thermally polymerized. The transmittance, fluorescence, and light yield characteristics of these compounds in polystyrene have been determined. Their emission time distributions have also been measured, and the decay time constants have been calculated from these data. In addition, the doped polystyrene samples have been irradiated to a total dose of 10 Mrad, utilizing a {sup 60}Co source in order to evaluate their susceptibility to radiation-induced damage. 6 figs., 1 tab.

  3. Antiwear and reducing friction performance of (2-sulphurone-benzothiazole)-3-methyl dodecanoate

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A heterocyclic derivative of (2-sulphurone-benzothiazole)-3-methyl dodecanoate was synthesized. Its tribological performance when added to liquid paraffin was evaluated on a four-ball tester and a ring-on-block machine. Results indicate that compared with the base oil the wear resistance and load-carrying capacities of the oil with novel additive are improved, and the friction coefficient is decreased. There is an optimal content of the novel compound, at which the corresponding oil gives the highest maximum non-seizure load. Above the content, the load carrying capacity of the oil is not increased but decreased. The nature of the film formed on the rubbed surface was investigated by X-ray photoelectron spectroscopy (XPS) analysis, and the action mechanism of the novel compound was discussed.

  4. Expeditious and Efficient Synthesis of Benzoxazoles, Benzothiazoles, Benzimidazoles Catalyzed by Ga(OTf)3 under Solvent-Free Conditions%Expeditious and Efficient Synthesis of Benzoxazoles, Benzothiazoles, Benzimidazoles Catalyzed by Ga(OTf)3 under Solvent-Free Conditions

    Institute of Scientific and Technical Information of China (English)

    刘巨艳; 刘倩; 徐玮; 王玮璐

    2011-01-01

    A new and efficient method for the synthesis of benzoxazoles, benzothiazoles, benzimidazoles from reactions of o-substituted aminoaromatics with orthoesters in the presence of catalytic amounts of Ga(OTf)3 under solvent-free conditions is presented. The remarkable features of this new protocol are high conversion, very short reaction times, cleaner reaction profiles under solvent-free conditions, straight forward procedure, and use of relatively non-toxic catalysts.

  5. Nanostructures and Self-Assembly of Organogels via Benzimidazole/Benzothiazole Imide Derivatives with Different Alkyl Substituent Chains

    Directory of Open Access Journals (Sweden)

    Xihai Shen

    2013-01-01

    Full Text Available New benzimidazole/benzothiazole imide derivatives with different alkyl substituent chains were designed and synthesized. Their gelation behaviors in 22 solvents were tested as novel low-molecular-mass organic gelators. The test showed that the alkyl substituent chains and headgroups of benzimidazole/benzothiazole residues in gelators played a crucial role in the gelation behavior of all compounds in various organic solvents. More alkyl chains in molecular skeletons in present gelators are favorable for the gelation of organic solvents. SEM and AFM observations revealed that the gelator molecules self-assemble into different aggregates from wrinkle, lamella and belt to dot with change of solvents. Spectral studies indicated that there existed different H-bond formation between imide groups and hydrophobic force of alkyl substituent chains in molecular skeletons. The present work may give some insights into design and character of new organogelators and soft materials with special molecular structures.

  6. Synthesis, photo-physical and DFT studies of ESIPT inspired novel 2-(2',4'-dihydroxyphenyl) benzimidazole, benzoxazole and benzothiazole.

    Science.gov (United States)

    Patil, Vikas S; Padalkar, Vikas S; Tathe, Abhinav B; Gupta, Vinod D; Sekar, N

    2013-09-01

    Novel ESIPT inspired benzimidazole, benzoxazole and benzothiazole were synthesized from 2,4-dihydroxy benzoic acid and 1,2-phenelenediamine, 2-aminophenol, and 2-aminothiophenol respectively. The synthesized 2-(2',4'-dihydroxyphenyl) benzimidazole, benzoxazole and benzothiazole are fluorescent and the emission characteristic are very sensitive to the micro-environment. They show a single absorption and dual emission with large Stokes shift originating from excited state intramolecular proton transfer. The absorption-emission characteristics of all these compounds are studied as a function of pH. The change in the electronic transition, energy levels, and orbital diagrams of synthesized compounds were investigated by the molecular orbital calculation and were correlated with the experimental spectral emission. Experimental absorption and emission wavelengths are in good agreement with those predicted using the Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TD-DFT) [B3LYP/6-31G(d)].

  7. Biodegradation of benzotriazoles and hydroxy-benzothiazole in wastewater by activated sludge and moving bed biofilm reactor systems

    OpenAIRE

    Mazioti, Aikaterini A.; Stasinakis, Athanasios S.; Pantazi, Ypapanti; Andersen, Henrik Rasmus

    2015-01-01

    Two laboratory scale fully aerated continuous flow wastewater treatment systems were used to compare the removal of five benzotriazoles and one benzothiazole by suspended and attached growth biomass. The Activated Sludge system was operated under low organic loading conditions. The Moving Bed Biofilm Reactor (MBBR) system consisted of two serially connected reactors filled with K3-biocarriers. It was either operated under low or high organic loading conditions. Target compounds were removed p...

  8. Water and ionic liquid synergy: A novel approach for the synthesis of benzothiazole-2(3H)-one

    OpenAIRE

    Malik A. Waseem; Shireen; Arjita Srivastava; Anjali Srivastava; Rahila; Siddiqui, I. R.

    2015-01-01

    Synergy between water, a green reaction medium and ionic liquid, a green catalyst has opened new vistas in the field of organic transformation. The developed methodology has emerged as an interesting combination for an environmentally benign, facile and efficient synthesis of benzothiazole-2(3H)-one. Product was achieved in excellent yield by the reaction of structurally diverse 2-iodoanilines with potassium thiocyanate. The strategy involves nucleophilic substitution forming NC and SC bond...

  9. 2-(Nitroaryl)benzothiazole and benzoxazole derivatives as fluorogenic substrates for the detection of nitroreductase activity in clinically important microorganisms.

    Science.gov (United States)

    Cellier, Marie; Gignoux, Amandine; James, Arthur L; Orenga, Sylvain; Perry, John D; Robinson, Shaun N; Stanforth, Stephen P; Turnbull, Graeme

    2015-12-15

    A series of carboxy-substituted 2-(nitroaryl)benzothiazole derivatives and carboxy-substituted 2-(nitroaryl)benzoxazole derivatives were prepared and evaluated as potential nitroreductase substrates for the purpose of detecting clinically important microorganisms. Several of the substrates produced highly fluorescent colonies with the majority of a panel of 10 Gram-negative bacteria and also with two of a panel of 8 Gram-positive bacteria.

  10. NaHSO4-SiO2-Promoted Solvent-Free Synthesis of Benzoxazoles, Benzimidazoles, and Benzothiazole Derivatives

    Directory of Open Access Journals (Sweden)

    K. Ravi Kumar

    2013-01-01

    Full Text Available An efficient protocol has been developed for the preparation of a library of benzoxazole, benzimidazole, and benzothiazole derivatives from reactions of acyl chlorides with o-substituted aminoaromatics in the presence of catalytic amount of silica-supported sodium hydrogen sulphate under solvent-free conditions. Simple workup procedure, high yield, easy availability, reusability, and use of ecofriendly catalyst are some of the striking features of the present protocol.

  11. Direct Preparation of 2-Benzothiazolylzinc Bromide and its Applications: A Facile Synthetic Route to the Preparation of 2-Substituted Benzothiazole Derivatives

    International Nuclear Information System (INIS)

    We have developed a novel approach for the direct preparation of 2-benzothiazolylzinc bromide and its application in organic synthesis. This protocol is a new tool for the convenient synthesis of 2-substituted benzothiazole derivatives. The resulting products obtained from this work can be utilized for further applications in the synthesis of many biologically active compounds. The benzothiazole moiety has been found in a variety of natural products and pharmaceuticals and demonstrates efficient biological activities. Specifically, 2-substituted benzothiazole derivatives have attracted considerable attention in a wide spectrum of chemical applications due to their unique structural properties. Therefore, the diversity of synthetic protocols has been an extensively discussed topic among scientists involved in organic synthesis for the past decades. In general, to build up the 2-substituted benzothiazole complexes, the strategic tools can be categorized as shown in Scheme 1: cross-coupling of benzothiazolylmetallic complexes (method A), coupling reaction of benzothiazole via direct oxidative C-H activation, cross-coupling of organometallic with halobenzothiazole, and ring-construction of N and S-containing compounds with the appropriate substrates

  12. Direct Preparation of 2-Benzothiazolylzinc Bromide and its Applications: A Facile Synthetic Route to the Preparation of 2-Substituted Benzothiazole Derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sooyoul [Korea Research Institute of Chemical Technology, Daejeon (Korea, Republic of); Lee, Kyuhyuk; Kim, Seunghoi [Dankook Univ., Yongin (Korea, Republic of)

    2014-06-15

    We have developed a novel approach for the direct preparation of 2-benzothiazolylzinc bromide and its application in organic synthesis. This protocol is a new tool for the convenient synthesis of 2-substituted benzothiazole derivatives. The resulting products obtained from this work can be utilized for further applications in the synthesis of many biologically active compounds. The benzothiazole moiety has been found in a variety of natural products and pharmaceuticals and demonstrates efficient biological activities. Specifically, 2-substituted benzothiazole derivatives have attracted considerable attention in a wide spectrum of chemical applications due to their unique structural properties. Therefore, the diversity of synthetic protocols has been an extensively discussed topic among scientists involved in organic synthesis for the past decades. In general, to build up the 2-substituted benzothiazole complexes, the strategic tools can be categorized as shown in Scheme 1: cross-coupling of benzothiazolylmetallic complexes (method A), coupling reaction of benzothiazole via direct oxidative C-H activation, cross-coupling of organometallic with halobenzothiazole, and ring-construction of N and S-containing compounds with the appropriate substrates.

  13. Determination of benzothiazole and benzotriazole derivates in tire and clothing textile samples by high performance liquid chromatography-electrospray ionization tandem mass spectrometry.

    Science.gov (United States)

    Avagyan, Rozanna; Sadiktsis, Ioannis; Thorsén, Gunnar; Östman, Conny; Westerholm, Roger

    2013-09-13

    A high performance liquid chromatography-tandem mass spectrometry method utilizing electrospray ionization in positive and negative mode has been developed for the separation and detection of benzothiazole and benzotriazole derivates. Ultra-sonication assisted solvent extraction of these compounds has also been developed and the overall method demonstrated on a selected clothing textile and an automobile tire sample. Matrix effects and extraction recoveries, as well as linearity and limits of detection have been evaluated. The calibration curves spanned over more than two orders of magnitude with coefficients of correlation R(2)>0.99 and the limits of detection and the limits of quantification were in the range 1.7-58pg injected and 18-140pg/g, respectively. The extraction recoveries ranged between 69% and 102% and the matrix effects between 75% and 101%. Benzothiazole and benzotriazole derivates were determined in the textile sample and benzothiazole derivatives determined in the tire sample with good analytical performance.

  14. Bis(2-amino-1,3-benzothiazole-κN3dichloridozinc(II ethanol hemisolvate

    Directory of Open Access Journals (Sweden)

    Young-Inn Kim

    2012-02-01

    Full Text Available In the title compound, [ZnCl2(C7H6N2S2]·0.5CH3CH2OH, the ZnII atom is coordinated by two N atoms of two 2-aminobenzothiazole ligands and two Cl atoms within a distorted tetrahedral geometry. The dihedral angle between the N/Zn/N and Cl/Zn/Cl planes is 86.22 (7°. The benzothiazole molecules are almost perpendicular to each other, forming a dihedral angle of 80.20 (8°. The molecular structure is stabilized by intramolecular N—H...Cl hydrogen bonds. In the crystal, intermolecular N—H...Cl hydrogen bonds link the molecules into a three-dimensional network. The SQUEEZE procedure in PLATON [Spek (2009. Acta Cryst. D65, 148–155] was used to model a disordered ethanol solvent molecule; the calculated unit-cell data allow for the presence of half of this molecule in the asymmetric unit.

  15. Improvement of the photo stabilization of PVC films in the presence of thioacetic acid benzothiazole complexes

    International Nuclear Information System (INIS)

    The photo stabilization of poly(vinyl chloride) (PVC) films by 2-thioacetic acid benzothiazole with Sn (II), Cd (II), Ni (II), Zn (II) and Cu (II) complexes was investigated. The PVC films containing concentration of complexes 0.5 % by weight were produced by the same casting method from tetrahydrofuran (THF) solvent. The photo stabilization activities of these compounds were determined by monitoring the carbonyl, polyene and hydroxyl indices with irradiation time. The changes in viscosity average molecular weight of PVC with irradiation time were also tracked (using THF as a solvent). The quantum yield of the chain scission (φcs) of these complexes in PVC films was evaluated and found to range between 4.71 x 10-8 and 8.98 x 10-8. Results obtained showed that the rate of photo stabilization of PVC in the presence of the additive follows the trend: Sn(L)2 > Cd(L)2 > Ni(L)2 > Zn(L)2 > Cu(L)2. According to the experimental results obtained, several mechanisms were suggested depending on the structure of the additive. Among them HCl scavenging, UV absorption, peroxide decomposer and radical scavenger for photo stabilizer additives mechanisms were suggested. (author)

  16. A QSAR study and molecular design of benzothiazole derivatives as potent anticancer agents

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A quantitative structure-activity relationship (QSAR) of a series of benzothiazole derivatives showing a potent and selective cytotoxicity against a tumorigenic cell line has been studied by using the density functional theory (DFT), molecular mechanics (MM+) and statistical methods, and the QSAR equation was established via a correlation analysis and a stepwise regression analysis. A new scheme determining outliers by "leave-one-out" (LOO) cross-validation coefficient (q2n-i) was suggested and successfully used. In the established optimal equation (excluding two outliers), the steric parameter (MRR) and the net charge (QFR) of the first atom of the substituent (R), as well as the square of hydrophobic parameter (lgP)2 of the whole molecule, are the main independent factors contributing to the anticancer activities of the compounds. The fitting correlation coefficient (R2) and the cross-validation coefficient (q2) values are 0.883 and 0.797, respectively. It indicates that this model has a significantly statistical quality and an excellent prediction ability. Based on the QSAR studies, 4 new compounds with high predicted anticancer activities have been theoretically designed and they are expected to be confirmed experimentally.

  17. Benzothiazoles in indoor air from Albany, New York, USA, and its implications for inhalation exposure.

    Science.gov (United States)

    Wan, Yanjian; Xue, Jingchuan; Kannan, Kurunthachalam

    2016-07-01

    Benzothiazole and its derivatives (collectively referred to BTHs) are used widely in many consumer (e.g., textiles) and industrial (e.g., rubber) products. Very little is known about the occurrence of BTHs in indoor air and the inhalation exposure of humans to these substances. In this study, 81 indoor air samples collected from various locations in Albany, New York, USA, in 2014 were analyzed for BTHs by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). BTHs were found in all indoor air samples, and the overall concentrations in bulk air (vapor plus particulate phases) were in the range of 4.36-2229ng/m(3) (geometric mean: 32.7ng/m(3)). The highest concentrations (geometric mean: 148ng/m(3)) were found in automobiles, followed by homes (49.5)>automobile garages (46.0)>public places, e.g., shopping malls (24.2)>barbershops (18.9) >offices (18.8)>laboratories (15.1). The estimated geometric mean daily intake (EDI) of BTHs for infants, toddlers, children, teenagers, and adults through indoor air inhalation from homes was 27.7, 26.3, 17.9, 10.5, and 7.77ng/kg-bw/day, respectively. The estimated contribution of indoor air to total BTHs intake was approximately 10%. This is the first study on the occurrence of BTHs in indoor air. PMID:26954474

  18. tert-Butyl N-[6-(N,N-dipropylcarbamoyl-1,3-benzothiazol-2-yl]carbamate

    Directory of Open Access Journals (Sweden)

    Xin Fang

    2010-05-01

    Full Text Available The title compound C19H27N3O3S, crystallizes with two unique molecules in the asymmetric unit. The benzene ring of each benzothiazole unit carries a dipropylcarbamoyl substituent in the 6-position and a tert-butyl carbamate unit on each thiazole ring. In the crystal structure, intermolecular N—H...N and weak C—H...O hydrogen bonds form centrosymmetric dimers. Additional C—H...O contacts construct a three-dimensional network. A very weak C—H...π contact is also present.

  19. Biodegradation of benzotriazoles and hydroxy-benzothiazole in wastewater by activated sludge and moving bed biofilm reactor systems

    DEFF Research Database (Denmark)

    Mazioti, Aikaterini A.; Stasinakis, Athanasios S.; Pantazi, Ypapanti;

    2015-01-01

    Two laboratory scale fully aerated continuous flow wastewater treatment systems were used to compare the removal of five benzotriazoles and one benzothiazole by suspended and attached growth biomass. The Activated Sludge system was operated under low organic loading conditions. The Moving Bed...... Biofilm Reactor (MBBR) system consisted of two serially connected reactors filled with K3-biocarriers. It was either operated under low or high organic loading conditions. Target compounds were removed partially and with different rates in tested systems. For MBBR, increased loading resulted...

  20. Identification of selected microorganisms from activated sludge capable of benzothiazole and benzotriazole transformation.

    Science.gov (United States)

    Kowalska, Katarzyna; Felis, Ewa

    2015-01-01

    Benzothiazole (BT) and benzotriazole (BTA) are present in the environment - especially in urban and industrial areas, usually as anthropogenic micropollutants. BT and BTA have been found in the municipal and industrial wastewater, rivers, soil, groundwater, sediments and sludge. The origins of those substances' presence in the environment are various industry branches (food, chemical, metallurgical, electrical), households and surface runoff from industrial areas. Increasingly strict regulations on water quality and the fact that the discussed compounds are poorly biodegradable, make them a serious problem in the environment. Considering this, it is important to look for environmentally friendly and socially acceptable ways to remove BT and BTA. The aim of this study was to identify microorganisms capable of BT and BTA transformation or/and degradation in aquatic environment. Selected microorganisms were isolated from activated sludge. The identification of microorganisms capable of BT and BTA removal was possible using molecular biology techniques (PCR, DNA sequencing). Among isolated microorganisms of activated sludge are bacteria potentially capable of BT and BTA biotransformation and/or removal. The most common bacteria capable of BT and BTA transformation were Rhodococcus sp., Enterobacter sp., Arthrobacter sp. They can grow in a medium with BT and BTA as the only carbon source. Microorganisms previously adapted to the presence of the studied substances at a concentration of 10 mg/l, showed a greater rate of growth of colonies on media than microorganisms unconditioned to the presence of such compounds. Results of the biodegradation test suggest that BT was degraded to a greater extent than BTA, 98-100% and 11-19%, respectively. PMID:26641641

  1. Separation of lanthanides and actinides(III) using tridentate benzimidazole, benzoxazole and benzothiazole ligands

    Energy Technology Data Exchange (ETDEWEB)

    Drew, M.G.B.; Hudson, M.J.; Iveson, P.B.; Vaillant, L.; Youngs, T.G.A. [Reading Univ. (United Kingdom). Dept. of Chemistry; Hill, C.; Madic, Ch. [CEA Valrho, Dir. de l' Energie Nucleaire, Departement RadioChimie et Procedes, Service de Chimie des Procedes de Separation (DEN/DRCP/SCPS/LCSE), 30 - Marcoule (France)

    2004-04-01

    The ability of new hydrophobic tridentate ligands based on 2,6-bis(benzimidazole-2-yl)pyridine, 2,6-bis(benzoxazole-2-yl)pyridine and 2,6-bis(benzothiazole-2-yl)pyridine to selectively extract americium(III) from europium(III) was measured. The most promising ligand - 2,6-bis(benzoxazole-2-yl)-4-(2-decyl-1-tetra-decyl-oxy)pyridine L{sup 9} was found to give separation factors (SF{sub Am/Eu}) of up to 70 when used to extract cations from 0.02-0.10 M HNO{sub 3} into TPH in synergy with 2-bromo-decanoic acid. Six structures of lanthanide complexes with 2,6-bis(benzoxazole-2-yl)pyridine L{sup 6} were then determined to evaluate the types of species that are likely to be involved in the separation process. Three structural types were observed, namely [LnL{sup 6}(NO{sub 3}){sub 3}(H{sub 2}O){sub 2}), 11-coordinate only for La, [LnL{sup 6}(NO{sub 3})3 (CH{sub 3}CN)], 10-coordinate for Pr, Nd and Eu and [LnL{sup 6}(NO{sub 3}){sub 3}(H{sub 2}O)], L 10-coordinate for Eu and Gd. Quantum Mechanics calculations were carried out on the tridentate ligands to elucidate the conformational preferences of the ligands in the free state and protonated and di-protonated forms and to assess the electronic properties of the ligands for comparison with other ter-dentate ligands used in lanthanide/actinide separation processes. (authors)

  2. White Organic Light-Emitting Devices Based on 2-(2-Hydroxyphenyl) Benzothiazole and Its Chelate Metal Complex

    Institute of Scientific and Technical Information of China (English)

    WU Xiao-Ming; HUA Yu-Lin; WANG Zhao-Qi; ZHENG Jia-Jin; FENG Xiu-Lan; SUN Yuan-Yuan

    2005-01-01

    @@ We present three kinds of organic light-emitting devices (OLED) fabricated to achieve the emission of bright and pure white light. Device A, with a double-layered structure using 2-(2-hydroxyphenyl) benzothiazole (HBT) and poly (N-vinylcarbazole) (PVK) as the emitting layer (EML) and the hole transport layer (HTL) respectively,could realize the blue-green light emission. Bis-(2-(2-hydroxyphenyl) benzothiazole)zinc (Zn(BTZ)2), synthesized with zinc acetate dihydrate and HBT to form a complex, is used as main EMLs in a similar structure to fabricate devices B and C. Bright and pure white light emissions can be obtained from device C which was fabricated with a green-white emitting host Zn(BTZ)2 and red dopant 5,6,11,12-tetraphenylnaphthacene (rubrene). The maximum quantum efficiency of device C could reach 0.63%, and the corresponding brightness and CIE coordinates were 4000cd/m2 and (x = 0.341, y = 0.334) at the driving voltage of 20 V.

  3. Corrosion inhibition efficiency and surface activity of benzothiazol-3-ium cationic Schiff base derivatives in hydrochloric acid

    Energy Technology Data Exchange (ETDEWEB)

    Negm, N.A., E-mail: nabelnegm@hotmail.co [Petrochemicals Department, Egyptian Petroleum Research Institute, Nasr City, Cairo (Egypt); Elkholy, Y.M.; Zahran, M.K. [Chemistry Department, Faculty of Science, Helwan University, Helwan (Egypt); Tawfik, S.M. [Petrochemicals Department, Egyptian Petroleum Research Institute, Nasr City, Cairo (Egypt)

    2010-10-15

    Research highlights: {yields} Benzothiazolium inhibitors show high corrosion inhibition for carbon steel. {yields} Weight loss and corrosion rates decrease by increasing inhibitor dose. {yields} Inhibition mechanism suggested as physisorption mechanism supported by adsorption free energy values. {yields} The adsorption of the inhibitors obeys Langmuir isotherm. {yields} Side chains have ascending order on the corrosion inhibition of the different inhibitors. - Abstract: Two series of cationic Schiff base surfactants namely: 2-(benzylideneamino)-3-(2-oxo-2-alkoxyethyl)-1,3-benzothiazol-3-ium bromide and 2-[(4-methoxybenzylidene)amino]-3-(2-oxo-2-alkoxyethyl)-1, 3-benzothiazol-3-ium bromide were prepared and confirmed using elemental analysis, FTIR, and {sup 1}H NMR spectra. The surface activity of the synthesized Schiff bases showed their tendency towards adsorption at the interfaces. The prepared compounds were evaluated as corrosion inhibitors for carbon steel in 0.5 M HCl solution using gravimetric and polarization measurements. By fitting the gravimetric data, some thermodynamic and kinetic parameters were estimated. The adsorption of the inhibitors on the carbon steel surface obeyed Langmuir adsorption isotherm and had a physical mechanism. Polarization measurements showed that the synthesized inhibitors act as mixed inhibitors for carbon steel in the acidic media. The results of the corrosion inhibition using two different methods showed narrow differences in the obtained values between the two methods within 5%.

  4. Determination of urinary 2-mercaptobenzothiazole (2-MBT), the main metabolite of 2-(thiocyanomethylthio)benzothiazole (TCMTB) in humans and rats.

    Science.gov (United States)

    Manninen, A; Auriola, S; Vartiainen, M; Liesivuori, J; Turunen, T; Pasanen, M

    1996-01-01

    A method for biological monitoring of urinary 2-(thiocyanomethylthio)benzothiazole (TCMTB), a wood preservative and an industrial chemical, was developed. Three different doses of TCMTB in olive oil were given to male rats by gavage for 3 weeks. Urine was collected daily and the metabolites were analysed as thioethers by derivatization with pentafluorobenzyl-bromide by gas chromatography-mass spectrometry. The parent chemical was not detected in urine samples, but two metabolites of TCMTB were identified. 2-Mercaptobenzothiazole (2-MBT) was the main metabolite, and its excretion varied according to the dose. The second metabolite was 2-(mercaptomethylthio)benzothiazole. The amount of 2-MBT excreted in rat urine was 66 +/- 12% (SD), 51 +/- 20% and 44 +/- 9% for TCMTB doses of 15, 75 and 150 mg/kg, respectively. Two doses, 75 and 150 mg/kg, caused diuresis in rats during the 1 week of dosing. During the 3-week TCMTB treatment, rat liver microsomal CYP enzyme profile was not significantly changed. Urine samples of sawmill workers exposed to TCMTB were collected after their work shifts for exposure assessment. TCMTB could not be detected in the urine samples of exposed workers. Most concentrations of 2-MBT were below the limit of the detection, 0.12 mumol/l, the concentrations were 0.12-0.15 mumol/l only in few cases. The determination of 2-MBT in urine, when a sample is taken immediately after a work shift, is a suitable indicator of workers' exposure to TCMTB. PMID:8831908

  5. Quantitative investigations of cation complexation of photochromic 8-benzothiazole-substituted benzopyran: towards metal-ion sensors.

    Science.gov (United States)

    Zakharova, Marianna I; Coudret, Christophe; Pimienta, Véronique; Micheau, Jean Claude; Delbaere, Stéphanie; Vermeersch, Gaston; Metelitsa, Anatoly V; Voloshin, Nikolai; Minkin, Vladimir I

    2010-02-01

    The photochromic, thermochromic and metallochromic behaviour of a series of three spiro[indoline-8-(benzothiazol-2-yl)-benzopyrans] has been investigated. The thermodynamic and kinetic parameters of their thermal equilibrium between the ring-closed (spiro) and ring-opened (merocyanine) isomeric forms have been determined using UV-Vis absorption and (1)H NMR spectroscopies. By adding Co(ii) and Ni(ii) ions in acetonitrile solution, 1 : 1 and 1 : 2 metal : merocyanine complexes are formed simultaneously. Using appropriate numerical methods, the kinetic analysis of the complexation allowed us to determine accurately key thermodynamic and spectroscopic parameters of the metal complexes. Results showed that the complexation strength is very sensitive to the size of the indoline nitrogen substituent. Complexation can be reversed by shining white light on the coloured complexes which regenerates the inactive spiropyran form, and releases the metallic ion; hence, these systems display fully reversible negative photochromism. The Zn(ii) complexes exhibit intense fluorescence in the 600-800 nm wavelength range. All these behaviours make these spiropyrans bearing benzothiazole heterocycles promising building blocks for the future construction of photodynamic chemosensors for transition metal ions. PMID:20126795

  6. Synthesis of new N-benzoxazole and N-benzothiazole derivatives of 3-(4-substituted phenyl) aminoisoxazol-5(2H)-ones and comparison of their base induced rearrangement

    Energy Technology Data Exchange (ETDEWEB)

    Khalafy, Jabbar; Marjani, Ahmad Poursattar; Ebrahimlo, Ali Reza Molla [Urmia University, Urmia (Iran, Islamic Republic of). Dept. of Chemistry]. E-mail: jkhalafi@yahoo.com

    2006-05-15

    3-Arylaminoisoxazol-5(2H)-ones, substituted on nitrogen with benzoxazole and benzothiazole groups react with triethylamine in ethanol under reflux to afford the corresponding indole and imidazobenzothiazole derivatives, respectively. (author)

  7. Comparative Studies on Conventional and Microwave Synthesis of Some Benzimidazole, Benzothiazole and Indole Derivatives and Testing on Inhibition of Hyaluronidase

    Directory of Open Access Journals (Sweden)

    Joachim Jose

    2008-03-01

    Full Text Available We have synthesized twelve 2-substituted benzimidazole, benzothiazole andindole derivatives using on both microwave irradiation and conventional heating methods.The microwave method was observed to be more beneficial as it provides an increase ofyield from 3% to 113% and a 95 to 98 % reduction in time. All compounds were tested bya stains-all assay at pH 7 and by a Morgan-Elson assay at pH 3.5 for hyaluronidaseinhibitory activity at a concentration of 100 μM. The most potent compound was 2-(4-hydroxyphenyl-3-phenylindole (12 with an IC50 value of 107 μM at both pH 7 and 3.5.

  8. Biodegradation of benzotriazoles and hydroxy-benzothiazole in wastewater by activated sludge and moving bed biofilm reactor systems.

    Science.gov (United States)

    Mazioti, Aikaterini A; Stasinakis, Athanasios S; Pantazi, Ypapanti; Andersen, Henrik R

    2015-09-01

    Two laboratory scale fully aerated continuous flow wastewater treatment systems were used to compare the removal of five benzotriazoles and one benzothiazole by suspended and attached growth biomass. The activated sludge system was operated under low organic loading conditions. The moving bed biofilm reactor (MBBR) system consisted of two serially connected reactors filled with K3-biocarriers. It was either operated under low or high organic loading conditions. Target compounds were removed partially and with different rates in tested systems. For MBBR, increased loading resulted in significantly lower biodegradation for 4 out of 6 examined compounds. Calculation of specific removal rates (normalized to biomass) revealed that attached biomass had higher biodegradation potential for target compounds comparing to suspended biomass. Clear differences in the biodegradation ability of attached biomass grown in different bioreactors of MBBR systems were also observed. Batch experiments showed that micropollutants biodegradation by both types of biomass is co-metabolic.

  9. Biodegradation of benzotriazoles and hydroxy-benzothiazole in wastewater by activated sludge and moving bed biofilm reactor systems.

    Science.gov (United States)

    Mazioti, Aikaterini A; Stasinakis, Athanasios S; Pantazi, Ypapanti; Andersen, Henrik R

    2015-09-01

    Two laboratory scale fully aerated continuous flow wastewater treatment systems were used to compare the removal of five benzotriazoles and one benzothiazole by suspended and attached growth biomass. The activated sludge system was operated under low organic loading conditions. The moving bed biofilm reactor (MBBR) system consisted of two serially connected reactors filled with K3-biocarriers. It was either operated under low or high organic loading conditions. Target compounds were removed partially and with different rates in tested systems. For MBBR, increased loading resulted in significantly lower biodegradation for 4 out of 6 examined compounds. Calculation of specific removal rates (normalized to biomass) revealed that attached biomass had higher biodegradation potential for target compounds comparing to suspended biomass. Clear differences in the biodegradation ability of attached biomass grown in different bioreactors of MBBR systems were also observed. Batch experiments showed that micropollutants biodegradation by both types of biomass is co-metabolic. PMID:26093257

  10. Water and ionic liquid synergy: A novel approach for the synthesis of benzothiazole-2(3H-one

    Directory of Open Access Journals (Sweden)

    Malik A. Waseem

    2015-05-01

    Full Text Available Synergy between water, a green reaction medium and ionic liquid, a green catalyst has opened new vistas in the field of organic transformation. The developed methodology has emerged as an interesting combination for an environmentally benign, facile and efficient synthesis of benzothiazole-2(3H-one. Product was achieved in excellent yield by the reaction of structurally diverse 2-iodoanilines with potassium thiocyanate. The strategy involves nucleophilic substitution forming NC and SC bonds resulting in the desired heterocyclic scaffold. This novel approach is also helpful for the synthesis of other related heterocycles for the development of an important drug like library. The reaction proceeded smoothly at an ambient temperature.

  11. Design and Synthesis of Novel Schiff Base-Benzothiazole Hybrids as Potential Epidermal Growth Factor Receptor (EGFR) Inhibitors.

    Science.gov (United States)

    Singh, Meenakshi; Singh, Sudhir Kumar; Thakur, Bhushan; Ray, Pritha; Singh, Sushil K

    2016-01-01

    A series of novel Schiff bases -benzothiazole hybrids was designed, synthesized and evaluated for their anticancer activity by MTT assay and western blot method. Antiproliferative screening indicated that compound containing dihydroxy substituents had potent inhibitory activity with IC50 value 34µg/ml against SKOV3, A2780-S and A2780-CR cell lines. It showed more potent cytotoxicity in combination with cisplatin and paclitaxel than alone in the selected cell lines (SKOV3, A2780 and A2780-CR models). The in vitro cytotoxicity of the compounds on IOSE 364 cell line was evaluated to establish the selectivity. Molecular docking study exhibited good binding against epidermal growth factor receptor, which was further ascertained by immunoblot assay using specific antibody against phosphorylated EGFR, and thus unravelling the targeted anticancer mechanism. PMID:26443027

  12. On the self-assembly of a highly selective benzothiazole-based TIM inhibitor in aqueous solution.

    Science.gov (United States)

    Hassan, Natalia; Gárate, M Pilar; Sandoval, Tania; Espinoza, Luis; Piñeiro, Ángel; Ruso, Juan M

    2010-11-16

    Benzothiazole is a common scaffold on which many bioactive structures, including protein inhibitors and biosensors, are based. The potential self-aggregation of such molecules to form nanoparticles is relevant for a number of practical applications. 3-(2-Benzothiazolylthio)-propanesulfonic acid (BTS) has been reported as a powerful and selective inhibitor of triosephosphate isomerase from Trypanosoma cruzi, the parasite that causes the Chagas' disease. Electrical conductivity, sound velocity, density, and nuclear magnetic resonance experiments as a function of temperature and of NaCl concentration have been performed in the present work to provide a comprehensive physicochemical description of this compound in aqueous solution. Molecular dynamics simulations of the same system were also performed to characterize the structure and dynamic behavior of the corresponding aggregates at several concentrations of BTS.

  13. Fast low-pressurized microwave-assisted extraction of benzotriazole, benzothiazole and benezenesulfonamide compounds from soil samples.

    Science.gov (United States)

    Speltini, Andrea; Sturini, Michela; Maraschi, Federica; Porta, Alessio; Profumo, Antonella

    2016-01-15

    Benzotriazoles (BTRs), benzothiazoles (BTs) and benzenesulfonamides (BSAs), compounds largely used in industrial and household applications, are ubiquitous emerging contaminants. In this work a novel, straightforward procedure for the simultaneous determination of two BTRs (1H-benzotriazole, 5-methyl-1H-benzotriazole), three BTs (benzothiazole, 2-hydroxybenzothiazole, 2-methylthiobenzothiazole) and two BSAs (benzenesulfonamide, toluenesulfonamide) in soil has been developed. The target analytes were extracted from soil by a single low-pressurized microwave-assisted extraction (MAE) cycle (120°C, 10min) and quantified by high-performance liquid chromatography with UV detection. For all the seven analytes, quantitative extraction yields (72-119%, n=4) were observed from recovery tests on soil samples (1g) spiked with 5, 10 and 50mg kg(-1), using 4mL water-methanol (85:15) as extracting solution. For the lower concentrations levels (100, 250 and 500μg kg(-1)), the analytes were extracted from soil samples (2-3g) using 6mL methanol, and the extract was pre-concentrated by evaporation before analysis; recoveries in the range 70-117% were obtained (n=4). Suitable intra-day and inter-day precision were observed, with values of relative standard deviation generally below 6% and 11% (n=4), respectively. Linearity was evaluated in the concentration range 0.5-10mg L(-1) by matrix-matched standards, obtaining r(2)>0.9996. The experimental method quantification limit (MQL) was 100μg kg(-1). The entire procedure has been successfully applied to the analysis of real impacted soil samples. PMID:26592614

  14. A p-Hydroxyphenacyl-Benzothiazole-Chlorambucil Conjugate as a Real-Time-Monitoring Drug-Delivery System Assisted by Excited-State Intramolecular Proton Transfer.

    Science.gov (United States)

    Barman, Shrabani; Mukhopadhyay, Sourav K; Biswas, Sandipan; Nandi, Surajit; Gangopadhyay, Moumita; Dey, Satyahari; Anoop, Anakuthil; Pradeep Singh, N D

    2016-03-18

    Among the well-known phototriggers, the p-hydroxyphenacyl (pHP) group has consistently enabled the very fast, efficient, and high-conversion release of active molecules. Despite this unique behavior, the pHP group has been ignored as a delivery agent, particularly in the area of theranostics, because of two major limitations: Its excitation wavelength is below 400 nm, and it is nonfluorescent. We have overcome these limitations by incorporating a 2-(2'-hydroxyphenyl)benzothiazole (HBT) appendage capable of rapid excited-state intramolecular proton transfer (ESIPT). The ESIPT effect also provided two unique advantages: It assisted the deprotonation of the pHP group for faster release, and it was accompanied by a distinct fluorescence color change upon photorelease. In vitro studies showed that the p-hydroxyphenacyl-benzothiazole-chlorambucil conjugate presents excellent properties, such as real-time monitoring, photoregulated drug delivery, and biocompatibility. PMID:26919455

  15. Anchoring of Cu(II) onto surface of porous metal-organic framework through post-synthesis modification for the synthesis of benzimidazoles and benzothiazoles

    Science.gov (United States)

    Kardanpour, Reihaneh; Tangestaninejad, Shahram; Mirkhani, Valiollah; Moghadam, Majid; Mohammadpoor-Baltork, Iraj; Zadehahmadi, Farnaz

    2016-03-01

    Efficient synthesis of various benzimidazoles and benzothiazoles under mild conditions catalyzed by Cu(II) anchored onto UiO-66-NH2 metal organic framework is reported. In this manner, first, the aminated UiO-66 was modified with thiophene-2-carbaldehyde and then the prepared Schiff base was reacted with CuCl2. The prepared catalyst was characterized by FT-IR, UV-vis, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), N2 adsorption, inductively coupled plasma atomic emission spectroscopy (ICP-AES) and field emission scanning electron microscopy (FE-SEM). The UiO-66-NH2-TC-Cu was applied as a highly efficient catalyst for synthesis of benzimidazole and benzothiazole derivatives by the reaction of aldehydes with 1,2-diaminobenzene or 2-aminothiophenol. The Cu(II)-containing MOF was reused several times without any appreciable loss of its efficiency.

  16. Evaluating the toxic potential of benzothiazoles with the rainbow trout cell lines, RTgill-W1 and RTL-W1.

    Science.gov (United States)

    Zeng, Fanxing; Sherry, James P; Bols, Niels C

    2016-07-01

    Benzothiazole (BTHs) are environmental contaminants of emerging concern for which little toxicological information is available. Therefore the toxic potential of twelve BTHs was evaluated with two rainbow trout epithelial cell lines, RTgill-W1 and RTL-W1. The BTHs were benzothiazole (BTH), 3,3'-diethylthia dicarbocyanine iodide (DTDC), C.I. sulphur orange 1 (SO), 2-mercaptobenzothiazole (2MBTH), zinc 2-mercaptobenzothiazole (ZnMBTH), sodium 2-mercaptobenzothiazole (NaMBTH), 2-hydroxy-benzothiazole (OHBTH), 2- aminobenzothiazole (2ABTH), C.I. vat yellow 2 (VY), N,N-dicyclohexyl-2-benzothiazolsulfene amide (NNA), 2,2'-dithiobis (benzothiazole) (DBTH) and 2-(p-aminophenyl)-6-methylbenzothiazole-7-sulfonic acid (MBTHS). All BTHs, except for NNA, DBTH, and MBTHS, caused both cytotoxicity and a transitory elevation in reactive oxygen species (ROS) levels. Yet, neither N-acetyl cysteine (NAC) nor IM-54 inhibited cytotoxicity, suggesting that ROS imbalance did not contribute to cell death. Cell death was not blocked by Necrostatin-1 nor accompanied by DNA laddering, suggesting that neither necroptosis nor apoptosis took place. The comet assay revealed DNA strand breaks after exposures to 2ABTH and OHBTH for 1 day and to BTH for 12 days. In RTL-W1, cytochrome P4501A was induced noticeably by 2ABTH, OHBTH, and MBTHS and weakly by NaMBTH, ZnMBTH, SO, VY, and NNA, suggesting that these BTHs have the potential to alter xenobiotic metabolism and activate the aryl hydrocarbon receptor. In summary, several toxic actions were initiated in vitro by some but not all BTHs, warranting further study of these BTHs in vivo. PMID:27131451

  17. SKLB-163, a new benzothiazole-2-thiol derivative, exhibits potent anticancer activity by affecting RhoGDI/JNK-1 signaling pathway

    OpenAIRE

    Peng, X; Xie, G; Z. Wang; H. Lin; Zhou, T.; Xiang, P.; Jiang, Y.(Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China; Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui, China; Department of Physics, Nanjing University, Nanjing, Jiangsu, China; School of Physics, Shandong University, Jinan, Shandong, China; Physics Department, Shanghai Jiao Tong University, Shanghai, China); Yang, S.; Wei, Y.; Yu, L.; Zhao, Y.

    2014-01-01

    Small-molecule inhibitors are an attractive therapeutic approach for most types of human cancers. SKLB-163, a novel benzothiazole-2-thiol derivative, was developed via computer-aided drug design and de novo synthesis. MTT assay showed it had potent anti-proliferative activity on various human cancer cells. Treatment of cancer cells with SKLB-163 induced obvious apoptosis and inhibited proliferation in vitro. SKLB-163 administered p.o. showed a marked antitumor activity in vivo. Proteomic tech...

  18. Application of the SOS/umu test and high-content in vitro micronucleus test to determine genotoxicity and cytotoxicity of nine benzothiazoles.

    Science.gov (United States)

    Ye, Yan; Weiwei, Jiang; Na, Li; Mei, Ma; Kaifeng, Rao; Zijian, Wang

    2014-12-01

    Benzothiazole and benzothiazole derivatives (BTs) have been detected in various environmental matrices as well as in human beings, but little is currently available regarding their toxicities. In our study, genotoxicities of nine BTs (benzothiazole [BT], 2-chlorobenzothiazole [CBT], 2-bromobenzothiazole [BrBT], 2-fluorobenzothiazole [FBT], 2-methylbenzothiazole [MeBT], 2-mercaptobenzothiazole [MBT], 2-aminobenzothiazole [ABT], 2-hydroxy-benzothiazole [OHBT] and 2-methythiobenzothiazole [MTBT]) are comprehensively evaluated by the SOS/umu test using the bacterial Salmonella typhimurium TA1535/pSK1002 for DNA-damaging effect and the high content in vitro micronucleus test using two human carcinoma cells (MGC-803 and A549) for chromosome-damaging effect. The cytotoxicity of BTs on both bacteria and two human cells was also evaluated. Except for the cytotoxic effect of MBT on MGC-803 and A549, the other tested BTs showed more than 50% cytotoxicity at their highest concentrations in a dose-dependent manner, and their LC50s ranged from 19 (MBT in bacteria) to 270 mg l(-1) (CBT in A549). Activation and inactivation were observed for specific BTs after metabolism. On the other hand, no evidence of genotoxicity was obtained for BT, FBT and MBT, and DNA damage was induced by ABT, OHBT, BrBT and MTBT in MGC-803, by MeBT in A549 and by CBT in both cells. Through quantitative structure-activity relationship analysis, two structure alerts for chemical genotoxicity, including heterocyclic amine and hacceptor-path3-hacceptor are present in ABT and OHBT respectively; however, the underlying mechanisms still need further evaluation.

  19. Rearrangement of 2-Benzothiazolylthioacetyl Hydrazide in Ethanol Solution of Potassium Hydroxide: Synthesis of s-Triazolo[3,4-b]benzothiazol-3-thiol and Its Derivatives

    Institute of Scientific and Technical Information of China (English)

    ZHANG,Yan(张艳); HUI,Xin-Ping(惠新平); DAI,Chao-Feng(戴朝峰); ZHANG,Zi-Yi(张自义); XU,Peng-Fei(许鹏飞)

    2002-01-01

    A novel rearrangement reaction about 2-benzothiazolylthioacetyl hydrazide (1) to produce s-triazolo[3,4-b]benzothiazol-3-thiol (3) in the presence of KOH and CS2 was described. Other way to synthesize 3 from 2-benzothiazolylhydrazine (2) under the same condition was compared and the Mannich reaction of compound 3 was reported too. Their structures were established by elemental analyses, IR, 1H NMR and MS spectra.

  20. In vitro DNA binding, pBR322 plasmid cleavage and molecular modeling study of chiral benzothiazole Schiff-base-valine Cu(II) and Zn(II) complexes to evaluate their enantiomeric biological disposition for molecular target DNA.

    Science.gov (United States)

    Alizadeh, Rahman; Afzal, Mohd; Arjmand, Farukh

    2014-10-15

    Bicyclic heterocyclic compounds viz. benzothiazoles are key components of deoxyribonucleic acid (DNA) molecules and participate directly in the encoding of genetic information. Benzothiazoles, therefore, represent a potent and selective class of antitumor compounds. The design and synthesis of chiral antitumor chemotherapeutic agents of Cu(II) and Zn(II), L- and -D benzothiazole Schiff base-valine complexes 1a &b and 2a &b, respectively were carried out and thoroughly characterized by spectroscopic and analytical techniques. Interaction of 1a and b and 2a and b with CT DNA by employing UV-vis, florescence, circular dichroic methods and cleavage studies of 1a with pBR322 plasmid, molecular docking were done in order to demonstrate their enantiomeric disposition toward the molecular drug target DNA. Interestingly, these studies unambiguously demonstrated the greater potency of L-enantiomer in comparison to D-enantiomer.

  1. In vitro DNA binding, pBR322 plasmid cleavage and molecular modeling study of chiral benzothiazole Schiff-base-valine Cu(II) and Zn(II) complexes to evaluate their enantiomeric biological disposition for molecular target DNA

    Science.gov (United States)

    Alizadeh, Rahman; Afzal, Mohd; Arjmand, Farukh

    2014-10-01

    Bicyclic heterocyclic compounds viz. benzothiazoles are key components of deoxyribonucleic acid (DNA) molecules and participate directly in the encoding of genetic information. Benzothiazoles, therefore, represent a potent and selective class of antitumor compounds. The design and synthesis of chiral antitumor chemotherapeutic agents of Cu(II) and Zn(II), L- and -D benzothiazole Schiff base-valine complexes 1a &b and 2a &b, respectively were carried out and thoroughly characterized by spectroscopic and analytical techniques. Interaction of 1a and b and 2a and b with CT DNA by employing UV-vis, florescence, circular dichroic methods and cleavage studies of 1a with pBR322 plasmid, molecular docking were done in order to demonstrate their enantiomeric disposition toward the molecular drug target DNA. Interestingly, these studies unambiguously demonstrated the greater potency of L-enantiomer in comparison to D-enantiomer.

  2. Synthesis and E/Z Configuration Determination of Novel Derivatives of 3-Aryl-2-(benzothiazol-2'-ylthio Acrylonitrile, 3-(Benzothiazol-2'-ylthio-4-(furan-2''-yl-3-buten-2-one and 2-(1-(Furan-2''-yl-3'-oxobut-1''-en-2-ylthio-3-phenylquinazolin-4(3H-one

    Directory of Open Access Journals (Sweden)

    Adel Abou El-Khair

    2011-07-01

    Full Text Available Knoevenagel condensation of 2-(benzothiazol-2-ylthio acetonitrile (2 with either furan-2-carbaldehyde or thiophene-2-carbaldehydes leads to E-isomers 4a–b exclusively, while the condensation of the compound 2 with benzaldehyde or para-substituted benzaldehydes with an electron-donating group afforded E/Z mixtures 4c–e with preferentially formation of the E-isomer. Condensation of furan-2-carbaldehyde (3a with either 1-(benzothiazol-2'-ylthio propan-2-one (5 or 2-(2'-oxo propylthio-3-phenyl-quinazolin-4(3H-one (9 leads exclusively to the Z-isomers of 6 and 10, respectively. The structures of the newly synthesized compounds were elucidated by elemental analyses, 1H-NMR and 13C-NMR spectra, COSY, HSQC, HMBC, NOE, MS and X-ray crystallographic investigations.

  3. Indirect extraction-spectrophotometric determination of 2-(thiocyanomethylthiol)benzothiazole in chrome tanning liquors after its breakdown to 2-mercaptobenzothiazole.

    Science.gov (United States)

    Hinojosa Reyes, Laura; Wróbel, Katarzyna; Wróbel, Kazimierz

    2002-03-01

    The simple extraction-spectrophotometric procedure is proposed in this work for the determination of 2-(thiocyanomethylthiol)benzothiazole (TCMTB) in chrome tanning liquors after its breakdown to 2-mercaptobenzothiazole (MBT). The sample (50mul) was 4-fold diluted with deionized water and the conversion of TCMTB to MBT was obtained with cysteine (400 mul, 0.1 moll(-1)) in alkaline conditions (pH 10). After acidification to pH 2.5 (100 mul phosphoric acid, 2 moll(-1)), the extraction was carried out with 800 mul of ethyl acetate, containing 0.2% of beta-mercaptoethanol and absorbance was measured at 324 nm with the cut-off filter 295 nm. To avoid possible errors due to MBT presence in the sample, this same sample was taken for blank, but the reagents were added in form of one acid solution (omitting the conversion step). The calibration range was 10-120 mugml(-1) of TCMTB with the regression coefficient 0.9999, the quantitation limit was 2.80 mugml(-1) and the within day precision was 3.34 and 0.20%, respectively, for 10 and for 100 mugml(-1) of TCMTB. The results obtained in the analysis of the three industrial liquor samples by the proposed procedure were in a good agreement with the results obtained using liquid chromatography method. PMID:18968524

  4. Third-Order Optical Nonlinearities of Squarylium Dyes with Benzothiazole Donor Groups Measured Using the Picosecond Z-Scan Technique

    International Nuclear Information System (INIS)

    Third-order optical nonlinearities of two squarylium dyes with benzothiazole donor groups (BSQ1 and BSQ2) in chloroform solution are measured by a picosecond Z-scan technique at 532 nm. It is found that the two compounds show the saturation absorption and nonlinear self-focus refraction effect. The molecular second hyperpolarizabilities are calculated to be 7.46 × 10−31 esu and 5.01 × 10−30 esu for BSQ1 and BSQ2, respectively. The large optical nonlinearities of squarylium dyes can be attributed to their rigid and intramolecular charge transfer structure. The difference in γ values is attributed to the chloro group of benzene rings of BSQ2 and the one-photon resonance effect. It is found that the third-order nonlinear susceptibilities of two squarylium dyes are mainly determined by the real parts of χ(3), and the large optical nonlinearities of studied squarylium dyes can be attributed to the nonlinear refraction. (fundamental areas of phenomenology(including applications))

  5. Synthesis and biological evaluation of benzothiazole derivatives bearing the ortho-hydroxy-N-acylhydrazone moiety as potent antitumor agents.

    Science.gov (United States)

    Ma, Junjie; Zhang, Guangyan; Han, Xiaoqi; Bao, Guanglong; Wang, Lihui; Zhai, Xin; Gong, Ping

    2014-12-01

    A novel series of benzothiazole derivatives bearing the ortho-hydroxy-N-acylhydrazone moiety were designed, synthesized, and evaluated for their procaspase-3 kinase activation activities and antiproliferative activities against five cancer cell lines (NCI-H226, SK-N-SH, HT29, MKN-45, and MDA-MB-231). Most target compounds showed moderate to excellent cytotoxic activity against all five tested cancer lines. The most promising compound 18e (procaspase-3 EC50  = 0.31 µM) with IC50 values ranging from 0.24 to 0.92µM against all tested cell lines was 4.24-12.2 times more active than PAC-1 (procaspase-3 EC50  = 0.41 µM). Structure-activity relationship studies indicated that the phenyl group on the 2-hydroxyphenyl ring (moiety A) was critical for pharmacological activity in vitro. In addition, introduction of a benzyloxyl group on moiety A and a mono-electron-withdrawing group at the 4-position of the benzyloxyl group were more favorable for antitumor activity. Moreover, reduction of the electron density in the phenyl ring of the benzyloxy group led to a dramatic decrease in the procaspase-3 kinase activation activity. PMID:25230149

  6. Pharmacophore modeling and 3D-QSAR studies on substituted benzothiazole / benzimidazole analogues as DHFR inhibitors with antimycobacterial activity

    Directory of Open Access Journals (Sweden)

    R. Priyadarsini

    2012-08-01

    Full Text Available The resurgence of tuberculosis and the emergence of multidrug-resistant strains of Mycobacteria drugs has propelled the development of new structural classes of antitubercular agents. The present study was undertaken to investigate the opportunities which the enzyme dihydrofolate reductase, a promising drug target for treatmentof Mycobacterial infections offers for the development of new TB drugs. Pharmacophore models were established by using the HipHop and HypoGen algorithms implemented in the Catalyst software package. Thebest quantitative pharmacophore model, consisted of two hydrogen bond acceptor, a hydrophobic aliphatic, and a ring aromatic feature which has the highest correlation coefficient (0.93, as well as enrichment factor of 1.75 and Goodness of hit score of 0.73. Based on the pharmacophore model some leads were optimized and some of its derivatives were synthesized and analysed by following QSAR studies. About 25 compounds of substituted benzothiazole/ benzimidazole derivatives were synthesized as potent DHFR inhibitors and screened for antimycobacterial activity. To further explore the structure-activity relationships of all newly synthesized compounds, 3D-QSAR analyses were developed. MFA studies were performed with the QSAR module of Cerius2 using genetic partial least squares (G/PLS algorithm. The predictive ability of the developed model was assessed using a training set of 25 and a test set of 5 compounds (r2pred = 0.924.The analyzed MF

  7. Novel Benzothiazole, Benzimidazole and Benzoxazole Derivatives as Potential Antitumor Agents: Synthesis and Preliminary in Vitro Biological Evaluation

    Directory of Open Access Journals (Sweden)

    Li Yang

    2012-01-01

    Full Text Available In a previous hit-to-lead research program targeting anticancer agents, two promising lead compounds, 1a and 1b, were found. However, the poor solubility of 1a and 1b made difficult further in vivo studies. To solve this problem, a lead optimization was conducted through introducing N-methyl-piperazine groups at the 2-position and 6-position. To our delight, the optimized analogue 1d showed comparable antiproliferative activity in vitro with better solubility, compared with 1a. Based on this result, the replacement of the benzothiazole scaffold with benzimidazole and benzoxazole moieties afforded 1f and 1g, whose activities were fundamentally retained. In the preliminary in vitro biological evaluation, the immunofluorescence staining of HCT116 cells indicated that 1d, 1f and 1g led to cytosolic vacuolization which was not induced by 1a at low micromolecular concentrations. These results suggest that these optimized compounds might potentially constitute a novel class of anticancer agents, which merit further studies.

  8. Novel benzothiazole, benzimidazole and benzoxazole derivatives as potential antitumor agents: synthesis and preliminary in vitro biological evaluation.

    Science.gov (United States)

    Xiang, Pu; Zhou, Tian; Wang, Liang; Sun, Chang-Yan; Hu, Jing; Zhao, Ying-Lan; Yang, Li

    2012-01-17

    In a previous hit-to-lead research program targeting anticancer agents, two promising lead compounds, 1a and 1b, were found. However, the poor solubility of 1a and 1b made difficult further in vivo studies. To solve this problem, a lead optimization was conducted through introducing N-methyl-piperazine groups at the 2-position and 6-position. To our delight, the optimized analogue 1d showed comparable antiproliferative activity in vitro with better solubility, compared with 1a. Based on this result, the replacement of the benzothiazole scaffold with benzimidazole and benzoxazole moieties afforded 1f and 1g, whose activities were fundamentally retained. In the preliminary in vitro biological evaluation, the immunofluorescence staining of HCT116 cells indicated that 1d, 1f and 1g led to cytosolic vacuolization which was not induced by 1a at low micromolecular concentrations. These results suggest that these optimized compounds might potentially constitute a novel class of anticancer agents, which merit further studies.

  9. Common benzothiazole and benzoxazole fluorescent DNA intercalators for studying Alzheimer Aβ1-42 and prion amyloid peptides.

    Science.gov (United States)

    Stefansson, Steingrimur; Adams, Daniel L; Tang, Cha-Mei

    2012-05-01

    Amyloids are fibrillar protein aggregates associated with a number of neurodegenerative pathologies including Alzheimer and Creutzfeldt-Jakob disease. The study of amyloids is usually based on fluorescence with the dye thioflavin-T. Although a number of amyloid binding compounds have been synthesized, many are nonfluorescent or not readily available for research use. Here we report on a class of commercial benzothiazole/benzoxazole containing fluorescent DNA intercalators from Invitrogen that possess the ability to bind amyloid Aβ1-42 peptide and hamster prion. These dyes fluoresce from 500-750 nm and are available as dimers or monomers. We demonstrate that these dyes can be used as acceptors for thioflavin-T fluorescence resonance energy transfer as well as reporter groups for binding studies with Congo red and chrysamine G. As more potential therapeutic compounds for these diseases are generated, there is a need for simple and inexpensive methods to monitor their interactions with amyloids. The fluorescent dyes reported here are readily available and can be used as tools for biochemical studies of amyloid structures and in vitro screening of potential therapeutics.

  10. Combined drug action of 2-phenylimidazo[2,1-b]benzothiazole derivatives on cancer cells according to their oncogenic molecular signatures.

    Directory of Open Access Journals (Sweden)

    Alessandro Furlan

    Full Text Available The development of targeted molecular therapies has provided remarkable advances into the treatment of human cancers. However, in most tumors the selective pressure triggered by anticancer agents encourages cancer cells to acquire resistance mechanisms. The generation of new rationally designed targeting agents acting on the oncogenic path(s at multiple levels is a promising approach for molecular therapies. 2-phenylimidazo[2,1-b]benzothiazole derivatives have been highlighted for their properties of targeting oncogenic Met receptor tyrosine kinase (RTK signaling. In this study, we evaluated the mechanism of action of one of the most active imidazo[2,1-b]benzothiazol-2-ylphenyl moiety-based agents, Triflorcas, on a panel of cancer cells with distinct features. We show that Triflorcas impairs in vitro and in vivo tumorigenesis of cancer cells carrying Met mutations. Moreover, Triflorcas hampers survival and anchorage-independent growth of cancer cells characterized by "RTK swapping" by interfering with PDGFRβ phosphorylation. A restrained effect of Triflorcas on metabolic genes correlates with the absence of major side effects in vivo. Mechanistically, in addition to targeting Met, Triflorcas alters phosphorylation levels of the PI3K-Akt pathway, mediating oncogenic dependency to Met, in addition to Retinoblastoma and nucleophosmin/B23, resulting in altered cell cycle progression and mitotic failure. Our findings show how the unusual binding plasticity of the Met active site towards structurally different inhibitors can be exploited to generate drugs able to target Met oncogenic dependency at distinct levels. Moreover, the disease-oriented NCI Anticancer Drug Screen revealed that Triflorcas elicits a unique profile of growth inhibitory-responses on cancer cell lines, indicating a novel mechanism of drug action. The anti-tumor activity elicited by 2-phenylimidazo[2,1-b]benzothiazole derivatives through combined inhibition of distinct effectors in

  11. Solvent-dependent excited-state hydrogen transfer and intersystem crossing in 2-(2′-hydroxyphenyl)-benzothiazole

    KAUST Repository

    Aly, Shawkat Mohammede

    2015-02-12

    The excited-state intramolecular hydrogen transfer (ESIHT) of 2-(2′-hydroxyphenyl) benzothiazole (HBT) has been investigated in a series of nonpolar, polar aprotic, and polar protic solvents. A variety of state-of-the-art experimental methods were employed, including femto- and nanosecond transient absorption and fluorescence upconversion spectroscopy with broadband capabilities. We show that the dynamics and mechanism of ESIHT of the singlet excited HBT are strongly solvent-dependent. In nonpolar solvents, the data demonstrate that HBT molecules adopt a closed form stabilized by O-H⋯N chelated hydrogen bonds with no twisting angle, and the photoinduced H transfer occurs within 120 fs, leading to the formation of a keto tautomer. In polar solvents, owing to dipole-dipole cross talk and hydrogen bonding interactions, the H transfer process is followed by ultrafast nonradiative deactivation channels, including ultrafast internal conversion (IC) and intersystem crossing (ISC). This is likely to be driven by the twisting motion around the C-C bond between the hydroxyphenyl and thiazole moieties, facilitating the IC back to the enol ground state or to the keto triplet state. In addition, our femtosecond time-resolved fluorescence experiments indicate, for the first time, that the lifetime of the enol form in ACN is approximately 280 fs. This observation indicates that the solvent plays a crucial role in breaking the H bond and deactivating the excited state of the HBT. Interestingly, the broadband transient absorption and fluorescence up-conversion data clearly demonstrate that the intermolecular proton transfer from the excited HBT to the DMSO solvent is about 190 fs, forming the HBT anion excited state.

  12. catena-Poly[bis(1,3-benzothiazol-3-ium [[dichloridoantimonate(III]-di-μ-chlorido-μ-oxido-[chloridoantimonate(III]-μ-chlorido

    Directory of Open Access Journals (Sweden)

    Oussama Chebout

    2016-02-01

    Full Text Available The title compound, {(C7H6NS2[Sb2Cl6O]}n, contains two benzothiazolidium cations and one tri-μ-chlorido-trichlorido-μ-oxido-diantimonate(III anion. The structure of the inorganic cation may be described as as being built up from two polyhedra, i.e. a square-pyramidal SbCl4O and a distorted octahedral SbOCl5 unit, sharing a common face (comprising the O atom and two Cl atoms. The two benzothiazole cations are quasi-planar and subtend a dihedral angle of 19.93 (5°. The crystal packing can be described by alternating (100 layers and [001] chains of the organic cations and inorganic anions connected through an extensive three-dimensional network of N—H...Cl, C—H...O and C—H...Cl hydrogen bonds. This is consolidated by slipped π–π stacking, with centroid-to-centroid distances between the benzothiazole rings of 3.7111 (18–3.8452 (16 Å. These interactions link the molecules within the layers and also link the layers together and reinforce the cohesion of the ionic structure.

  13. Inhibition of TNF-{alpha}-mediated inflammatory responses by a benzodioxolylacetylamino-linked benzothiazole analog in human fibroblast-like synoviocytes

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young-Rae [Department of Biochemistry, Research Institute for Endocrine Sciences and Diabetes Research Center, Chonbuk National University Medical School, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Jin, Guo Hua [College of Pharmacy, Sookmyung Women' s University, 52 Hyochangwon-gil, Yongsan-gu, Seoul 140-742 (Korea, Republic of); Lee, Sang-Myeong [Division of Biotechnology, College of Environmental and Bioresource Sciences, Chonbuk National University, Iksan, Jeonbuk 570-752 (Korea, Republic of); Park, Jin-Woo [Department of Biochemistry, Research Institute for Endocrine Sciences and Diabetes Research Center, Chonbuk National University Medical School, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Ryu, Jae-Ha [College of Pharmacy, Sookmyung Women' s University, 52 Hyochangwon-gil, Yongsan-gu, Seoul 140-742 (Korea, Republic of); Jeon, Raok, E-mail: rjeon@sm.ac.kr [College of Pharmacy, Sookmyung Women' s University, 52 Hyochangwon-gil, Yongsan-gu, Seoul 140-742 (Korea, Republic of); Park, Byung-Hyun, E-mail: bhpark@jbnu.ac.kr [Department of Biochemistry, Research Institute for Endocrine Sciences and Diabetes Research Center, Chonbuk National University Medical School, Jeonju, Jeonbuk 561-756 (Korea, Republic of)

    2011-05-20

    Highlights: {yields} We synthesized SPA0537, a benzothiazole analog. {yields} SPA0537 is a potent NF-{kappa}B inhibitor. {yields} SPA0537 suppresses the production of proinflammatory mediators in human rheumatoid fibroblast-like synoviocytes. {yields} SPA0537 is effective at suppressing osteoclast differentiation. -- Abstract: The pathologic processes of rheumatoid arthritis are mediated by a number of cytokines, chemokines, and matrix metalloproteinases, the expressions of which are controlled by NF-{kappa}B. This study was performed to explore the effects of a benzothiazole analog, SPA0537, on the control of the NF-{kappa}B activation pathway. We also investigated whether SPA0537 had any anti-inflammatory effects in human rheumatoid fibroblast-like synoviocytes (FLS). SPA0537 inhibited the nuclear translocation and the DNA binding of NF-{kappa}B subunits, which correlated with the inhibitory effects on IKK phosphorylation and I{kappa}B{alpha} degradation in TNF-{alpha}-stimulated rheumatoid FLS. These events further suppressed chemokine production, matrix metalloproteinase secretion, and TNF-{alpha}-induced cell proliferation. In addition, SPA0537 inhibited the osteoclast differentiation induced by macrophage colony-stimulating factor (MCSF) and receptor activator of the NF-{kappa}B ligand (RANKL) in bone marrow macrophages. These findings suggest that SPA0537 exerts anti-inflammatory effects in rheumatoid FLS through the inhibition of the NF-{kappa}B pathway. Therefore, it may have therapeutic value for the treatment of rheumatoid arthritis.

  14. Synthesis and biological evaluation of some 4-(6-substituted-1,3-benzothiazol-2-ylamino-1,3-thiazole-2-amines and their Schiff bases

    Directory of Open Access Journals (Sweden)

    Nikhil D. Amnerkar

    2015-07-01

    Full Text Available With the aim of obtaining newer biologically active compounds, a series of 4-(6-substituted-1,3-benzothiazol-2-ylamino-1,3-thiazole-2-amines (9–12 and 4-(6-substituted-1,3-benzothiazol-2-ylamino-2-(4-substitutedphenyl-methylideneamino-1,3-thiazole (13–28 were synthesized. The structures of all the synthesized compounds were confirmed by spectral (FTIR, 1H NMR and EI-MS data and elemental (C, H, N analysis. Furthermore, compounds (9–12 and (13–28 were screened for antibacterial, antifungal and anthelmintic activities. Almost all of these compounds showed moderate to excellent antimicrobial activity against two gram negative bacteria (Escherichia coli, Pseudomonas aeruginosa, two gram positive bacteria (Staphylococcus aureus, Bacillus subtilis, pathogenic fungal strains (Candida albicans, Aspergillus niger and good anthelmintic activity against earthworm species (Pontoscotex corethruses. Among the compounds tested, compounds 23 and 24 showed maximum activity against Gram negative and Gram positive bacteria, respectively. Compound 22 exhibited good antifungal activity while compound 26 displayed maximum anthelmintic activity comparable to the standard drugs.

  15. Synthesis of some novel phosphorylated and thiophosphorylated benzimidazoles and benzothiazoles and their evaluation for larvicidal potential to Aedes albopictus and Culex quinquefasciatus.

    Science.gov (United States)

    Bandyopadhyay, Prabal; Sathe, Manisha; Tikar, Sachin N; Yadav, Ruchi; Sharma, Pratibha; Kumar, Ashok; Kaushik, M P

    2014-07-01

    Series of benzimidazole and benzothiazole linked phosphoramidates and phosphoramidothioates (5a-j) and benzimidazole linked phenylphosphoramidates and phenylphosphoramidothioates (10a-e) were synthesized. The title compounds were preliminary screened for mosquito larvicidal properties against Aedes albopictus and Culex quinquefasciatus at different concentration from 40 to 5 mg/L. Among the screened compounds three compounds revealed potential larvicidal effects with 100% mortality in the order of 10e>5j>5e. Compound 10e was found to be the most toxic compound to Ae. albopictus and Cx. quinquefasciatus. The LC50 of 10e against Ae. albopictus was found to be 6.42 and 5.25 mg/L at 24 and 48 h, respectively, whereas it was 7.01 and 3.88 mg/L, respectively in Cx. quinquefasciatus. Temephos was used as positive control. PMID:24857290

  16. Synthesis and biological evaluation of a series of benzoxazole/benzothiazole-containing 2,3-dihydrobenzo[b][1,4]dioxine derivatives as potential antidepressants.

    Science.gov (United States)

    Wang, Songlin; Chen, Yin; Zhao, Song; Xu, Xiangqing; Liu, Xin; Liu, Bi-Feng; Zhang, Guisen

    2014-04-01

    A series of benzoxazole/benzothiazole-2,3-dihydrobenzo[b][1,4]dioxine derivatives (5a-5d and 8a-8j) was synthesized. Compounds were evaluated for binding affinities at the 5-HT1A and 5-HT2A receptors. Antidepressant activities of the compounds were screened using the forced swimming test (FST) and the tail suspension test (TST). The results indicated that the compounds exhibited high affinities for the 5-HT1A and 5-HT2A receptors and showed a marked antidepressant-like activity. Compound 8g exhibited high affinities for the 5-HT1A (Ki=17 nM) and 5-HT2A (Ki=0.71 nM) receptors; it also produced a decrease of the immobility time and exhibited potent antidepressant-like effects in the FST and TST in mice.

  17. Benzothiazoles with tunable electron-withdrawing strength and reverse polarity: a route to triphenylamine-based chromophores with enhanced two-photon absorption.

    Science.gov (United States)

    Hrobárik, Peter; Hrobáriková, Veronika; Sigmundová, Ivica; Zahradník, Pavol; Fakis, Mihalis; Polyzos, Ioannis; Persephonis, Peter

    2011-11-01

    A series of dipolar and octupolar triphenylamine-derived dyes containing a benzothiazole positioned in the matched or mismatched fashion have been designed and synthesized via palladium-catalyzed Sonogashira cross-coupling reactions. Linear and nonlinear optical properties of the designed molecules were tuned by an additional electron-withdrawing group (EWG) and by changing the relative positions of the donor and acceptor substituents on the heterocyclic ring. This allowed us to examine the effect of positional isomerism and extend the structure-property relationships useful in the engineering of novel heteroaromatic-based systems with enhanced two-photon absorption (TPA). The TPA cross-sections (δ(TPA)) in the target compounds dramatically increased with the branching of the triphenylamine core and with the strength of the auxiliary acceptor. In addition, a change from the commonly used polarity in push-pull benzothiazoles to a reverse one has been revealed as a particularly useful strategy (regioisomeric control) for enhancing TPA cross-sections and shifting the absorption and emission maxima to longer wavelengths. The maximum TPA cross-sections of the star-shaped three-branched triphenylamines are ∼500-2300 GM in the near-infrared region (740-810 nm); thereby the molecular weight normalized δ(TPA)/MW values of the best performing dyes within the series (2.0-2.4 GM·g(-1)·mol) are comparable to those of the most efficient TPA chromophores reported to date. The large TPA cross-sections combined with high emission quantum yields and large Stokes shifts make these compounds excellent candidates for various TPA applications, including two-photon fluorescence microscopy.

  18. Experimental and theoretical study of the structures and enthalpies of formation of 3H-1,3-benzoxazole-2-thione, 3H-1,3-benzothiazole-2-thione, and their tautomers.

    Science.gov (United States)

    Roux, Maria Victoria; Temprado, Manuel; Jiménez, Pilar; Foces-Foces, Concepción; Notario, Rafael; Parameswar, Archana R; Demchenko, Alexei V; Chickos, James S; Deakyne, Carol A; Liebman, Joel F

    2010-06-01

    This paper reports an experimental and theoretical study of the structures and standard (p(o) = 0.1 MPa) molar enthalpies of formation of 3H-1,3-benzoxazole-2-thione and 3H-1,3-benzothiazole-2-thione. The enthalpies of combustion and sublimation were measured by rotary bomb combustion calorimetry and the Knudsen effusion technique, and gas-phase enthalpies of formation values at T = 298.15 K of (42.0 +/- 2.7) and (205.5 +/- 3.8) kJ x mol(-1) for 3H-1,3-benzoxazole-2-thione and 3H-1,3-benzothiazole-2-thione, respectively, were determined. G3-calculated enthalpies of formation are in excellent agreement with the experimental values. The present work discusses the question of tautomerism explicitly for both compounds and compares the energetics of all the related species. A comparison of the theoretical results with the structural data is also reported.

  19. INFLUENCIA DE LA COMPOSICIÓN QUÍMICA SUPERFICIAL DEL CARBÓN ACTIVADO EN LA ADSORCIÓN DE BENZOTIAZOLES INFLUENCE OF ACTIVATED CARBON CHEMICAL SURFACE COMPOSITION ON THE ADSORPTION OF BENZOTHIAZOLES

    Directory of Open Access Journals (Sweden)

    Héctor Valdés

    2010-04-01

    Full Text Available Los benzotiazoles están esparcidos en el ambiente debido a su gran variedad de aplicaciones. Dentro de ellos, el benzotiazol (BT, el 2-hidroxibenzotiazol (OHBT, y el 2-metilbenzotiazol (MeBT son conocidos como agentes tóxicos y poco biodegradables. La adsorción con carbón activado se plantea como una opción atractiva para la remoción de estos contaminantes. Sin embargo, existen dudas acerca del efecto de las propiedades químicas superficiales del carbón activado sobre la capacidad de adsorción de estos compuestos. Para el estudio se utilizó carbón activado granular Filtrasorb-400 modificado con el objetivo de obtener carbones con diferentes propiedades químicas superficiales. Las series de carbones activados fueron obtenidas por pretratamiento por desoxigenación y por oxidación con ozono a diferentes tiempos de contacto. El incremento en la concentración de los grupos oxigenados superficiales produce una disminución en la capacidad de adsorción de los tres contaminantes ensayados. Los resultados sugieren que el mecanismo de adsorción transcurre principalmente a través de las interacciones de dispersión π-π entre los electrones del plano basal del carbón y el anillo aromático de los benzotiazoles. A valores de pH mayores al valor del pH de carga cero de la superficie del carbón activado (pH PZC, la capacidad de adsorción del carbón activado disminuye debido a la aparición de interacciones electrostáticas repulsivas entre los grupos superficiales oxigenados ionizados y las moléculas ionizadas de los benzotiazoles.Benzothiazoles, such as benzothiazole (BT, 2-hydroxybenzothiazole (OHBT, and 2-methylbenzothiazole (MeBT are toxic and poorly biodegradable organic compounds, frequently present in wastewater from rubber related applications. Activated carbon adsorption has been identified as an attractive treatment to removing those contaminants. This paper presents experimental results on the effect of chemical surface

  20. Design and synthesis of cis-restricted benzimidazole and benzothiazole mimics of combretastatin A-4 as antimitotic agents with apoptosis inducing ability.

    Science.gov (United States)

    Ashraf, Md; Shaik, Thokhir B; Malik, M Shaheer; Syed, Riyaz; Mallipeddi, Prema L; Vardhan, M V P S Vishnu; Kamal, Ahmed

    2016-09-15

    A series of colchicine site binding tubulin inhibitors were designed and synthesized by the modification of the combretastatin A-4 (CA4) pharmacophore. The ring B was replaced by the pharmacologically relevant benzimidazole or benzothiazole scaffolds, and the cis-configuration of the olefinic bond was restricted by the incorporation of a pyridine ring which is envisaged by the structural resemblance to a tubulin inhibitor like E7010. These compounds were evaluated for their antiproliferative activity on selected cancer cell lines and an insight in the structure activity relationship was developed. The most potent compounds (6c and 6l) demonstrated an antiproliferative effect comparable and superior to that of CA4 (GI50 up to 40nM). Mitotic cell cycle arrest in G2/M phase revealed the disruption of microtubule dynamics that was confirmed by tubulin polymerization assays and immunocytochemistry studies at the cellular level. The molecular docking studies suggested that the binding of these mimics at the colchicine site of the tubulin is similar to that of combretastatin A-4. PMID:27515320

  1. Synthesis of 2-(1-Benzofuran-2-yl-4-(1,3-benzoxazol-2-yl/ 1,3-benzothiazol-2-yl Quinolines as Blue Green Fluorescent Probes

    Directory of Open Access Journals (Sweden)

    Yadav D. Bodke

    2013-01-01

    Full Text Available A series of novel 2-(1-benzofuran-2-yl-4-(1,3 benzoxazol-2-yl/1,3-benzothiazol-2-yl quinoline derivatives 4(a–d were synthesized in one step by the reaction of 2-(1-benzofuran-2-yl quinoline-4-carboxylic acids 3(a-b with o-aminophenol and o-amino thiophenol, respectively, using polyphosphoric acid (PPA as a cyclizing agent. The fluorescent properties of newly synthesized compounds were investigated in three different organic solvents like chloroform (CHCl3, tetrahydrofuran (THF, and dimethyl sulfoxide (DMSO. The photophysical constants such as quantum yield and stokes shift were determined. From the results of fluorescence study, it is evident that all synthesized compounds are fluorescent in solution. Compound 4a emitted green light (490.4 nm, 518.2 nm, and 522.4 nm with high quantum yield in all the three solvents, while compounds 4b, 4c, and 4d emitted green light (512 nm, 499 nm, 510 nm only in polar solvent DMSO. All fluorescent probes exhibited a bathochromic shift on increase in polarity of the solvent.

  2. Design, synthesis, and structure-activity relationships of novel benzothiazole derivatives bearing the ortho-hydroxy N-carbamoylhydrazone moiety as potent antitumor agents.

    Science.gov (United States)

    Ma, Junjie; Chen, Dong; Lu, Kuan; Wang, Lihui; Han, Xiaoqi; Zhao, Yanfang; Gong, Ping

    2014-10-30

    A series of novel benzothiazole derivatives bearing the ortho-hydroxy N-carbamoylhydrazone moiety were designed and synthesized and their cytotoxic activities against five cancer cell lines (NCI-H226, SK-N-SH, HT29, MKN45, and MDA-MB-231) were screened in vitro. Most of them showed moderate to excellent activity against all the tested cell lines. Among them, compounds 15g (procaspase-3 EC50 = 1.42 μM) and 16b (procaspase-3 EC50 = 0.25 μM) exhibited excellent antitumor activity with IC50 values ranging from 0.14 μM to 0.98 μM against all cancer cell lines, which were 1.8-8.7 times more active than the first procaspase activating compound (PAC-1) (procaspase-3 EC50 = 4.08 μM). The structure-activity relationship (SAR) analyses indicated that the introduction of a lipophilic group (a benzyloxy or heteroaryloxy group) at the 4-position of the 2-hydroxy phenyl ring was beneficial to antitumor activity, and the presence of substituents containing nitrogen that are positively charged at physiological pH could also improve antitumor activity. It was also confirmed that the steric effect of the 4-position substituent of the benzyloxy group had a significant influence on cytotoxic activity. PMID:25171780

  3. A highly selective fluorescent 'turn-on' chemosensor for Zn(2+) based on a benzothiazole conjugate: their applicability in live cell imaging and use of the resultant complex as a secondary sensor of CN(-).

    Science.gov (United States)

    Khairnar, Nilesh; Tayade, Kundan; Sahoo, Suban K; Bondhopadhyay, Banashree; Basu, Anupam; Singh, Jasminder; Singh, Narinder; Gite, Vikas; Kuwar, Anil

    2015-02-01

    A benzothiazole derivative linked "off-on" multi-responsive and selective chemosensor has been synthesized and evaluated for cation recognition properties. The receptor shows a high sensitivity and selectivity for Zn(2+) through a 'turn-on' fluorescence response over the other tested cations with a detection limit as low as 0.67 μM. The receptor was successfully applied for the detection of Zn(2+) in live HeLa cells. Then, the Zn(2+) complex of receptor was also used for cyanide detection and recognition. PMID:25482915

  4. 一种苯并噻唑类稳定烯醇的合成及晶体结构%Synthesis and Crystal Structure of Stable Benzothiazole Enol

    Institute of Scientific and Technical Information of China (English)

    霍宝龙; 薛灵伟; 杨运旭; 杨超; 李大芝; 王爱志; 禹菲菲; 胡碧玮

    2014-01-01

    以2-甲基苯并噻唑和1,3-丙磺酸内酯为起始原料,合成了一种菁染料中间体2-(2-乙氧基-1-丁烯基)-1-(3-磺酸丙基)苯并噻唑(3).该染料中间体极易水解,对其水解产物(4e)采用红外光谱、核磁共振、质谱、元素分析和X射线单晶衍射分析等方法进行了表征. MS结果显示水解产物4e的分子量为327;在13 C NMR谱图中,烯醇结构中与羟基相连的碳的化学位移为194.05,与之相连的另一个双键碳的化学位移为δ92.52;在IR谱图中,1618 cm-1处存在烯醇的特征吸收峰;通过X射线单晶衍射分析测定了水解产物的结构,进一步证实该水解产物是一种存在共轭芳基结构的稳定烯醇.%As an important organic functional compound, 2-methylbenzothiazole derivatives has been widely used in sensitizing dyes. In the process of sythesis of dyes, the dye intermediates could be hydrolyzed to form another substance easily. In order to determine the structure of the new substance, a dye intermediate, named 2-(2-ethoxy-1-butenyl)-1-( 3-sulfopropyl ) benzothiazole ( 3 ) , was synthesized using 2-methyl benzothiazole and 1,3-propane sultone as the starting material, then hydrolyzed in water to form the new substance(4e), which was characterized by IR, 1 H NMR, 13 C NMR, MS, elemental analysis and X-ray diffraction methods. The MS spectrum showed the molecular weight of the product was 327 , which was corresponding to the target compound 4e. The 13 C NMR spectrum showed the chemical shift of the carbon that connected to the enol hy-droxyl group was δ194.05 , and the chemical shift of the carbon that connected to the double bond was 92.52, which implied the existence of enol structure. The IR spectrum also showed the enol hydroxyl charac-teristic absorption peak at 1618 cm-1 . X-Ray diffraction displayed the structure of the target compound intui-tively. Through the characterizations of the compound, the new substance was comfirmed to be a stable enol that

  5. Simultaneous determination of benzothiazoles, benzotriazoles and benzosulfonamides by solid phase microextraction-gas chromatography-triple quadrupole mass spectrometry in environmental aqueous matrices and human urine.

    Science.gov (United States)

    Naccarato, Attilio; Gionfriddo, Emanuela; Sindona, Giovanni; Tagarelli, Antonio

    2014-04-18

    This work proposes a new approach for the simultaneous determination of benzothiazoles, benzotriazoles and benzosulfonamides in different environmental matrices and human urine, using solid-phase microextraction coupled with gas-chromatography-triple quadrupole mass spectrometry (SPME-GC-QqQMS). The analytes object of this investigation have been classified as toxic to aquatic organisms and their presence in human urine was reported to occur as result of human exposure to contaminated environment. In this work many of the challenges related to the chemical diversity and polarity of the analytes selected were overcame conducting a multivariate optimization of the working conditions by using the approach of "Experimental design". Tests performed to assess the performances of five SPME coatings in direct immersion mode revealed the polyacrylate coating to be the most suitable for the extraction of the probe analytes. A central composite design (CCD) was employed to determine the optimal conditions for four factors affecting the solid-phase microextraction process: extraction time, extraction temperature, pH and percentage of sodium chloride. The optimal working condition determined by using Derringer's desirability function were 40min as extraction time, pH 7.1 and 6.0% of NaCl. Since the extraction temperature do not significantly affects the responses for all the analytes considered, analyses were performed at room temperature. A careful evaluation of the matrix effect for all the matrices tested was carried out. The results obtained showed that the proposed method did not significantly influenced by matrix effects in most of the cases tested, and thus allows the use of simplified calibration procedure. Satisfactory values of accuracy and precision were also obtained for all the matrices considered. PMID:24636758

  6. Highly efficient orange and red organic light-emitting diodes with iridium(III) complexes bearing benzothiazole cyclometallate ligands as emitters

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ming [College of Chemistry, Sichuan University, Chengdu, 610064 (China); Wang, Qi [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu, 610054 (China); Dai, Jun [College of Chemistry, Sichuan University, Chengdu, 610064 (China); Lu, Zhi-yun, E-mail: luzhiyun@scu.edu.cn [College of Chemistry, Sichuan University, Chengdu, 610064 (China); Huang, Yan [College of Chemistry, Sichuan University, Chengdu, 610064 (China); Yu, Jun-sheng, E-mail: jsyu@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu, 610054 (China); Luo, Shuai [College of Chemistry, Sichuan University, Chengdu, 610064 (China); Su, Shi-jian, E-mail: mssjsu@scut.edu.cn [State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices, South China University of Technology, Guangzhou, 510640 (China)

    2012-12-30

    Two iridium complexes bearing benzothiazole cyclometallate ligands, bis[2-(3 Prime ,5 Prime -di-tert-butylbiphenyl-4-yl)benzothiazolato-N,C{sup 2 Prime }]iridium(III) (acetylacetonate) [(tbpbt){sub 2}Ir(acac)] and bis[2-(9,9-dimethyl-9H-fluoren-2-yl)benzothiazolato-N,C{sup 2 Prime }]iridium(III) (acetylacetonate) [(fbt){sub 2}Ir(acac)], have been evaluated as orange and red electrophosphorescent materials. Both X-ray crystallographic analysis and photophysical results indicate that they possess alleviated self-quenching characteristics due to the existence of steric bulky ligands. As a result, phosphorescent organic light-emitting diodes (PhOLEDs) based on them show high performance even in heavily-doped level ({>=} 15 wt.%). The (tbpbt){sub 2}Ir(acac)-based PhOLED gives efficient orange emission with peak current efficiency of 26.9 cd/A (1280 cd/m{sup 2}) at doping ratio of 15 wt.%, while the 15 wt.% (fbt){sub 2}Ir(acac)-doped device emits efficient red light with Commission Internationale de l'Eclairage coordinates of (0.63, 0.36), and peak current and external quantum efficiency of 28.5 cd/A (1210 cd/m{sup 2}) and 15.6%, respectively. Moreover, all these heavily-doped PhOLEDs exhibit low efficiency roll-off at relatively high current density. - Highlights: Black-Right-Pointing-Pointer Two iridium complexes with bulky ligands are developed as orange/red emitter. Black-Right-Pointing-Pointer Organic light-emitting diodes using these phosphors show low efficiency roll-off. Black-Right-Pointing-Pointer High performance devices could be achieved under high doping ratio of {>=} 15 wt.%. Black-Right-Pointing-Pointer The high device efficiencies arise from the reduced self-quenching of the phosphors.

  7. Förster Resonance Energy Transfer (FRET) from Triton X-100 to 4-benzothiazol-2-yl-phenol: Varying FRET efficiency with CMC of the donor (Triton X-100)

    Energy Technology Data Exchange (ETDEWEB)

    Paul, Bijan Kumar, E-mail: bijan.paul.chem.cu@gmail.com [Department of Chemistry, University of Calcutta, 92 A.P.C. Road, Calcutta 700009 (India); Ganguly, Aniruddha [Department of Chemistry, University of Calcutta, 92 A.P.C. Road, Calcutta 700009 (India); Karmakar, Saswati [Department of Chemistry, Sree Chaitanya College, Habra, North 24 Parganas (India); Guchhait, Nikhil, E-mail: nguchhait@yahoo.com [Department of Chemistry, University of Calcutta, 92 A.P.C. Road, Calcutta 700009 (India)

    2013-11-15

    A heterocyclic compound viz., 4-benzothiazol-2-yl-phenol (4B2YP) has been synthesized and its photophysics have been examined through steady-state absorption, emission and time resolved emission spectroscopic techniques, in brief. Then 4B2YP has been exploited as an acceptor in the Förster Resonance Energy Transfer (FRET) process from photoexcited benzene aromatic nucleus of Triton X-100 (TX-100) surfactant. Dependence of the energy transfer efficiency on the donor concentration with respect to its critical micelle concentration (CMC) is clearly reflected in the study. High values of Stern–Volmer constant (K{sub SV}) for quenching of the donor fluorescence in the presence of the acceptor suggest the operation of long-range dipole–dipole interaction in the course of energy transfer process, while the inference is aptly supported from time resolved fluorescence decay results. Experimental results show maximum FRET efficiency at the CMC of the donor (TX-100). -- Highlights: • FRET from neutral surfactant Triton X-100 to chromophore 4-benzothiazol-2-yl-phenol. • Steady state and time resolved spectroscopy. • Long-range dipole–dipole interaction responsible for FRET. • FRET efficiency as a measure of CMC of surfactant.

  8. Synthesis, Antibacterial Activities and Nuclease Properties of Ternary Copper(II) Complex Containing 2-(2'-Pyridyl)benzothiazole and Glycinate%Synthesis, Antibacterial Activities and Nuclease Properties of Ternary Copper(II) Complex Containing 2-(2'-Pyridyl)benzothiazole and Glycinate

    Institute of Scientific and Technical Information of China (English)

    Lu, Yanmei; Chen, Yongheng; ou, Zhibin; Chen, Shi; Zhuang, Chuxiong; Le, Xueyi

    2012-01-01

    A new ternary complex [Cu(PBT)(Gly)(H2O)]ClO4 (PBT=2-(2'-pyridyl)benzothiazole, and Gly=glycinate) has been synthesized and characterized by elemental analysis, molar conductivity, and IR methods. The complex, structurally characterized by single-crystal X-ray crystallography, shows a slightly distorted square-pyramidal coordination geometry in which two nitrogen atoms of PBT and the carboxylate oxygen atom O and the amino nitrogen atom N of Gly bind at the basal plane, a water molecule is coordinated at the apical position. The complex, Cu(ClO4)2 and flee PBT were each tested for their ability to inhibit the growth of two Gram(--) (Escherichia coil, Salmonella) and two Gram(+) (Bacillus subtilis, Staphylococcus aureus) microorganisms. The complex showed good antibacterial activities against the microorganisms compared with free PBT and Cu(C104)2. The interaction between the complex and calf thymus DNA in aqueous solution was investigated using electronic spectroscopy, fluorescence spectroscopy, circular dichroic spectroscopy, and viscosity measurements. Results suggest that the complex could bind to DNA by an intercalative mode. In addition, the result of agarose gel electrophoresis showed that the complex can cleave the plasmid DNA by hydroxyl radicals and singlet oxygen-like species under the condition of physiological pH and room temperature.

  9. APPLICATION OF BENZOTHIAZOLE AND THEIR IODIDES IN DYE SENSITIZED SOLAR CELLS%苯并噻唑及其碘盐在染料敏化太阳电池中的应用

    Institute of Scientific and Technical Information of China (English)

    杨燕珍; 桃李; 吴玉程; 史成武; 张元元

    2012-01-01

    Influence of the heterocyclic structure and heteroatom N/S of additives, benzothiazole (BT) , 2-methyl benzothiazole (MBT), 3-methyl benzothiazolium iodide (MBTI) , 2,3-dimethyl benzothiazolium iodide (DMBTI) and 4-tert-butylpyridine (TBP), on I3-/I- redox behavior and the Pt electrode/solution interface reaction was in-vestigated by cyclic voltammetry using a Pt disk ultramicroelectrode and electrochemical impedance spectroscopy. The results revealed that the apparent diffusion coefficient of I3- and I- in solution decreased with additives being added. The charge transfer resistance at the Pt electrode I electrolyte interface increased by adding BT, MBT, TBP and decreased by adding MBTI, DMBT. From the photovoltaic performance of these DSCs, it was concluded that pyridine cycle was better than benzothiazole cycle and basic N atom was better than basic S atom in these additives.%分别以苯并噻唑(BT)、2-甲基苯并噻唑(MBT)、3-甲基苯并噻唑碘(MBTI)、2,3-二甲基苯并噻唑碘(DMBTI)及4-叔丁基吡啶(TBP)作为染料敏化太阳电池(DSCs)电解质溶液中的添加剂,使用超微电极通过循环伏安法和电化学阻抗谱研究上述5种添加剂的杂环结构及杂原子N和S对电解质中I3-和I-氧化还原行为和对铂黑电极|电解质界面的影响.结果表明,随着添加剂的加入,溶液中I3-和I-扩散系数均减小;添加BT、MBT和TBP,铂黑电极|电解质的界面传输电阻Rct增大,添加MBTI和DMBTI,Rct减小.电池的光伏性能测试结果表明,添加剂中含有吡啶环的结构优于苯并噻唑环,含有碱性N原子优于碱性S原子.

  10. Comparison of experimental and DFT-calculated NMR chemical shifts of 2-amino and 2-hydroxyl substituted phenyl benzimidazoles, benzoxazoles and benzothiazoles in four solvents using the IEF-PCM solvation model.

    Science.gov (United States)

    Pierens, Gregory K; Venkatachalam, T K; Reutens, David C

    2016-04-01

    A comparative study of experimental and calculated NMR chemical shifts of six compounds comprising 2-amino and 2-hydroxy phenyl benzoxazoles/benzothiazoles/benzimidazoles in four solvents is reported. The benzimidazoles showed interesting spectral characteristics, which are discussed. The proton and carbon chemical shifts were similar for all solvents. The largest chemical shift deviations were observed in benzene. The chemical shifts were calculated with density functional theory using a suite of four functionals and basis set combinations. The calculated chemical shifts revealed a good match to the experimentally observed values in most of the solvents. The mean absolute error was used as the primary metric. The use of an additional metric is suggested, which is based on the order of chemical shifts. The DP4 probability measures were also used to compare the experimental and calculated chemical shifts for each compound in the four solvents. Copyright © 2015 John Wiley & Sons, Ltd.

  11. Synthesis and Anti-inflammatory Activity of Novel Benzimidazole (Benzothiazole) Phenylursolate%新型熊果酸苯并咪(噻)唑连苯酯合成及抗炎活性测定

    Institute of Scientific and Technical Information of China (English)

    李财虎; 杨聪玲; 张宽; 石万棋; 李剑忠; 李颖; 尹述凡

    2012-01-01

    以熊果酸、取代苯甲醛和邻苯二胺或邻氨基苯硫酚为原料,合成了一系列熊果酸苯并咪(噻)唑连苯酯衍生物4a~4h,8个新化合物均未见文献报道,其结构经1H NMR,IR和HRMS加以确认,并对4a~4h进行药理活性筛选,结果表明,化合物4d (150 mg·kg-1),4g (150 mg·kg-1)等具有良好抗炎活性.%A novel series of the benzimidazole or benzothiazole phenyl ester derivatives of ursolic acid 4a~4h were prepared via ursolic acid, substituted benzaldehyde, and o-phenylendiamine or 2-aminothiophenol. The compounds were structurally confirmed by 'H NMR, 1R and HRMS techniques. The preliminary bioassay test demonstrated that compounds 4d and 4g had potent anti-inflammatory activity.

  12. Crystal structure of the salt bis(triethanolamine-κ4N,O,O′,O′′cadmium bis[2-(2-oxo-2,3-dihydro-1,3-benzothiazol-3-ylacetate

    Directory of Open Access Journals (Sweden)

    Jamshid Mengnorovich Ashurov

    2016-04-01

    Full Text Available The reaction of 2-(2-oxo-2,3-dihydro-1,3-benzothiazol-3-ylacetic acid (NBTA and triethanolamine (TEA with Cd(CH3OO2 resulted in the formation of the title salt, [Cd(C6H15NO32](C9H6NO3S2. In its crystal structure, the complex cation [Cd(TEA2]2+ and two independent NBTA− units with essentially similar geometries and conformations are present. In the complex cation, each TEA molecule behaves as an N,O,O′,O′′-tetradentate ligand, giving rise to an eight-coordinate CdII ion with a bicapped trigonal–prismatic configuration. All ethanol groups of each TEA molecule form three five-membered chelate rings around the CdII ion. The Cd—O and Cd—N distances are in the ranges 2.392 (2–2.478 (2 and 2.465 (2–2.475 (3 Å, respectively. O—H...O hydrogen bonds between the TEA hydroxy groups and carboxylate O atoms connect cationic and anionic moieties into chains parallel to [110]. Each NBTA− anion is additionally linked to a symmetry-related anion through π–π stacking interactions between the benzene and thiazoline rings [minimum centroid-to-centroid separation = 3.604 (2 Å]. Together with additional C—H...O interactions, these establish a double-layer polymeric network parallel to (001.

  13. New Conjugated Benzothiazole-N-oxides: Synthesis and Biological Activity

    Directory of Open Access Journals (Sweden)

    Pavlína Foltínová

    2009-12-01

    Full Text Available Eleven new 2-styrylbenzothiazole-N-oxides have been prepared by aldol – type condensation reactions between 2-methylbenzothiazole–N-oxide and para-substituted benzaldehydes. Compounds with cyclic amino substituents showed typical push-pull molecule properties. Four compounds were tested against various bacterial strains as well as the protozoan Euglena gracilis as model microorganisms. Unlike previously prepared analogous benzothiazolium salts, only weak activity was recorded.

  14. Homoleptic 2-mercapto benzothiazolate uranium and lanthanide complexes

    International Nuclear Information System (INIS)

    Treatment of [Ln(BH4)3(THF)3] (Ln = Ce, Nd) with 3 and 4 mol equiv of KSBT in tetrahydrofuran (THF) led to the formation of [Ln(SBT)3(THF)] and [K(THF)Ln(SBT)4], respectively. The uranium(IV) compound [U(SBT)4(THF)2] was obtained from U(BH4)4 and was reversibly reduced by sodium amalgam into the corresponding anionic uranium(III) complex. The crystal structures of [Ln(SBT)3(THF)2] (Ln = Ce, Nd), [K(15-crown-5)2][Nd(SBT)4], [U(SBT)4(THF)], and [K(15-crown-5)2][U(SBT)4(py)] show the bidentate coordination mode and the thionate character of the SBT ligand. (authors)

  15. 2-(1,3-Benzothiazol-2-yliminomethyl-2-naphthol

    Directory of Open Access Journals (Sweden)

    Khadija O. Badahdaha

    2009-04-01

    Full Text Available In the title molecule, C18H12N2OS, the dihedral angle between the two fused-ring systems is 7.2 (1°. The hydroxy group forms an intramolecular hydrogen bond with the imino group.

  16. Electrocatalytic oxidation of hydrazine on magnetic bar carbon paste electrode modified with benzothiazole and iron oxide nanoparticles:Simultaneous determination of hydrazine and phenol%苯并噻唑和铁氧化物纳米粒子修饰的磁性棒碳糊电极上肼的电催化氧化反应:同时检测肼和苯酚

    Institute of Scientific and Technical Information of China (English)

    Ali Benvidi; Shahriar Jahanbani; Bibi-Fatemeh Mirjalili; Reza Zare

    2016-01-01

    A magnetic bar carbon paste electrode (MBCPE) modified with Fe3O4 magnetic nanoparticles (Fe3O4NPs) and 2‐(3,4‐dihydroxyphenyl) benzothiazole (DPB) for the electrochemical determina‐tion of hydrazine was developed. The DPB was firstly self‐assembled on the Fe3O4NPs, and the re‐sulting Fe3O4NPs/DPB composite was then absorbed on the designed MBCPE. The MBCPE was used to attract the magnetic nanoparticles to the electrode surface. Owing to its high conductivity and large effective surface area, the novel electrode had a very large current response for the electrocat‐alytic oxidation of hydrazine. The modified electrode was characterized by voltammetry, scanning electron microscopy, electrochemical impedance spectroscopy, infrared spectroscopy, and UV‐visible spectroscopy. Voltammetric methods were used to study the electrochemical behaviour of hydrazine on MBCPE/Fe3O4NPs/DPB in phosphate buffer solution (pH = 7.0). The MBCPE/Fe3O4NPs/DPB, acting as an electrochemical sensor, exhibited very high electrocatalytic activity for the oxidation of hydrazine. The presence of DPB was found to reduce the oxidation potential of hydrazine and increase the catalytic current. The dependence of the electrocatalytic current on the hydrazine concentration exhibited two linear ranges, 0.1–0.4 µmol/L and 0.7–12.0 µmol/L, with a detection limit of 18.0 nmol/L. Additionally, the simultaneous determination of hydrazine and phe‐nol was investigated using the MBCPE/Fe3O4NPs/DPB electrode. Voltammetric experiments showed a linear range of 100–470 µmol/L and a detection limit of 24.3 µmol/L for phenol, and the proposed electrode was applied to the determination of hydrazine and phenol in water samples.%开发了一种磁性Fe3O4纳米粒子和2-(3,4-二羟苯基)苯并噻唑(DPB)修饰的磁性棒碳糊电极(MBCPE)用于电化学检测肼.首先将DPB自组装在Fe3O4纳米粒子上,然后将此复合物吸附于设计的MBCPE上. MBCPE电极将磁性纳米粒子

  17. {2-[(1,3-Benzothiazol-2-ylmethoxy]-5-fluorophenyl}(4-chlorophenylmethanone

    Directory of Open Access Journals (Sweden)

    K. N. Venugopala

    2013-07-01

    Full Text Available The asymmetric unit of the title compound, C21H13ClFNO2S, contains two independent molecules with similar conformations. In the molecules, the thiazole ring is essentially planar [maximum atomic deviations = 0.014 (4 and 0.023 (5 Å] and is oriented with respect to the fluorophenyl ring and chlorophenyl rings at 9.96 (18 and 70.39 (18° in one molecule and at 7.50 (18 and 68.43 (18° in the other; the dihedral angles between the fluorophenyl and chlorophenyl rings are 64.9 (2 and 64.6 (2°, respectively. Intermolecular C—H...O and C—H...F hydrogen bonds stabilize the three-dimensional supramolecular architecture. Weak C—H...π and π–π interactions [centroid–centroid distance = 3.877 (3 Å] lead to a criss-cross molecular packing along the c axis.

  18. Synthesis and Inhibition Effects on 5-HT{sub 6} Receptor of Benzothiazole Derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Hayat, Faisal; Yoo, Euna; Choo, Heayoung Park [Ewha Womans Univ., Seoul (Korea, Republic of); Rhim, Hyewhon [Korea Institute of Science and Technology, Seoul (Korea, Republic of)

    2013-02-15

    A novel series of aryl sulfonylpiperazine derivatives (5-15) were synthesized as 5-HT{sub 6} ligands. In vitro assay was evaluated by measuring the 5-HT-induced Ca{sup 2+} increases using HeLa cell line expressing the cloned human 5-HT{sub 6} receptor, and the compound 13 showed potent 5-HT{sub 6} receptor antagonistic effect with IC{sub 50} value of 3.9 μM. Compound 13 also showed good selectivity on the 5-HT{sub 6} over 5-HT{sub 4} and 5-HT{sub 7} receptors.

  19. 3-(4-Hexyloxyphenyl-1,2,4-triazolo[3,4-b]benzothiazole

    Directory of Open Access Journals (Sweden)

    Dieter Schollmeyer

    2014-03-01

    Full Text Available The title compound, C20H21N3OS, was prepared by Huisgen reaction of 5-(4-hexyloxyphenyltetrazole and chlorobenzothiazole. The essentially planar benzothiazolotriazole framework [maximum deviation from the mean plane of 0.077 (1 Å for the bridgehead N atom] and the phenyl ring form a dihedral angle of 53.34 (5°. The hexyloxy chain adopts a gauche–all-anti conformation. The intracentroid separation of 3.7258 (8 Å between the triazole and benzene rings is the closest contact between individual molecules in the crystal.

  20. A new hydroxynaphthyl benzothiazole derived fluorescent probe for highly selective and sensitive Cu(2+) detection.

    Science.gov (United States)

    Tang, Lijun; He, Ping; Zhong, Keli; Hou, Shuhua; Bian, Yanjiang

    2016-12-01

    A new reactive probe, 1-(benzo[d]thiazol-2-yl)naphthalen-2-yl-picolinate (BTNP), was designed and synthesized. BTNP acts as a highly selective probe to Cu(2+) in DMSO/H2O (7/3, v/v, Tris-HCl 10mM, pH=7.4) solution based on Cu(2+) catalyzed hydrolysis of the picolinate ester moiety in BTNP, which leads to the formation of an ESIPT active product with dual wavelength emission enhancement. The probe also possesses the advantages of simple synthesis, rapid response and high sensitivity. The pseudo-first-order reaction rate constant was calculated to be 0.205min(-1). Moreover, application of BTNP to Cu(2+) detection in living cells and real water samples was also explored. PMID:27391231

  1. Assessment of interactions between four proteins and benzothiazole derivatives by DSC and CD

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, Natalia [Soft Matter and Molecular Biophysics Group, Department of Applied Physics, Faculty of Physics, Campus Vida, University of Santiago de Compostela, E-15782 Santiago de Compostela (Spain); Verdes, Pedro V., E-mail: pedro.vazquez@usc.e [Soft Matter and Molecular Biophysics Group, Department of Applied Physics, Faculty of Physics, Campus Vida, University of Santiago de Compostela, E-15782 Santiago de Compostela (Spain); Ruso, Juan M. [Soft Matter and Molecular Biophysics Group, Department of Applied Physics, Faculty of Physics, Campus Vida, University of Santiago de Compostela, E-15782 Santiago de Compostela (Spain)

    2011-03-15

    The thermal denaturation of ovalbumin, lysozyme, myoglobin and fibrinogen at different BTS concentrations have been investigated using differential scanning calorimetry (DSC) and circular dichroism (CD) spectroscopy. Thermodynamic parameters: melting temperatures (T{sub m}), calorimetric enthalpy ({Delta}H), van't Hoff enthalpy ({Delta}H{sub v}) were obtained for all the systems under study. Thermal denaturation of the four proteins was completely irreversible. Changes in the protein conformation due to the adsorption of BTS molecules have been monitored by using UV-CD spectra. Greater changes in {alpha}-helical contents correspond with the BTS higher concentrations. The lysozyme denaturation temperature increases at low concentrations BTS indicating that BTS acts as a structure stabilizer; meanwhile it acts as a destabilizer at higher concentrations in all the proteins studied. The major effect is observed in the case of myoglobin, the protein with the highest {alpha}-helical secondary structure (75%).

  2. S8 -Mediated Cyclization of 2-Aminophenols/thiophenols with Arylmethyl Chloride: Approach to Benzoxazoles and Benzothiazoles.

    Science.gov (United States)

    Gan, Haifeng; Miao, Dazhuang; Pan, Qiang; Hu, Renhe; Li, Xiaotong; Han, Shiqing

    2016-06-21

    A metal-free approach to benzazoles from arylmethyl chlorides and 2-mercaptan/2-hydroxyanilines using elemental sulfur as a traceless oxidizing agent has been developed. The reactions proceeded in good to excellent yields, exhibiting good functional groups tolerance and gram-scale ability. A key mechanistic investigation indicated that the key intermediate trisulfide 6, which was characterized by NMR, HRMS and crystal X-ray crystallography, was separated in the reaction prior to the formation of the product.

  3. Bithiophene azo dyes bearing thiazole, benzothiazole and thiadiazole heterocycles : synthesis and comparative study of their photochromic properties

    OpenAIRE

    Castro, M. Cidália R.; Paulo J. Coelho; Fernandes, Sara S. M.; Fonseca, A. Maurício C.; Raposo, M. Manuela M.

    2012-01-01

    Although a large variety of diarylazo compounds are used in the design of optical materials, only a few reports concerning the photoisomerization of heterocyclic azo dyes can be found in the literature. In the last years our group reported for the first time the synthesis and characterization of heterocyclic azo dyes bearing thiophene and pyrrole moieties as thermally stable conducting materials, solvatochromic probes and nonlinear optical systems. The E/Z isomerizable N=N double bond within ...

  4. Chiral Separation of Novel a-Aminophosphonates Containing a Benzothiazole Moiety by Liquid Chromatography Using an Amylose Stationary Phase

    Institute of Scientific and Technical Information of China (English)

    LU Ping; ZHANG Yu-Ping; SONG Bao-An; YANG Song; BHADURY Shankar Pinaki; HU De-Yu; XUE Wei; CHEN Zhuo; JIN Lin-Hong

    2008-01-01

    The present report describes a chiral HPLC method for the enantiomeric separation of a-aminophosphonate derivatives using two new coated and immobilized amylose-based chiral stationary phases (CSP,Chiralpak IA and Chiralpak AD-H).The chromatographic parameters such as retention factor (k),separation factor (a),and resolution (Rs) of the solutes were investigated on these two CSPs.Reasonably good baseline separation for these compounds was achieved using Chiralpak IA column.The influences of temperature,content of ethanol modifier and the structure of analyte were also studied.THF,EtOAc and CH2Cl2 were used as ehients on analytical and semi-preparative columns.Highly enriched enantiomers with purities of up to 96.4%--100% (ee) and yields of 90.2%--95.5% were obtained,respectively.The proposed methods were found to be suitable and accurate for rapid separation and semi-preparation of enantiomeric a-aminophosphonate derivatives available.

  5. Benzothiazole Derivative as a Novel Mycobacterium tuberculosis Shikimate Kinase Inhibitor: Identification and Elucidation of Its Allosteric Mode of Inhibition.

    Science.gov (United States)

    Mehra, Rukmankesh; Rajput, Vikrant Singh; Gupta, Monika; Chib, Reena; Kumar, Amit; Wazir, Priya; Khan, Inshad Ali; Nargotra, Amit

    2016-05-23

    Mycobacterium tuberculosis shikimate kinase (Mtb-SK) is a key enzyme involved in the biosynthesis of aromatic amino acids through the shikimate pathway. Since it is proven to be essential for the survival of the microbe and is absent from mammals, it is a promising target for anti-TB drug discovery. In this study, a combined approach of in silico similarity search and pharmacophore building using already reported inhibitors was used to screen a procured library of 20,000 compounds of the commercially available ChemBridge database. From the in silico screening, 15 hits were identified, and these hits were evaluated in vitro for Mtb-SK enzyme inhibition. Two compounds presented significant enzyme inhibition with IC50 values of 10.69 ± 0.9 and 46.22 ± 1.2 μM. The best hit was then evaluated for the in vitro mode of inhibition where it came out to be an uncompetitive and noncompetitive inhibitor with respect to shikimate (SKM) and ATP, respectively, suggesting its binding at an allosteric site. Potential binding sites of Mtb-SK were identified which confirmed the presence of an allosteric binding pocket apart from the ATP and SKM binding sites. The docking simulations were performed at this pocket in order to find the mode of binding of the best hit in the presence of substrates and the products of the enzymatic reaction. Molecular dynamics (MD) simulations elucidated the probability of inhibitor binding at the allosteric site in the presence of ADP and shikimate-3-phosphate (S-3-P), that is, after the formation of products of the reaction. The inhibitor binding may prevent the release of the product from Mtb-SK, thereby inhibiting its activity. The binding stability and the key residue interactions of the inhibitor to this product complex were also revealed by the MD simulations. Residues ARG43, ILE45, and PHE57 were identified as crucial that were involved in interactions with the best hit. This is the first report of an allosteric binding site of Mtb-SK, which could largely address the selectivity issue associated with kinase inhibitors. PMID:27149193

  6. Propan-2-yl 2-(1,1,3-trioxo-2,3-dihydro-1λ6,2-benzothiazol-2-ylacetate

    Directory of Open Access Journals (Sweden)

    Muhammad Zia-ur-Rehman

    2012-09-01

    Full Text Available In the title molecule, C12H13NO5S, the benzisothiazole ring system is essentially planar (r.m.s. deviation = 0.0169 Å as is the –C—C(=O—O—C– sequence of atoms in the vicinity of the acetate group (r.m.s. deviation = 0.0044 Å. The mean plane of these atoms forms a dihedral angle of 88.41 (7° with the benzisothiazole ring system. In the crystal, weak C—H...O hydrogen bonds involving methylene and methyne H atoms form R43(20 graph-set motifs.

  7. Benzothiazole Derivatives. 48. Synthesis of 3-Alkoxycarbonylmethyl-6-bromo-2-benzothiazolones and 3-Alkoxycarbonylmethyl-6-nitro-2-benzothiazolones as Potential Plant Growth Regulators

    Directory of Open Access Journals (Sweden)

    Viktor Sutoris

    1999-03-01

    Full Text Available 3-Alkoxycarbonylmethyl-6-bromo- and 3-alkoxycarbonylmethyl-6-nitro-2-benzothiazolones were synthesized by reaction of alkylesters of halogenoacetic acids with 6-bromo-2-benzothiazolones and 6-nitro-2-benzothiazolones respectively. The compounds were tested for plant growth stimulating activity on wheat (Triticum aestivum. The bromo derivatives manifested 25.4 % average stimulating activity in comparison with the control. The stimulation activity of the nitro derivatives was not significant. Optimal structures of the compounds were obtained by a MMPI method, atomic charges and dipole moments were calculated by a semiempirical AM1 method. On the basis of molecular electrostatic potential it has been found that the biological activity of synthesized compounds depends on charge distribution in the molecules.

  8. Cation-Selective and Anion-Controlled Fluorogenic Behaviors of a Benzothiazole-Attached Macrocycle That Correlate with Structural Coordination Modes.

    Science.gov (United States)

    Ju, Huiyeong; Chang, Duk Jin; Kim, Seulgi; Ryu, Hyunsoo; Lee, Eunji; Park, In-Hyeok; Jung, Jong Hwa; Ikeda, Mari; Habata, Yoichi; Lee, Shim Sung

    2016-08-01

    We report how the metal cation and its counteranions cooperate in the complexation-based macrocyclic chemosensor to monitor the target metal ion via the specific coordination modes. The benzothiazolyl group bearing NO2S2-macrocycle L was synthesized, and its mercury(II) selectivity (for perchlorate salt) as a dual-probe channel (UV-vis and fluorescence) chemosensor exhibiting the largest blue shift and the fluorescence turn-off was observed. In the mercury(II) sensing with different anions, except ClO4(-) and NO3(-), no responses for mercury(II) were observed with other anions such as Cl(-), Br(-), I(-), SCN(-), OAc(-), and SO4(2-). A crystallographic approach for the mononuclear mercury(II) perchlorate complex [Hg(L)(ClO4)2]·0.67CH2Cl2 (1) and polymeric mercury(II) iodide complex [Hg(L)I2]n (2) revealed that the observed anion-controlled mercury(II) sensing in the fluorescence mainly stems from the endo- and exocoordination modes, depending on the anion coordinating ability, which induces either the Hg-Ntert bond formation or not. The detailed complexation process with mercury(II) perchlorate associated with the cation sensing was also monitored with the titration methods by UV-vis, fluorescence spectroscopy, and cold-spray ionization mass spectrometry. PMID:27391394

  9. The use of new modified poly(acrylamide chelating resin with pendent benzothiazole groups containing donor atoms in the removal of heavy metal ions from aqueous solutions

    Directory of Open Access Journals (Sweden)

    Semmedu Selvaraj Kalaivani

    2014-03-01

    Full Text Available The adsorption studies of poly(6-(ethoxybenzothiazole acrylamide (PEBTA, for Cu(II and Zn(II metal ions removal from an aqueous solution have been investigated, as a function of solution pH, adsorbent dose, contact time, initial metal ion concentration and temperature. The chemical and structural characteristics of the adsorbent were determined by the FT-IR, 1H-NMR, TGA, SEM, and EDAX analysis. The maximum adsorption capacities of the adsorbent for Cu(II and Zn(II ions, as calculated from the Langmuir isotherm model, were 273.5 and 216.4 mg/g, respectively. The adsorption kinetic studies show that the adsorption of Cu(II and Zn(II ions onto PEBTA follows the pseudo second order kinetic model. Thermodynamic parameters such as ΔG°, ΔH° and ΔS° were also evaluated, and it has been found that the adsorption process is feasible, spontaneous and exothermic in nature. Desorption studies were carried out using 0.3 N HCl, and it revealed that the adsorbed Cu(II and Zn(II ions can be easily removed. The adsorption–desorption process is reversible, and this indicates that PEBTA is an effective adsorbent for the removal of heavy metal ions from an aqueous medium.

  10. Biosynthesis of firefly luciferin in adult lantern: decarboxylation of L-cysteine is a key step for benzothiazole ring formation in firefly luciferin synthesis.

    Directory of Open Access Journals (Sweden)

    Yuichi Oba

    Full Text Available BACKGROUND: Bioluminescence in fireflies and click beetles is produced by a luciferase-luciferin reaction. The luminescence property and protein structure of firefly luciferase have been investigated, and its cDNA has been used for various assay systems. The chemical structure of firefly luciferin was identified as the D-form in 1963 and studies on the biosynthesis of firefly luciferin began early in the 1970's. Incorporation experiments using (14C-labeled compounds were performed, and cysteine and benzoquinone/hydroquinone were proposed to be biosynthetic component for firefly luciferin. However, there have been no clear conclusions regarding the biosynthetic components of firefly luciferin over 30 years. METHODOLOGY/PRINCIPAL FINDINGS: Incorporation studies were performed by injecting stable isotope-labeled compounds, including L-[U-(13C3]-cysteine, L-[1-(13C]-cysteine, L-[3-(13C]-cysteine, 1,4-[D6]-hydroquinone, and p-[2,3,5,6-D]-benzoquinone, into the adult lantern of the living Japanese firefly Luciola lateralis. After extracting firefly luciferin from the lantern, the incorporation of stable isotope-labeled compounds into firefly luciferin was identified by LC/ESI-TOF-MS. The positions of the stable isotope atoms in firefly luciferin were determined by the mass fragmentation of firefly luciferin. CONCLUSIONS: We demonstrated for the first time that D- and L-firefly luciferins are biosynthesized in the lantern of the adult firefly from two L-cysteine molecules with p-benzoquinone/1,4-hydroquinone, accompanied by the decarboxylation of L-cysteine.

  11. Solid phase extraction-preconcentration and high performance liquid chromatographic determination of 2-mercapto-(benzothiazole, benzoxazole and benzimidazole) using copper oxide nanoparticles.

    Science.gov (United States)

    Parham, Hooshang; Khoshnam, Farzaneh

    2013-09-30

    This study introduces a novel method of solid phase extraction (SPE), preconcentration and HPLC determination of 2-mercaptobenzimidazole (2MBI), 2-mercaptobenzoxazole (2MBO) and 2-mercaptobenzothiazole (2MBT) from an aqueous solution by a SPE cartridge loaded with copper oxide nanoparticles. Results demonstrated that copper oxide nanoparticles are quite efficient for extraction and preconcentration of trace amounts of these mercaptans at room temperature. The study also investigated the effects of parameters such as pH, buffer and its volume, electrolyte concentration, flow rate of the test solution, composition and volume of the desorbing solvent, accepted tolerable volume, amount of adsorbent, reusability of cartridges and evidence of some co-existing species on extraction and determination of the above mentioned mercaptans. The method showed good linearity for determination of these mercaptans in the range of 0.01-10 μg mL(-1) with regression coefficients better than 0.9969. The limits of detection (LODs) evaluations were 0.0021, 0.0027 and 0.0019 μg mL(-1) for 2MBT, 2MBO and 2MBI, respectively. The relative standard deviations (RSDs) for 0.2 μg mL(-1) and 5 μg mL(-1) of the measured mercaptans were below 3.04% and 4.23%, respectively. Ramin Power Plant (3000 MW, Ahvaz, Iran) cooling water containing some 2MBT (as corrosion inhibitor) was used as the real sample. Recovery tests with spiked levels of 2MBT, 2MBI and 2MBO were carried out and satisfied results were obtained.

  12. Synthesis of Novel Benzoxazole and Benzothiazole Derivatives%新型苯并噁唑(噻唑)衍生物的合成与表征

    Institute of Scientific and Technical Information of China (English)

    张英俊; 谭小华; 邵光; 彭志鸿; 安德烈

    2005-01-01

    通过N-氯乙酰或N,N′-二氯乙酰取代的含氮杂环中间体, 4,5-二氯-2-苯基-3-哒嗪酮分别与2-巯基苯并噁唑和2-巯基苯并噻唑反应,合成了8个未见文献报道的苯并噁唑和苯并噻唑衍生物,其结构经1H NMR, IR, MS及元素分析确认.

  13. {μ-2-[4-(1,3-Benzothiazol-2-ylphenyl]-2-azapropane-1,3-dithiolato-κ4S,S′:S,S′}bis[tricarbonyliron(I

    Directory of Open Access Journals (Sweden)

    Da-yong Jiang

    2012-03-01

    Full Text Available The title compound, [Fe2(C15H12N2S3(CO6], was prepared as an azadithiolatodiiron model for the active site of [FeFe]-hydrogenase. The Fe2S2 core adopts a butterfly shape, with each metal having a pseudo square-pyramidal geometry. The N-substituted azadithiolate is μ2-κ4S,S′:S,S′-coordinated to the Fe(CO3 moieties to form two fused six-membered rings with different conformations. The sum of the C—N—C angles around the N atom [356.85 (15°] indicates a flattening of the trigonal–pyramidal geometry about the N atom and an increase in the degree of sp2-hybridization.

  14. Nature of the lowest electron transitions in styryl bases benzothiazole derivatives and analogues bearing para-methoxy and -trifluoromethyl substituents in phenylyne moiety

    Science.gov (United States)

    Navozenko, O. M.; Naumenko, A. P.; Yashchuk, V. M.; Bricks, J. L.; Slominskii, Yu. L.; Ryabitskii, A. B.; Kachkovsky, O. D.

    2016-06-01

    Combined quantum-chemical and spectral investigation of cyanine bases derivatives of thiastyryls as well as their analogues with dimethylamino, metoxy and trifluorine-methyl substituents has been fulfilled. The calculations have shown that going from cationic styryl/metoxystyryl to the corresponding neutral bases is accompanied by substantial change of the equilibrium molecular geometry and charge distribution at atoms, while the experimental absorption band undergoes the essential hypsochromic shift. It is established that introducing on the donor groups in the bases causes negligible change of the carbon-carbon bond and atomic charges in the main chromophore, in contrast to the substantial changes of the magnitude and direction state dipole moments in both ground and excited states. It is found that the bases with the donor groups in benzthiazole moiety and with acceptor CF3 substituent demonstrate the inversion of the direction of the dipole moment. Based on the spectral and quantum-chemical study, one has proposed that some widening of the spectral bands is connected with the vibronic interaction, not with the second electron transition.

  15. Synthesis of some new 4-oxo-thiazolidines, tetrazole and triazole derived from 2-SH-benzothiazole and antimicrobial screening of some synthesized

    Directory of Open Access Journals (Sweden)

    Suaad M.H. Al-Majidi

    2014-12-01

    Triazole moieties reported condensation (MBT with ethylbromo acetate and potassium hydroxide by the fusion method and resulted in ester-2-mercaptobenzothiazole (7, which was treated with hydrazine hydrate to give a hydrazine derivative (8, then converting these compounds (8 to phenyl semicarbazide (9 and phenyl thiosemicarbazide (10 derivatives. Cyclization compounds (9,10 in alkaline media (4 N·NaOH gave triazoles compounds (11,12. Furthermore the compound (8 was converted to the dithiocarbazate salt (13 which was then cyclized with hydrazine hydrate to give substituted triazole (14. The prepared compounds were identified by spectral methods (FTIR, 1H NMR, 13C NMR and some of its physical properties were measured and furthermore the effects of the preparing compounds on some strains of bacteria were studied.

  16. A one-pot reaction to synthesize two types of fluorescent materials containing benzothiazolyl moiety.

    Science.gov (United States)

    Yu, Tianzhi; Zhang, Chengcheng; Zhao, Yuling; Chai, Haifang; Fan, Duowang; Ma, Ying; Yao, Shanglei; Li, Wentao

    2013-05-01

    Two different types of fluorescent materials containing benzothiazolyl moiety, 2-(benzothiazol-2-yl)phenol derivatives and 3-(benzothiazol-2-yl)coumarin derivatives, were synthesized synchronously using ethyl cyanoacetate, appropriate aromatic aldehyde and 2-aminothiophenol as the starting materials under the catalysis of benzoic acid by one-pot reaction. This method has the advantages of mild reaction conditions, easy processing and low waste. All synthesized compounds were characterized by elemental analysis, IR, (1)H NMR spectra. The structures of 2-(benzothiazol-2-yl)phenol derivatives, 2-(benzothiazol-2-yl)phenol (BTP) and 2-(benzothiazol-2-yl)naphthol (BTN), were determined by X-ray single crystal analysis. The UV-vis absorption and photoluminescence spectra of all synthesized compounds were investigated. The 2-(benzothiazol-2-yl)phenol derivatives exhibit bright green emissions and 3-(benzothiazol-2-yl)coumarin derivatives emit bright blue light in solutions.

  17. 1-(2-苯并噻唑)-3-(3,5-二溴吡啶)-三氮烯与铜的荧光反应及应用%Fluorescence reaction of 1-(2-benzothiazole)-3-(3, 5-dibromopyridyl)-triazene with copper ions and its application

    Institute of Scientific and Technical Information of China (English)

    章汝平; 张夏红; 何立芳

    2013-01-01

    A new triazene reagent 1-(2-benzothiazo le)-3-(3,5-dibromopyridyl)-triazene (BTPyBT) was synthesized and identified.The effect of conditions such as acidity,buffer solution dosage,copper ion concentration,reagent dosage,reaction temperature and reaction time on the fluorescence reaction of BTPyBT with copper was investigated.Based on this,a determination method of copper by fluorometry was established.The results showed that,BTPyBT reacted with copper at room temperature for 20 min to form a stable complex with composition ratio of 3 ∶ 1 in sodium borate-sodium hydroxide buffer solution at pH 9.16.The linear range of copper for the fluorometry was 0.5-80.0 μg/L.The determination limit was 0.2 μg/L.The proposed method has been applied to the determination of trace copper(Ⅱ) in mineral water,purified water and river water.The results were consist those obtained by atom absorption spectrometry,and the relative standard deviations (n =6) were 1.2%-4.7%.%合成并鉴定了一种新的三氮烯试剂1-(2-苯并噻唑)-3-(3,5-二溴吡啶)-三氮烯(BT-PyBT),考察了酸度、缓冲溶液用量、铜离子浓度、试剂用量、反应温度及反应时间等影响该试剂与铜发生荧光反应的条件,建立了一个测定铜的荧光分析方法.实验表明,在pH 9.16的硼砂-氢氧化钠缓冲液中,BTPyBT与铜离子在室温下反应20 min后可形成组成比为3∶1的稳定络合物.所建立铜的荧光分析方法的线性范围为0.5~80.0 μg/L,检出限为0.2μg/L.方法应用于矿泉水、纯净水及河水等水样品中痕量铜的测定,测定结果与原子吸收光谱法一致,相对标准偏差(n=6)为1.2%~4.7%.

  18. Discovery and Pharmacokinetic and Pharmacological Properties of the Potent and Selective MET Kinase Inhibitor 1-{6-[6-(4-Fluorophenyl)-[1,2,4]triazolo[4,3-b]pyridazin-3-ylsulfanyl]benzothiazol-2-yl}-3-(2-morpholin-4-ylethyl)urea (SAR125844).

    Science.gov (United States)

    Ugolini, Antonio; Kenigsberg, Mireille; Rak, Alexey; Vallée, Francois; Houtmann, Jacques; Lowinski, Maryse; Capdevila, Cécile; Khider, Jean; Albert, Eva; Martinet, Nathalie; Nemecek, Conception; Grapinet, Sandrine; Bacqué, Eric; Roesner, Manfred; Delaisi, Christine; Calvet, Loreley; Bonche, Fabrice; Semiond, Dorothée; Egile, Coumaran; Goulaouic, Hélène; Schio, Laurent

    2016-08-11

    The HGF/MET pathway is frequently activated in a variety of cancer types. Several selective small molecule inhibitors of the MET kinase are currently in clinical evaluation, in particular for NSCLC, liver, and gastric cancer patients. We report herein the discovery of a series of triazolopyridazines that are selective inhibitors of wild-type (WT) MET kinase and several clinically relevant mutants. We provide insight into their mode of binding and report unprecedented crystal structures of the Y1230H variant. A multiparametric chemical optimization approach allowed the identification of compound 12 (SAR125844) as a development candidate. In this chemical series, absence of CYP3A4 inhibition was obtained at the expense of satisfactory oral absorption. Compound 12, a promising parenteral agent for the treatment of MET-dependent cancers, promoted sustained target engagement at tolerated doses in a human xenograft tumor model. Preclinical pharmacokinetics conducted in several species were predictive for the observed pharmacokinetic behavior of 12 in cancer patients.

  19. Synthesis and Microbial Studies of New Pyridine Derivatives-Ⅲ

    Institute of Scientific and Technical Information of China (English)

    PATEL,N.B.; AGRAVAT,S. N.

    2007-01-01

    2-Amino substituted benzothiazole 4a-41 and p-acetamidobenzenesulfonyl chloride 2 were used to prepare 2-(p-aminophenylsulfonamido) substituted benzothiazole 6a-61 using mixture of pyridine and acetic anhydride which formed an electrophilic complex (N-acetyl pyridinium) to facilitate condensation to give desired product by removal of HCl. 2-{p-[(3-Carboxypyrid-2-yl)amino]phenylsulfonamido}benzothiazoles 8a-81 were synthesized from 2-chloropyridine-3-carboxylic acid 7 and 6a-61 in 2-ethoxy ethanol using Cu-powder and K2CO3. Acid chlorides 9a-91 were condensed with 2-hydroxyethyl piperazine 10 and 2,3-dichloropiperazine 11 for amide derivatives 2-(p-((3-(4-(2-hydroxyethyl)piperazin-1-ylcarbonyl)pyrid-2-yl)amino)phenylsulfonamido)benzothiazoles 12a -121 and 2-{p-[3-(2,3-dichloropiperazin-1-ylcarbonyl)pyrid-2-ylamino]phenylsulfonamido}benzothiazoles 13a-131 respectively. The structures of the new compounds have been established on the basis of their chemical analysis and spectral data (IR, 1H NMR and mass). All the compounds have been screened for their antibacterial and antifungal activities.

  20. Utility of 4-formylantipyrine in heterocyclic synthesis

    Directory of Open Access Journals (Sweden)

    Abdou O. Abdelhamid

    2010-04-01

    Full Text Available Pyrrolo[3,4-c]pyrazole-4,6(1H,5H-dione, pyrano[2,3-c]pyrazole-5-carbonitrile, pyrano[2,3-d]4-imidazolines, pyrido[2,1-b]benzimidazole, pyrido[2,1-b][1,3]benzoxazole, pyrido[2,1-b][1,3]benzothiazole and pyrido[2,1-b]quinazoline were synthesised from antipyrine derivatives with appropriate reagents such as maleimides, malononitrile, ethyl cyanoacetate, benzimidazole-2-acetonitrile, benzothiazole-2-acetonitrile, benzoxazol-2-acetonitrile, benzoylacetonitrile and other reagents. The newly synthesised compounds were established by elemental analysis, spectral data, and alternative synthetic routes whenever possible.

  1. 76 FR 72405 - Notice of Receipt of Requests to Voluntarily Cancel Certain Pesticide Registrations

    Science.gov (United States)

    2011-11-23

    ... (South Bldg.), 2777 S. Crystal Dr., Arlington, VA. Deliveries are only accepted during the Docket....), 2777 S. Crystal Dr., Arlington, VA. The hours of operation of this Docket Facility are from 8:30 a.m...-(Thiocyanomethylthio) benzothiazole Methylene bis (thiocyanate). 065092-00001 ZE LIN Chen Chalk Tralomethrin....

  2. 77 FR 8863 - Product Cancellation Order for Certain Pesticide Registrations

    Science.gov (United States)

    2012-02-15

    ... published for comment in the Federal Register issue of November 23, 2011 (76 FR 72405) (FRL-9327-2). The... Potomac Yard (South Bldg.), 2777 S. Crystal Dr., Arlington, VA. The hours of operation of this Docket...) benzothiazole, Preservative. Methylene bis (thiocyanate). 065092-00001 ZE LIN Chen Chalk Tralomethrin....

  3. Design, Synthesis and Anti-HIV Integrase Evaluation of 4-Oxo-4H-quinolizine-3-carboxylic Acid Derivatives

    Directory of Open Access Journals (Sweden)

    Li-Ming Hu

    2009-02-01

    Full Text Available 4-Oxo-4H-quinolizine-3-carboxylic acid derivatives bearing sulfamido, carboxylamido, benzimidazole and benzothiazole substituents have been designed and synthesized. The structures of these new compounds were confirmed by 1H-NMR, 13C- NMR, IR and ESI (or HRMS spectra. Compounds were screened for possible HIV integrase inhibitory activity.

  4. Fluorescent compounds for plastic scintillation applications

    International Nuclear Information System (INIS)

    Several 2-(2'-hydroxyphenyl)benzothiazole, -benzoxazole, and -benzimidazole derivatives have been prepared. Transmittance, fluorescence, light yield, and decay time characteristics of these compounds have been studied in a polystyrene matrix and evaluated for use in plastic scintillation detectors. Radiation damage studies utilizing a 60C source have also been performed

  5. Synthesis and Spectroscopic Characterisation of N-Alkyl Quaternary Ammonium Salts Typical Precursors of Cyanines

    Directory of Open Access Journals (Sweden)

    P. Almeida

    2002-03-01

    Full Text Available The synthesis and spectroscopic characterisation of some representative N-alkylsubstituted quaternary ammonium salts derived from benzothiazole, benzoxazole, benzoselenazole, indole and quinoline are described. These heterocyclic salts, bearing an activated methyl group in the 2-position in relation to the nitrogen atom and N-methyl, -pentyl, -hexyl and -decyl chains, are typical precursors of cyanine dyes.

  6. Fluorescent compounds for plastic scintillation applications

    Energy Technology Data Exchange (ETDEWEB)

    Pla-Dalmau, A.; Bross, A.D.

    1994-04-01

    Several 2-(2{prime}-hydroxyphenyl)benzothiazole, -benzoxazole, and -benzimidazole derivatives have been prepared. Transmittance, fluorescence, light yield, and decay time characteristics of these compounds have been studied in a polystyrene matrix and evaluated for use in plastic scintillation detectors. Radiation damage studies utilizing a {sup 60}C source have also been performed.

  7. Synthesis of substituted benzoxazoles by the iron(Ⅲ)-catalyzed aerobic oxidation process

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The FeCl3-catalyzed aerobic oxidation process for the synthesis of benzoxazoles,benzothiazole and benzimidazole has been discovered.This method has proved to be effective to a wide range of substrates,and it has been applied for the synthesis of JTP-426467.

  8. Novel Piperine Derivatives with Antidiabetic Effect as PPAR-γ Agonists.

    Science.gov (United States)

    Kharbanda, Chetna; Alam, Mohammad Sarwar; Hamid, Hinna; Javed, Kalim; Bano, Sameena; Ali, Yakub; Dhulap, Abhijeet; Alam, Perwez; Pasha, M A Qadar

    2016-09-01

    Piperine is an alkaloid responsible for the pungency of black pepper. In this study, piperine isolated from Piper nigrum L. was hydrolyzed under basic condition to obtain piperic acid and was used as precursor to carry out the synthesis of twenty piperine derivatives containing benzothiazole moiety. All the benzothiazole derivatives were evaluated for their antidiabetic potential by OGT test followed by assessment of active derivatives on STZ-induced diabetic model. It was observed that nine of twenty novel piperine analogues (5b, 6a-h), showed significantly higher antidiabetic activity in comparison with rosiglitazone (standard). Furthermore, these active derivatives were evaluated for their action as PPAR-γ agonists demonstrating their mechanism of action. The effects on body weight, lipid peroxidation, and hepatotoxicity after administration with active derivatives were also studied to further establish these derivatives as lead molecules for treatment of diabetes with lesser side-effects. PMID:27037532

  9. Synthesis of Firefly Luciferin Analogues and Evaluation of the Luminescent Properties.

    Science.gov (United States)

    Ioka, Shuji; Saitoh, Tsuyoshi; Iwano, Satoshi; Suzuki, Koji; Maki, Shojiro A; Miyawaki, Atsushi; Imoto, Masaya; Nishiyama, Shigeru

    2016-06-27

    Five new firefly luciferin (1) analogues were synthesized and their light emission properties were examined. Modifications of the thiazoline moiety in 1 were employed to produce analogues containing acyclic amino acid side chains (2-4) and heterocyclic rings derived from amino acids (5 and 6) linked to the benzothiazole moiety. Although methyl esters of all of the synthetic derivatives exhibited chemiluminescence activity, only carboluciferin (6), possessing a pyrroline-substituted benzothiazole structure, had bioluminescence (BL) activity (λmax =547 nm). Results of bioluminescence studies with AMP-carboluciferin (AMP=adenosine monophosphate) and AMP-firefly luciferin showed that the nature of the thiazoline mimicking moiety affected the adenylation step of the luciferin-luciferase reaction required for production of potent BL. In addition, BL of 6 in living mice differed from that of 1 in that its luminescence decay rate was slower. PMID:27220106

  10. Preparation and fluorescent properties of a complex probe based on inorganic QDs and organic dye

    International Nuclear Information System (INIS)

    A novel complex fluorescent probe based on quantum dots and organic dye (QDs-TO) was designed and prepared by incorporating a benzothiazole derivative into QDs-1-(3-amidepropyl)-4-methylquinoline. The complex probe was characterized by FT-IR and TG/DTA. The emission wavelength of QDs-1-(3-amidepropyl)-4-methylquinoline was found at 475 nm and a new peak corresponding to QDs-TO appeared at 550 nm, indicating that benzothiazole derivative can react with QDs-1-(3-amidepropyl)-4-methylquinoline to afford QDs-TO. Furthermore, the emission wavelength of QDs shifted blue while the characteristic peak of TO shifted red during the reaction. This suggests that the probe may be useful for biological labeling in offering an efficient method to study the interrelation between quantum dots and organic dyes.

  11. 2-Arylbenzothiazole, benzoxazole and benzimidazole derivatives as fluorogenic substrates for the detection of nitroreductase and aminopeptidase activity in clinically important bacteria.

    Science.gov (United States)

    Cellier, Marie; Fabrega, Olivier J; Fazackerley, Elizabeth; James, Arthur L; Orenga, Sylvain; Perry, John D; Salwatura, Vindhya L; Stanforth, Stephen P

    2011-05-01

    A series of 2-(2-nitrophenyl)benzothiazole 7, 2-(2-nitrophenyl)benzoxazole 10 and 2-(2-nitrophenyl)benzimidazole 13 derivatives have been synthesised and assessed as indicators of nitroreductase activity across a range of clinically important Gram negative and Gram positive bacteria. The majority of Gram negative bacteria produced strongly fluorescent colonies with substrates 7 and 10 whereas fluorescence production in Gram positive bacteria was less widespread. The l-alanine 16 and 19 and β-alanine 21 and 23 derivatives have been prepared from 2-(2-aminophenyl)benzothiazole 14 and 2-(2-aminophenyl)benzoxazole 17. These four compounds have been evaluated as indicators of aminopeptidase activity. The growth of Gram positive bacteria was generally inhibited by these substrates but fluorescent colonies were produced with the majority of Gram negative bacteria tested.

  12. One-pot non-enzymatic formation of firefly luciferin in a neutral buffer from p-benzoquinone and cysteine.

    Science.gov (United States)

    Kanie, Shusei; Nishikawa, Toshio; Ojika, Makoto; Oba, Yuichi

    2016-01-01

    Firefly luciferin, the substrate for the bioluminescence reaction of luminous beetles, possesses a benzothiazole ring, which is rare in nature. Here, we demonstrate a novel one-pot reaction to give firefly luciferin in a neutral buffer from p-benzoquinone and cysteine without any synthetic reagents or enzymes. The formation of firefly luciferin was low in yield in various neutral buffers, whereas it was inhibited or completely prevented in acidic or basic buffers, in organic solvents, or under a nitrogen atmosphere. Labelling analysis of the firefly luciferin using stable isotopic cysteines showed that the benzothiazole ring was formed via the decarboxylation and carbon-sulfur bond rearrangement of cysteine. These findings imply that the biosynthesis of firefly luciferin can be developed/evolved from the non-enzymatic production of firefly luciferin using common primary biosynthetic units, p-benzoquinone and cysteine. PMID:27098929

  13. Antimicrobial evaluation of diaminothiazoloylbenzothiazoles

    Directory of Open Access Journals (Sweden)

    A. Yardily

    2016-05-01

    Full Text Available A series of 2-(4-amino-2-aryl/alkylaminothiazol-5-oyl benzothiazole derivatives were synthesized from amidinothioureas and 2-(2-bromoacetylbenzothiazole with triethylamine. Their structures were established on the basis of IR, 1H NMR, 13C NMR and mass spectral analyses. All the synthesized compounds were screened for their antibacterial, antifungal and antimycobacterial potential. All the compounds showed significant activity against the microorganisms tested.

  14. Determination of fungicides in residual tanning floats using solid phase micro extraction

    OpenAIRE

    Font Vallès, Joaquim; Reyes Reyes, Maria; Cuadros, Sara; Bacardit Dalmases, Anna; Ollé Otero, Lluís; Marsal Monge, Agustín

    2013-01-01

    Solid-phase microextraction (SPME) was optimized for extraction of the leather preservative agents 2-(thiocyanomethylthio)-benzothiazole (TCMTB), 4-chloro-3-methylphenol (PCMC), 2-phenylphenol (OPP), 2-Octyl-3(2H)-isothiazolone (OIT), 2-mercaptobenzothiazol (MBT) and 3-iodo-2-propynyl-butylcarbamate (IPBC) in spent tanning floats. Determination was carried out by high performance liquid chromatography (HPLC) with photo diode array detection (PDA). The following parameters were studied to ach...

  15. A convenient route for synthesis and antimicrobial evaluation of bis (diimino benzothiazolo pyrimido pyrimidines

    Directory of Open Access Journals (Sweden)

    Balasaheb D. Kalyankar

    2014-12-01

    Full Text Available Guanidine hydrochloride (1 on treatment with bis(methylthiomethylene malonitrile (2 in N,N-dimethyl formamide (DMF and catalytic amount of anhydrous potassium carbonate gives diimino pyrimido pyrimidine (3. The later were further reacted with various substituted 2-amino benzothiazoles (4 to gives bis (diimino benzothiazolo pyrimido pyrimidines (5a-g. All these synthesized compounds were screened for their antimicrobial activity.

  16. What Is Its Real Existing Form? ---Theoretical and Experimental Studies on 2-Mercaptobenzothiazole

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The geometry of 2-mercaptobenzothiazole (MBT) and its tautomeric form of benzo- thiazole-2-thione are optimized at B3LYP/6-311G** and HF/6-311G** levels, respectively. The crystal structure of benzothiazole-2-thione and its FTIR spectra are also obtained. From the calcu- lated and experimental data, it can be concluded that in gas-phase and solid-state, the real existing form of 2-mercaptobenzothiazole is the thione-form of MBT.

  17. Two novel fluorescent calix[4]arene derivatives with benzoazole units in 1,3-alternate conformation for selective recognition to Fe~(3+) and Cr~(3+)

    Institute of Scientific and Technical Information of China (English)

    He Wen Wang; Ya Qing Feng; Chen Chen; Jin Qiang Xue

    2009-01-01

    Two novel fluorescent calix[4]arene derivatives 1a and 1b with benzoxazole or benzothiazole units in 1,3-alternate conformation have been synthesized and characterized by IR, ~1H NMR, ~(13)C NMR and MS. Their complexation properties to different heavy and transition metal ions have been studied by UV-vis spectroscopy and fluorescence spectrometer. Compounds la and lb show selective recognition to Fe~(3+) and Cr~(3+).

  18. Syntheses and electroluminescent properties of two europium ternary complexes Eu(DBM){sub 3}(PBO) and Eu(DBM){sub 3}(PBT)

    Energy Technology Data Exchange (ETDEWEB)

    Guan Min [State Key Laboratory of Rare Earth Materials Chemistry and Applications, Peking University, Beijing 100871 (China); Gao Lihua [Department of Chemistry, Beijing Normal University, Beijing 100875 (China); Wang Shanshan [State Key Laboratory of Rare Earth Materials Chemistry and Applications, Peking University, Beijing 100871 (China); Huang Chunhui [State Key Laboratory of Rare Earth Materials Chemistry and Applications, Peking University, Beijing 100871 (China)], E-mail: chhuang@pku.edu.cn; Wang Kezhi [Department of Chemistry, Beijing Normal University, Beijing 100875 (China)

    2007-12-15

    Two europium complexes, Eu(DBM){sub 3}(PBO) and Eu(DBM){sub 3}(PBT) (DBM=dibenzoylmethanato, PBO=2-(2-pyridyl)benzoxazole, PBT=2-(2-pyridyl)benzothiazole), were prepared and used as emitting materials in organic electroluminescent (EL) devices. The devices with the structures ITO/TPD/Eu(DBM){sub 3}(PBO) (or Eu(DBM){sub 3}(PBT)/BCP/Alq{sub 3}/Mg:Ag/Ag emit red light originating from the europium complexes.

  19. Design, synthesis and antitumor activity of 3-substituted quinolone derivatives (Ⅰ)

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A series of quinolone derivatives containing benzimidazole, benzoxazole or benzothiazole ring were synthesized. The cytotoxicity of 12 new compounds was evaluated in KB, Be17402, A2780 and HT-29 cell lines. Most of synthesized compounds showed moderate inhibitory activity against cancer cells. The inhibitory activities of 6k, against KB and A2780 tumor cells are comparable to that of topotecan, one of topoisomerase I inhibitors.

  20. Synthèse et évalutaion de nouveaux composés organiques et phosphorés contre les effets des rayonnements ionisants. Etude de leur mécanisme d'action in vitro.

    OpenAIRE

    Prouillac, C.

    2006-01-01

    This work falls under a research program. The aim was to synthesize new organic phosphorylated compounds having an interesting radiopharmacological activity without toxicity. That's why, we carried out the synthesis of new benzothiazole and thiadiazole N-substituted derivatives as thiols, aminothiols, acids thiosulfonic and phosphorothioates. All these compounds were characterized by NMR (proton, carbon, phosphorus, 2D), by mass spectrometry, elementary analyzes and for some of them by diffra...

  1. A Multidisciplinary Investigation to Determine the Structure and Source of Dimeric Impurities in AMG 517 Drug Substance

    Directory of Open Access Journals (Sweden)

    Maria Victoria Silva Elipe

    2009-01-01

    Full Text Available In the initial scale-up batches of the experimental drug substance AMG 517, a pair of unexpected impurities was observed by HPLC. Analysis of data from initial LC-MS experiments indicated the presence of two dimer-like molecules. One impurity had an additional sulfur atom incorporated into its structure relative to the other impurity. Isolation of the impurities was performed, and further structural elucidation experiments were conducted with high-resolution LC-MS and 2D NMR. The dimeric structures were confirmed, with one of the impurities having an unexpected C-S-C linkage. Based on the synthetic route of AMG 517, it was unlikely that these impurities were generated during the last two steps of the process. Stress studies on the enriched impurities were carried out to further confirm the existence of the C-S-C linkage in the benzothiazole portion of AMG 517. Further investigation revealed that these two dimeric impurities originated from existing impurities in the AMG 517 starting material, N-acetyl benzothiazole. The characterization of these two dimeric impurities allowed for better quality control of new batches of the N-acetyl benzothiazole starting material. As a result, subsequent batches of AMG 517 contained no reportable levels of these two impurities

  2. Synthesis and Anti-TMV Activity of Dialkyl/dibenzyl 2-((6-Substituted-benzo[d]thiazol-2-ylamino(benzofuran-2-ylmethyl Malonates

    Directory of Open Access Journals (Sweden)

    Meichuan Li

    2013-11-01

    Full Text Available Starting from benzofuran-2-methanal, 6-substituted benzothiazole-2-amines and malonic esters, sixteen title compounds were designed and synthesized seeking to introduce anti-TMV activity. The structures of the newly synthesized compounds were confirmed by 1H-NMR, 13C-NMR, IR spectra, and MS (HREI analysis. The bioassays identified some of these new compounds as having moderate to good anti-TMV activity. The compounds 5i and 5m have good antiviral activity against TMV with a curative rate of 52.23% and 54.41%, respectively, at a concentration of 0.5 mg/mL.

  3. New sulfenamide accelerators derived from 'safe' amines for the rubber and tyre industry.

    Science.gov (United States)

    Wacker, C D; Spiegelhalder, B; Preussmann, R

    1991-01-01

    A reduction of the high exposures to N-nitrosamines in the rubber and tyre industry is possible using the concept of 'safe' amines, in which vulcanization accelerators contain amine moieties that are both difficult to nitrosate and, on nitrosation, yield noncarcinogenic N-nitroso compounds. The toxicological and technological properties of more than 50 benzothiazole sulfenamides derived from 'safe' amines have been evaluated. Some of the new compounds show excellent vulcanization properties and seem suitable as replacements for traditional accelerators in this class of compounds. PMID:1855923

  4. A wood preservative metabolite in river water.

    Science.gov (United States)

    Khoroshko, Larisa O; Petrova, Varvara N; Viktorovskii, Igor V; Lahtiperä, Mirja; Sinkkonen, Seija; Paasivirta, Jaakko

    2005-01-01

    A previously unknown pollutant in river water was identified to be 2-mercaptobenzothiazole (2-MBT) by interpretation and simulation of its GC/LRMS spectrum. Further GC/HRMS measurement of the isotope composition of the molecular ion verified this structure. 2-MBT is a well-known agent for corrosion inhibition and a stable metabolite of several other benzothiazoles. The present 2-MBT trace was most probably a metabolite of the wood preservative TCMTB which leaked from an upstream sawmill. The metabolite had been detected earlier in urine of the sawmill workers, but now was identified in the recipient water environment for the first time. PMID:15768735

  5. Bench-Scale Synthetic Optimization of 1,2-bis(2-aminophenylthio)ethane (APO-Link) Used in the Production of APO-BMI Resin

    Energy Technology Data Exchange (ETDEWEB)

    Hilary Wheeler; Crystal Densmore

    2007-07-31

    The diamine reagent 1,2-bis(2-aminophenylthio)ethane is no longer commercially available but still required for the synthesis of the bismaleimide resin, APO-BMI, used in syntactic foams. In this work, we examined the hydrolysis of benzothiazole followed the by reaction with dichloroethane or dibromoethane. We also studied the deprotonation of 2-aminothiophenol followed by the reaction with dibromoethane. We optimized the latter for scale-up by scrutinizing all aspects of the reaction conditions, work-up and recrystallization. On bench-scale, our optimized procedure consistently produced a 75-80% overall yield of finely divided, high purity product (>95%).

  6. Antimicrobial Evaluation and Synthesis of Some Phenylpyrazolo benzothiazolo quinoxaline Derivatives

    Directory of Open Access Journals (Sweden)

    CH. Sridevi

    2009-01-01

    Full Text Available 2,3-Diphenyl quinoxaline (SI was fused with 2-amino benzothiazoles (SII by a methylene bridge, which was then allowed for acetylation. The acetylated product (SIV was made to react with different aromatic aldehydes to give chalcones (SV1-SV5. Chalcones refluxed with substituted acid hydrazides to afford different phenyl pyrazolo benzothiazolo quinoxaline derivatives (SVI1-SVI15. The structure of chalcones and phenyl pyrazolo benzothiazolo quinoxaline derivatives were confirmed by M.P, TLC and spectral data. All the synthesized compounds were screened for their antimicrobial activities.

  7. 2-[2-(3-Methoxyphenyl-2-oxoethyl]-1,2-benzisothiazol-3(2H-one 1,1-dioxide

    Directory of Open Access Journals (Sweden)

    Masood Parvez

    2010-03-01

    Full Text Available In the title compound, C16H13NO5S, the benzothiazole unit is essentially planar [maximum deviation = 0.0501 (10 Å for the S atom] and is oriented at a dihedral angle of 67.85 (5° with respect to the methoxy-substituted benzene ring. The mean plane of the methoxy group is oriented at 14.3 (3° with respect to the benzene ring to which it is attached. In the crystal structure, weak C—H...O hydrogen bonds form macrocyclic rings with R22(10 and R22(12 motifs.

  8. Synthesis and Analytical Application of Bis(2-diazoaminobenzothiazoyl)-benzidine to Determination of Mercury Ion by Fluorimetry

    Institute of Scientific and Technical Information of China (English)

    JIANG Run-sheng; FENG Feng; CHEN Ze-zhong; BAI Yun-feng; LIN Sen; FU Guo-liang

    2009-01-01

    A new fluorescent reagent bis(2-diazoaminobenzothiazoyl)-benzidine(BDABTB) was synthesized by combining benzothiazole with benzidine and triazene reagent. The product was confirmed by elemental analysis, 1HNMR and FTIR. The excitation and emission wavelengths of BDABTB were 214 and 338 nm in a basic medium, respectively. The fluorescence was quenched by Hg~(2+) selectively and sensitively. The linear range of Hg~(2+) was 1.0×10~(-8)-1.0×10~(-5) mol/L with a detection limit of 5.0×10~(-10) mol/L. It has been used to determine trace Hg~(2+) in water sample with satisfactory results.

  9. Insights on the binding of thioflavin derivative markers to amyloid fibril models and Aβ{sub 1-40} fibrils from computational approaches

    Energy Technology Data Exchange (ETDEWEB)

    Alí-Torres, Jorge; Rimola, Albert; Sodupe, Mariona [Departament de Química, Universitat Autònoma de Barcelona, Bellaterra 08193 (Spain); Rodriguez-Rodríguez, Cristina [Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, V6T 1Z1 (Canada)

    2014-10-06

    The present contribution analyzes the binding of ThT and neutral ThT derivatives to a β-sheet model by means of quantum chemical calculations. In addition, we study the properties of four molecules: (2-(2-hydroxyphenyl)benzoxazole (HBX), 2-(2-hydroxyphenyl)benzothiazole (HBT) and their respective iodinated compounds, HBXI and HBTI, in binding to amyloid fibril models and Aβ{sub 1-40}fibrils by using a combination of docking, molecular dynamics and quantum mechanics calculations.

  10. Diacetoxyiodobenzene assisted C-O bond formation via sequential acylation and deacylation process: synthesis of benzoxazole amides and their mechanistic study by DFT.

    Science.gov (United States)

    Nahakpam, Lokendrajit; Chipem, Francis A S; Chingakham, Brajakishor S; Laitonjam, Warjeet S

    2016-08-10

    An efficient method for the transformation of N-substituted-N'-benzoylthioureas to substituted N-benzoxazol-2-yl-amides using diacetoxyiodobenzene (DIB) is described in this work. The transformation follows the C-O bond formation leading to the benzoxazole derivative, due to oxidative dehydrogenation by DIB, instead of the expected C-S bond formation of the benzothiazole moiety. The C-O bond formation leading to benzoxazole is due to consecutive acylation and deacylation in conjunction with the reduction of two moles of DIB. A plausible mechanism was proposed for the reaction and density functional calculations were also performed to study the reaction mechanism.

  11. Ti (IV complexes of some heterocyclic ligands. Synthesis, characterization and ethylene polymerization activity

    Directory of Open Access Journals (Sweden)

    Hamdi Ali Elagab

    2016-03-01

    Full Text Available 31 complexes of bis - (benzimidazole, benzothiazole and benzoxazole compounds with Ti (IV metal centers were synthesized, characterized, activated with methylalumoxane (MAO and then tested for catalytic ethylene polymerization. The activities of the various catalysts were found to be functions of the hetero atoms in the ligand frameworks. The highest activity was obtained with 39 / MAO (573 kg PE / mol cat. h. The produced polyethylenes showed high molecular weights (up to 1.5 ×106 g/mol and broad molecular weight distributions (PD = 65. This could result from different interactions of the MAO counterion with the heteroatoms of the catalyst ligand generating different active sites.

  12. Design and synthesis of benzoxazole containing indole analogs as peroxisome proliferator-activated receptor-γ/δ dual agonists.

    Science.gov (United States)

    Gim, Hyo Jin; Cheon, Ye-Jin; Ryu, Jae-Ha; Jeon, Raok

    2011-05-15

    A series of benzoxazole or benzothiazole containing indole analogs, 6-alkoxyindole-2-carboxylic acids and 5-alkoxy-3-indolylacetic acids, were synthesized as novel candidates of PPARγ/δ dual agonists and their ligand activities for PPAR subtypes (α, γ, and δ) were investigated. In transient transactivation assay, several compounds activated PPARγ and δ with little activity of PPARα. Putative binding mode of the compounds 1a and 2a in the active site of PPARγ was similar with that of rosiglitazone and the molecular modeling provides molecular insight to the observed activity.

  13. Synthesis and antiulcer activity studies of 2-(1′-iminothioimido substituted-1′-substituted phenylbenzoic acids

    Directory of Open Access Journals (Sweden)

    Subudhi B

    2008-01-01

    Full Text Available Certain 2-(1′-iminothioimido substituted-1′-substituted phenybenzoic acids (P 1-9 were synthesized by reaction of phthalic anhydride with benzotriazole, 2-mercapto benzothiazole and 2-p-amino phenyl benzimidazole, respectively (A 1-3 followed by imine formation with Schiff bases of thiourea with salicylaldehyde, furfuraldehyde and 1-phenyl-3-methyl-5-pyrazolone. Antiulcer activity was evaluated using reduction in total acidity, free acidity and ulcer index as parameters. Compounds P 3 , P 6 , P 7 and P 9 (100 mg/kg showed significant (P< 0.001 antiulcer action compared to control and omeprazole (40 mg/kg.

  14. Tribological study of a highly hydrolytically stable phenylboronic acid ester containing benzothiazolyl in mineral oil

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhipeng [School of Chemistry and Chemical Engineering, Key Laboratory for Thin Film and Microfabrication of the Ministry of Education, Shanghai Jiao Tong University, 200240 (China); Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Li, Xiufeng; Zhang, Yawen [School of Chemistry and Chemical Engineering, Key Laboratory for Thin Film and Microfabrication of the Ministry of Education, Shanghai Jiao Tong University, 200240 (China); Ren, Tianhui, E-mail: thren@sjtu.edu.cn [School of Chemistry and Chemical Engineering, Key Laboratory for Thin Film and Microfabrication of the Ministry of Education, Shanghai Jiao Tong University, 200240 (China); Zhao, Yidong [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100039 (China); Zeng, Xiangqiong; Heide, E. van der [Laboratory for Surface Technology and Tribology, University of Twente, Drienerlolaan 5, 7522 NB Enschede (Netherlands)

    2014-07-01

    A novel long chain alkyl phenylboronic acid ester containing heterocyclic compound, bis (1-(benzothiazol-2-ylthio) propan-2-yl)-4-dodecylphenylboronic acid ester (DBBMT), was synthesized and characterized. The hydrolytic stability of the DBBMT was evaluated and the results show that DBBMT is of outstanding hydrolytic stability compared with normal borate esters, which indicates that the designed molecular structure, by introducing benzene ring to conjugate with the electron-deficient boron and the benzothiazole as a hinder group, is effective on obtaining a hydrolytically stable long chain alkyl phenylboronic acid ester. The tribological properties of DBBMT and ZDDP in mineral base oil were evaluated using a four-ball tribometer, which suggests that the DBBMT possesses comprehensive tribological properties and could be a potential candidate for the replacement of ZDDP. Furthermore, in order to understand the tribological behaviors, the worn surface was analyzed by X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge structure (XANES) spectroscopy. The results indicate that the elements S, B, O and Fe perform complicated tribochemical reactions to form the compact tribological film composed of B{sub 2}O{sub 3}, FeS, Fe{sub 3}O{sub 4} and FeSO{sub 4}.

  15. Plant-plant-microbe mechanisms involved in soil-borne disease suppression on a maize and pepper intercropping system.

    Directory of Open Access Journals (Sweden)

    Min Yang

    Full Text Available BACKGROUND: Intercropping systems could increase crop diversity and avoid vulnerability to biotic stresses. Most studies have shown that intercropping can provide relief to crops against wind-dispersed pathogens. However, there was limited data on how the practice of intercropping help crops against soil-borne Phytophthora disease. PRINCIPAL FINDINGS: Compared to pepper monoculture, a large scale intercropping study of maize grown between pepper rows reduced disease levels of the soil-borne pepper Phytophthora blight. These reduced disease levels of Phytophthora in the intercropping system were correlated with the ability of maize plants to form a "root wall" that restricted the movement of Phytophthora capsici across rows. Experimentally, it was found that maize roots attracted the zoospores of P. capsici and then inhibited their growth. When maize plants were grown in close proximity to each other, the roots produced and secreted larger quantities of 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H-one (DIMBOA and 6-methoxy-2-benzoxazolinone (MBOA. Furthermore, MBOA, benzothiazole (BZO, and 2-(methylthio-benzothiazole (MBZO were identified in root exudates of maize and showed antimicrobial activity against P. capsici. CONCLUSIONS: Maize could form a "root wall" to restrict the spread of P. capsici across rows in maize and pepper intercropping systems. Antimicrobe compounds secreted by maize root were one of the factors that resulted in the inhibition of P. capsici. These results provide new insights into plant-plant-microbe mechanisms involved in intercropping systems.

  16. Environmental impact of highway construction and repair materials on surface and ground waters. Case study: crumb rubber asphalt concrete.

    Science.gov (United States)

    Azizian, Mohammad F; Nelson, Peter O; Thayumanavan, Pugazhendhi; Williamson, Kenneth J

    2003-01-01

    The practice of incorporating certain waste products into highway construction and repair materials (CRMs) has become more popular. These practices have prompted the National Academy of Science, National Cooperative Highway Research Program (NCHRP) to research the possible impacts of these CRMs on the quality of surface and ground waters. State department of transportations (DOTs) are currently experimenting with use of ground tire rubber ( crumb rubber) in bituminous construction and as a crack sealer. Crumb rubber asphalt concrete (CR-AC) leachates contain a mixture of organic and metallic contaminants. Benzothiazole and 2(3H)-benzothiazolone (organic compounds used in tire rubber manufacturing) and the metals mercury and aluminum were leached in potentially harmful concentrations (exceeding toxic concentrations for aquatic toxicity tests). CR-AC leachate exhibited moderate to high toxicity for algae ( Selenastrum capriconutum) and moderate toxicity for water fleas ( Daphnia magna). Benzothiazole was readily removed from CR-AC leachate by the environmental processes of soil sorption, volatilization, and biodegradation. Metals, which do not volatilize or photochemically or biologically degrade, were removed from the leachate by soil sorption. Contaminants from CR-AC leachates are thus degraded or retarded in their transport through nearby soils and ground waters. PMID:14522190

  17. {beta} - amyloid imaging probes

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Jae Min [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2007-04-15

    Imaging distribution of {beta} - amyloid plaques in Alzheimer's disease is very important for early and accurate diagnosis. Early trial of the {beta} -amyloid plaques includes using radiolabeled peptides which can be only applied for peripheral {beta} - amyloid plaques due to limited penetration through the blood brain barrier (BBB). Congo red or Chrysamine G derivatives were labeled with Tc-99m for imaging {beta} - amyloid plaques of Alzheimer patient's brain without success due to problem with BBB penetration. Thioflavin T derivatives gave breakthrough for {beta} - amyloid imaging in vivo, and a benzothiazole derivative [C-11]6-OH-BTA-1 brought a great success. Many other benzothiazole, benzoxazole, benzofuran, imidazopyridine, and styrylbenzene derivatives have been labeled with F-18 and I-123 to improve the imaging quality. However, [C-11]6-OH-BTA-1 still remains as the best. However, short half-life of C-11 is a limitation of wide distribution of this agent. So, it is still required to develop an Tc-99m, F-18 or I-123 labeled agent for {beta} - amyloid imaging agent.

  18. Ground- and excited-state structural orientation of 2-(2`-hydroxyphenyl)benzazoles in cyclodextrins

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, E.L.; Dey, J.; Warner, I.M. [Louisiana State Univ., Baton Rouge, LA (United States)

    1996-12-12

    The effects of {alpha}-, {beta}-, {gamma}-, and 2,6-di-O-methyl-{beta}-cyclodextrins (CDs) on the ground- and excited-state properties of 2-(2`-hydroxyphenyl)benzoxazole, 2-(2`-hydroxyphenyl)benzothiazole, and 2-(2`-hydroxyphenyl)benzimidazole in aqueous media are investigated. Steady-state fluorescence measurements are used to characterize the interaction of CDs with these azoles. Absorbance measurements indicate increased solubility of the azoles in aqueous solutions of CDs. Measurements of acidity constants (pK{sub a}) and data from induced circular dichroism indicate increased ground- and excited-state acidities of the phenolic protons of the molecules in the presence of CDs and axial orientation of the molecules within the CD cavity, respectively. The data further suggest a planar structure for HBO and a twisted confirmation for both HBT and HBI. The association constants of the inclusion complexes have also been estimated. These studies are further supplemented by comparative spectroscopic studies of 2-(2`-methoxyphenyl)benzothiazole in aqueous solutions of CDs. On the basis of the spectral data acquired, it is believed that the HBA molecules exist as zwitterionic tautomers in the presence of CDs. 35 refs., 6 figs., 2 tabs.

  19. Removal of the 2-Mercaptobenotiazole from Model Wastewater by Ozonation

    Directory of Open Access Journals (Sweden)

    Jan Derco

    2014-01-01

    Full Text Available The feasibility of ozonation process for 2-mercaptobenzothiazole (2-MBT removal follows from results of ozonation of the model wastewater. Total removal of 2-MBT was observed after 20 minutes of ozonation. Very good reproducibility of repeated ozonation trials including sampling and analysis was observed. However, the majority of dissolved organic carbon (DOC and chemical oxygen demand (COD remained in the reaction mixture. Benzothiazole (BT and 2-hydroxybenzothiazole (OBT intermediates were identified during degradation of 2-MBT with ozone. In addition to the above benzothiazole derivatives, the creation of some other organic compounds follows from results of mass balance. The best fits of experimental data were obtained using the first kinetic model for 2-MBT and zero-order kinetic model for COD and DOC. The reaction time of 60 minutes can be considered as effective with regard to controlled oxidation in order to increase a portion of partially oxidized substances. Higher biodegradability and lower toxicity of ozonation products on respiration activity of activated sludge microorganisms was observed at higher ozonation time.

  20. 1,3-Substituted Imidazolidine-2,4,5-triones: Synthesis and Inhibition of Cholinergic Enzymes

    Directory of Open Access Journals (Sweden)

    Josef Jampilek

    2011-09-01

    Full Text Available A series of novel and highly active acetylcholinesterase and butyrylcholinesterase inhibitors derived from substituted benzothiazoles containing an imidazolidine-2,4,5-trione moiety were synthesized and characterized. The molecular structure of 1-(2,6-diisopropyl-phenyl-3-[(1R-1-(6-fluoro-1,3-benzothiazol-2-ylethyl]-imidazolidine-2,4,5-trione (3g was determined by single-crystal X-ray diffraction. Both optical isomers are present as two independent molecules in the triclinic crystal system. The lipophilicity of the compounds was determined as the partition coefficient log Kow using the traditional shake-flask method. The in vitro inhibitory activity on acetylcholinesterase from electric eel and butyrylcholinesterase isolated from equine serum was determined. The inhibitory activity on acetylcholinesterase was significantly higher than that of the standard drug rivastigmine. The discussed compounds are also promising inhibitors of butyrylcholinesterase, as some of the prepared compounds inhibit butyrylcholinesterase better than the internal standards rivastigmine and galanthamine. The highest inhibitory activity (IC50 = 1.66 μmol/L corresponds to the compound 1-(4-isopropylphenyl-3-[(R-1-(6-fluorobenzo[d]thiazol-2-ylethyl]imidazolidine-2,4,5-trione (3d. For all the studied compounds, the relationships between the lipophilicity and the chemical structure as well as their structure-activity relationships are discussed.

  1. Mixed Langmuir monolayers of an amphiphilic chromo-ionophore and the phospholipid DMPC

    Science.gov (United States)

    Sergeeva, T. I.; Gromov, S. P.; Vedernikov, A. I.; Kapichnikova, M. S.; Alfimov, M. V.; Möbius, D.; Zaitsev, S. Yu.

    2005-06-01

    The amphiphilic chromo-ionophore 2-[(1E,3E)-4-(2,3,5,6,8,9,11,12,14,15-decahydro-1,7,10,16,4,13-benzotetraoxadithiacyclooctadecin-18-yl)-1,3-butadienyl]-3-octadecyl-1,3-benzothiazol-3-ium perchlorate (AB211) forms mixed monolayers at the air-water interface with the phospholipid L-α-dimyristoylphosphatidylcholine (DMPC) as deduced from surface pressure-area and surface potential-area isotherms. In contrast to the behaviour of pure monolayers of AB211 on water, no association of the chromophores is observed by reflection spectroscopy. Upon compression of the mixed monolayer AB211:DMPC = 1:5, a re-orientation of the chromophores from flat to tilted is observed, presumably assisted by the stretching of the choline group of the phospholipid molecules acting a matrix.

  2. Patch Testing With Shoe Series In Suspected Cases Of Footwear Dermatitis

    Directory of Open Access Journals (Sweden)

    Eapen Bell Raj

    2001-01-01

    Full Text Available One hundred fifty nine patients with clinically suspected footwear dermatitis were patch tested to determine the frequency of positivity of common footwear antigens. Patch testing was done with 22 allergens of Shoe series (Chemotechnique Diagnostics AB Sweden extended with neomycin, gentamycin, soframycin, paraben, cresol and lanolin. Forty- two percent of patients was sensitive to footwear allergen(s whereas the overall positivity was 62%. Potassium dichromate. 2 mercapto- benzothiazole (MBT and nickel sulphate were the frequent sensitizers followed by gentamycin, neomycin, gluteraldehyde, formaldehyde, diphenyl guanidine, diphenyl thiourea, dibutyl thiourea, para-tertiary butyl phenol and 4 aminoazobenzene. Dorsa of feet was the commonest site. potassium dichromate sensitivity was higher in males and the history was not always helpful in incriminating the antigen.

  3. Synthesis and evaluation of new organic and phosphorous derivatives against ionizing radiation: study of the in vitro mechanism of action; Synthese et evaluation de nouveaux composes organiques et phosphores contre les effets des rayonnements ionisants. Etude de leur mecanisme d'action in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Prouillac, C

    2006-10-15

    This work falls under a research program. The aim was to synthesize new organic phosphorylated compounds having an interesting radio pharmacological activity without toxicity. That is why, we carried out the synthesis of new benzothiazole and thiadiazole N-substituted derivatives as thiols, amino thiols, acids thio-sulfonic and phosphoro thioates. All these compounds were characterized by NMR (proton, carbon, phosphorus, 2D), by mass spectrometry, elementary analyzes and for some of them by diffraction of x-rays. The activity of the majority of them was evaluated by in vitro tests. The experimental results were confirmed by theoretical study: the aim of D.F.T. calculation was the study of the mechanism of capture of the free radicals by our compounds. In addition, a study of relation structure activity (Q.S.A.R.) was carried out. Our results allow us to create a model making it possible to establish structure-activity relationship. (author)

  4. Color tunability in multilayer OLED based on DCM doped in a PVK matrix

    International Nuclear Information System (INIS)

    In this work, we present our achievements in color tunability in novel multilayer organic light-emitting diodes (OLEDs) based on DCM (4-(Dicyanomethylene)-2-methyl-6-[p- (dimethylamino)styryl]-4H-pyran) as red emitter doped in a composite PVK:TPD holetransporting layer, DPVBi (4,4'-Bis(2,2-diphenylvinyl)-1,1'-biphenyl) as a separate blue emitting layer, BAlq (aluminum bis(2-methyl-8-quinolinate)-4-phenylphenolate) as holeblocking layer and blue emitter at the same time, and Zn(BTz)2 (zinc bis(2-(2-hydroxyphenyl) benzothiazole)) as yellow emitter and electron transporting layer. By modification of the OLED structure and changing the DCM doped concentration in the matrix (in the range of 0 up to 5 %) the color tunability of OLED structures has been obtained. The efficiencies, luminance and chromaticity coordinates of the fabricated OLED structures have been specified

  5. Diaquabis(dimethyl sulfoxide-κOdisaccharinatocadmium

    Directory of Open Access Journals (Sweden)

    Fezile S. W. Potwana

    2011-11-01

    Full Text Available The title compound, [Cd(C7H4NO3S2(C2H6OS2(H2O2], contains a Cd2+ cation in an octahedral coordination environment. The metal atom is surrounded by the two different neutral ligands dimethyl sulfoxide (DMSO and water, each coordinating through the O atom. The anionic saccharinate (sac; 1,1,3-trioxo-2,3-dihydro-1λ6,2-benzothiazol-2-ide ligand coordinates through the N atom. Each of the three similar ligand pairs is in a trans configuration with respect to each other. The Cd atom lies on a crystallographic center of symmetry. The DMSO ligand coordinates through the lone pair of electrons on the O atom, as can be seen from the Cd—O—S bond angle of 123.96 (9°.

  6. Efectividad biológica de TCMTB para el control de la Costra Negra Rhizoctonia solani Kühn de la papa Solanum Tuberosum L., en la región de León, Guanajuato, México

    OpenAIRE

    Luis Pérez Moreno; José Orlando Castillo; Fernando Javier Cantú

    2001-01-01

    En la región de León, Guanajuato, México durante el ciclo verano-otoño 1998, se evaluó el fungicida 2-(Thiocyanomethylthio) benzothiazole (TCMTB) en dosis de 6, 8 y 10 litros por hectárea para el control del hongo del suelo Rhizoctonia solani Kühn. Se usó un diseño de bloques al azar, con cuatro repeticiones. Se evaluó el número de tallos emergidos, el efecto fitotóxico, los porcentajes de brotes y tallos dañados por R. solani, el rendimiento y calidad del tubérculo; finalmente, el porcentaje...

  7. Discovery of New Anti-Schistosomal Hits by Integration of QSAR-Based Virtual Screening and High Content Screening.

    Science.gov (United States)

    Neves, Bruno J; Dantas, Rafael F; Senger, Mario R; Melo-Filho, Cleber C; Valente, Walter C G; de Almeida, Ana C M; Rezende-Neto, João M; Lima, Elid F C; Paveley, Ross; Furnham, Nicholas; Muratov, Eugene; Kamentsky, Lee; Carpenter, Anne E; Braga, Rodolpho C; Silva-Junior, Floriano P; Andrade, Carolina Horta

    2016-08-11

    Schistosomiasis is a debilitating neglected tropical disease, caused by flatworms of Schistosoma genus. The treatment relies on a single drug, praziquantel (PZQ), making the discovery of new compounds extremely urgent. In this work, we integrated QSAR-based virtual screening (VS) of Schistosoma mansoni thioredoxin glutathione reductase (SmTGR) inhibitors and high content screening (HCS) aiming to discover new antischistosomal agents. Initially, binary QSAR models for inhibition of SmTGR were developed and validated using the Organization for Economic Co-operation and Development (OECD) guidance. Using these models, we prioritized 29 compounds for further testing in two HCS platforms based on image analysis of assay plates. Among them, 2-[2-(3-methyl-4-nitro-5-isoxazolyl)vinyl]pyridine and 2-(benzylsulfonyl)-1,3-benzothiazole, two compounds representing new chemical scaffolds have activity against schistosomula and adult worms at low micromolar concentrations and therefore represent promising antischistosomal hits for further hit-to-lead optimization. PMID:27396732

  8. Pure RGB Emissions Based on a White OLED Combined with Optical Colour Filters

    Institute of Scientific and Technical Information of China (English)

    WU Xiao-Ming; HUA Yu-Lin; WANG Zhao-Qi; YIN Shou-Gen; ZHENG Jia-Jin; DENG Jia-Chun; M. C. Petty

    2006-01-01

    @@ We report on a white organic light emitting device (OLED) with a single light emitting layer consisting of a greenish-white emitting host bis-(2-(2-hydroxyphenyl) benzothiazole)zinc (Zn(BTZ)2) and an orange-red dopant 5,6,11,12-tetraphenylnaphthacene (rubrene). The Commission Internationale De L'Eclairage (CIE) coordinates, external quantum efficiency, and brightness of the white OLED are (0.341, 0.334), 0.63% and 4000 Cd/m2 at the bias of 20 V, respectively. Pure red-green-blue (RGB) emissions have been successfully achieved from the white OLED combined well with several built-in optical colour filters (CFs). The CIE coordinates of the white mixture calculated in theory are very close to the coordinates of the white mixture which recorded with spectrophotometer in practice.

  9. 3-(Benzodioxan-2-ylmethoxy)-2,6-difluorobenzamides bearing hydrophobic substituents at the 7-position of the benzodioxane nucleus potently inhibit methicillin-resistant Sa and Mtb cell division.

    Science.gov (United States)

    Straniero, Valentina; Pallavicini, Marco; Chiodini, Giuseppe; Zanotto, Carlo; Volontè, Luca; Radaelli, Antonia; Bolchi, Cristiano; Fumagalli, Laura; Sanguinetti, Maurizio; Menchinelli, Giulia; Delogu, Giovanni; Battah, Basem; De Giuli Morghen, Carlo; Valoti, Ermanno

    2016-09-14

    Lipophilic substituents at benzodioxane C (7) of 3-(benzodioxan-2-ylmethoxy)-2,6-difluorobenzamide improve the antibacterial activity against methicillin-resistant Staphylococcus aureus strains to MIC values in the range of 0.2-2.5 μg/mL, whereas hydrophilic substituents at the same position and modifications at the benzodioxane substructure, excepting for replacement with 2-cromanyl, are deleterious. Some of the lead compounds also exhibit good activity against Mtb. Parallel SARs to those of 3-(2-benzothiazol-2-ylmethoxy)-2,6-difluorobenzamide, well known FtsZ inhibitor, and cells alterations typical of FtsZ inhibition indicate such a protein as the target of these potent antibacterial benzodioxane-benzamides. PMID:27191617

  10. New Fluorescence Probes for Biomolecules

    Directory of Open Access Journals (Sweden)

    Katarzyna Jurek

    2015-07-01

    Full Text Available Steady state fluorescence measurements have been used for the investigation of interaction between the bovine serum albumin (BSA and fluorescence probes: 3-hydroxy-2,4- bis[(3-methyl-1,3-benzoxazol-2(3H-ylidenemethyl]cyclobut-2-en-1-one (SQ6, 3-hydroxy- 2,4-bis[(3-methyl-1,3-benzothiazol-2(3H-ylidenemethyl]cyclobut-2-en-1-one (SQ7 and 3-hydroxy-2,4-bis[(1,3,3-trimethyl-1,3-dihydro-2H-indol-2-ylidenemethyl]cyclobut-2-en-1-one (SQ8. The binding constant between bovine serum albumin and squarine dyes has been determined by using both the Benesi-Hildebrand and Stern-Volmer equations. The negative value of free energy change indicates the existence of a spontaneous complexation process of BSA with squarine dyes.

  11. Noval 1-substituted-3,5-dimethyl-4-[(substituted phenyl diazenyl] pyrazole derivatives: Synthesis and pharmacological activity

    Directory of Open Access Journals (Sweden)

    Sabir Hussain

    2015-05-01

    Full Text Available Several-1-carbothioamide-3,5-dimethyl-4-[(substituted phenyl diazenyl] pyrazoles 2a–d, 1-(pyridine-4-ylcarbonyl-3,5-dimethyl-4-[(substituted phenyl diazenyl] pyrazoles 3a–d, 1-(5-chloro-6-fluoro-1,3-benzothiazole-2-ylthiocarbamoyl-3,5-dimethyl-4-[(substituted phenyl diazenyl] pyrazoles 4a–d and 1-[(1,2,4-triazole-4-yl carbothioamide]-3,5-dimethyl-4-[(substituted phenyl diazenyl] pyrazoles 5a–d were synthesized. The structures of the newly synthesized compounds were supported by IR, 1H NMR and mass spectral data. These compounds were investigated for their, anti-inflammatory, analgesic, ulcerogenic, lipid peroxidation, antibacterial and antifungal activities. Some of the synthesized compounds showed potent anti-inflammatory activity along with minimal ulcerogenic effect and lipid peroxidation, compared to ibuprofen and flurbiprofen. Some of the tested compounds also showed moderate antimicrobial activity against tested bacterial and fungal strains.

  12. Liberation of copper from amyloid plaques: making a risk factor useful for Alzheimer's disease treatment.

    Science.gov (United States)

    Geng, Jie; Li, Meng; Wu, Li; Ren, Jinsong; Qu, Xiaogang

    2012-11-01

    Alzheimer's disease (AD) is a complex multifactorial syndrome. Metal chelator and Aβ inhibitor are showing promise against AD. In this report, three small hybrid compounds (1, 2, and 3) have been designed and synthesized utilizing salicylaldehyde (SA) based Schiff bases as the chelators and benzothiazole (BT) as the recognition moiety for AD treatment. These conjugates can capture Cu(2+) from Aβ and become dimers upon Cu(2+) coordination and show high efficiency for both Cu(2+) elimination and Aβ assembly inhibition. Besides, the complexes have superoxide dismutase (SOD) activity and significant antioxidant capacity and are capable of decreasing intracellular reactive oxygen species (ROS) and increasing cell viability. All these results indicate that the multifunctional metal complexes which have Aβ specific recognition moiety and metal ion chelating elements show the potential for AD treatment. Therefore, our work will provide new insights into exploration of more potent amyloid inhibitors.

  13. Blood-brain transfer of Pittsburgh compound B in humans

    DEFF Research Database (Denmark)

    Gjedde, Albert; Aanerud, Joel; Braendgaard, Hans;

    2013-01-01

    In the labeled form, the Pittsburgh compound B (2-(4'-{N-methyl-[(11)C]}methyl-aminophenyl)-6-hydroxy-benzothiazole, [(11)C]PiB), is used as a biomarker for positron emission tomography (PET) of brain β-amyloid deposition in Alzheimer's disease (AD). The permeability of [(11)C]PiB in the blood......-brain barrier is held to be high but the permeability-surface area product and extraction fractions in patients or healthy volunteers are not known. We used PET to determine the clearance associated with the unidrectional blood-brain transfer of [(11)C]PiB and the corresponding cerebral blood flow rates in......-brain clearances of [(11)C]PiB in the patients....

  14. Benz[c,d]indolium-containing Monomethine Cyanine Dyes: Synthesis and Photophysical Properties

    Directory of Open Access Journals (Sweden)

    Eduardo Soriano

    2015-12-01

    Full Text Available Asymmetric monomethine cyanines have been extensively used as probes for nucleic acids among other biological systems. Herein we report the synthesis of seven monomethine cyanine dyes that have been successfully prepared with various heterocyclic moieties such as quinoline, benzoxazole, benzothiazole, dimethyl indole, and benz[e]indole adjoining benz[c,d]indol-1-ium, which was found to directly influence their optical and energy profiles. In this study the optical properties vs. structural changes were investigated using nuclear magnetic resonance and computational approaches. The twisted conformation unique to monomethine cyanines was exploited in DNA binding studies where the newly designed sensor displayed an increase in fluorescence when bound in the DNA grooves compared to the unbound form.

  15. Molecular indicators for pollution source identification in marine and terrestrial water of the industrial area of Kavala city, North Greece

    Energy Technology Data Exchange (ETDEWEB)

    Grigoriadou, A. [Department of Mineralogy-Petrology-Economic Geology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)], E-mail: grigoriadou@lek.rwth-aachen.de; Schwarzbauer, J. [Institute of Geology and Geochemistry of Petroleum and Coal, Aachen University of Technology, Lochnerstrasse 4-20, 52056 Aachen (Germany)], E-mail: schwarzbauer@lek.rwth-aachen.de; Georgakopoulos, A. [Department of Mineralogy-Petrology-Economic Geology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)], E-mail: ageorgak@geo.auth.gr

    2008-01-15

    Eight terrestrial and four marine water samples were collected from the industrial section of the city of Kavala in northern Greece to determine the occurrence and distribution of organic contaminants, as well as to identify the molecular markers of different emission sources. The samples were analyzed by means of non-target screening analyses. The analytical procedure included a sequential extraction of the samples, GC-FID, GC/MS analyses, and additional quantitative analyses of selected pollutants. The results show a wide variety of compounds including halogenated compounds, technical additives and metabolites, phosphates, phthalates, benzothiazoles, etc. A close relationship between many of the contaminants and their emission sources was determined based on their molecular structures and information on technical applications. - Organic contaminants were used to estimate the state of the pollution and to identify sources in an area impacted by numerous anthropogenic activities.

  16. Optical and Thermal Properties of Nickel-Azo Dyes for Digital Versatile Disc-Recordable

    Institute of Scientific and Technical Information of China (English)

    魏斌; 吴谊群; 顾冬红; 干福熹

    2003-01-01

    We investigate the absorption spectra, optical constants and thermal decomposition as well as red-light (650 nm)static recording properties of three novel nickel-azo dye filrns based on 4-methylthiazole, benzothiazole and 6-methylbenzothiazole. Particularly, we obtain the nickel-azo complex film based on 4-methylthiazole, peaking at 562nm and 613nm, with higher refractive index (n = 2.46) and lower extinction coefficient (k = 0.18) at the wavelength 650nm and a sharp threshold of thermal decomposition at 330℃. The results of the static optical recording test of this dye film indicate that high reflectivity contrast of 51% can be observed at a laser writing power of 5.9mW and pulse width of 350ns. These results imply that the nickel-azo complex based on 4-methylthiazole is a promising candidate for a recording medium of digital versatile disc-recordable.

  17. Electrospray Ionization Mass Spectra of Dipeptide Derivatives

    Institute of Scientific and Technical Information of China (English)

    LUO, Zaigang; ZENG, Chengchu; YANG, Daoshan; HUANG, Yali; WANG, Fang; DU, Hongguang; HU, Liming

    2009-01-01

    Based on the structure of the HIV integrase core domain, dipeptide derivatives, as a type of HIV integrase in- hibitor, were synthesized, and their fragmentation pathways were investigated by electrospray ionization mass spec- trometry (ESI-MSN) in conjunction with tandem mass spectrometry (MS/MS). In order to better understand the fragmentation pathways, the MS2 and MS3 spectra of the title compound were obtained. The main fragmentation pathways occur by the cleavage of the C-CO bonds between N-(benzothiazol-2-yl)aminocarbonyl and methylene, NH-CO bonds between the NH groups and carbonyl groups. Electrospray ionization was proven to be a good method for the structural characterization and identification of this kind of compound.

  18. Efficient Synthesis of 2-Amino-6-Arylbenzothiazoles via Pd(0 Suzuki Cross Coupling Reactions: Potent Urease Enzyme Inhibition and Nitric Oxide Scavenging Activities of the Products

    Directory of Open Access Journals (Sweden)

    Md. Saiful Islam

    2013-07-01

    Full Text Available In general, benzothiazole derivatives have attracted great interest due to thier pharmaceutical and biological importance. New 2-amino-6-arylbenzothiazoles were synthesized in moderate to excellent yields via Suzuki cross coupling reactions using various aryl boronic acids and aryl boronic acid pinacol esters and the antiurease and nitric oxide (NO scavenging activity of the products were also examined. The most active compound concerning urease enzyme inhibition was 6-phenylbenzo[d]thiazole-2-amine 3e, with an IC50 value of 26.35 µg/mL. Compound 3c, 6-(4-methoxyphenyl benzo[d]thiazole-2-amine, exhibited the highest nitric oxide percentage scavenging at 100µg/mL.

  19. Synthesis and evaluation of new organic and phosphorous derivatives against ionizing radiation: study of the in vitro mechanism of action

    International Nuclear Information System (INIS)

    This work falls under a research program. The aim was to synthesize new organic phosphorylated compounds having an interesting radio pharmacological activity without toxicity. That is why, we carried out the synthesis of new benzothiazole and thiadiazole N-substituted derivatives as thiols, amino thiols, acids thio-sulfonic and phosphoro thioates. All these compounds were characterized by NMR (proton, carbon, phosphorus, 2D), by mass spectrometry, elementary analyzes and for some of them by diffraction of x-rays. The activity of the majority of them was evaluated by in vitro tests. The experimental results were confirmed by theoretical study: the aim of D.F.T. calculation was the study of the mechanism of capture of the free radicals by our compounds. In addition, a study of relation structure activity (Q.S.A.R.) was carried out. Our results allow us to create a model making it possible to establish structure-activity relationship. (author)

  20. Accumulation of 19 environmental phenolic and xenobiotic heterocyclic aromatic compounds in human adipose tissue.

    Science.gov (United States)

    Wang, Lei; Asimakopoulos, Alexandros G; Kannan, Kurunthachalam

    2015-05-01

    The extensive use of environmental phenols (e.g., bisphenol A) and heterocyclic aromatic compounds (e.g., benzothiazole) in consumer products as well as widespread exposure of humans to these compounds have been well documented. Biomonitoring studies have used urinary measurements to assess exposures, based on the assumption that these chemicals are metabolized and eliminated in urine. Despite the fact that some of these chemicals are moderately lipophilic, the extent of their accumulation in adipose fat tissues has not been convincingly demonstrated. In this study, human adipose fat samples (N=20) collected from New York City, USA, were analyzed for the presence of environmental phenols, including bisphenol A (BPA), benzophenone-3 (BP-3), triclosan (TCS), and parabens, as well as heterocyclic aromatic compounds, including benzotriazole (BTR), benzothiazole (BTH), and their derivatives. BPA and TCS were frequently detected in adipose tissues at concentrations (geometric mean [GM]: 3.95ng/g wet wt for BPA and 7.21ng/g wet wt for TCS) similar to or below the values reported for human urine. High concentrations of BP-3 were found in human adipose tissues (GM: 43.4; maximum: 4940ng/g wet wt) and a positive correlation between BP-3 concentrations and donor's age was observed. The metabolite of parabens, p-hydroxybenzoic acid (p-HB), also was found at elevated levels (GM: 4160; max.: 17,400ng/g wet wt) and a positive correlation between donor's age and sum concentration of parabens and p-HB were found. The GM concentrations of BTR and BTH in human adipose tissues were below 1ng/g, although the methylated forms of BTR (i.e., TTR and XTR) and the hydrated form of BTH (i.e., 2-OH-BTH) were frequently detected in adipose samples, indicating widespread exposure to these compounds. Our results suggest that adipose tissue is an important repository for BP-3 and parabens, including p-HB, in the human body.

  1. 新型查尔酮衍生物的合成及酪氨酸酶活性%Synthesis and Activity on Tyrosinase of Novel Chalcone Derivatives

    Institute of Scientific and Technical Information of China (English)

    牛超; 李根; 买迪娜; 阿吉艾克拜尔·艾萨

    2014-01-01

    合成了8个新型含苯并噻唑环的查尔酮衍生物及8个酰胺查尔酮,并对化合物的结构进行了表征.生物活性测试结果表明,化合物4d,4h,5d,7b 和7d 表现出一定的酪氨酸酶激动活性,其中化合物7d 对酪氨酸酶的活性最好,其 EC50=9.6μmol/ L,优于阳性对照药8-MOP(EC50=14.8μmol/ L).%Ver-nohia anthelmintica L was endemic plant in Xinjiang, which was often used in the treatment of Vitiligo. It was believed that the chalcone compounds of Ver-nohia anthelmintica L played an important role in this treatment. Since it may activate tyrosinase and improve the melanin production, many chalcone com-pounds and derivatives were described as potential inhibitor on tyrosinase which may act as skin lightening and whitening agents. However, chalcones which showed activator effect were seldom reported. In order to search for chalcones with high activities on tyrosinase, eight novel chalcone derivatives containing benzothiazole and eight amide-derived chalcones were synthesized in this work. All the compounds were identified by 1 H NMR, 13 C NMR, IR, HRMS and evaluated their activator effect on tyrosinase by measuring the oxidation rate of L-dopa. Compared with the reference drug 8-methoxypsoralen, compounds 4d, 4h, 5d, 7b and 7d showed some activator effect on tyrosinase. Amomg them, compound 7d demonstrated more potent activity with EC50 =9. 6 μmol/ L than 8-methoxypsoralen, which EC50 value was 14. 8 μmol/ L. Further structural modification of this novel chalcones containing benzothiazole will be required for improving the solubility of them.

  2. Improving the Performances of Random Copolymer Based Organic Solar Cells by Adjusting the Film Features of Active Layers Using Mixed Solvents

    Directory of Open Access Journals (Sweden)

    Xiangwei Zhu

    2015-12-01

    Full Text Available A novel random copolymer based on donor–acceptor type polymers containing benzodithiophene and dithienosilole as donors and benzothiazole and diketopyrrolopyrrole as acceptors was designed and synthesized by Stille copolymerization, and their optical, electrochemical, charge transport, and photovoltaic properties were investigated. This copolymer with high molecular weight exhibited broad and strong absorption covering the spectra range from 500 to 800 nm with absorption maxima at around 750 nm, which would be very conducive to obtaining large short-circuits current densities. Unlike the general approach using single solvent to prepare the active layer film, mixed solvents were introduced to change the film feature and improve the morphology of the active layer, which lead to a significant improvement of the power conversion efficiency. These results indicate that constructing random copolymer with multiple donor and acceptor monomers and choosing proper mixed solvents to change the characteristics of the film is a very promising way for manufacturing organic solar cells with large current density and high power conversion efficiency.

  3. Application of toxicity identification evaluation procedure to toxic industrial effluent in South Korea.

    Science.gov (United States)

    Ra, Jin-Sung; Jeong, Tae-Yong; Lee, Sun-Hong; Kim, Sang Don

    2016-01-01

    Toxicity identification evaluation (TIE) was applied to the effluent from a pharmaceutical industrial complex, following the US EPA TIE guidelines. The whole effluent toxicity (WET) test found toxicity greater than 16toxic units (TU) in the effluent. Dissolved non-polar organic compounds were identified as the major contributor to the observed toxicity in the TIE manipulations in phases I and II. Among the 48 organic compounds identified, three compounds (i.e., acetophenone, benzoimide, and benzothiazole) were related to the pharmaceutical production procedure; however, no contribution to toxicity was predicted in the compounds. The results of the ECOSAR model, which predicts toxicity, indicated that the alkane compounds caused significant toxicity in the effluent. The toxicity test and heavy metal analysis, which used IC and ICP/MS, identified that particulate and heavy metals, such as Cu and Zn, contributed to the remaining toxicity, except dissolved organics. The results showed the applicability of the TIE method for predicting regional effluents produced by the industrial pharmaceutical complex in this study. Although the location was assumed to be affected by discharge of pharmaceutical related compounds in the river, no correlations were observed in the study. Based on the results, advanced treatment processes, such as activated carbon adsorption, are recommended for the wastewater treatment process in this location.

  4. Dynamic changes in PET amyloid and FDG imaging at different stages of Alzheimer's disease.

    Science.gov (United States)

    Kadir, Ahmadul; Almkvist, Ove; Forsberg, Anton; Wall, Anders; Engler, Henry; Långström, Bengt; Nordberg, Agneta

    2012-01-01

    In this study 5 patients with mild cognitive impairment (MCI) and 9 Alzheimer's disease (AD) patients underwent respectively 3- and 5-year follow-up positron emission tomography (PET) studies with N-methyl [(11)C] 2-(4-methylaminophenyl)-6-hydroxy-benzothiazole ((11)C-PIB) and (18)F-fluorodeoxyglucose ((18)F-FDG) to understand the time courses in AD disease processes. Significant increase in PIB retention as well as decrease in regional cerebral metabolic rate of glucose (rCMRglc) was observed at group level in the MCI patients while no significant change was observed in cognitive function. At group level the AD patients showed unchanged high PIB retention at 5-year follow-up compared with baseline. At the individual level, increased, stable, and decreased PIB retention were observed while disease progression was reflected in significant decrease in rCMRglc and cognition. In conclusion, after a long-term follow-up with PET, we observed an increase in fibrillar amyloid load in MCI patients followed by more stable level in clinical AD patients. The rCMRglc starts to decline in MCI patients and became more pronounced in clinical stage which related to continuous decline in cognition.

  5. Pramipexole inhibits MPTP toxicity in mice by dopamine D3 receptor dependent and independent mechanisms.

    Science.gov (United States)

    Ramirez, Andres D; Wong, Stephen K-F; Menniti, Frank S

    2003-08-15

    The role of dopamine D3 receptors was investigated in mediating the neuroprotective effect of the dopamine D2/D3 receptor agonist (S)-2-amino-4,5,6,7-tetrahydro-6-propylamine-benzothiazole (pramipexole) in vivo. Pramipexole retained the ability to inhibit 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced dopamine depletion in mice in which the dopamine D3 receptor had been deleted. However, the neuroprotective efficacy was reduced in the dopamine D3 receptor-deleted mice compared to that in littermates expressing the wildtype receptor. Furthermore, the dopamine D3 receptor selective antagonist 2-(3-[4-(2-tert-butyl-6-trifluoromethyl-4-pyrimidinyl)-1-piperazinyl]propylthio)-4-pyrimidinol (A-437203) partially inhibited the neuroprotective effect of pramipexole in dopamine D3 receptor expressing mice but not in receptor-deleted mice. These results indicate that pramipexole protects dopamine neurons from MPTP-induced toxicity by mechanisms that are both dependent and independent of an interaction with dopamine D3 receptors. PMID:12954356

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

    Science.gov (United States)

    Erdemir, Serkan; Kocyigit, Ozcan

    2016-09-01

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

  7. Identification of volatile markers in potato brown rot and ring rot by combined GC-MS and PTR-MS techniques: study on in vitro and in vivo samples.

    Science.gov (United States)

    Blasioli, Sonia; Biondi, Enrico; Samudrala, Devasena; Spinelli, Francesco; Cellini, Antonio; Bertaccini, Assunta; Cristescu, Simona M; Braschi, Ilaria

    2014-01-15

    Ralstonia solanacearum (Rs) and Clavibacter michiganensis subsp. sepedonicus (Cms) are the bacterial causal agents of potato brown and ring rot, respectively, and are included in the A2 list of quarantine pathogens in Europe. Identification by GC-MS analysis of volatile organic compounds from Rs or Cms cultured on different nutrient media was performed. GC-MS and PTR-MS analysis were carried out also on unwounded potato tubers infected with the same pathogens. Infected tubers were produced by experimental inoculations of the plants. In in vitro experiments, Rs or Cms emitted volatile compounds, part of which were specific disease markers of potato (2-propanol and 3-methylbutanoic acid), mainly originating from bacterial metabolism (i.e., amino acid degradation, carbohydrate and fatty acid oxidation). In potato tubers, pathogen metabolism modified the volatile compound pattern emitted from healthy samples. Both bacteria seem to accelerate metabolic processes ongoing in potatoes and, in the case of Rs, disease markers (1-hepten-3-ol, 3,6-dimethyl-3-octanone, 3-ethyl-3-methylpentane, 1-chloroctane, and benzothiazole) were identified. PMID:24313381

  8. White organic light-emitting devices using Zn(BTZ)2 doped with Rubrene as emitting layer

    Institute of Scientific and Technical Information of China (English)

    ZHENG Jiajin; HUA Yulin; YIN Shougen; FENG Xiulan; WU Xiaoming; SUN Yuanyuan; LI Yongfang; YANG Chunhe; SHUAI Zhigang

    2005-01-01

    Zn(BTZ)2 was synthesized from the complex reaction between zinc acetate dihydrate and 2-(2- hydroxyphenyl) benzothiazolate. Then Zn(BTZ)2 was used as main light-emitting material doped with different amounts of fluorescent dye Rubrene and fabricated a series of white organic light emitting devices. The configurations were as follows: ITO/PVK:TPD/Zn(BTZ)2:Rubrene/Al. The doping concentration of Rubrene in Zn(BTZ)2 was 1.2%, 0.12%, 0.08% and 0.05%, respectively. According to the EL spectra and CIE coordinates of the above devices, the optimum doping concentration (0.05%, weight percent) had been determined. The steady and bright white light emitting of the device with 0.05% doping concentration had been obtained, and the white emission covered a wide range of driving voltage (10-22.5 V). The CIE coordinates were (x=0.341, y=0.334) at the driving voltage of 20 V, which was very close to the equi-energy point (x=0.333, y=0.333), and the corresponding luminance and external quantum efficiency were 4048 Cd/m2 and 0.63% (4.05 Cd/A), respectively. Lastly, we also discussed the emitting mechanisms of the material and the devices.

  9. Synthesis of new condensed coumarin derivatives

    Directory of Open Access Journals (Sweden)

    Dekić Stojadin V.

    2007-01-01

    Full Text Available Reactions of 4-chloro-2-oxo-2H-chromene-3-carbonitrile (1 with 4-methylpyridin- 2-ylamine (2 and 6-methoxy-benzothiazol-2-ylamine (3 in acetonitrile containing a catalytic amount of triethylamine gave the new coumarin derivatives 7-imino-10-methyl-7H- 5-oxa-7a,12-diaza-benzo[a]anthracen-6-one (4 and 7-imino-10-methoxy-7H-5-oxa-12- thia-7a,13-diaza-indeno[1,2-b]phenanthren-6-one (5 in 52 and 39% yields, respectively. The novel compounds were subjected to acid hydrolysis giving the corresponding oxoderivatives 10-methyl-5-oxa-7a,12-diaza-benzo[a]anthracene-6,7-dione (6 and 10- methoxy-5-oxa-12-thia-7a,13-diaza-indeno[1,2-b]phenanthrene-6,7-dione (7 in 64 and 58% yields, respectively. The structural assignments of the synthesized compounds were based on elemental analyses, IR and proton NMR spectra. .

  10. Effect of inserting of thin Rubrene layer on performance of Organic Light-Emitting Diodes based on Zn(BTz){sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Tomova, R L; Petrova, P K; Stoycheva-Topalova, R T, E-mail: reni@clf.bas.b [Institute of optical materials and technologies ' Acad. J. Malinowski' , Bulgarian Academy of Sciences, ' Acad. G. Bonchev' str. bl. 109, 1113 Sofia (Bulgaria)

    2010-11-01

    Organic light-emitting diodes (OLEDs) with improved performances are fabricated using a thin (1 nm) yellow-emitting layer of 5,6,11,12-tetraphenylnaphthacene (Rubrene) inserted at different position in green emitting electroluminescent (EL) layer of bis-(2-(2-hydroxyphenyl) benzothiazole)zinc (Zn(BTz){sub 2}) in configuration: ITO/PVK:TPD/ Zn(BTz){sub 2} (x nm)/ Rubrene (1 nm)/ Zn(BTz){sub 2} (75-x nm)/Al, where PVK:TPD is a hole transporting layer of N, N'-bis(3-methylphenyl)-N, N'-diphenylbenzidine (TPD) incorporated in poly(N-vinylcarbazole) (PVK) matrix and Al is a cathode. EL spectra predominantly influenced by Rubrene emission when the doping layer is close to (PVK:TPD)/ Zn(BTz){sub 2} (x{yields} 0-15 nm) and to Zn(BTz){sub 2}/Al (x{yields} 70-75 nm) interfaces and shift toward emission of Zn(BTz){sub 2} increasing the distance of Rubrene from both interfaces (x{yields}35 nm). The same dependence of the EL efficiency on the position of the doping Rubrene layer in the OLED structure was found.

  11. Synthesis, DNA/HSA Interaction Spectroscopic Studies and In Vitro Cytotoxicity of a New Mixed Ligand Cu(II) Complex.

    Science.gov (United States)

    Gan, Qian; Fu, Xiabing; Chen, Weijiang; Xiong, Yahong; Fu, Yinlian; Chen, Shi; Le, Xueyi

    2016-05-01

    A new mixed ligand copper(II)-dipeptide complex with 2-(2'-pyridyl)benzothiazole (pbt), [Cu(Gly-L-leu)(pbt)(H2O)]·ClO4 (Gly-L-leu = Glycyl-L-leucine anion) was synthesized and characterized by various physico-chemical means. The DNA binding and cleavage properties of the complex investigated by viscosity, agarose gel electrophoresis and multi-spectroscopic techniques (UV, circular dichroism (CD) and fluorescence) showed that the complex was bound to CT-DNA through intercalation mode with moderate binding constant (K b = 3.132 × 10(4) M(-1)), and cleaved pBR322 DNA efficiently (~ 5 μM) in the presence of Vc, probably via an oxidative mechanism induced by •OH. Additionally, the interaction of the complex with human serum albumin (HSA) was explored by UV-visible, CD, fluorescence, synchronous fluorescence and 3D fluorescence spectroscopy. The complex exhibits desired affinity to HSA through hydrophobic interaction. Moreover, the cytotoxicity of the complex against three human carcinoma cell lines (HeLa, HepG2 and A549) was evaluated by MTT assay, which showed that the complex had effective cytotoxicity and higher inhibition toward A549 cell lines with IC50 of 38.0 ± 3.2 μM.

  12. Crystal structures of nitrato-(2-[2-(1-pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo) aquacopper and chloro-(2-[2-phenyl(pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo) copper

    Energy Technology Data Exchange (ETDEWEB)

    Chumakov, Yu. M. [Academy of Sciences of Moldova, Institute of Applied Physics (Moldova, Republic of); Paholnitcaia, A. Yu. [State University of Moldova (Moldova, Republic of); Petrenko, P. A. [Academy of Sciences of Moldova, Institute of Applied Physics (Moldova, Republic of); Tsapkov, V. I., E-mail: vtsapkov@gmail.com [State University of Moldova (Moldova, Republic of); Poirier, D. [Centre Hospitalier Universitaire de Quebec (Canada); Gulea, A. P. [State University of Moldova (Moldova, Republic of)

    2015-01-15

    Two crystal modifications of nitrato-(2-[2-(1-pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo) aquacopper (I and II) and two modifications of chloro-(2-[2-phenyl(pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo) copper (III and IV) have been synthesized and studied by X-ray diffraction. In structures I and II, the copper atoms coordinate a monodeprotonated molecule of the organic ligand, nitrate ions, and a water molecule. In crystals of I, the complexes are monomeric, whereas complexes II are linked via nitrate ions to form polymeric chains. In both structures the coordination polyhedron of the copper atom can be described as a distorted tetragonal bipyramid—(4 + 1 + 1) in I and (4 + 2) in II. These coordination polyherdra have different compositions. In structures III and IV, the metal atoms coordinate a monodeprotonated (2-[2-phenyl(pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazole molecule and chloride ions. In III the complex-forming ion has square-planar coordination geometry, whereas structure IV consists of centrosymmetric dimers with two bridging chlorine atoms. It was found that nitrato-(2-[2-(1-pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo) aquacopper possesses antitumor activity.

  13. trans-thionate derivatives of Pt(II) and Pd(II) with water-soluble phosphane PTA and DAPTA ligands: antiproliferative activity against human ovarian cancer cell lines.

    Science.gov (United States)

    Guerrero, Elena; Miranda, Susana; Lüttenberg, Sebastian; Fröhlich, Nils; Koenen, Jan-Moritz; Mohr, Fabian; Cerrada, Elena; Laguna, Mariano; Mendía, Aránzazu

    2013-06-01

    A series of PTA and DAPTA platinum(II) and palladium(II) thionate complexes of the type trans-[M(SN)2P2] were prepared from the reaction of cis-[MCl2P2] [M = Pt, Pd; P = PTA (1,3,5-triaza-7-phosphaadamantane), DAPTA (3,7-diacetyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane)] with the in situ generated sodium salts of the heterocyclic thiones S-m-methylpyrimidine-2-thione, S-4,6-dimethylpyrimidine-2-thione, S-4,6-dihydroxypyrimidine-2-thione, benzothiazole-2-thione, benzoxazole-2-thione, S-1,3,4,-thiadiazole-2-thione, S-4,5-H-thiazolan-2-thione, and S-pyrimidine-4(1H)-one-2-thione. The X-ray structures of six of the compounds confirm the trans disposition and, only in the case of [Pd2Cl2(S-pyrimidine-4(1H)-one-2-thionate)2(PTA)2], a dinuclear structure with a Pd-Pd distance of 3.0265(14)Å was observed. In vitro cytotoxicities against human ovarian cancer cell lines A2780 and A2780cisR were evaluated for ten complexes showing a high inhibition of cellular growth with a comparable inhibitory potency (IC50) against A2780 cells to that of cisplatin. Notably, the compounds also show significant (up to 7-fold higher) activity in cisplatin-resistant A2780cisR cell lines. PMID:23692403

  14. Specific capture of the hydrolysate on magnetic beads for sensitive detecting plant vacuolar processing enzyme activity.

    Science.gov (United States)

    Zhou, Jun; Cheng, Meng; Zeng, Lizhang; Liu, Weipeng; Zhang, Tao; Xing, Da

    2016-05-15

    Conventional plant protease detection always suffers from high background interference caused by the complex coloring metabolites in plant cells. In this study, a bio-modified magnetic beads-based strategy was developed for sensitive and quantitative detection of plant vacuolar processing enzyme (VPE) activity. Cleavage of the peptide substrate (ESENCRK-FITC) after asparagine residue by VPE resulted in the 2-cyano-6-amino-benzothiazole (CABT)-functionalized magnetic beads capture of the severed substrate CRK-FITC via a condensation reaction between CABT and cysteine (Cys). The catalytic activity was subsequently obtained by the confocal microscopy imaging and flow cytometry quantitative analysis. The sensor system integrated advantages of (i) the high efficient enrichment and separation capabilities of magnetic beads and (ii) the catalyst-free properties of the CABT-Cys condensation reaction. It exhibited a linear relationship between the fluorescence signal and the concentration of severed substrate in the range of 10-600 pM. The practical results showed that, compared with normal growth conditions, VPE activity was increased by 2.7-fold (307.2 ± 25.3 μM min(-1)g(-1)) upon cadmium toxicity stress. This platform effectively overcame the coloring metabolites-caused background interference, showing fine applicability for the detection of VPE activity in real samples. The strategy offers great sensitivity and may be further extended to other protease activity detection. PMID:26797250

  15. Bis(propane-1,3-diaminedisaccharinatonickel(II

    Directory of Open Access Journals (Sweden)

    Gökhan Kaştaş

    2012-04-01

    Full Text Available In the title complex, [Ni(C7H4NO3S2(C3H10N22] or [Ni(sac2(pen2] (sac = saccharinate or 1,1,3-trioxo-2,3-dihydro-1λ6,2-benzothiazol-2-ide and pen = propane-1,3-diamine, the NiII ion sits on an inversion center, being coordinated by two N atoms of the sac ligands, which occupy trans positions, and four N atoms of the bidentate pen ligands to define a distorted octahedral geometry. The pen ligands chelate the metal ion, forming a six-membered ring which adopts a half-chair conformation, while the sac ligands adopt the most common coordination mode. The crystal packing is stabilized by N—H...O hydrogen bonds, which form a one-dimensional network along [010]. It is also supported by an N—H...S hydrogen bond between the amine group of the pen ligand and the sulfonyl group of the sac ligand.

  16. Bis(dimethyl sulfoxide-κObis(saccharinato-κNzinc(II

    Directory of Open Access Journals (Sweden)

    Fezile S. W. Potwana

    2011-12-01

    Full Text Available The title compound, [Zn(C7H4N2O3S2(C2H6OS2], is a neutral four-coordinate complex with a tetrahedral geometry. The metal atom is surrounded by the two dimethyl sulfoxide (DMSO ligands, each coordinating through the O atom, and two anionic saccharinate (1,1,3-trioxo-2,3-dihydro-1λ6,2-benzothiazol-2-ide ligands coordinating through the N atom. The tetrahedral geometry is slightly distorted as is evident from the N—Zn—N bond angle of 113.85 (6°, the O—Zn—O bond angle of 98.92 (6° and O—Zn—N bond angles of 116.96 (6 and 103.93 (6°. The Zn—N bond lengths are 1.9742 (15 and 2.0025 (16 Å. The Zn—O bond lengths are 1.9806 (14 Å and 1.9468 (14 Å. The DMSO ligand coordinates through the lone pair of electrons on the O atom, as can be seen from the Zn—O—S bond angle of 131.30 (8°.

  17. Synthesis of Two Novel Additives and Study of Their Tribological Properties in Rapeseed Oil

    Institute of Scientific and Technical Information of China (English)

    Zhou Maolin; Li Fenfang; Zeng Xiaojun; Fan Chengkai

    2007-01-01

    Two novel ashless additives-benzothiazole derivatives containing boron and chlorine,OBC and BBC,were synthesized.The tribological performances of OBC and BBC at different mass ratios as additives in rapeseed oil(RO)were examined on a four-ball machine.The worn surfaces of the lower steel balls lubricated by oil samples were analyzed by means of scanning electron microscopy (SEM).The test results showed that OBC and BBC had good solubility in the base oil,and could effectively increase the load-carrying capacity of the base Oil.The maximum non-seizure load of oil sample containing 1.5 m% BBCwas 1117N.which was 2.3 times as much as that of the base oil.Both OBC and BBC could improve the anti-wear and corrosion inhibiting performance and thermal stability of the base oil,whose initial decomposition temperatures was above 350℃.However,OBC and BBC at different concentrations could increase the friction coefficient of the base oil.The SEM morphology of steel balls lubricated by oil samples containing 1.5 m%additives seemed to be more uniform and smoother than that of the base oil,and the scars formed were very shallow.

  18. Diaquabis(dimethyl sulfoxide-κObis(saccharinato-κNcobalt(II

    Directory of Open Access Journals (Sweden)

    Fezile S. W. Potwana

    2011-12-01

    Full Text Available The title complex, [Co(C7H4NO3S2(C2H6OS2(H2O2], contains a Co2+ cation in an octahedral coordination environment. The metal atom is surrounded by two different neutral ligands, namely dimethylsulfoxide (DMSO and water, each coordinating through the O atom. The anionic saccharinate (sac; 1,1,3-trioxo-2,3-dihydro-1λ6,2-benzothiazol-2-ide ligand coordinates through the N atom. Each of the three similar ligand pairs is in a trans configuration with respect to each other. The Co atom lies on a crystallographic center of symmetry and the octahedral geometry is not significantly distorted. A short O—H...O hydrogen bond is present between a water H atom and the ketone O atom; two longer hydrogen bonds (intra- and intermolecular are also present between a water H and a sulfonic O atom, forming a supramolecular assembly through head-to-tail aggregation between adjacent complexes.

  19. Worldwide occurrence and effects of antifouling paint booster biocides in the aquatic environment: a review.

    Science.gov (United States)

    Konstantinou, I K; Albanis, T A

    2004-04-01

    Organic booster biocides were recently introduced as alternatives to organotin compounds in antifouling products, after restrictions imposed on the use of tributyltin (TBT) in 1987. Replacement products are generally based on copper metal oxides and organic biocides. This ban has led to an increase in alternative coating products containing the above biocides. The most commonly used biocides in antifouling paints are: Irgarol 1051, diuron, Sea-nine 211, dichlofluanid, chlorothalonil, zinc pyrithione, TCMS (2,3,3,6-tetrachloro-4-methylsulfonyl) pyridine, TCMTB [2-(thiocyanomethylthio) benzothiazole], and zineb. Since 1993, several studies have demonstrated the presence of these biocides in European coastal environment as a result of their increased use. More recently, the presence of these biocides was also revealed in waters from Japan, United States, Singapore, Australia and Bermuda. This paper reviews the currently available data on the occurrence of these biocides in the aquatic environment. Some data dealing with the environmental fate, partitioning, behaviour and risk assessment of antifouling paint booster biocides are also reported in order to discuss the detected levels of contamination. PMID:14749112

  20. Recognizing acute health effects of substitute fungicides: are first-aid reports effective?

    Science.gov (United States)

    Teschke, K; Hertzman, C; Wiens, M; Dimich-Ward, H; Hershler, R; Ostry, A; Kelly, S J

    1992-01-01

    Recently, many British Columbia sawmills stopped using traditional chlorophenate anti-sapstain fungicides and substituted 2-(thiocyanomethylthio) benzothiazole (TCMTB) and copper-8-quinolinolate (Copper 8). We conducted a cross-sectional study with two aims: to ascertain which acute health effects, if any, were associated with the use of the substitute fungicides; and to determine the effectiveness of first-aid records as a means of detecting acute health outcomes. Workers in five coastal sawmills were asked to complete a self-administered questionnaire about symptoms considered potentially related and unrelated to fungicide exposure, and about injuries commonly reported in sawmills. In addition, we collected first-aid records from the mills, and asked senior workers to estimate the duration of exposure to fungicides for each job. Symptoms found to be consistently elevated in TCMTB mills included dry skin around the eyes, blood-stained mucus from the nose, nose bleed, peeling skin, burning or itching skin, and skin redness or rash. No symptoms were consistently elevated in the Copper 8 mills. Symptoms related to TCMTB exposure were recorded only 12 times in first-aid logs during the study period (versus 335 questionnaire self-reports). This low symptom-recording frequency may be a function of established patterns of first-aid use in which illness symptoms are reported less frequently than injuries. PMID:1585948

  1. The Odra project 'Interdisciplinary German-Polish studies about the behavior of pollutants in the Odra-system'. Subproject 2: Trace analysis of organic pollutants in the Odra-system. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Francke, W.; Franke, S.; Heinzel, N.; Meyer, C.; Specht, M.

    2001-07-01

    Non target screening results of IOP-Subproject 2: 'Trace Analysis of Organic Pollutants in the Odra-System' elucidate the requirement of monitoring a large number of synthetic organic compounds which were identified in the Odra-system with the objective to establish a basis for the systematic control of their emissions. The Odra-system's water and sediment pollution can be characterized by the following results: Sediments are frequently polluted by polycyclic aromatic hydrocarbons and in rare cases only by additional 'classic' environmental pollutants, chlorinated hydrocarbons, as PCB, DDT-group compounds, and HCH. A number of anthropogenic marker compounds, as phenylalkanes, alkylphenols, alkylphenolethoxylates, and faecal steroides are present, that can be useful for the identification of (municipal and rural) emission sources. 'Modern' pesticides, mainly a small number of herbicides as well as pharmaceuticals are contaminants of the Odra water. Additionally present are industrial chemicals and waste products, introduced by direct emissions into the Odra-system. Within the chemical groups of benzothiazoles, thio- and dithiocarbamates, sulfones and sulfonic acid amides, a variety of organic compounds was identified for the first time in the aquatic environment. The ecotoxicological impact of these substances is not known. Mutagenic or cancerogenic compounds, like chloroalkyl- and arylphosphates, and chloropropyl ethers originate from distinct sources as well. (orig.)

  2. Crystal Structure and Spectroscopic Properties of the Donor-acceptor Complex of 2-Amino-1,3-benzo- thiazole with Ethyl-5,6-benzocoumarin-3-carboxylate

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The donor-acceptor complex derived from 2-amino-1,3-benzothiazole (ABT) and ethyl 5,6-benzocoumarin-3-carboxylate (EBCC) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c, with a = 8.6485(3), b = 7.7743(3), c = 29.1963(10) (A), β = 92.0460(10)°, Z = 4, Mr = 418.45, V = 1961.79(12)(A)3, Dc = 1.417 g/cm3, μ = 0.199 mm-1, F(000) = 872, the final R = 0.0350 and wR = 0.1226. The complex is an A…D…D'…A' H-bonded tetramer. The intermolecular N-H…O and N-H…N hydrogen bonds, together with π-π stacking interactions, stabilize the crystal structure by forming a supramolecular architecture. It is found that, in solid state, the fluorescence emission of the complex is quenched significantly while the UV-vis spectrum exhibits a broad band at 346 nm with shoulder, which can be attributed to the donor-acceptor complex formed.

  3. Occurrence and fate of relevant substances in wastewater treatment plants regarding Water Framework Directive and future legislations.

    Science.gov (United States)

    Martin Ruel, S; Choubert, J-M; Budzinski, H; Miège, C; Esperanza, M; Coquery, M

    2012-01-01

    The next challenge of wastewater treatment is to reliably remove micropollutants at the microgram per litre range. During the present work more than 100 substances were analysed through on-site mass balances over 19 municipal wastewater treatment lines. The most relevant substances according to their occurrence in raw wastewater, in treated wastewater and in sludge were identified, and their fate in wastewater treatment processes was assessed. About half of priority substances of WFD were found at concentrations higher than 0.1 μg/L in wastewater. For 26 substances, potential non-compliance with Environmental Quality Standard of Water Framework Directive has been identified in treated wastewater, depending on river flow. Main concerns are for Cd, DEHP, diuron, alkylphenols, and chloroform. Emerging substances of particular concern are by-products, organic chemicals (e.g. triclosan, benzothiazole) and pharmaceuticals (e.g. ketoprofen, diclofenac, sulfamethoxazole, carbamazepine). About 80% of the load of micropollutants was removed by conventional activated sludge plants, but about two-thirds of removed substances were mainly transferred to sludge. PMID:22437014

  4. Mechanistic pathway for controlled extraction of guest molecule bound to herring sperm DNA using α-cyclodextrin

    Science.gov (United States)

    Jaffer, S. Syed; Ghosh, Prasun; Purkayastha, Pradipta

    2011-05-01

    trans-2-[4-(Dimethylamino)styryl]benzothiazole (DMASBT) is known to have dual emitting states where the locally excited (LE) state is responsible for fluorescence in less polar environment and in polar milieu fluorescence is from the twisted intramolecular charge transfer (TICT) state. This compound also undergoes minor groove binding to herring sperm DNA (hsDNA) evidenced by the absorption spectra before and after the binding process and an effect on DMASBT fluorescence by an anionic quencher. The binding occurs efficiently in a 1:1 manner, i.e. one guest molecule binds to one site on the hsDNA. Instead of following the DNA twist, the aromatic part seems to project outward. Thus, the bound molecule can be successfully extracted out from the DNA in a controlled way by the hydrophobic cavity of α-cyclodextrin (α-CD). The extraction starts even with a low concentration of α-CD and increases as the concentration is increased. Absorption, steady-state and time resolved fluorescence spectroscopic methods have been employed to explore the mechanistic pathway of binding of DMASBT to hsDNA. The mechanistic approach toward controlled extraction of the guest molecules from hsDNA by α-CD is reported and is expected to serve a significant purpose in treatment of drug overdose.

  5. Water networks contribute to enthalpy/entropy compensation in protein-ligand binding.

    Science.gov (United States)

    Breiten, Benjamin; Lockett, Matthew R; Sherman, Woody; Fujita, Shuji; Al-Sayah, Mohammad; Lange, Heiko; Bowers, Carleen M; Heroux, Annie; Krilov, Goran; Whitesides, George M

    2013-10-16

    The mechanism (or mechanisms) of enthalpy-entropy (H/S) compensation in protein-ligand binding remains controversial, and there are still no predictive models (theoretical or experimental) in which hypotheses of ligand binding can be readily tested. Here we describe a particularly well-defined system of protein and ligands--human carbonic anhydrase (HCA) and a series of benzothiazole sulfonamide ligands with different patterns of fluorination--that we use to define enthalpy/entropy (H/S) compensation in this system thermodynamically and structurally. The binding affinities of these ligands (with the exception of one ligand, in which the deviation is understood) to HCA are, despite differences in fluorination pattern, indistinguishable; they nonetheless reflect significant and compensating changes in enthalpy and entropy of binding. Analysis reveals that differences in the structure and thermodynamic properties of the waters surrounding the bound ligands are an important contributor to the observed H/S compensation. These results support the hypothesis that the molecules of water filling the active site of a protein, and surrounding the ligand, are as important as the contact interactions between the protein and the ligand for biomolecular recognition, and in determining the thermodynamics of binding.

  6. NHC-manganese(i) complexes as carbene transfer agents.

    Science.gov (United States)

    Ruiz, Javier; Berros, Angela; Perandones, Bernabé F; Vivanco, Marilín

    2009-09-21

    Tautomerization of coordinated azoles to their corresponding N-heterocyclic carbenes (NHCs) has been carried out by reaction of complexes fac-[Mn(L)(CO)(3)(dppe)](+) (L = N-phenylimidazole) and fac-[Mn(L)(CO)(3)(bipy)](+) (L = N-methylbenzimidazole, benzoxazole, benzothiazole) with KO(t)Bu and subsequent protonation of the azolyl intermediates with NH(4)PF(6). Several NHC-manganese(i) complexes bearing an N-H residue of general formula fac-[Mn(NHC)(CO)(3)(dppe)](+) and fac-[Mn(NHC)(CO)(3)(bipy)](+) have been tested as carbene transfer agents to the gold fragments [Au(L)](+) (L = PPh(3), CNPh, CNXylyl), allowing isolation or spectroscopic detection of various Mn(i)/Au(i) heterometallic intermediates containing azolyl bridging ligands, which liberate the gold(i) carbene complexes [Au(NHC)(L)](+) by means of acid hydrolysis. By contrast, when using the silver(i) fragment [Ag(PPh(3))](+) as carbene acceptor no transmetallation process occurred but instead inverse tautomerization of the NHC to the corresponding imidazole ligand was observed.

  7. Determination of benzotriazole corrosion inhibitors from aqueous environmental samples by liquid chromatography-electrospray ionization-tandem mass spectrometry.

    Science.gov (United States)

    Weiss, Stefan; Reemtsma, Thorsten

    2005-11-15

    The first method for the determination of commonly used corrosion inhibitors in environmental water samples by liquid chromatography-electrospray ionization-tandem mass spectrometry is presented. Benzotriazole (BTri) and the two isomers of tolyltriazole (5- and 4-TTri) are separated in an isocratic run. By gradient elution, BTri, 4-TTri, 5-TTri, and xylyltriazole can be determined simultaneously with three benzothiazoles, but here TTri isomers coelute. The instrumental detection limit of 2 pg allows the determination of the three most important benzotriazoles from municipal wastewater and most surface waters by direct injection into the HPLC system without previous enrichment. When solid-phase extraction is employed with mean recovery rates of 95-113%, the limit of quantification for benzotriazoles range from 10 ng/L in groundwater to 25 ng/L in untreated wastewater. BTri and TTri were determined in municipal wastewater in microgram per liter concentrations. Elimination in wastewater treatment appears to be poor, and BTri and TTri can be followed through a water cycle from treated municipal wastewater through surface water to bank filtrate used for drinking water production. The TTri isomers show markedly different biodegradation behavior with 4-TTri being more stable. PMID:16285694

  8. Discovery of gramine derivatives that inhibit the early stage of EV71 replication in vitro.

    Science.gov (United States)

    Wei, Yanhong; Shi, Liqiao; Wang, Kaimei; Liu, Manli; Yang, Qingyu; Yang, Ziwen; Ke, Shaoyong

    2014-01-01

    Enterovirus 71 (EV71) is a notable causative agent of hand, foot, and mouth disease in children, which is associated with an increased incidence of severe neurological disease and death, yet there is no specific treatment or vaccine for EV71 infections. In this study, the antiviral activity of gramine and 21 gramine derivatives against EV71 was investigated in cell-based assays. Eighteen derivatives displayed some degree of inhibitory effects against EV71, in that they could effectively inhibit virus-induced cytopathic effects (CPEs), but the anti-EV71 activity of the lead compound gramine was not observed. Studies on the preliminary modes of action showed that these compounds functioned by targeting the early stage of the EV71 lifecycle after viral entry, rather than inactivating the virus directly, inhibiting virus adsorption or affecting viral release from the cells. Among these derivatives, one (compound 4s) containing pyridine and benzothiazole units showed the most potency against EV71. Further studies demonstrated that derivative 4s could profoundly inhibit viral RNA replication, protein synthesis, and virus-induced apoptosis in RD cells. These results indicate that derivative 4s might be a feasible therapeutic agent against EV71 infection and that these gramine derivatives may provide promising lead scaffolds for the further design and synthesis of potential antiviral agents.

  9. Easy and Rapid Detection of Mumps Virus by Live Fluorescent Visualization of Virus-Infected Cells.

    Science.gov (United States)

    Takahashi, Tadanobu; Agarikuchi, Takashi; Kurebayashi, Yuuki; Shibahara, Nona; Suzuki, Chihiro; Kishikawa, Akiko; Fukushima, Keijo; Takano, Maiko; Suzuki, Fumie; Wada, Hirohisa; Otsubo, Tadamune; Ikeda, Kiyoshi; Minami, Akira; Suzuki, Takashi

    2015-01-01

    Mumps viruses show diverse cytopathic effects (CPEs) of infected cells and viral plaque formation (no CPE or no plaque formation in some cases) depending on the viral strain, highlighting the difficulty in mumps laboratory studies. In our previous study, a new sialidase substrate, 2-(benzothiazol-2-yl)-4-bromophenyl 5-acetamido-3,5-dideoxy-α-D-glycero-D-galacto-2-nonulopyranosidonic acid (BTP3-Neu5Ac), was developed for visualization of sialidase activity. BTP3-Neu5Ac can easily and rapidly perform histochemical fluorescent visualization of influenza viruses and virus-infected cells without an antiviral antibody and cell fixation. In the present study, the potential utility of BTP3-Neu5Ac for rapid detection of mumps virus was demonstrated. BTP3-Neu5Ac could visualize dot-blotted mumps virus, virus-infected cells, and plaques (plaques should be called focuses due to staining of infected cells in this study), even if a CPE was not observed. Furthermore, virus cultivation was possible by direct pick-up from a fluorescent focus. In conventional methods, visible appearance of the CPE and focuses often requires more than 6 days after infection, but the new method with BTP3-Neu5Ac clearly visualized infected cells after 2 days and focuses after 4 days. The BTP3-Neu5Ac assay is a precise, easy, and rapid assay for confirmation and titration of mumps virus.

  10. Imaging of influenza virus sialidase activity in living cells.

    Science.gov (United States)

    Kurebayashi, Yuuki; Takahashi, Tadanobu; Otsubo, Tadamune; Ikeda, Kiyoshi; Takahashi, Shunsaku; Takano, Maiko; Agarikuchi, Takashi; Sato, Tsubasa; Matsuda, Yukino; Minami, Akira; Kanazawa, Hiroaki; Uchida, Yuko; Saito, Takehiko; Kawaoka, Yoshihiro; Yamada, Toshihiro; Kawamori, Fumihiko; Thomson, Robin; von Itzstein, Mark; Suzuki, Takashi

    2014-01-01

    Influenza virus is rich in variation and mutations. It would be very convenient for virus detection and isolation to histochemically detect viral infection regardless of variation and mutations. Here, we established a histochemical imaging assay for influenza virus sialidase activity in living cells by using a new fluorescent sialidase substrate, 2-(benzothiazol-2-yl)-4-bromophenyl 5-acetamido-3,5-dideoxy-α-D-glycero-D-galacto-2-nonulopyranosidonic acid (BTP3-Neu5Ac). The BTP3-Neu5Ac assay histochemically visualized influenza virus-infected cells regardless of viral hosts and subtypes. Influenza virus neuraminidase-expressed cells, viral focus formation, and virus-infected locations in mice lung tissues were easily, rapidly, and sensitively detected by the BTP3-Neu5Ac assay. Histochemical visualization with the BTP3-Neu5Ac assay is extremely useful for detection of influenza viruses without the need for fixation or a specific antibody. This novel assay should greatly improve the efficiency of detection, titration, and isolation of influenza viruses and might contribute to research on viral sialidase.

  11. Easy and Rapid Detection of Mumps Virus by Live Fluorescent Visualization of Virus-Infected Cells.

    Directory of Open Access Journals (Sweden)

    Tadanobu Takahashi

    Full Text Available Mumps viruses show diverse cytopathic effects (CPEs of infected cells and viral plaque formation (no CPE or no plaque formation in some cases depending on the viral strain, highlighting the difficulty in mumps laboratory studies. In our previous study, a new sialidase substrate, 2-(benzothiazol-2-yl-4-bromophenyl 5-acetamido-3,5-dideoxy-α-D-glycero-D-galacto-2-nonulopyranosidonic acid (BTP3-Neu5Ac, was developed for visualization of sialidase activity. BTP3-Neu5Ac can easily and rapidly perform histochemical fluorescent visualization of influenza viruses and virus-infected cells without an antiviral antibody and cell fixation. In the present study, the potential utility of BTP3-Neu5Ac for rapid detection of mumps virus was demonstrated. BTP3-Neu5Ac could visualize dot-blotted mumps virus, virus-infected cells, and plaques (plaques should be called focuses due to staining of infected cells in this study, even if a CPE was not observed. Furthermore, virus cultivation was possible by direct pick-up from a fluorescent focus. In conventional methods, visible appearance of the CPE and focuses often requires more than 6 days after infection, but the new method with BTP3-Neu5Ac clearly visualized infected cells after 2 days and focuses after 4 days. The BTP3-Neu5Ac assay is a precise, easy, and rapid assay for confirmation and titration of mumps virus.

  12. Copper-mediated C-H activation/C-S cross-coupling of heterocycles with thiols

    KAUST Repository

    Ranjit, Sadananda

    2011-11-04

    We report the synthesis of a series of aryl- or alkyl-substituted 2-mercaptobenzothiazoles by direct thiolation of benzothiazoles with aryl or alkyl thiols via copper-mediated aerobic C-H bond activation in the presence of stoichiometric CuI, 2,2′-bipyridine and Na 2CO 3. We also show that the approach can be extended to thiazole, benzimidazole, and indole substrates. In addition, we present detailed mechanistic investigations on the Cu(I)-mediated direct thiolation reactions. Both computational studies and experimental results reveal that the copper-thiolate complex [(L)Cu(SR)] (L: nitrogen-based bidentate ligand such as 2,2′-bipyridine; R: aryl or alkyl group) is the first reactive intermediate responsible for the observed organic transformation. Furthermore, our computational studies suggest a stepwise reaction mechanism based on a hydrogen atom abstraction pathway, which is more energetically feasible than many other possible pathways including β-hydride elimination, single electron transfer, hydrogen atom transfer, oxidative addition/reductive elimination, and σ-bond metathesis. © 2011 American Chemical Society.

  13. About the cure kinetics in natural rubber/styrene Butadiene rubber blends at 433 K

    Energy Technology Data Exchange (ETDEWEB)

    Mansilla, M.A., E-mail: mmansilla@df.uba.ar [Laboratorio de Polimeros y Materiales Compuestos, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon 1, C1428EGA Buenos Aires (Argentina); Marzocca, A.J. [Laboratorio de Polimeros y Materiales Compuestos, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon 1, C1428EGA Buenos Aires (Argentina)

    2012-08-15

    Vulcanized blends of elastomers are employed in several goods mainly to improve physical properties and reduce costs. One of the most used blends of this kind is that composed by natural rubber (NR) and styrene butadiene rubber (SBR). The cure kinetic of these blends depends mainly on the compound formulation and the cure temperature and time. The preparation method of the blends can influence the mechanical properties of the vulcanized compounds. In this work the cure kinetic at 433 K of NR/SBR blends vulcanized with the system sulfur/TBBS (N-t-butyl-2-benzothiazole sulfenamide) is analyzed in samples prepared by mechanical mixing and solution blending. The two methods produce elastomer domains of NR and SBR, which present different microstructure due to the cure level attained during vulcanization. The cure kinetics is studied by means of rheometer tests and the model proposed by Kamal and Sourour. The analysis of the cure rate is presented and is related to the structure obtained during the vulcanization process.

  14. Identification of dengue viral RNA-dependent RNA polymerase inhibitor using computational fragment-based approaches and molecular dynamics study.

    Science.gov (United States)

    Anusuya, Shanmugam; Velmurugan, Devadasan; Gromiha, M Michael

    2016-07-01

    Dengue is a major public health concern in tropical and subtropical countries of the world. There are no specific drugs available to treat dengue. Even though several candidates targeted both viral and host proteins to overcome dengue infection, they have not yet entered into the later stages of clinical trials. In order to design a drug for dengue fever, newly emerged fragment-based drug designing technique was applied. RNA-dependent RNA polymerase, which is essential for dengue viral replication is chosen as a drug target for dengue drug discovery. A cascade of methods, fragment screening, fragment growing, and fragment linking revealed the compound [2-(4-carbamoylpiperidin-1-yl)-2-oxoethyl]8-(1,3-benzothiazol-2-yl)naphthalene-1-carboxylate as a potent dengue viral polymerase inhibitor. Both strain energy and binding free energy calculations predicted that this could be a better inhibitor than the existing ones. Molecular dynamics simulation studies showed that the dengue polymerase-lead complex is stable and their interactions are consistent throughout the simulation. The hydrogen-bonded interactions formed by the residues Arg792, Thr794, Ser796, and Asn405 are the primary contributors for the stability and the rigidity of the polymerase-lead complex. This might keep the polymerase in closed conformation and thus inhibits viral replication. Hence, this might be a promising lead molecule for dengue drug designing. Further optimization of this lead molecule would result in a potent drug for dengue. PMID:26262439

  15. Ho{sup 3+} carbon paste sensor based on multi-walled carbon nanotubes: Applied for determination of holmium content in biological and environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Faridbod, Farnoush [Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Endocrinology and Metabolism Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Ganjali, Mohammad Reza, E-mail: ganjali@khayam.ut.ac.ir [Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Endocrinology and Metabolism Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Larijani, Bagher [Endocrinology and Metabolism Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Hosseini, Morteza [Department of Chemistry, Islamic Azad University, Savadkooh Branch, Savadkooh (Iran, Islamic Republic of); Norouzi, Parviz [Endocrinology and Metabolism Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran (Iran, Islamic Republic of)

    2010-05-10

    For the first time a novel multi-walled carbon nanotubes (MWCNTs) modified Ho{sup 3+} carbon paste sensor is introduced. The electrode with a composition containing 20% paraffin oil, 60% graphite powder, 15% N-(1-thia-2-ylmethylene)-1,3-benzothiazole-2-amine (TBA) as an ionophore, and 5% MWCNTs, exhibits a stable potential response to Ho{sup 3+} ions with a nice Nernstian behavior (19.3 {+-} 0.3 mV decade{sup -1}) in a wide dynamic linear concentration range of Ho{sup 3+} ions (1 x 10{sup -8}-1.0 x 10{sup -2} M). In the absence of MWCNTs, sensitivity of the Ho{sup 3+} sensor was relatively poor. The proposed modified Ho{sup 3+} sensor shows very low detection limit (7.0 x 10{sup -9} M) and a fast response time (13 s). It has a long life time (more than 2 months) and its response is independent of pH in the range of 3.8-7.5. In term of selectivity, Ho{sup 3+} sensor has a good selectivity over all lanthanide members and common alkali and alkaline earth metal ions. The Ho{sup 3+} sensor was applied for the determination of Ho{sup 3+} ion concentration in water, holmium alloys and synthetic human serum.

  16. Modeling the nonradiative decay rate of electronically excited thioflavin T.

    Science.gov (United States)

    Erez, Yuval; Liu, Yu-Hui; Amdursky, Nadav; Huppert, Dan

    2011-08-01

    A computational model of nonradiative decay is developed and applied to explain the time-dependent emission spectrum of thioflavin T (ThT). The computational model is based on a previous model developed by Glasbeek and co-workers (van der Meer, M. J.; Zhang, H.; Glasbeek, M. J. Chem. Phys. 2000, 112, 2878) for auramine O, a molecule that, like ThT, exhibits a high nonradiative rate. The nonradiative rates of both auramine O and ThT are inversely proportional to the solvent viscosity. The Glasbeek model assumes that the excited state consists of an adiabatic potential surface constructed by adiabatic coupling of emissive and dark states. For ThT, the twist angle between the benzothiazole and the aniline is responsible for the extensive mixing of the two excited states. At a twist angle of 90°, the S(1) state assumes a charge-transfer-state character with very small oscillator strength, which causes the emission intensity to be very small as well. In the ground state, the twist angle of ThT is rather small. The photoexcitation leads first to a strongly emissive state (small twist angle). As time progresses, the twist angle increases and the oscillator strength decreases. The fit of the experimental results by the model calculations is good for times longer than 3 ps. When a two-coordinate model is invoked or a solvation spectral-shift component is added, the fit to the experimental results is good at all times. PMID:21711024

  17. 2-Benzazolyl-4-Piperazin-1-Ylsulfonylbenzenecarbohydroxamic Acids as Novel Selective Histone Deacetylase-6 Inhibitors with Antiproliferative Activity.

    Directory of Open Access Journals (Sweden)

    Lei Wang

    Full Text Available We have screened our compound collection in an established cell based assay that measures the derepression of an epigenetically silenced transgene, the locus derepression assay. The screen led to the identification of 4-[4-(1-methylbenzimidazol-2-ylpiperazin-1-yl]sulfonylbenzenecarbohydroxamic acid (9b as an active which was found to inhibit HDAC1. In initial structure activity relationships study, the 1-methylbenzimidazole ring was replaced by the isosteric heterocycles benzimidazole, benzoxazole, and benzothiazole and the position of the hydroxamic acid substituent on the phenyl ring was varied. Whereas compounds bearing a para substituted hydroxamic acid (9a-d were active HDAC inhibitors, the meta substituted analogues (8a-d were appreciably inactive. Compounds 9a-d selectively inhibited HDAC6 (IC50 = 0.1-1.0 μM over HDAC1 (IC50 = 0.9-6 μM and moreover, also selectively inhibited the growth of lung cancer cells vs. patient matched normal cells. The compounds induce a cell cycle arrest in the S-phase while induction of apoptosis is neglible as compared to controls. Molecular modeling studies uncovered that the MM-GBSA energy for interaction of 9a-d with HDAC6 was higher than for HDAC1 providing structural rationale for the HDAC6 selectivity.

  18. 3-D QSAR CoMFA study of nitrogen mustards possessing new chemical entities as possible anticancer agents

    Directory of Open Access Journals (Sweden)

    Anand R

    2006-01-01

    Full Text Available This present work is an investigation of anticancer activities of the nitrogen mustards possessing quinazolinone, benzimidazole, benzoxazole, and benzothiazole nuclei by the three-dimensional Quantitative Structure Activity paradigm, Comparative Molecular Field Analysis. A total of 39 compounds were modelled in SYBYL 6.7 (Tripos, USA. The molecules were aligned by root-mean-square fit of atoms and field fit of the steric and electrostatic molecular fields and the resulting databases analysed by partial least squares analysis with cross-validation, leave-one-out and no validation to extract the optimum number of components. The analysis was then repeated with bootstrapping to give the final Quantitative Structure Activity Relationship models. Eight compounds, which were kept separately as test set, were used to test the predictive ability of the Comparative Molecular Field Analysis models. Out of the two models generated, one was found to be useful. The predicted activities of the test set were in good agreement with experimentally determined values.

  19. 2-Benzazolyl-4-Piperazin-1-Ylsulfonylbenzenecarbohydroxamic Acids as Novel Selective Histone Deacetylase-6 Inhibitors with Antiproliferative Activity

    Science.gov (United States)

    Wang, Lei; Kofler, Marina; Brosch, Gerald; Melesina, Jelena; Sippl, Wolfgang; Martinez, Elisabeth D.; Easmon, Johnny

    2015-01-01

    We have screened our compound collection in an established cell based assay that measures the derepression of an epigenetically silenced transgene, the locus derepression assay. The screen led to the identification of 4-[4-(1-methylbenzimidazol-2-yl)piperazin-1-yl]sulfonylbenzenecarbohydroxamic acid (9b) as an active which was found to inhibit HDAC1. In initial structure activity relationships study, the 1-methylbenzimidazole ring was replaced by the isosteric heterocycles benzimidazole, benzoxazole, and benzothiazole and the position of the hydroxamic acid substituent on the phenyl ring was varied. Whereas compounds bearing a para substituted hydroxamic acid (9a-d) were active HDAC inhibitors, the meta substituted analogues (8a-d) were appreciably inactive. Compounds 9a-d selectively inhibited HDAC6 (IC50 = 0.1–1.0μM) over HDAC1 (IC50 = 0.9–6μM) and moreover, also selectively inhibited the growth of lung cancer cells vs. patient matched normal cells. The compounds induce a cell cycle arrest in the S-phase while induction of apoptosis is neglible as compared to controls. Molecular modeling studies uncovered that the MM-GBSA energy for interaction of 9a-d with HDAC6 was higher than for HDAC1 providing structural rationale for the HDAC6 selectivity. PMID:26698121

  20. Synthesis of Some New Heterocycles Derived from Phenylacetyl Isothiocyanate

    Institute of Scientific and Technical Information of China (English)

    HEMDAN M.M.; FAHMY A.F.; ALI N.F.; HEGAZI E.; ABD-ELHALEEM A.

    2008-01-01

    Phenylacetyl isothiocyanate (1) was reacted with benzoyl hydrazine (2a) in acetonitrile to give thiosemicarbazide derivative 3 which was cyclized by polyphosphoric acid to give 1,2,4-triazoline-5-thione derivative 4.Treatment of 1 with thiosemicarbazide (2b) yielded another 1,2,4-triazoline-5-thione derivative 5.Similar treatment of 1 with phenyl hydrazine (2c) in acetonitrile gave a differently substituted 1,2,4-triazoline-5-thione derivative 6 in one pot-reaction.On the other hand, when the reaction was carried out in acetone, a mixture of 6 and thiadiazolidine derivative 7 was obtained.However, reaction of 1 with hydrazine hydrate (2d) gave hydrazine derivative 8.Reaction of isothiocyanate 1 with anthranilic acid (9) gave benzo[d][1,3,6]oxazin-1-one derivative 10.Treatment of 1 with 2-aminothiophenol (11a), 2-aminophenol (11b) or o-phenylenediamine (11c) produced benzothiazole derivative 12a, benzoxazole derivative 12b and benzimidazole derivative 12c, respectively.The structures of all the products were confirmed by micro-analytical and spectral data.

  1. Redox effects and cytotoxic profiles of MJ25 and auranofin towards malignant melanoma cells

    Science.gov (United States)

    Drummond, Catherine J.; McCarthy, Anna R.; Higgins, Maureen; Campbell, Johanna; Brodin, Bertha; Arnér, Elias S.J.; Laín, Sonia

    2015-01-01

    Malignant melanoma is the most dangerous type of skin cancer. Although recent progress in treatment has been achieved, lack of response, drug resistance and relapse remain major problems. The tumor suppressor p53 is rarely mutated in melanoma, yet it is inactive in the majority of cases due to dysregulation of upstream pathways. Thus, we screened for compounds that can activate p53 in melanoma cells. Here we describe effects of the small molecule MJ25 (2-{[2-(1,3-benzothiazol-2-ylsulfonyl)ethyl]thio}-1,3-benzoxazole), which increased the level of p53-dependent transactivation both as a single agent and in combination with nutlin-3. Furthermore, MJ25 showed potent cytotoxicity towards melanoma cell lines, whilst having weaker effects against human normal cells. MJ25 was also identified in an independent screen as an inhibitor of thioredoxin reductase 1 (TrxR1), an important selenoenzyme in the control of oxidative stress and redox regulation. The well-characterized TrxR inhibitor auranofin, which is FDA-approved and currently in clinical trials against leukemia and a number of solid cancers, displayed effects comparable with MJ25 on cells and led to eradication of cultured melanoma cells at low micromolar concentrations. In conclusion, auranofin, MJ25 or other inhibitors of TrxR1 should be evaluated as candidate compounds or leads for targeted therapy of malignant melanoma. PMID:26029997

  2. Monophthalocyanine complexes of samarium and terbium with axial ligands:synthesis, structure and optoelectronic properties

    Institute of Scientific and Technical Information of China (English)

    Alexander A Maleev; Mikhail N Bochkarev; Anatoly P Pushkarev; Vasily A Ilichev; Mikhail A Lopatin; Maxim A Samsonov; Georgy K Fukin; Georgy L Pakhomov; Vladislav V Travkin; Ivan D Grishin

    2014-01-01

    The monophthalocyanine complexes of samarium and terbium containing axial 2-mercaptobenzothiazole (PcSm(MBT) (1)), 2-(2-benzoxazol-2-yl) phenolate (PcTb(OON) (2)) or 2-(2-benzothiazol-2-yl)phenolate (PcTb(SON) (3)) ligands were synthe-sized and identified by elemental, LDI-TOF and X-ray (for 1) analysis. Photoluminescence (PL) and electroluminescence (EL) spec-tra of the compounds contained only emission bands of phthalocyanine and axial ligands but did not contain the bands of f-f transi-tions. It was found that among the complexes 1, 2, 3 the latter had highest photoconductivity (~10–7 S/cm) and photovoltaic properties. An organic photovoltaic device (OPV) of configuration of ITO/3/C60/Alq3/Al revealed open-circuit voltage (VOC) of 0.24 V and short current density (ISC) of 0.3μA/cm2 under illumination by a xenon lamp at 17 mW/cm2.

  3. Experiments regarding the development of sulfur-containing chelating agents for excretion via the biliary duct as an antidote therapy of cadmium intoxication. Versuche zur Entwicklung schwefelhaltiger, biliaer eliminierbarer Chelatbildner zur Antidottherapie bei Cadmium-Intoxikationen

    Energy Technology Data Exchange (ETDEWEB)

    Dierks, T.

    1988-01-01

    The study represents an effort to synthesize new cadmium complexing agents which would be free of the shortcomings of substances available so far. As the kidneys seem to be the 'critical organs' both in cadmium intoxication and in chelate therapy, the new compounds were to assure elimination of the cadmium chelate formed via the biliary tract. After introductory chapters, the work first of all describes the syntheses of the new potential complexing agents. The second part of the work attempts to transform known chelating agents into substances permitting biliary excretion by forming derivatives with a diazomethane containing cumarin as a substitute. However, no suitable chelate compound could be obtained. The last part studies the cadmium complexing capability of the synthesized 3,6-dioxaoctanedithioamides 4 and 8 and of the N-(1,3-benzothiazol-2-yl)-thioacetamide 6 using different methods. Only the compound N,N,N',N'-tetrabutyl-3,6-dioxaoctanedithioamide 4/sup 104-106/, previously described in literature, and the monothioamide 6 formed cadmium chelates. But these compounds, having a relatively low molecular weight, are unlikely to satisfy the requirements for elimination via the biliary duct.

  4. Synthesis, characterization and studies on antioxidant and molecular docking of metal complexes of 1-(benzo[d]thiazol-2-yl)thiourea

    Indian Academy of Sciences (India)

    Harinath Yapati; Subba Rao Devineni; Suresh Chirumamilla; Seshaiah Kalluru

    2016-01-01

    In the present study, a new thiourea derivative bearing benzothiazole ligand, 1-(benzo[d]thiazol-2-yl)thiourea (btt) and its ternary metal (Cu(II), Co(II) and Ni(II)) complexes were synthesized. The structural characterization was carried out by micro analysis, IR, 1H-NMR, EPR, UV-Visible spectral analyses, molar conductance and thermal analysis studies. Spectral studies of complexes revealed that the metal complexes have distorted octahedral geometry. Molecular modelling study was performed to evaluate the recognition of target compounds at the 3MNG binding pocket. The docking results revealed that copper complex selectively binds to the crucial amino acid residues in the active site of 3MNG. The in vitro antioxidant activity of the ligand and its metal complexes was assayed by radical scavenging activity (DPPH, H2O2 and NO) and ferric reducing antioxidant power (FRAP) methods. The ligand showed moderate antioxidant activity whereas the metal complexes exhibited better antioxidant activity than that of the ligand. The results of the four methods proved that the copper complex is the most potent antioxidant among all the tested compounds.

  5. In vitro anticancer activities of Schiff base and its lanthanum complex

    Science.gov (United States)

    Neelima; Poonia, Kavita; Siddiqui, Sahabjada; Arshad, Md; Kumar, Dinesh

    2016-02-01

    Schiff base metal complexes are well-known to intercalate DNA. The La(III) complexes have been synthesized such that they hinder with the role of the topoisomerases, which control the topology of DNA during the cell-division cycle. Although several promising chemotherapeutics have been developed, on the basis of Schiff base metal complex DNA intercalating system they did not proceed past clinical trials due to their dose-limiting toxicity. Herein, we discuss an alternative compound, the La(III) complex, [La(L1)2Cl3]·7H2O based on a Schiff base ligand 2,3-dihydro-1H-indolo-[2,3-b]-phenazin-4(5H)-ylidene)benzothiazole-2-amine (L1), and report in vitro cell studies. Results of antitumor activity using cell viability assay, reactive oxygen species (ROS) generation and nuclear condensation in PC-3 (Human, prostate carcinoma) cells show that the metal complex is more potent than ligand. La(III) complexes have been synthesized by reaction of lanthanum(III) salt in 1:2 M ratio with ligands L1 and 3-(ethoxymethylene)-2,3-dihydro-1H-indolo[2,3-b]-phenazin-4(5H)-ylidene)benzathiazole-2-amine (L2) in methanol. The ligands and their La(III) complexes were characterized by molar conductance, magnetic susceptibility, elemental analyses, FT-IR, UV-Vis, 1H/13C NMR, thermogravimetric, XRD, and SEM analysis.

  6. Gamma irradiation of 2-mercaptobenzothiazole aqueous solution in the presence of persulfate.

    Science.gov (United States)

    Bao, Qiburi; Chen, Lujun; Tian, Jinping; Wang, Jianlong

    2016-08-01

    Recently, water treatment by ionizing radiation has gained increasing attention as a powerful technology for the destruction of refractory pollutants. 2-Mercaptobenzothiazole (MBT) is known as a widespread, toxic and poorly biodegradable pollutant. This paper studied the gamma irradiation of aqueous solutions of MBT. Moreover, the effect of the addition of persulfate (S2O8(2-)) on the radiolytic destruction of MBT was investigated. The main transformation products of the studied compound were detected and the sequence of occurrence of the products was described. The change of biodegradability of MBT solution was also observed. The main results obtained in this study indicated that gamma radiation was effective for removing MBT in aqueous solution. Persulfate addition, which induced the formation of reactive sulfate radicals (SO4(-)), greatly enhanced the degradation of MBT. Benzothiazole was identified as the first radiation product, followed by 2-hydroxybenzothiazole. Decomposition of MBT started with the oxidation of -SH groups to sulfate ions. Possible pathways for MBT decomposition by gamma irradiation were proposed. The BOD/COD ratios of MBT samples were increased after radiation, indicating the improvement of biodegradability and reduction of toxicity. PMID:27521957

  7. An investigation on the inhibitory action of benzazole derivatives as a consequence of sulfur atom induction

    Science.gov (United States)

    Moradi, Z.; Attar, M. M.

    2014-10-01

    The inhibitory action of three benzazole based molecules namely 2-methyl benzimidazole (2-MBI), 2-methyl benzothiazole (2-MBT) and 2-mercapto benzthiazole (2-SHBT) in 1 M HCl solution was studied by gravimetric analysis and electrochemical impedance spectroscopy (EIS). Results showed that the inhibitor adsorption on the iron surface was according to Langmuir adsorption isotherm for 2-MBI and 2-MBT and Flory Huggins Isotherm for 2-SHBT. Surface roughness obtained by Atomic Forced Microscopy (AFM) revealed that a good inhibitor decreases the surface roughness significantly which can be related to the formation of more integrated molecular film of inhibitor on steel surface. Based on contact angle (CA) measurements as the efficiency of the inhibitor molecules improve the hydrophobicity increases. These three molecules were chosen to see the effect of introducing sulfur atom into the structure the main effect of which would be on electronic parameters. To better understand this effect, the quantum chemical descriptors including: EHOMO, ELUMO, energy gap (ΔE), dipole moment (μ), hardness (η), softness (σ), electronegativity index (χ), fraction of electrons transferred (ΔN), that are most relevant to the potential action of a molecule as corrosion inhibitor, have been calculated in water and vacuum. Electronic parameters of these three inhibitors have been studied using DFT/B3LYP, and HF methods with 6-31G (d,p) basis set.

  8. Ho3+ carbon paste sensor based on multi-walled carbon nanotubes: Applied for determination of holmium content in biological and environmental samples

    International Nuclear Information System (INIS)

    For the first time a novel multi-walled carbon nanotubes (MWCNTs) modified Ho3+ carbon paste sensor is introduced. The electrode with a composition containing 20% paraffin oil, 60% graphite powder, 15% N-(1-thia-2-ylmethylene)-1,3-benzothiazole-2-amine (TBA) as an ionophore, and 5% MWCNTs, exhibits a stable potential response to Ho3+ ions with a nice Nernstian behavior (19.3 ± 0.3 mV decade-1) in a wide dynamic linear concentration range of Ho3+ ions (1 x 10-8-1.0 x 10-2 M). In the absence of MWCNTs, sensitivity of the Ho3+ sensor was relatively poor. The proposed modified Ho3+ sensor shows very low detection limit (7.0 x 10-9 M) and a fast response time (13 s). It has a long life time (more than 2 months) and its response is independent of pH in the range of 3.8-7.5. In term of selectivity, Ho3+ sensor has a good selectivity over all lanthanide members and common alkali and alkaline earth metal ions. The Ho3+ sensor was applied for the determination of Ho3+ ion concentration in water, holmium alloys and synthetic human serum.

  9. SYNTHESIS, CHARACTERIZATION AND RING-OPENING POLYMERIZATION OF CYCLIC (ARYLENE PHOSPHONATE) OLIGOMERS

    Institute of Scientific and Technical Information of China (English)

    Hong-ming Zhang; Qing-zhong Guo; Tian-lu Chen

    2004-01-01

    A series of cyclic (arylene phosphonate) oligomers were prepared by reaction of phenylphosphonic dichloride (PPD) with various bisphenols under pseudo-high dilution conditions via interfacial polycondensation. The yield of cyclic (arylenc phosphonate) oligomers is over 85% by using hexadecyltrimethylammonium bromide as phase transfer catalyst (PTC) at 0 ℃. The structures of the cyclic oligomers were confirmed by a combination of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and IR analysis. These cyclic oligomers undergo facile ring-opening polymerization in the melt by using potassium 4,4'-biphenoxide as the initiator to give linear polyphosphonate. Free-radical ring-opening polymerization of cyclic(arylene phosphonate) oligomers containing sulfur linkages was also performed in the melt using 2,2'-dithiobis(benzothiazole) (DTB) as the initiator at 270℃ and the resulting polymer had a Mw of 8 × 103 with a molecular weight distribution of 4. Ring-opening copolymerization of these cyclic oligomers with cyclic carbonate oligomers was also achieved. The average molecular weight of the resulting copolymer is higher than the corresponding homopolymer and the thermal stability of the copolymer is better than the corresponding homopolymer.

  10. 离子传感器材料Ir(ppy)2(O^N)配合物的结构和光谱特征%The Structures and Spectroscopic Properties of Ion Transducer Material Ir(ppy) 2 (O^N) Complexes

    Institute of Scientific and Technical Information of China (English)

    张建坡; 金丽; 李岩; 郝希云

    2014-01-01

    采用密度泛函方法对两种Ir(ppy)2(O^N)(ppy=2-苯基吡啶;O^N=2-(2-羟基苯)-苯并噻唑(1), O^N=2-(2-羟基苯)-苯并恶唑(2))配合物的几何结构和光谱特征进行了详细的理论研究。计算得到的Ir-N(1)、 Ir-N(3)和Ir-O(1)基态键长和相应实验值符合得较好。激发态下, Ir-N(1)和Ir-C(1)键长均增加了约0.02~0.05Å,而Ir-O(1)键长则缩短了大约0.02Å。在TD-DFT计算水平下结合极化连续介质( PCM)模型,得到1~2的最低能吸收和发射分别出现在484 nm(1)、441 nm (2)和624 nm(1)、519 nm(2)。1和2的此跃迁均属于[d(Ir)+π(ppy)+π(O^N)→π*(O^N)]的电荷转移跃迁。计算结果表明, ppy和O^N配体在跃迁过程中担当两个独立的发色团。与分子2相比,由于1在O^N配体上存在噻唑环,导致其分子整体结构变化较大,并使吸收和发射波长产生明显红移。%The geometries and spectroscopic properties of a series of Ir (ppy)2(O^N)(ppy=2-phenylpyridine;O^N=2-(2-Hydroxyphenyl) -benzothiazole (1), O^N =2 -(2 -hydroxyphenyl) -benzoxazole (2)) were investigated theoretically.The calculated bond lengths of Ir-N(1), Ir-N(3) and Ir-O(1) in the ground state agreed well with the corresponding experimental results.Upon excitation, the bond lengths of Ir -N(1) and Ir-C(1) lengthen by 0.02~0.05 Åand that of Ir-O(1) shortened by 0.02Å.At the TD-DFT level with the PCM model , 1~2 give rise to lowest -lying absorptions at 484(1), 441(2) nm and phosphorescent emissions at 624(1), 519(2) nm, respectively.The transitions of 1, 2 were attributed to [d(Ir)+π(ppy)+π(O^N)→π*(O^N)] charge transfer.The calculated results showed that the ppy and O^N groups acted as two independent chromospheres in transition processes.Compared with 2 , the geometric structure was greatly affected and the absorptions and emissions were red -shifted by

  11. Principal component analysis with pre-normalization improves the signal-to-noise ratio and image quality in positron emission tomography studies of amyloid deposits in Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Razifar, Pasha [Molecular Imaging and CT Research, GE Healthcare, WI 53188, Waukesha (United States); Engler, Henry [Department of Medical Science, Uppsala University, SE-751 85 Uppsala (Sweden); Blomquist, Gunnar [Department of Oncology, Radiology and Clinical Immunology, Uppsala University, SE-751 85 Uppsala (Sweden); Ringheim, Anna; Estrada, Sergio [Uppsala Imanet AB, GE Healthcare, Box 967, SE-751 09, Uppsala (Sweden); Laangstroem, Bengt [Department of Biochemistry and Organic Chemistry, Uppsala University, SE-751 24 Uppsala (Sweden); Bergstroem, Mats [Department of Pharmaceutical Biosciences, Uppsala University, SE-751 24 Uppsala (Sweden)

    2009-06-07

    This study introduces a new approach for the application of principal component analysis (PCA) with pre-normalization on dynamic positron emission tomography (PET) images. These images are generated using the amyloid imaging agent N-methyl [{sup 11}C]2-(4'-methylaminophenyl)-6-hydroxy-benzothiazole ([{sup 11}C]PIB) in patients with Alzheimer's disease (AD) and healthy volunteers (HVs). The aim was to introduce a method which, by using the whole dataset and without assuming a specific kinetic model, could generate images with improved signal-to-noise and detect, extract and illustrate changes in kinetic behavior between different regions in the brain. Eight AD patients and eight HVs from a previously published study with [{sup 11}C]PIB were used. The approach includes enhancement of brain regions where the kinetics of the radiotracer are different from what is seen in the reference region, pre-normalization for differences in noise levels and removal of negative values. This is followed by slice-wise application of PCA (SW-PCA) on the dynamic PET images. Results obtained using the new approach were compared with results obtained using reference Patlak and summed images. The new approach generated images with good quality in which cortical brain regions in AD patients showed high uptake, compared to cerebellum and white matter. Cortical structures in HVs showed low uptake as expected and in good agreement with data generated using kinetic modeling. The introduced approach generated images with enhanced contrast and improved signal-to-noise ratio (SNR) and discrimination power (DP) compared to summed images and parametric images. This method is expected to be an important clinical tool in the diagnosis and differential diagnosis of dementia.

  12. Application of pyridine-2-carbaldehyde-2-(4-methyl-1,3-benzo thiazol-2-yl)hydrazone as a neutral ionophore in the construction of a novel Er(III) sensor

    Energy Technology Data Exchange (ETDEWEB)

    Ganjali, Mohammad Reza; Norouzi, Parviz [University of Tehran, Tehran (Iran, Islamic Republic of). Center of Excellence in Electrochemistry; Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of). Endocrine and Metabolism Research Center; E-mail: ganjali@khayam.ut.ac.ir; Rezapour, Morteza; Rasoolipour, Solmaz [University of Tehran, Tehran (Iran, Islamic Republic of). Center of Excellence in Electrochemistry; Adib, Mehdi [University of Tehran, Tehran (Iran, Islamic Republic of). University College of Science. Faculty of Chemistry

    2007-03-15

    We found that pyridine-2-carbaldehyde-2-(4-methyl-1,3-benzothiazol-2-yl) hydrazone (PCMHT) can be used as a suitable neutral ionophore for preparing an Er(III) membrane sensor with high selectivity. The optimum composition was found to be PCMHT-PVC-KTpClPB-BA with the ratios of 6.0:30.0:5.0:59.0, respectively. The Nernstian response was of 21.8 {+-} 0.5 mV decade{sup -1} of Er(III) activity, the linear range of the sensor was found to be relatively wide (from 1.0X10{sup -5} to 1.0 X10{sup -2} mol L{sup -1}). Its applicability pH range of 2.5-12.0 seems to make it suitable for analytical applications. The lower detection limit (LDL) of the sensor was 5.0 X10{sup -6} mol L{sup -1}. The excellent Er(III)-selectivity of the proposed sensor with regard to most common metal ions, and especially, lanthanide ions is another advantage. It was successfully used as an indicator electrode for titration of 25 mL of a 1.0 X 10{sup -4} mol L{sup -1} Er(III) ions with a 1.0 X 10{sup -}2 mol L{sup -1} EDTA. The proposed sensor was used for direct monitoring of Er(III) in binary mixtures and indirect determination of fluoride ions in two mouth wash preparations. (author)

  13. Therapeutic effects of FuZhiSan on Alzheimer's disease rat model:evaluation with PET imaging

    International Nuclear Information System (INIS)

    Objective: To assess the feasibility of using PET molecular imaging to evaluate the therapeutic effects of traditional Chinese medicine FuZhiSan (FZS) on the model of aging Alzheimer's disease (AD) rats. Methods: Twenty aged AD rats (Sparague-Dawley rats,male) were randomly divided into FZS treated group (n = 10) and control group (n = 10). Another 10 healthy adult rats were as blank controls. Morris water maze record system was used for cognitive function assessment. Before and after FZS treatment 18F-fluorodeoxyglucose (FDG) and 11C-2- [4'-(methylamino) phenyl] benzothiazol-6-ol (PIB) PET imaging was undertaken. After post-treatment imaging procedures the brain tissues of all animals were taken for histochemical study, such as staining with HE, congo red, amyloid β (Aβ) immunofluorescence, 5-bromo-2-deoxyuridine (BrdU) immunofluorescence and NeuN immunofluorescence. Paired t-test was performed with SPSS 13.0 software for the data analysis. Results: The cognitive dysfunction of aging AD rats was improved after FZS treatment. The escape latency in FZS treated group was significantly shorter than that of control group ((32.5 ±10.8) s vs (102.6±8.8) s, t =15.7987, P=0. 0001). Diffuse neuronal loss and Aβ deposition were detected in the hippocampus and cortex in the aged AD rats. The imaging data showed that brain glucose metabolism was amended in FZS treated group while the abatement of amyloid deposition was not significant. Immunofluorescence results indicated that the neuronal proliferation was more remarkable in FZS treated group. Conclusions: It may be feasible to use PET imaging as a method to evaluate the therapeutic effect in AD rats. FZS may ameliorate memory dysfunction of aged AD rats. Its mechanism may be partly contributed to the enhancement of the neuronal proliferation and survival. (authors)

  14. The activities of polyphenol oxidase in Populus simonii×P. pyramidalis 'Opera 8277' leaves in response to insect herbivory and volatiles exposure%虫咬及挥发物诱导后合作杨叶片中多酚氧化酶活性的变化

    Institute of Scientific and Technical Information of China (English)

    胡增辉; 沈应柏; 王宁宁; 王金凤; 周艳超; 张志毅

    2009-01-01

    经杨扇舟蛾(Clostera anachoreta)幼虫取食,杨扇舟蛾幼虫诱导的挥发物熏蒸,及茉莉酸甲酯(MeJA)、水杨酸甲酯(MeSA)、顺式己烯醛(cis-hexenal)、反式己烯醛(trans-hexenal)及苯骈噻唑(benzothiazole)熏蒸后,分析了合作杨(Populus simonii×P. pyramidalis 'Opera 8277')叶片中多酚氧化酶(PPO)活性的变化.虫咬叶及其上部叶片中PPO活性增加了2~4倍,表明合作杨产生了系统抗性.经虫咬诱导的挥发物熏蒸后,合作杨叶片中的PPO活性增加了1倍,推测是合作杨受伤后释放出了具有信号作用的挥发物,诱导邻近植株产生了防御反应.5种外源挥发物都引起了叶片PPO活性升高,因此均可能是合作杨间潜在的气体信号,并且混合挥发物的诱导效果显著高于单一挥发物.EGTA(钙离子螯合剂)和氯化镧(钙通道抑制剂)明显抑制了合作杨虫咬叶片、虫咬上部叶片及虫咬诱导挥发物熏蒸叶中PPO活性的升高,说明钙信号在虫咬及挥发物诱导的PPO活性升高中起着重要作用.

  15. 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.

    Science.gov (United States)

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

    2014-06-01

    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

  16. Gadolinium Nanoparticles Conjugated with Therapeutic Bifunctional Chelate as a Potential T1 Theranostic Magnetic Resonance Imaging Agent.

    Science.gov (United States)

    Kang, Min-Kyoung; Lee, Gang Ho; Jung, Ki-Hye; Jung, Jae-Chang; Kim, Hee-Kyung; Kim, Yeon-Hee; Lee, Jongmin; Ryeom, Hun-Kyu; Kim, Tae-Jeong; Chang, Yongmin

    2016-05-01

    This work is directed toward the synthesis of two types of gadolinium oxide nanoparticles (Gd-oxide NPs), abbreviated as Gd@SiO2-DO3A and Gd@SiO2-DO2A-BTA, with diameters of 50-60 nm. The synthesis involves sequential coating of Gd-oxide NPs with tetraethyl orthosilicate (TEOS) and (3-aminopropyl) triethoxysilane (APTES), followed by functionalization of the aminopropylsilane group with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) or 1,4,7,10-tetraazacyclododecane-1,4,7-trisacetic acid conjugates of benzothiazoles (DO3A-BTA). Gd@SiO2-DO3A and Gd@SiO2-DO2A-BTA exhibit high water solubility and colloidal stability. The r1 relaxivities of both Gd@SiO2-DO3A and Gd@SiO2-DO2A-BTA are higher than those of the corresponding low-molecular-weight magnetic resonance imaging contrast agents (MRI CAs), and their r2/r1 ratios are close to 1, indicating that both can be used as potential T1 MRI CAs. Biodistribution studies demonstrated that Gd@SiO2-DO2A-BTA was excreted via both hepatobiliary and renal pathways. Gd@SiO2-DO2A-BTA exhibits a strong intracellular uptake property in a series of tumor cell lines, and has significant anticancer characteristics against cell lines such as SK-HEP-1, MDA-MB-231, HeLa, and Hep-3B.

  17. Combined thioflavin T–Congo red fluorescence assay for amyloid fibril detection

    Science.gov (United States)

    Girych, Mykhailo; Gorbenko, Galyna; Maliyov, Ivan; Trusova, Valeriya; Mizuguchi, Chiharu; Saito, Hiroyuki; Kinnunen, Paavo

    2016-09-01

    Fluorescence represents one of the most powerful tools for the detection and structural characterization of the pathogenic protein aggregates, amyloid fibrils. The traditional approaches to the identification and quantification of amyloid fibrils are based on monitoring the fluorescence changes of the benzothiazole dye thioflavin T (ThT) and absorbance changes of the azo dye Congo red (CR). In routine screening it is usually sufficient to perform only the ThT and CR assays, but both of them, when used separately, could give false results. Moreover, fibrillization kinetics can be measured only by ThT fluorescence, while the characteristic absorption spectra and birefringence of CR represent more rigid criteria for the presence of amyloid fibrils. Therefore, it seemed reasonable to use both these dyes simultaneously, combining the advantages of each technique. To this end, we undertook a detailed analysis of the fluorescence spectral behavior of these unique amyloid tracers upon their binding to amyloid fibrils from lysozyme, insulin and an N-terminal fragment of apolipoprotein A-I with Iowa mutation. The fluorescence measurements revealed several criteria for distinguishing between fibrillar and monomeric protein states: (i) a common drastic increase in ThT fluorescence intensity; (ii) a sharp decrease in ThT fluorescence upon addition of CR; (iii) an appearance of the maximum at 535–540 nm in the CR excitation spectra; (iv) increase in CR fluorescence intensity at 610 nm. Based on these findings we designed a novel combined ThT–CR fluorescence assay for amyloid identification. Such an approach not only strengthens the reliability of the ThT assay, but also provides new opportunities for structural characterization of amyloid fibrils.

  18. In vitro selection of an effective fungicide against Armillaria mellea and control of white root rot of grapevine in the field.

    Science.gov (United States)

    Aguín, Olga; Mansilla, J Pedro; Sainz, María J

    2006-03-01

    Armillaria mellea (Vahl ex Fr) Kummer is an aggressive pathogen which causes white root rot in a wide range of hosts. Most chemicals tested so far against Armillaria, both in vitro and in the field, have not been effective in reducing fungal growth and/or preventing plant decline and mortality. In the present work the effects of four DMI (sterol demethylation inhibitor) fungicides, cyproconazole, hexaconazole, propiconazole and tetraconazole, and another six downwardly mobile systemic chemicals, azoxystrobin, cubiet (copper bis(ethoxy-dihydroxy-diethylamino)sulfate), fosetyl-Al, potassium phosphite, sodium tetrathiocarbonate (STTC) and 2-(thiocyanomethylthio)benzothiazole (TCMTB), on the mycelial growth of A. mellea were compared and evaluated; the product yielding the best results in in vitro experiments was selected to determine its efficacy in preventing decline and mortality of grapevines in the field. Best results on in vitro fungal growth reduction were obtained with the four azoles tested, in particular with cyproconazole and hexaconazole, achieving 67-72% mycelial growth inhibition at the lowest dose. Results obtained in the field showed that a dose of 50 mg AI litre(-1) of cyproconazole once or twice a year was efficient in controlling the disease even in vines seriously affected by the pathogen. However, further research is required to study minimum effective doses, residual effects and the convenience of the application of annual dressings in damaged vineyards, so as to gradually reduce the pathogen inoculum potential in soil and control the disease while reducing chemical residues in the plant and preventing development of fungal resistance. PMID:16475239

  19. Guatemalan potato moth Tecia solanivora distinguish odour profiles from qualitatively different potatoes Solanum tuberosum L.

    Science.gov (United States)

    Karlsson, Miriam Frida; Birgersson, Göran; Witzgall, Peter; Lekfeldt, Jonas Duus Stevens; Nimal Punyasiri, P A; Bengtsson, Marie

    2013-01-01

    Guatemalan potato moth, Tecia solanivora, lay eggs in the soil nearby potato Solanum spp. and larvae feed on the tubers. We investigated the oviposition behaviour of T. solanivora females and the survival of larval offspring on healthy vs. stressed, i.e. light exposed and/or damaged potato tubers. In choice tests, females laid significantly more eggs in response to potato odour of healthy tubers and female oviposition preference correlated with higher larval survival. Survival of larvae was negatively correlated with the tuber content of the steroid glycoalkaloids α-solanine and α-chaconine: healthy potatoes contained lower amounts than stressed tubers, ranging from 25 to 500 μg g⁻¹ and from 30 to 600 μg g⁻¹, respectively. Analysis of volatile compounds emitted by potato tubers revealed that stressed tubers could clearly be distinguished from healthy tubers by the composition of their volatile profiles. Compounds that contributed to this difference were e.g. decanal, nonanal, isopropyl myristate, phenylacetaldehyde, benzothiazole, heptadecane, octadecane, myristicin, E,E-α-farnesene and verbenone. Oviposition assays, when female moths were not in contact with the tubers, clearly demonstrated that volatiles guide the females to lay fewer eggs on stressed tubers that are of inferior quality for the larvae. We propose that volatiles, such as sesquiterpenes and aldehydes, mediate oviposition behaviour and are correlated with biosynthetically related, non-volatile compounds, such as steroidal glycoalkaloids, which influence larval survival. We conclude that the oviposition response and larval survival of T. solanivora on healthy vs. stressed tubers supports the preference performance hypothesis for insect herbivores.

  20. Microbiological and physicochemical analysis of pumpkin juice fermentation by the basidiomycetous fungus Ganoderma lucidum.

    Science.gov (United States)

    Zhao, Jing; Liu, Wei; Chen, Dong; Zhou, Chunli; Song, Yi; Zhang, Yuyu; Ni, Yuanying; Li, Quanhong

    2015-02-01

    A new protocol for processing of pumpkin juice was set up which included fermentation by the basidiomycete Ganoderma lucidum at 28 °C for 7 d. The growth curve of G. lucidum in pumpkin juice was successfully (R(2)  = 0.99) fitted by a 4-parameter logistic model and the ideal highest biomass was estimated to be 4.79 g/L. G. lucidum was found to have a significant acidification effect on pumpkin juice. The lowest pH (4.05 ± 0.05) and highest total titratable acidity (14.31 ± 0.16 mL 0.1 M NaOH/100 mL) were found on the 4th day during fermentation. Sugars in pumpkin juice fermented with G. lucidum showed a significant decrease, especially glucose and fructose. On the contrary, the release of exo-polysaccharides and free amino acids greatly enriched the pumpkin juice. The variation of color index and viscosity also mirrored the above behavior. Based on headspace solid phase microextraction and gas chromatography-mass spectrometry, 68 volatile compounds were identified, including 17 esters, 14 alcohols, 13 phenyl compounds, 11 aldehydes, 8 ketones, 3 acids, 1 furan, and 1 benzothiazole. The pumpkin juices fermented for different days were markedly differentiated with principal component analysis and the fermentation process was tentatively divided into 3 periods: the booming (from the 1st to 4th day), steady (from the 5th to 6th day), and decline (the 7th day) period. PMID:25586306

  1. Microbiological and physicochemical analysis of pumpkin juice fermentation by the basidiomycetous fungus Ganoderma lucidum.

    Science.gov (United States)

    Zhao, Jing; Liu, Wei; Chen, Dong; Zhou, Chunli; Song, Yi; Zhang, Yuyu; Ni, Yuanying; Li, Quanhong

    2015-02-01

    A new protocol for processing of pumpkin juice was set up which included fermentation by the basidiomycete Ganoderma lucidum at 28 °C for 7 d. The growth curve of G. lucidum in pumpkin juice was successfully (R(2)  = 0.99) fitted by a 4-parameter logistic model and the ideal highest biomass was estimated to be 4.79 g/L. G. lucidum was found to have a significant acidification effect on pumpkin juice. The lowest pH (4.05 ± 0.05) and highest total titratable acidity (14.31 ± 0.16 mL 0.1 M NaOH/100 mL) were found on the 4th day during fermentation. Sugars in pumpkin juice fermented with G. lucidum showed a significant decrease, especially glucose and fructose. On the contrary, the release of exo-polysaccharides and free amino acids greatly enriched the pumpkin juice. The variation of color index and viscosity also mirrored the above behavior. Based on headspace solid phase microextraction and gas chromatography-mass spectrometry, 68 volatile compounds were identified, including 17 esters, 14 alcohols, 13 phenyl compounds, 11 aldehydes, 8 ketones, 3 acids, 1 furan, and 1 benzothiazole. The pumpkin juices fermented for different days were markedly differentiated with principal component analysis and the fermentation process was tentatively divided into 3 periods: the booming (from the 1st to 4th day), steady (from the 5th to 6th day), and decline (the 7th day) period.

  2. An investigation on the inhibitory action of benzazole derivatives as a consequence of sulfur atom induction

    Energy Technology Data Exchange (ETDEWEB)

    Moradi, Z.; Attar, M.M., E-mail: attar@aut.ac.ir

    2014-10-30

    Highlights: • The inhibitory behavior of three benzazole based molecules was studied. • Weight loss and EIS technique revealed a marked difference between three molecules’ potential inhibitory actions, although having the same adsorption isotherm. • AFM and contact angle measurements showed a decrease in roughness and hydrophillicity as a result of introducing sulfur which was related to better adsorption of the molecule and formation of more integrated inhibitor film. • The most constant results was obtained by HF method with 6-31G (d,p) basis set in water medium. - Abstract: The inhibitory action of three benzazole based molecules namely 2-methyl benzimidazole (2-MBI), 2-methyl benzothiazole (2-MBT) and 2-mercapto benzthiazole (2-SHBT) in 1 M HCl solution was studied by gravimetric analysis and electrochemical impedance spectroscopy (EIS). Results showed that the inhibitor adsorption on the iron surface was according to Langmuir adsorption isotherm for 2-MBI and 2-MBT and Flory Huggins Isotherm for 2-SHBT. Surface roughness obtained by Atomic Forced Microscopy (AFM) revealed that a good inhibitor decreases the surface roughness significantly which can be related to the formation of more integrated molecular film of inhibitor on steel surface. Based on contact angle (CA) measurements as the efficiency of the inhibitor molecules improve the hydrophobicity increases. These three molecules were chosen to see the effect of introducing sulfur atom into the structure the main effect of which would be on electronic parameters. To better understand this effect, the quantum chemical descriptors including: E{sub HOMO}, E{sub LUMO}, energy gap (ΔE), dipole moment (μ), hardness (η), softness (σ), electronegativity index (χ), fraction of electrons transferred (ΔN), that are most relevant to the potential action of a molecule as corrosion inhibitor, have been calculated in water and vacuum. Electronic parameters of these three inhibitors have been studied using

  3. Influence of Dopant Concentration on Electroluminescent Performance of Organic White-Light-Emitting Device with Double-Emissive-Layered Structure

    Institute of Scientific and Technical Information of China (English)

    WU Xiao-Ming; HUA Yu-Lin; YIN Shou-Gen; ZHANG Li-Juan; WANG Yu; HOU Qing-Chuan; ZHANG Jun-Mei

    2008-01-01

    A novel phosphorescent organic white-light-emitting device(WOLED)with configuration of ITO/NPB/CBP:TBPe:rubrene/Zn(BTZ)2:Ir(piq)2(acac)/Zn(BTZ)2/Mg:Ag is fabricated successfully,where the phosphorescent dye bis(1-(phenyl)isoquinoline)iridium(Ⅲ)acetylanetonate(Ir(piq)2(acac))doped into bis-(2-(2-hydroxyphenyl)benzothiazole)zinc(Zn (BTZ)2)(greenish-blue emitting material with electron transport character)as the red emitting layer,and fluorescent dye2,5,8,11-tetra-tertbutylperylene(TBPe)and5,6,11,12-tetraphenyl-naphthacene(rubrene)together doped into 4,4'-N,N'-dicarbazole-biphenyl(CBP)(ambipolar conductivity material)as the blue-orange emitting layer,respectively.The two emitting layers are sandwiched between the hole-transport layer N,N'-biphenyl-N,N'-bis(1-naphthyl)-(1,1'-biphenyl)-4,4'-diamine(NPB)and electron-transport layer(Zn(BTZ)2).The optimum device turns on at the driving voltage of 4.5V.A maximum external quantum efficiency of 1.53%and brightness 15000 cd/m2 are presented.The best point of the Commission Internationale de l'Eclairage(CIE)coordinates locates at (0.335,0.338)at about 13 V. Moreover,we also discuss how to achieve the bright pure white light through optimizing the doping concentration of each dye from the viewpoint of energy transfer process.

  4. Targeting DNA with "light-up" pyrimidine triple-helical forming oligonucleotides conjugated to stabilizing fluorophores (LU-TFOs).

    Science.gov (United States)

    Renard, Brice-Loïc; Lartia, Rémy; Asseline, Ulysse

    2008-12-01

    The synthesis of triple-helix-forming oligonucleotides (TFOs) linked to a series of cyanine monomethines has been performed. Eight cyanines including one thiocyanine, four thiazole orange analogues, and three quinocyanines were attached to the 5'-end of 10-mer pyrimidine TFOs. The binding properties of these modified TFOs with their double-stranded DNA target were studied by absorption and steady-state fluorescence spectroscopy. The stability of the triplex structures depended on the cyanine structure and the linker size used to connect both entities. The most efficient cyanines able to stabilize the triplex structures, when attached at the 5'-end of the TFO, have been incorporated at both ends and provided triplex structures with increased stability. Fluorescence studies have shown that for the TFOs involving one cyanine, an important intensity increase (up to 37-fold) in the fluorescent signal was observed upon their hybridization with the double-stranded target, proving hybridization. The conjugates involving thiazole orange attached by the benzothiazole ring provided the most balanced properties in terms of triplex stabilization, fluorescence intensity and fluorescence enhancement upon hybridization with the double-stranded target. In order to test the influence of different parameters such as the TFO sequence and length, thiazole orange was used to label 17-mer TFOs. Hybridizations of these TFOs with different duplexes, designed to study the influence of mismatches at both internal and terminal positions on the triplex structures, confirmed the possibility of triplex formation without loss of specificity together with a strong fluorescence enhancement (up to 13-fold). PMID:19005602

  5. Membrane bioreactors for municipal wastewater treatment - a viable option to reduce the amount of polar pollutants discharged into surface waters?

    Science.gov (United States)

    Weiss, Stefan; Reemtsma, Thorsten

    2008-08-01

    The potential of a lab-scale membrane bioreactor (MBR) to remove polar pollutants from municipal wastewater was studied for industrial and household chemicals over a period of 22 months parallel to a conventional activated sludge (CAS) treatment. For half of the compounds, such as benzotriazole, 5-tolyltriazole (5-TTri), benzothiazole-2-sulfonate and 1,6-naphthalene disulfonate (1,6-NDSA), removal by MBR was significantly better than in CAS, while no improvement was recorded for the other half (1,5-NDSA, 1,3-NDSA, 4-TTri and naphthalene-1-sulfonate). The influence of operational conditions on trace pollutant removal by MBR was studied but no significant effects were found for variation of hydraulic retention time (7h-14h) and sludge retention time (26d-102d), suggesting that the lowest values selected have already been high enough for good removal. It is shown that the seemingly inconsistent results reported here and in previous studies regarding the comparison of trace pollutant removal in MBR and CAS are highly consistent. MBR is neither superior for well degradable compounds that are already extensively degraded in CAS treatment nor for recalcitrant compounds that are not amenable to biodegradation. For most compounds of intermediate removal in CAS treatment (15-80%), among them pharmaceuticals, personal care products and industrial chemicals, the MBR is clearly superior and reduces the effluent concentration by 20-50%. Despite of this clear benefit of MBR, the effect is not pronounced enough to serve as a sole argument for employing MBR in municipal wastewater treatment. PMID:18684484

  6. Gadolinium Nanoparticles Conjugated with Therapeutic Bifunctional Chelate as a Potential T1 Theranostic Magnetic Resonance Imaging Agent.

    Science.gov (United States)

    Kang, Min-Kyoung; Lee, Gang Ho; Jung, Ki-Hye; Jung, Jae-Chang; Kim, Hee-Kyung; Kim, Yeon-Hee; Lee, Jongmin; Ryeom, Hun-Kyu; Kim, Tae-Jeong; Chang, Yongmin

    2016-05-01

    This work is directed toward the synthesis of two types of gadolinium oxide nanoparticles (Gd-oxide NPs), abbreviated as Gd@SiO2-DO3A and Gd@SiO2-DO2A-BTA, with diameters of 50-60 nm. The synthesis involves sequential coating of Gd-oxide NPs with tetraethyl orthosilicate (TEOS) and (3-aminopropyl) triethoxysilane (APTES), followed by functionalization of the aminopropylsilane group with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) or 1,4,7,10-tetraazacyclododecane-1,4,7-trisacetic acid conjugates of benzothiazoles (DO3A-BTA). Gd@SiO2-DO3A and Gd@SiO2-DO2A-BTA exhibit high water solubility and colloidal stability. The r1 relaxivities of both Gd@SiO2-DO3A and Gd@SiO2-DO2A-BTA are higher than those of the corresponding low-molecular-weight magnetic resonance imaging contrast agents (MRI CAs), and their r2/r1 ratios are close to 1, indicating that both can be used as potential T1 MRI CAs. Biodistribution studies demonstrated that Gd@SiO2-DO2A-BTA was excreted via both hepatobiliary and renal pathways. Gd@SiO2-DO2A-BTA exhibits a strong intracellular uptake property in a series of tumor cell lines, and has significant anticancer characteristics against cell lines such as SK-HEP-1, MDA-MB-231, HeLa, and Hep-3B. PMID:27305813

  7. Infrared and Raman spectra of bicyclic molecules using scaled noncorrelated and correlated {ital ab initio} force fields

    Energy Technology Data Exchange (ETDEWEB)

    Collier, W.B. [Department of Chemistry, Oral Roberts University, Tulsa, Oklahoma 74171 (United States); Magdo, I. [Gedeon Richter Ltd., Molecular Design Unit, P.O. Box 27, H-1475, Budapest (Hungary); Klots, T.D. [Bartlesville Thermodynamic Group, BDM Petroleum Technologies, P.O. Box 2543, Bartlesville, Oklahoma 74005 (United States)

    1999-03-01

    This paper reports the application of a scaled {ital ab initio} calculated harmonic force field to predict the frequencies, infrared intensities, Raman intensities, and depolarization ratios of benzofuran, benzothiophene, indole, benzothiazole, and benzoxazole. The theoretical calculations were made using the Hartree{endash}Fock HF/3-21G{sup {asterisk}} and HF/6-31G{sup {asterisk}} basis sets and density-functional theory (DFT)B3-LYP/6-31G{sup {asterisk}} levels. The equilibrium calculated force constants are scaled according to the method of Pulay and compared with the experimentally determined frequencies, intensities, and depolarization ratios to assess the accuracy and fit of the theoretical calculation. Methods for quantitative comparison of intensities were developed. The double numerical differentiation algorithm of Komornicki and McIver was analyzed and used to calculate the Raman intensities for the (DFT)B3-LYP/6-31G{sup {asterisk}} model. The (DFT)B3-LYP/6-31G{sup {asterisk}} model is approaching the harmonic limit in the planar and nonplanar refinement of these bicyclics with wave number fits of 5 and 4 cm{sup {minus}1}, respectively. It reduces the need for scale factors and increases their transfer accuracy, largely because the scale factors values cluster near unity. The Komornicki and McIver algorithm is still a viable method for calculating Raman intensity information for methods that do not have analytic routines programmed. The main shortcoming to this method may lie in the tighter self-consistent field (SCF) convergence criterion possibly needed to calculate Raman intensities for the totally symmetric modes of large molecules. The (DFT)B3-LYP/6-31G{sup {asterisk}} model was superior for calculating the planar intensities, but equal to the HF methods for predicting the nonplanar intensities. {copyright} {ital 1999 American Institute of Physics.}

  8. Synthesis and light-emitting properties of organic electroluminescent compounds and their metal complexes

    Institute of Scientific and Technical Information of China (English)

    CUI Jianzhong; Kim Sung-Hoon

    2004-01-01

    Several organic electroluminescent (EL) compounds, 2,2′-(1,4-phenylenedivinylene)bis-3,3-dimethyl-in- dolenine (1), 2,2′-(1,4-phenylenedivinylene)bis-benzoxazole (2), 2,2′-(1,4-phenylenedivinylene)bis-benzothiazole (3), 4,4′- (1,4-phenylenedivinylene)bis-quinoline (4), 2,2′-(1,4-phenyle- nedivinylene)bis-quinoline (5), 2,2′-(1,4-phenylenedivinyle- ne)bis-1,3,3-trimethyl-indolenine dichlo ride (6), 2,2′-(1,4- phenylene-divinylene)bis-1-hydro-3,3-dimethyl-indolenine dichloride (7), 2,2′-(1,4-phenylenedivinylene)bis-8-acetoxy- quinoline (8), 2,2′-(1,4-phenylenedivinylene)bis-8-hydroxyq- uinoline (9) and metal complexes of 9, Al(PHQ) (10) and Zn(PHQ) (11), have been synthesized and characterized. The crystal structure of 6 was determined. Light emitting properties of the prepared compounds have been investigated. 1 produces an orange-yellow emission (λmax = 575 nm). The cation, 6, gives a red emission (λmax = 607 nm), which is shifted 32 nm to the red compared to 1. 8 produces a yellow emission (λmax = 567 nm). The metal complex 10 gives a red emission (λmax = 610 nm), which is a red shift of 43 nm compared to 8. The change in structure in the prepared compound caused a change in the electron distribution in the compounds, which induces a large wavelength shift of the emitted-light. Thermal analysis showed that the decomposition temperatures of the metal complexes (10, 11) were higher than those for the smaller organic molecular compounds (1-9). Therefore, metal complexes (10, 11) can be used as EL materials over a larger temperature range.

  9. Modulating the near-infrared luminescence of neodymium and ytterbium complexes with tridentate ligands based on benzoxazole-substituted 8-hydroxyquinolines.

    Science.gov (United States)

    Shavaleev, Nail M; Scopelliti, Rosario; Gumy, Frédéric; Bünzli, Jean-Claude G

    2009-04-01

    An improved synthesis of 2-(2'-benzothiazole)- and 2-(2'-benzoxazole)-8-hydroxyquinoline ligands that combine a tridentate N,N,O-chelating unit for metal binding and extended chromophore for light harvesting is developed. The 2-(2'-benzoxazole)-8-hydroxyquinoline ligands form mononuclear nine-coordinate complexes with neodymium, [Nd(kappa(3)-ligand)(3)], and an eight-coordinate complex with ytterbium, [Yb(kappa(3)-ligand)(2) x (kappa(1)-ligand) x H(2)O], as verified by crystallographic characterization of five complexes with four different ligands. The chemical stability of the complexes increases when the ligand contains 5,7-dihalo-8-hydroxyquinoline versus an 8-hydroxyquinoline group. The complexes feature a ligand-centered visible absorption band with a maximum at 508-527 nm and an intensity of (7.5-9.6) x 10(3) M(-1) x cm(-1). Upon excitation with UV and visible light within ligand absorption transitions, the complexes display characteristic lanthanide luminescence in the near-infrared at 850-1450 nm with quantum yields and lifetimes in the solid state at room temperature as high as 0.33% and 1.88 micros, respectively. The lanthanide luminescence in the complexes is enhanced upon halogenation of the 5,7-positions in the 8-hydroxyquinoline group and upon the addition of electron-donating substituents to the benzoxazole ring. Facile modification of chromophore units in 2-(2'-benzoxazole)-8-hydroxyquinoline ligands provides means for controlling the luminescence properties of their lanthanide complexes.

  10. Excitation spectra of aromatic molecules within a real-space G W -BSE formalism: Role of self-consistency and vertex corrections

    Science.gov (United States)

    Hung, Linda; da Jornada, Felipe H.; Souto-Casares, Jaime; Chelikowsky, James R.; Louie, Steven G.; Ã-ǧüt, Serdar

    2016-08-01

    We present first-principles calculations on the vertical ionization potentials (IPs), electron affinities (EAs), and singlet excitation energies on an aromatic-molecule test set (benzene, thiophene, 1,2,5-thiadiazole, naphthalene, benzothiazole, and tetrathiafulvalene) within the G W and Bethe-Salpeter equation (BSE) formalisms. Our computational framework, which employs a real-space basis for ground-state and a transition-space basis for excited-state calculations, is well suited for high-accuracy calculations on molecules, as we show by comparing against G0W0 calculations within a plane-wave-basis formalism. We then generalize our framework to test variants of the G W approximation that include a local density approximation (LDA)-derived vertex function (ΓLDA) and quasiparticle-self-consistent (QS) iterations. We find that ΓLDA and quasiparticle self-consistency shift IPs and EAs by roughly the same magnitude, but with opposite sign for IPs and the same sign for EAs. G0W0 and QS G W ΓLDA are more accurate for IPs, while G0W0ΓLDA and QS G W are best for EAs. For optical excitations, we find that perturbative G W -BSE underestimates the singlet excitation energy, while self-consistent G W -BSE results in good agreement with previous best-estimate values for both valence and Rydberg excitations. Finally, our work suggests that a hybrid approach, in which G0W0 energies are used for occupied orbitals and G0W0ΓLDA for unoccupied orbitals, also yields optical excitation energies in good agreement with experiment but at a smaller computational cost.

  11. C16, a novel advanced glycation endproduct breaker, restores cardiovascular dysfunction in experimental diabetic rats

    Institute of Scientific and Technical Information of China (English)

    Gang CHENG; Li-li WANG; Wen-sheng QU; Long LONG; Hao CUI; Hong-ying LIU; Ying-lin CAO; Song LI

    2005-01-01

    Aim: Advanced glycation endproducts (AGE) have been implicated in the pathogenesis of diabetic complications, including diabetic cardiovascular dysfunction.3-[2-(4-Bromo-phenyl)- 1-methyl-2-oxo-ethyl]-4,5,6,7-tetrahydro-benzothiazol-3-ium bromide (C16), a novel AGE breaker, was investigated for its effects on the development of cardiovascular disease in diabetic rats. Methods: Rats that had streptozotocin-induced diabetes for 12 weeks were divided into groups receiving C16 or vehicle by gavage. Results: In hemodynamic studies of the left ventricle,C16 treatment (25 or 50 mg/kg) for 4 weeks resulted in a significant increase in left ventricular systolic pressure, +dp/dtmax, and -dp/dtmax as compared with vehicletreated diabetic rats. Furthermore, in hemodynamic studies of the cardiovascular system, C16 (12.5, 25, or 50 mg/kg) treatment for 4 weeks resulted in a dosedependent and significant increase in cardiac output, a reduction of total peripheral resistance, and an increase in systemic arterial compliance when compared with vehicle-treated diabetic rats. Biochemical studies showed that C16 treatment also resulted in a significant decrease in immunoglobulin G-red blood cell surface crosslink content and an increase in collagen solubility. Morphological and immunohistochemical examinations indicated that C 16 was able to prevent increases of the collagen type Ⅲ/Ⅰ ratio in the aorta and decrease the accumulation of AGE in the aorta. Conclusion: C16 has the ability to reduce AGE accumulation in tissues in vivo, and can restore diabetes-associated cardiovascular disorders in rats. This provides a potential therapeutic approach for cardiovascular disease associated with diabetes and aging in humans.

  12. Thioflavin T derivatives for the characterization of insulin and lysozyme amyloid fibrils in vitro: Fluorescence and quantum-chemical studies

    Energy Technology Data Exchange (ETDEWEB)

    Vus, Kateryna, E-mail: kateryna_vus@yahoo.com [Department of Nuclear and Medical Physics, V.N. Karazin Kharkiv National University, 4 Svobody Sq., Kharkiv 61022 (Ukraine); Trusova, Valeriya; Gorbenko, Galyna [Department of Nuclear and Medical Physics, V.N. Karazin Kharkiv National University, 4 Svobody Sq., Kharkiv 61022 (Ukraine); Sood, Rohit; Kinnunen, Paavo [Department of Biomedical Engineering and Computational Science, School of Science and Technology, Aalto University, FI-00076 Espoo (Finland)

    2015-03-15

    Two charged Thioflavin T (ThT) derivatives, referred to here as ICT2 and ICT3, showed higher fluorescence response, association constants and the blue-shifted emission maxima in the presence of lysozyme fibrils compared to insulin aggregates. In turn, the other two ThT derivatives, ICT4 and ICT5, possessed much weaker sensitivity to amyloid fibrils. Furthermore, a direct correlation was found between the “light-up” ability of the fibril-bound fluorophores and those observed in concentrated dichlormethane or glycerol solutions. To explain this behavior, the ground and lowest non-relaxed excited state properties of the dyes were evaluated with the 6-31G(d,p) basis set, using DFT and the CIS method. The excited state energy dependences along the torsion angle between the benzothiazole and phenyl moieties of the ICT4, ICT5 turned out to have three directly observed minima, corresponding to the locally excited (LE) and twisted intramolecular charge transfer (TICT) states. Thus, stronger stabilization of the ICT4, ICT5 LE states resulted in significantly greater quantum yield of these dyes in buffer solution and the absence of the “light-up” feature in the presence of insulin amyloid fibrils, compared to ICT2 and ICT3. - Highlights: • The ThT derivatives–ICT{sub 2}, ICT{sub 3} had the sensitivity to lysozyme fibrillar aggregates. • The insulin fibril (InsF)-bound ICT{sub 2}, ICT{sub 3} showed higher fluorescence intensities. • The lysozyme fibril-bound dyes have blue-shifted emission maxima compared to InsF. • Fluorescence of the fibril-bound dyes strongly correlates with that in glycerol. • The propylamine/metoxy moieties → the stabilization of the LE state of ICT4/ICT5. • Such a stabilization → the weak dye sensitivity to the environmental factors.

  13. Combined thioflavin T-Congo red fluorescence assay for amyloid fibril detection

    Science.gov (United States)

    Girych, Mykhailo; Gorbenko, Galyna; Maliyov, Ivan; Trusova, Valeriya; Mizuguchi, Chiharu; Saito, Hiroyuki; Kinnunen, Paavo

    2016-09-01

    Fluorescence represents one of the most powerful tools for the detection and structural characterization of the pathogenic protein aggregates, amyloid fibrils. The traditional approaches to the identification and quantification of amyloid fibrils are based on monitoring the fluorescence changes of the benzothiazole dye thioflavin T (ThT) and absorbance changes of the azo dye Congo red (CR). In routine screening it is usually sufficient to perform only the ThT and CR assays, but both of them, when used separately, could give false results. Moreover, fibrillization kinetics can be measured only by ThT fluorescence, while the characteristic absorption spectra and birefringence of CR represent more rigid criteria for the presence of amyloid fibrils. Therefore, it seemed reasonable to use both these dyes simultaneously, combining the advantages of each technique. To this end, we undertook a detailed analysis of the fluorescence spectral behavior of these unique amyloid tracers upon their binding to amyloid fibrils from lysozyme, insulin and an N-terminal fragment of apolipoprotein A-I with Iowa mutation. The fluorescence measurements revealed several criteria for distinguishing between fibrillar and monomeric protein states: (i) a common drastic increase in ThT fluorescence intensity; (ii) a sharp decrease in ThT fluorescence upon addition of CR; (iii) an appearance of the maximum at 535-540 nm in the CR excitation spectra; (iv) increase in CR fluorescence intensity at 610 nm. Based on these findings we designed a novel combined ThT-CR fluorescence assay for amyloid identification. Such an approach not only strengthens the reliability of the ThT assay, but also provides new opportunities for structural characterization of amyloid fibrils.

  14. Excited-state intramolecular proton transfer (ESIPT) inspired azole-quinoline based fluorophores: Synthesis and photophysical properties study

    Energy Technology Data Exchange (ETDEWEB)

    Padalkar, Vikas S.; Sekar, Nagaiyan, E-mail: n.sekar@ictmumbai.edu.in

    2014-11-15

    7-Hydroxy-3-(4-nitrophenyl)quinoline-6-carboxylic acid was obtained by the condensation reaction of p-amino salicylic acid and 4-nitrophenylmalonadialdehyde which was obtained from phenylacetonitrile through nitration, hydrolysis and Vilsmeier reaction. 7-Hydroxy-3-(4-nitrophenyl) quinoline-6-carboxylic acid was condensed with different o-aminophenols or o-aminothiophenol in ethanol in the presence of phosphorustrichloride. Synthesized quinoline contained benzimidazole and benzothiazole moieties. Photophysical behaviors of these compounds in solvents of different polarities were studied using UV–vis and fluorescence spectroscopy. The compounds showed single absorption in all the studied solvents. The dual emissions (normal emission and ESIPT emission) as well as large Stokes' shift emission pattern were observed for the synthesized fluorophores. The photophysical study shows that the emission properties of the compounds depend on the solvent polarity. The photophysical properties of the compounds were compared with structurally analogous ESIPT quinoline. Thermal stability of the compounds was studied using thermogravimetric analysis and results show that compounds are thermally stable up to 300 °C. The synthesized quinoline derivatives were characterized using elemental analysis, FT-IR and {sup 1}H –NMR, {sup 13}C –NMR spectroscopy and mass spectral analysis. - Highlights: • First and unique study of quinoline derivatives contain ESIPT azole unit at 6-position and hydroxyl group at 7-position. • Compounds are fluorescent with considerable quantum yields. • All compounds showed absorption in ultraviolet region and emission in visible region with large Stokes' shift. • The photophysical properties of new compounds were compared with reported ESIPT quinoline analogous.

  15. Solution processed single-emission layer white polymer light-emitting diodes with high color quality and high performance from a poly(N-vinyl)carbazole host.

    Science.gov (United States)

    Ye, Shang-Hui; Hu, Tian-Qing; Zhou, Zhou; Yang, Min; Quan, Mei-Han; Mei, Qun-Bo; Zhai, Bang-Cheng; Jia, Zhen-Hong; Lai, Wen-Yong; Huang, Wei

    2015-04-14

    Low cost and high performance white polymer light-emitting diodes (PLEDs) are very important as solid-state lighting sources. In this research three commercially available phosphors were carefully chosen, bis[2-(4,6-difluorophenyl)pyridinato-N,C(2)](picolinate)iridium(III) (FIrpic), bis[2-(2-pyridinyl-N)phenyl-C](2,4-pentanedionato-O(2),O(4))iridium(III) [Ir(ppy)2(acac)], and bis(2-phenyl-benzothiazole-C(2),N)(acetylacetonate)iridium(III) [Ir(bt)2(acac)], plus a home-made red phosphor of tris[1-(2,6-dimethylphenoxy)-4-(4-chlorophenyl)phthalazine]iridium(III) [Ir(MPCPPZ)3], and their photophysical and morphological properties were systematically studied as well as their applications in single-emission layer white PLEDs comprising poly(N-vinylcarbazole) as host. Additionally, the electrochemical properties and energy level alignment, possible energy transfer process, and thin-film morphology were also addressed. The binary blue/orange complementary white PLEDs exhibit stable electroluminescence spectra, wide spectrum-covering region range from 380-780 nm, and high color rendering index (CRI) over 70 with Commission Internationale de l'Eclairage coordinates x,y (CIEx,y) of (0.388, 0.440), correlated color temperature (CCT) of around 4400, plus high efficiency of 25.5 cd A(-1). The optimized red-green-blue white PLEDs showed a satisfactory CRI of around 82.4, maximum current efficiency of 20.0 cd A(-1) and external quantum efficiency (EQE) of 10.8%, corresponding to a CCT of 3700-2800, which is a warm-white hue. At last, stable and high color quality, red-green-orange-blue four component white PLEDs, with a CRI of over 82, a high efficiency of 24.0 cd A(-1), EQE of 11.5%, and high brightness of 43,569.9 cd m(-2) have been obtained. PMID:25742776

  16. Neurotoxic injury pathways in differentiated mouse motor neuron–neuroblastoma hybrid (NSC-34D) cells in vitro—Limited effect of riluzole on thapsigargin, but not staurosporine, hydrogen peroxide and homocysteine neurotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Hemendinger, Richelle A., E-mail: richelle.hemendinger@carolinashealthcare.org [ALS Translational Neuroscience Laboratory, Carolinas Medical Center, Charlotte, NC 28203 (United States); Carolinas Neuromuscular/ALS-MDA Center, Department of Neurology, Carolinas Medical Center, Charlotte, NC 28203 (United States); Armstrong, Edward J. [ALS Translational Neuroscience Laboratory, Carolinas Medical Center, Charlotte, NC 28203 (United States); Carolinas Neuromuscular/ALS-MDA Center, Department of Neurology, Carolinas Medical Center, Charlotte, NC 28203 (United States); Radio, Nick [ThermoScientific, Pittsburgh, PA (United States); Brooks, Benjamin Rix [ALS Translational Neuroscience Laboratory, Carolinas Medical Center, Charlotte, NC 28203 (United States); Carolinas Neuromuscular/ALS-MDA Center, Department of Neurology, Carolinas Medical Center, Charlotte, NC 28203 (United States); University of North Carolina School of Medicine-Charlotte Campus (United States)

    2012-01-15

    The neuroblastoma–spinal motor neuron fusion cell line, NSC-34, in its differentiated form, NSC-34D, permits examining the effects of riluzole, a proven treatment for amyotrophic lateral sclerosis (ALS) on cell death induction by staurosporine (STS), thapsigargin (Thaps), hydrogen peroxide (H{sub 2}O{sub 2}) and homocysteine (HCy). These neurotoxins, applied exogenously, have mechanisms of action related to the various proposed molecular pathogenetic pathways in ALS and are differentiated from endogenous cell death that is associated with cytoplasmic aggregate formation in motor neurons. Nuclear morphology, caspase-3/7 activation and high content imaging were used to assess toxicity of these neurotoxins with and without co-treatment with riluzole, a benzothiazole compound with multiple pharmacological actions. STS was the most potent neurotoxin at killing NSC-34D cells with a toxic concentration at which 50% of maximal cell death is achieved (TC{sub 50} = 0.01 μM), followed by Thaps (TC{sub 50} = 0.9 μM) and H{sub 2}O{sub 2} (TC{sub 50} = 15 μM) with HCy requiring higher concentrations to kill at the same level (TC{sub 50} = 2200 μM). Riluzole provided neurorescue with a 20% absolute reduction (47.6% relative reduction) in apoptotic cell death against Thaps-induced NSC-34D cell (p ≤ 0.05), but had no effect on STS-, H{sub 2}O{sub 2}- and HCy-induced NSC-34D cell death. This effect of riluzole on Thaps induction of cell death was independent of caspase-3/7 activation. Riluzole mitigated a toxin that can cause intracellular calcium dysregulation associated with endoplasmic reticulum (ER) stress but not toxins associated with other cell death mechanisms. -- Highlights: ► Calcium-dependent neurotoxins are potent cell death inducers in NSC-34D cells. ► Riluzole provides neurorescue against Thaps-induced NSC-34D cell death. ► Riluzole had no effect on neurotoxicity by STS, H{sub 2}O{sub 2} and Hcy. ► Riluzole reduces NSC-34D cell death independent of

  17. 舍饲与放养饲养方式下蕨麻猪肉的挥发性成分对比%Comparison of Volatile Components in Pork from Feedlot-raised and Pasture-raised Tibetan Miniature Pigs

    Institute of Scientific and Technical Information of China (English)

    孙志昶; 韩玲; 李永鹏; 杨勤

    2011-01-01

    利用气相色谱质谱联用技术(GC—MS),研究甘肃甘南藏族自治州舍饲(谷物饲料)与放养(天然草料)6月龄蕨麻猪背最长肌中的挥发性风味化合物。两者的差异主要体现在醛类化合物上(舍饲组38.33%,放养组25.19%)。对于来源于美拉德反应的挥发性化合物而言,甲硫基丙醛(呈肉香)与苯并噻唑(呈肉汤味)在舍饲组的含量分别比放养组多23%和122%。舍饲组脂肪氧化产物总相对含量显著高于放养组(P〈0.05),且两组肉样中脂肪氧化产物的种类差异很大。放养组蕨麻猪肉中的萜类含量显著高于舍饲组(P〈0.05)。结果表明,%The volatile compounds in longissimus dorsi muscles from 6 month-old Tibetan miniature pigs raised in feedlot with cereal and on natural pasture from Gannan Tibetan Autonomous Prefecture, Gansu province were investigated by gas chromatography-mass spectrometry (GC-MS). Feedlot-raised and pasture-raised Tibetan miniature pigs mostly varied in their aldehyde contents (38.33% and 25.19%, respectively). Methylthiopropanal (meaty flavor) and benzothiazole (gravy flavor) that can be derived from Mailard reaction in feedlot-raised pork were 23% and 122% more than that in pasture-raised pork, respectively. Lipid oxidation products showed a significant increase in feedlot-raised pork as compared with their pasture-raised pork (P 〈 0.05), and a significant difference in the types of lipid oxidation products was also found. Pasture-raised pork exhibited significantly higher terpene content than feedlot-raised pork (P 〈 0.05). From these results, we concluded that raising methods can affect volatile compounds in pork from Tibetan miniature pig and therefore might affect pork flavor.

  18. A novel silver iodide metalo-drug: experimental and computational modelling assessment of its interaction with intracellular DNA, lipoxygenase and glutathione.

    Science.gov (United States)

    Banti, C N; Kyros, L; Geromichalos, G D; Kourkoumelis, N; Kubicki, M; Hadjikakou, S K

    2014-04-22

    The new mixed ligand silver(I) complex of formula [AgI(TPP)2(MBZT)] (1) was obtained by reacting 2-mercapto-benzothiazole (MBZT) with triphenylphosphine (TPP). The complex was characterized by m.p., vibrational spectroscopy (FT-IR), (1)H NMR, UV-vis, ESI-MS spectroscopic techniques and its structure was confirmed by X-ray crystallography. Mixed ligand complexes of silver(I) iodide with thiones and phosphines are very rare in the literature and to the best of our knowledge compound 1 is the first of this kind exhibiting significant biological effects. Complex 1 was evaluated for its in vitro cytotoxic activity (cell viability) under irradiation with UV light and without irradiation against human cancer cell lines: MCF-7 (breast, ER positive), MDA-MB-231 (breast, ER negative), Caki-1 (renal), A549 (lung), OAW-42 (ovarian), HeLa (cervical) and additionally against the normal human lung cell line MRC-5 (normal human fetal lung fibroblast cells) and normal immortalized human mammary gland epithelial cell line (MTSV17) with SRB assay. The results showed that 1 mediates a strong cytotoxic response to the tested normal and cancer cell lines. It exhibits equal activity against MDA-MB-231 cells where estrogen receptors (ERs) are devoid with the one against MCF-7 where ERs are present. Molecular docking studies have shown that 1 is docked in the different pocket than that of the ERs modulators. The binding affinity of 1 towards the intracellular molecules DNA and lipoxygenase (LOX) was studied for the evaluation of the mechanism of its cytostasis. The binding constant (Kb) of 1 towards CT-DNA was calculated by UV-Vis and fluorescent spectra suggesting intercalation or electrostatic interactions of 1 into DNA. Docking studies on DNA-complex interactions confirm the binding of 1. Moreover, the influence of complex 1 on the catalytic peroxidation of linoleic acid to hydroperoxylinoleic acid by the enzyme lipoxygenase (LOX) was kinetically and theoretically studied. In addition

  19. Response Surface Optimization of Maillard Reaction Conditions and Analysis of Volatile Flavor Compounds of MRPs Derived from the Hydrolysate of Pneumatophorus Japonicns Heads%响应面优化鲐鱼头酶解液Maillard反应条件及其产物挥发性风味物质分析

    Institute of Scientific and Technical Information of China (English)

    徐大伦; 束玉珍; 杨文鸽; 楼乔明; 薛长湖

    2013-01-01

    Using the enzymolysis from pneumatophorus japonicns head as raw material,the effects of xylose additives,reaction time and temperature on the sensory evaluation of Maillard reaction products (MRPs) were determined by response surface method.Then the volatile flavor components of MRPs were isolated and identified by GC-MS.The results showed that the optimum conditions of Maillard reaction were as follows:xylose 2.5%,Gly 1.6%,ginger pop 10%,at 117 ℃ for 55 min.73 kinds of volatile flavor component were obtained,in which 2-ethyl furan,2-pentyl furan,ω-Heptaldehyde,(Z)-4-Heptenal,(E)-2-Octenal,(E,E)-2,4-Decadienal,4-Ethylbenzaldehyde,3-ethyl-Phenol,4-pentylphenol,Benzothiazole,4-Methylthiazole,Dimethyl trisulfide had an important contribution to the MRPs flavor.%以鲐鱼头酶解液为原料,通过响应面法研究木糖添加量、反应温度和时间对鲐鱼头酶解液美拉德反应产物(MRPs)感官的影响.用GC-MS分离鉴定MRPs中的挥发性风味物质,结果表明:鲐鱼头酶解液Maillard反应条件是:木糖、甘氨酸、姜汁添加量分别为2.5%、1.6%和10%,117℃反应55 min.经GC-MS分析鉴定,MRPs共含73种挥发性物质,其中2-乙基呋喃、2-戊基呋喃、ω-庚醛、(Z)4-庚烯醛、(E)-2-辛烯醛、(E,E)-2,4-癸二烯醛、4-乙基苯甲醛、3-乙基苯酚、4-戊基苯酚、苯并噻唑、4-甲基噻唑和二甲基三硫化物等化合物对MRPs的风味有重要贡献.

  20. Occurrence of antifouling biocides in the Spanish Mediterranean marine environment.

    Science.gov (United States)

    Martínez, K; Ferrer, I; Hernando, M D; Fernández-Alba, A R; Marcé, R M; Borrull, F; Barceló, D

    2001-05-01

    A compilation of the results of a monitoring program of the recently used antifouling pesticides diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea), Irgarol 1051 (2-methylthio-4-tertiary-butylamino-6-cyclopropylamino-s-teiazine), seanine 211 (4,5-dichloro-2-n-octyl-4-isothazolin-3-one), chlorothalonil (2,4,5,6-tetrachloro-isophthalonitrile), dichlofluanid (N'-dimethyl-N-phenylsulphanamide), TCMTB ((2-thiocyanomethylthio) benzothiazole), and three degradation products demethyldiuron (3-(3,4-dichlorophenyl)-1-methylurea),3,4-dichlorophenylurea and 2-methylthio-4-tert-butylamino-s-triazine (Irgarol degradation product) that was carried out between April 1996 and February 2000 in enclosed seawaters from Catalonia and Almería (Spanish Mediterranean coast) is reported. Nine points were sampled along the Catalan coast: Barcelona Olympic port, Masnou, Blanes, Sant Carles de la Ràpita, Tarragona, Cambrils and Salou marinas as well as the Cambrils and Tarragona fishing harbors and in marinas and ports from Almeria: Aguadulce port, Almería port, Almerimar fishing harbour and Almerimar marina. The analytical methodologies were based on Solid Phase Extraction followed by liquid chromatography (LC) or gas chromatography (GC) coupled to a mass spectrometry (MS) or -Diode Array Detector. The main pollutants found in the sampled points were diuron and Irgarol 1051 that were detected at concentrations up to 2.19 micrograms l-1 and 0.33 microgram l-1, respectively. On the other hand, seanine 211 was found at the highest concentration (up to 3.7 micrograms l-1) during the summer of 1999. Low concentrations of dichlofluanid and the above mentioned degradation products were detected for the first time in the Spanish coasts. Chlorothalonil, TCMTB were not found at concentrations higher than 1 and 20 ng l-1 respectively which were the limit of determination (LOD) of the method for these compounds. In general the contamination at the different marinas is higher at the end of spring and in

  1. Molecular cloning and xenobiotic induction of seven novel cytochrome P450 monooxygenases in Aedes albopictus.

    Science.gov (United States)

    Chan, Hiang Hao; Wajidi, Mustafa Fadzil Farid; Zairi, Jaal

    2014-01-01

    Cytochrome P450 monooxygenase (P450) is a superfamily of enzymes that is important in metabolism of endogenous and exogenous compounds. In insects, these enzymes confer resistance to insecticides through its metabolic activities. Members of P450 from family 6 in insects are known to play a role in such function. In this study, we have isolated seven novel family 6 P450 from Aedes albopictus (Skuse) (Diptera: Culicidae), a vector of dengue and chikungunya fever. Induction profile of these seven genes was studied using several insecticides and xenobiotics. It was found that deltamethrin and permethrin did not induce expression of any genes. Another insecticide, temephos, inhibited expression of CYP6P15 for fivefold and twofold for CYP6N29, CYP6Y7, and CYP6Z18. In addition, copper II sulfate induced expression of CYP6M17 and CYP6N28 for up to sixfold. Benzothiazole (BZT), a tire leachate induced the expression of CYP6M17 by fourfold, CYP6N28 by sevenfold, but inhibited the expression of CYP6P15 for threefold and CYP6Y7 for twofold. Meanwhile, piperonyl butoxide (PBO) induced the expression CYP6N28 (twofold), while it inhibited the expression of CYP6P15 (fivefold) and CYP6Y7 (twofold). Remarkably, all seven genes were induced two- to eightfold by acetone in larval stage, but not adult stage. Expression of CYP6N28 was twofold higher, while expression of CYP6P15 was 15-fold lower in adult than larva. The other five P450s were not differentially expressed between the larvae and adult. This finding showed that acetone can be a good inducer of P450 in Ae. albopictus. On the other hand, temephos can act as good suppressor of P450, which may affect its own bioefficacy because it needs to be bioactivated by P450. To the best of our knowledge, this is the first report on acetone-inducible P450 in insects. Further study is needed to characterize the mechanisms involved in acetone induction in P450. PMID:25399430

  2. Avaliação do bis(4-metilfenilditiocarbimatozincato(II de tetrabutilamônio como acelerador no processo de vulcanização do elastômero polibutadieno Evaluation of [tetrabutyl ammonium bis(4-methylphenyldithiocarbimatezincate-2] as accelerator in vulcanization process of polybutadiene elastomer

    Directory of Open Access Journals (Sweden)

    Leonardo F. V. dos Santos

    2011-01-01

    Full Text Available O ZNIBU, acelerador de caráter lento foi avaliado neste trabalho em composições de polibutadieno. Este acelerador foi sintetizado com o objetivo de substituir, ou reduzir, o uso de alguns aceleradores comerciais muito utilizados em composições elastoméricas mas que, por serem formadores de nitrosaminas, podem ser prejudiciais à saúde. A fim de corrigir o caráter de acelerador lento do ZNIBU, este composto foi utilizado em conjunto com o acelerador comercial CBS (N-ciclohexil-2-benzotiazol-2-sulfenamida. Foi observado que pequenas quantidades dos dois aceleradores não são efetivas na aceleração da vulcanização nas composições do tipo goma pura. No entanto a presença de negro de fumo exerce um efeito positivo sobre a velocidade. As propriedades mecânicas estudadas mostram que o ZNIBU aumenta a resistência à tração da goma pura (35%, em comparação com a composição similar vulcanizada com CBS e, na presença do negro de fumo, este aumento é ainda mais expressivo (175%. Quanto à resistência ao rasgamento, a vulcanização com o ZNIBU forneceu o mais baixo valor da propriedade para a goma pura, enquanto que a composição com negro de fumo apresentou o mais alto valor.ZNIBU, a slow accelerator, was evaluated in polybutadiene compositions. This accelerator was synthesized intending to replace or reduce the use of some very used commercial accelerators in rubber compositions which, due to their nitrosamine-forming potential, can be harmful to health. In order to correct for the slow accelerating character ZNIBU was used in combination with the commercial accelerator CBS (N-cyclohexyl-2-benzothiazole-2-sulfenamide. It was observed that small amounts of the accelerators are not effective in the vulcanization accelerating process of gum type compositions. Nevertheless, the presence of carbon black exerts a positive effect on the reaction rate. The investigated mechanical properties show that ZNIBU improves stress strength of

  3. Isolation and characterization of new p-Terphenyls with antifungal, antibacterial, and antioxidant activities from halophilic actinomycete Nocardiopsis gilva YIM 90087.

    Science.gov (United States)

    Tian, Shou-Zheng; Pu, Xiang; Luo, Guoyong; Zhao, Li-Xing; Xu, Li-Hua; Li, Wen-Jun; Luo, Yinggang

    2013-03-27

    A new p-terphenyl 1 and a novel p-terphenyl derivative 3 bearing a benzothiazole moiety were isolated from halophilic actinomycete Nocardiopsis gilva YIM 90087, along with known p-terphenyl 2, antibiotic novobiocin 4, cyclodipeptides 5-13, and aromatic acids 14 and 15. Their structures were elucidated on the basis of the interpretation of spectral data and by comparison of the corresponding data with those reported previously. The p-terphenyl 1 showed antifungal activity against the three pathogenic fungi, including Fusarium avenaceum, Fusarium graminearum, and Fusarium culmorum, that caused Fusarium head blight with minimal inhibitory concentrations (MICs) of 8, 16, and 128 μg/mL, respectively. Compound 1 showed antifungal activity against Candida albicans with a MIC of 32 μg/mL and antibacterial activity against Bacillus subtilis with a MIC of 64 μg/mL. Novobiocin 4 showed antifungal activity against Pyricularia oryzae with a MIC of 16 μg/mL and antibacterial activity against B. subtilis with a MIC of 16 μg/mL and Staphylococcus aureus with a MIC of 64 μg/mL. The 1,1-diphenyl-2-picryl-hydrazyl assay suggested that 1, 3, and 4 exhibited 54.9% (2 mg/mL), 14.3% (4 mg/mL), and 47.7% (2 mg/mL) free radical scavenging activity, respectively. The positively charged 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical (ABTS(+•)) scavenging assay indicated that 1, 3, 4, and 8 exhibited 68.6% (1 mg/mL), 28.4% (2 mg/mL), 78.2% (0.5 mg/mL), and 54.6% (2 mg/mL) ABTS(+•) scavenging capacity, respectively. The superoxide anion radical scavenging assay suggested that 4 exhibited 77.9% superoxide anion radical scavenging capacity at 2 mg/mL. N. gilva YIM 90087 is a new resource for novobiocin 4. PMID:23441911

  4. Screening and biological characteristics studies of wide wine-making yeasts%葡萄酒野生酿酒酵母的筛选及其生物特性的研究

    Institute of Scientific and Technical Information of China (English)

    汤晓宏; 胡文效; 魏彦锋; 蒋锡龙; 张晶莹; 董兴全; 李敬龙; 邵学东

    2014-01-01

    200 yeast strains were isolated from chardonnay grape skin and vineyard soil of Chateau junding in Penglai Wine Region. 11 yeast strains with excellent performance for wine were selected, one of them (PJ16) was identified as Saccharomyces cerevisiae, respectively based on the analysis of 26SrDNA D1/D2 sequence combination with morpho-logical observation and biochemical and physiological characteristics. Through detection of tolerance and fermentation test, the results showed that the strain PJ16 is suited for brewing grape wine. And the concentrations of its aroma com-ponents produced by the strain PJ16, including hexyl alcohol, 1-nonyl alcohol, 2-nonyl alcohol, nonyl aldehyde, ben-zaldehyde, ethyl acetate, isoamyl acetate, isoamyl acid ethyl ester, ethyl lactate, acetophenone, benzothiazole and 2-a-cetyl furan, 2-methyl tetrahydrothiophene-3-ketone and beta turkic ketone, were much higher than those of the control group, suggesting that the strain PJ16 had excellent characteristics for wine-making.%从蓬莱葡萄酒产区君顶酒庄霞多丽葡萄果实表皮和葡萄园土壤中分离纯化得到200个单菌落,经初筛和复筛,获得性能较好的菌株11株,对其进行26SrDNA D1/D2区序列分析、形态学观察和生理生化测定,将编号为PJ16的菌株鉴定为酵母属酿酒酵母种( Saccharomyces cerevisiae)。通过耐受性及发酵性能测试,表明菌株PJ16适合用于酿造葡萄酒。所酿葡萄酒的香气成分,如正己醇、1-壬醇、2-壬醇、壬醛、苯甲醛、乙酸乙酯、乙酸异戊酯、异戊酸乙酯、乳酸乙酯、乙酰苯、苯并噻唑、2-乙酰基呋喃、2-甲基四氢噻吩-3-酮和β-突厥酮,浓度远高于对照组商品酵母所酿葡萄酒,体现出酿酒酵母PJ16的优良特性。

  5. Dynamic Solvent Control of a Reaction in Ionic Deep Eutectic Solvents: Time-Resolved Fluorescence Measurements of Reactive and Nonreactive Dynamics in (Choline Chloride + Urea) Melts.

    Science.gov (United States)

    Das, Anuradha; Biswas, Ranjit

    2015-08-01

    Dynamic fluorescence anisotropy and Stokes shift measurements of [f choline chloride + (1 - f) urea)] deep eutectic solvents at f = 0.33 and 0.40 have been carried out using a dipolar solute, coumarin 153 (C153), in the temperature range 298 ≤ T ≤ 333 K. Subsequently, measured time-dependent solvent response is utilized to investigate the dynamic solvent control on the measured rates of photoexcited intramolecular charge transfer (ICT) reactions of two molecules, 4-(1-azetidinyl)benzonitrile (P4C) and 4-(1-pyrrolidinyl)benzonitrile (P5C), occurring in these media. Measured average reaction time scales (⟨τ(rxn)⟩) exhibit the following dependence on average solvation times scales (⟨τ(s)⟩): ⟨τ(rxn)⟩ ∝ ⟨τ(s)⟩(α) with α = 0.5 and 0.35 for P4C and P5C, respectively. Such a strong dynamic solvent control of ⟨τ(rxn)⟩, particularly for P4C, is different from earlier observations with these ICT molecules in conventional molecular solvents. Excitation wavelength-dependent fluorescence emissions of C153 and trans-2-[4-(dimethylamino)styryl]-benzothiazole (DMASBT), which differ widely in average fluorescence lifetimes (⟨τ(life)⟩), suggest the presence of substantial spatial heterogeneity in these systems. Dynamic heterogeneity is reflected via the following fractional viscosity (η) dependences of ⟨τ(s)⟩ and ⟨τ(r)⟩ (⟨τ(r)⟩ being solute's average rotation time): ⟨τx⟩ ∝ (η/T)(p) with 0.7 ≤ p ≤ 0.9. Different correlations between ⟨τ(s)⟩ and ⟨τ(r)⟩ emerge at different temperature regimes, indicating variable frictional coupling at low and high temperatures. Estimated dynamic Stokes shifts in these media vary between ∼1200 and ∼1600 cm(-1), more than 50% of which possess a time scale much faster than the temporal resolution (∼75 ps) employed in these measurements. Estimated activation energy for η is closer to that for ⟨τ(r)⟩ than that for ⟨τ(s)⟩, suggesting ⟨τ(s)⟩ being more decoupled

  6. Fate of two herbicides in zero-tension lysimeters and in field soil.

    Science.gov (United States)

    Kasteel, R; Pütz, T; Vanderborght, J; Vereecken, H

    2010-01-01

    In Germany, zero-tension lysimeters are used as part of the registration requirements in case pesticides pose a potential threat to contaminate the groundwater. However, the water regime and the method of pesticide sampling differ between the lysimeters and the field. We monitored the transport of the two herbicides ethidimuron [1-(5- ethylsulfonyl-1,3,4-thiadiazol-2-yl)-1,3-dimethylurea] (ETD) and methabenzthiazuron [1-benzothiazol-2-yl-1,3-dimethyl-urea] (MBT) and their main metabolite, accompanied with bromide as conservative tracer, in zero-tension lysimeters filled with undisturbed soil and in the field. The herbicides were applied as a short pulse to the bare soil surface. Herbicide concentrations were analyzed in the drainage water of the 1.2-m-deep lysimeters and from soil cores taken from the field during six campaigns. Soil coring in the field emphasized matrix flow and allowed us to estimate the field-based dissipation and sorption parameters. Based on mass recovery calculations, the field fate half-life was 870 d for ETD compared with 389 d for its main metabolite. The initially fast field-based dissipation of MBT with a half-life value of approximately 1 mo was followed by a much slower dissipation. The retardation factor was estimated from the concentration profiles by inversely solving the convection-dispersion equation and yielded 18.2 +/- 1.3 for ETD and 36.9 +/- 17.5 for MBT. For the lysimeters, a leaching period of 2 1/2 yr was too short to monitor bulk herbicide mass through the soil matrix. Only 1.7% of the applied EDT and 1.4% of the applied MBT were sampled in the drainage water at 1.2 m depth. Despite contrasting sorption and dissipation properties, both herbicides appeared fast and at the same time in the drainage water, hinting at preferential flow phenomena. Compared with field fate of herbicides measured by soil coring, zero-potential lysimeters emphasize the transport of small amounts of herbicides triggered by preferential flow events

  7. Identification of key amino acid residues modulating intracellular and in vitro microcin E492 amyloid formation

    Directory of Open Access Journals (Sweden)

    Paulina eAguilera

    2016-01-01

    Full Text Available Microcin E492 (MccE492 is a pore-forming bacteriocin produced and exported by Klebsiella pneumoniae RYC492. Besides its antibacterial activity, excreted MccE492 can form amyloid fibrils in vivo as well as in vitro. It has been proposed that bacterial amyloids can be functional playing a biological role, and in the particular case of MccE492 it would control the antibacterial activity. MccE492 amyloid fibril’s morphology and formation kinetics in vitro have been well characterized, however it is not known which amino acid residues determine its amyloidogenic propensity, nor if it forms intracellular amyloid inclusions as has been reported for other bacterial amyloids. In this work we found the conditions in which MccE492 forms intracellular amyloids in E. coli cells, that were visualized as round-shaped inclusion bodies recognized by two amyloidophillic probes, 2-4´-methylaminophenyl benzothiazole and thioflavin-S. We used this property to perform a flow cytometry-based assay to evaluate the aggregation propensity of MccE492 mutants, that were designed using an in silico prediction of putative aggregation hotspots. We established that the predicted amino acid residues 54-63, effectively act as a pro-amyloidogenic stretch. As in the case of other amyloidogenic proteins, this region presented two gatekeeper residues (P57 and P59, which disfavor both intracellular and in vitro MccE492 amyloid formation, preventing an uncontrolled aggregation. Mutants in each of these gatekeeper residues showed faster in vitro aggregation and bactericidal inactivation kinetics, and the two mutants were accumulated as dense amyloid inclusions in more than 80% of E. coli cells expressing these variants. In contrast, the MccE492 mutant lacking residues 54-63 showed a significantly lower intracellular aggregation propensity and slower in vitro polymerization kinetics. Electron microscopy analysis of the amyloids formed in vitro by these mutants revealed that, although

  8. Design, selection, and characterization of thioflavin-based intercalation compounds with metal chelating properties for application in Alzheimer's disease.

    Science.gov (United States)

    Rodríguez-Rodríguez, Cristina; Sánchez de Groot, Natalia; Rimola, Albert; Alvarez-Larena, Angel; Lloveras, Vega; Vidal-Gancedo, José; Ventura, Salvador; Vendrell, Josep; Sodupe, Mariona; González-Duarte, Pilar

    2009-02-01

    Metal chelation is considered a rational therapeutic approach for interdicting Alzheimer's amyloid pathogenesis. At present, enhancing the targeting and efficacy of metal-ion chelating agents through ligand design is a main strategy in the development of the next generation of metal chelators. Inspired by the traditional dye Thioflavin-T, we have designed new multifunctional molecules that contain both amyloid binding and metal chelating properties. In silico techniques have enabled us to identify commercial compounds that enclose the designed molecular framework (M1), include potential antioxidant properties, facilitate the formation of iodine-labeled derivatives, and can be permeable through the blood-brain barrier. Iodination reactions of the selected compounds, 2-(2-hydroxyphenyl)benzoxazole (HBX), 2-(2-hydroxyphenyl)benzothiazole (HBT), and 2-(2-aminophenyl)-1H-benzimidazole (BM), have led to the corresponding iodinated derivatives HBXI, HBTI, and BMI, which have been characterized by X-ray diffraction. The chelating properties of the latter compounds toward Cu(II) and Zn(II) have been examined in the solid phase and in solution. The acidity constants of HBXI, HBTI, and BMI and the formation constants of the corresponding ML and ML2 complexes [M = Cu(II), Zn(II)] have been determined by UV-vis pH titrations. The calculated values for the overall formation constants for the ML2 complexes indicate the suitability of the HBXI, HBTI, and BMI ligands for sequestering Cu(II) and Zn(II) metal ions present in freshly prepared solutions of beta-amyloid (Abeta) peptide. This was confirmed by Abeta aggregation studies showing that these compounds are able to arrest the metal-promoted increase in amyloid fibril buildup. The fluorescence features of HBX, HBT, BM, and the corresponding iodinated derivatives, together with fluorescence microscopy studies on two types of pregrown fibrils, have shown that HBX and HBT compounds could behave as potential markers for the presence

  9. 以芳香烃受体为药物靶点的肿瘤治疗研究%Anti-tumor therapy for targeting aryl hydrocarbon receptor

    Institute of Scientific and Technical Information of China (English)

    刘颖; 张洪英; 唐涛; 刘飞飞; 吴谓; 罗瑛; 张继虹

    2016-01-01

    Aryl hydrocarbon receptor ( AhR) is a ligand-depend-ent transcription factor that mediates the toxicity of xenobiotic ligands like 2,3,7,8-tetrachlorodibenzo-p-dioxins(TCDDs). AhR influences tumor growth, survival, migration and invasion by regulating proliferation, apoptosis and immune metabolism of tumor cells. AhR has two ways to regulate tumor development, and ligands like polycyclic aromatic hydrocarbons( PAHs) , hal-ogenated aromatic hydrocarbons( HAHs) can induce tumorigene-sis. However, some compounds such as benzothiazole and amin-oflavone can activate AhR, which suppresses the tumor progres-sion and suggests that AhR may be a novel drug target for anti-tumor therapy. The paper discussed the role of AhR in tumori-genesis, the mechanism of the drugs targetting AhR and the sta-tus of studying AhR as a potential target in anticancer therapy.%芳香烃受体( aryl hydrocarbon receptor,AhR)是一种配体依赖性转录因子,可调控如2,3,7,8-四氯代苯并二恶英(2,3,7,8-tetrachlorodibenzo-p-dioxins,TCDDs)等外源性配体化合物的毒性作用。通过参与细胞增殖与凋亡、免疫代谢等过程,AhR影响肿瘤的生长、存活、迁移和侵袭。 AhR对肿瘤的调控具有双重作用,在多环芳烃、卤代芳烃等配体作用下, AhR可促进肿瘤生成;但苯并噻唑、氨基黄酮等化合物激活AhR后,可发挥抑癌功能,有望成为治疗肿瘤的药物靶点。该文主要讨论AhR在肿瘤中的作用、以AhR为靶点的药物作用机制以及目前AhR靶向药物的研究现状。

  10. Toxicity Assessment of Five Chemicals on Eremias argus and Coturnix japonica%5种化学品对丽斑麻蜥和日本鹌鹑的毒性研究

    Institute of Scientific and Technical Information of China (English)

    常静; 杨淞霖; 戴欣; 李济彤; 王会利; 瞿唯钢

    2015-01-01

    Toxicity effects of chemicals have rarely been evaluated in reptiles. In this study, the acute toxicity test method of native reptile-Eremiasarguswas established in order to evaluate the toxicity of chemicals to reptiles. Er-emias argus were exposed to isocyanate, 1,2-benzisothiazolin-3-one, 2,4-dichlorophenol, benzothiazole and diphe-nylketone respectively in acute oral toxicity test. 7 d-LD50 values of lizard were compared with avian model spe-cies-Coturnix japonica. According to the results, 7 d-LD50 values of isocyanate and benzothiazole to E.argus were 125 mg•kg-1 and 500 mg•kg-1 while to C.japonicathe values were 27 mg•kg-1 and 37 mg•kg-1;7 d-LD50 val-ue of 1,2-benzisothiazolin-3-one, 2,4-dichlorophenol and diphenylketone to E.argus were all greater than 1 000 mg•kg-1 while to C. japonica the values were 909 mg•kg-1 , 787 mg•kg-1 and 528 mg•kg-1 . The results showed that avian could not be used as surrogate species to reflect the chemical toxicity to reptiles exactly. The toxicity of chemicals to reptiles should be paid more attention. Using native lizard as model animal for reptile ecotoxicology studies will benefit the protection of native reptile species and maintain the ecological balance.%目前,在化学品生态风险评价体系中对爬行动物的毒性效应研究较少。本研究参考鸟类急性经口毒性试验建立了我国本土爬行动物———丽斑麻蜥(Eremias argus)的急性毒性测试方法,来评价化学品对爬行动物和鸟类的毒性效应之间的差异。选择异氰酸酯、1,2-苯并异噻唑-3-酮、2,4-二氯苯酚、苯并噻唑和二苯甲酮5种化学品分别对丽斑麻蜥进行暴露实验,并与鸟类模式物种———日本鹌鹑(Coturnix japonica)的急性毒性结果进行比较。结果发现异氰酸酯和苯并噻唑对丽斑麻蜥7 d的半数致死剂量(7 d-LD50)分别为125 mg•kg-1和500 mg•kg-1,而对日本鹌鹑的7 d-LD50值分别为27 mg•kg-1和37 mg•kg-1;1,2-

  11. Alternativas de control en la pudrición radical de cebolla para el Valle de la Trinidad, Baja California Control Alternatives for Onion root rot in the Trinity Valley, Baja California

    Directory of Open Access Journals (Sweden)

    Armando Pulido-Herrera

    2012-02-01

    solarization (SPT; 6 black plastic solarization (SPN; 7 SPT + EB; 8 SPT + CR; 9 SPN + EB; 10 SPN + SO; 11 Trichodef (Trichoderma harzianum; and 12 control. In Experiment II (2008, treatments were the same except treatment 2, replaced by a protective agent (plant extracts, and in experiment III (2009 the treatments were: 1 SPT + sheep manure (EO; 2 SPN + EO; 3 SPT; 4 SPN; 5 biological control (Trichoderma spp.; and 6 chemical control (2 - (thiocyanomethylthio benzothiazole 30%. the results indicated that the clear plastic solarization treatments with or without organic amendments showed significant increases (p<0.05 from 22 to 34%yield and diameterwith respect to biological and chemical control, but the latter two treatments in the incidence and severity decreasedsignificantly (p<0.05 , so that the clearplastic solarization and biological control, are viable alternatives to control root rot in onion crops in Baja California, Mexico.

  12. Molecular Dynamics Study on the Inhibition Mechanisms of Drugs CQ1-3 for Alzheimer Amyloid-β40 Aggregation Induced by Cu(2.).

    Science.gov (United States)

    Dong, Mingyan; Li, Haoyue; Hu, Dingkun; Zhao, Wei; Zhu, Xueying; Ai, Hongqi

    2016-05-18

    H-bond with Asp23 would be another key factor to be taken seriously into account in drug screens. Meanwhile, the structural characteristics of drug CQi itself are also worthy of attention. First, the increasing polarity from CQ1 and CQ2 to CQ3 in turn results in increasing probability and strength of the interaction between the drug and the N-terminal (NT) region of Aβ40, which obviously inhibits Aβ peptide aggregation induced by Cu(2+) binding. Second, both the benzothiazole ring and phenol ring of CQi can overcome the activation energy barrier (∼16 kJ/mol) to rotate flexibly around the intramolecular C7-N14 bond to achieve the maximum match and interaction with the ambient Aβ40 residues. Such a structural feature of CQi paves the new way for ones in selection and modification of a drug. PMID:26871000

  13. 苏云金芽胞杆菌挥发性物质的测定%Determination of Bacillus thuringiensis volatile substances

    Institute of Scientific and Technical Information of China (English)

    郑梅霞; 潘志针; 刘波; 陈峥; 车建美; 唐建阳; 朱育菁; 陈梅春

    2014-01-01

    , tetradecane, eicosane, 2-(methylthio)-Benzothiazole. Conclusion The method of HS-SPME/GC-MS is effective, practical, easy for operation, and suitable for the analysis of the vo-latile substances of Bacillus thuringiensis, so as to provide theoretical basis for food safety assessment.

  14. The Fluorescent Staining of Mollusks Haemocytes with Thioflavin T%贝类血细胞硫代黄素T荧光染色方法

    Institute of Scientific and Technical Information of China (English)

    王宜艳; 宋晓娜; 付静芸; 孙虎山

    2011-01-01

    Thioflavin (TFT) , a benzothiazole fluorescent dye, is able to selectively stain amyloid structures and is mainly used to detect amyloidosis using fluorescence microscopy. In this study, the circulating hemocytes of four species of mollusks, Chlamys farreri ( Bivalvia) , Mactra chinensis ( Bivalvia) , Natica janthostomoides (Gastropoda) and Octopus variabilis (Cephalopoda), were observed in order to develop the fluorescence staining method of mollusks haemocytes with TFT. Under fluorescence microscope, haemocytes of four mollusks showed yellow-green fluorescence after treatment with 0. 1% TFT. The outlines of the cells were clear; the nuclei and granules in the cytoplasm were clearly distinguishable. The haemocytes of all four mollusks could be divided into two types, granulocytes and agranulocytes, based on whether cytoplasmic granules could be observed. In scallop, clam and octopus, the agranulocytes could be subdivided into hyalinocytes and haemoblasts, while the granulocytes could be subdivided into small granulocytes and large granulocytes according to the size of granules in the cytoplasm. The fluorescence staining method of mollusks haemocytes with TFT is easy to operate, and the samples can be observed for a long time after staining because the fluorescence is not easy to bleach. This study is the first to use TFT in the morphological characterization and classification of mollusks haemocytes, and suggests that TFT fluorescence staining is a good method for the observation and classification of mollusks haemocytes.%硫代黄素T( thioflavin T,TFT)是一种用于组织学的苯并噻唑荧光染料,因其对淀粉样蛋白有高亲和性而主要被用于淀粉样病变的荧光显微检测.本研究分别以软体动物门双壳纲的栉孔扇贝(Chlamys farreri)和中国蛤蜊(Mactra chinensis)、腹足纲的拟紫口玉螺(Natica janthostomoides)及头足纲的短蛸(Octopus variabilis)4种软体动物为实验材料,对贝类血细胞

  15. Technetium radiopharmaceuticals, current situation and perspectives

    International Nuclear Information System (INIS)

    search for 99mTc-radiopharmaceuticals also lead to the development of several ligand systems for the formation of stable 99mTc-complexes, such as Tc(V)O and Tc(V)dioxo complexes with a wide variety of tetraligands and diligands, Tc(V)nitrido complexes, Tc(I)- hexa-isonitriles, complexes of Tc with hydrazinonicotinic acid (Hynic), and most recently, the promising Tc(I)(CO)3 complexes with numerous triligands. This knowledge has been exploited for the design of conjugates of a Tc-binding ligand with biomolecules (proteins, peptides, drugs binding to receptors, transporter proteins, enzymes, RNA) in order to allow labelling of the bioactive compounds with 99mTc and use of the radiolabelled agents for diagnosis and follow-up of specific diseases, especially cancers. As derivatization with a 99mTc-chelate increases the molecular weight with at least 300 Da, it mostly seriously alters the biological properties of small compounds, rendering the radiolabeled biomolecule useless for the intended purpose (e.g. 99mTc complexes of conjugates of glucose, flumazenil, benzylguanidine, benzothiazoles, ...). This constitutes a major challenge to the successful development of small 99mTc labelled receptor agents. The only positive example in this series is 99mTc-TRODAT-1, based on a conjugate of a BAT tetraligand and a tropane, with preserved (although reduced) affinity for the dopamine transporter. However, in the case of relatively large biomolecules such as peptides and proteins, derivatization with a 99mTc-chelate is relatively well tolerated without compromising too much the affinity and specificity for the target structure. Examples of clinically useful radiopharmaceuticals designed in this way are 99mTc-Hynic-tricine-annexin for imaging of apoptosis, 99mTc-EDDA/HYNIC-Tyr(3)-octreotide and 99mTc-N4-[Tyr3]octreotate for visualisation of neuroendocrine gastro-entero-pancreatic tumours, complexes with peptides in which a sequence is incorporated to provide a donor atom set which allows

  16. Influence of alternating soil drying and wetting on the desorption and distribution of aged 14C-labeled pesticide residues in soil organic fractions

    Science.gov (United States)

    Jablonowski, N. D.; Mucha, M.; Thiele, B.; Hofmann, D.; Burauel, P.

    2012-04-01

    initially applied after a total of 10 water extractions, respectively. MBT was detected but not quantified, whereas its metabolite MABT (2-methylamino-benzothiazole) was detected (0.8 vs 0.3 μg kg-1, in dry/wet vs wet/wet soil water extracts, respectively) after 10 water extractions. These results demonstrate the long-term persistence of ETD and MBT and metabolites and their remobilization potential facilitated by soil drying and rewetting. For all samples, the DOC content was significantly higher for the water extracts obtained after dry/wet cycles compared to values obtained from the constantly moistened soil samples. The DOC and water extracted residual 14C activity correlated positively. This result indicates that pesticide residues are associated with DOC which might function as a shuttle for the distribution of pesticide residues. This molecular association can be released into solution where it might be degraded co-metabolically. Overall, the results suggest that intermittent soil drying and rewetting alters the disaggregation of soil aggregates, resulting in a release of entrapped organic carbon and pesticide molecules. Furthermore, analysis of the organic fractions obtained from the 14C pesticide residues containing soil revealed that 14C residues were mainly associated with the humin fraction. The analysis of the organic fractions revealed that extractable residual 14C activity of ETD was more associated with the fulvic acid fraction compared to the residual pesticide 14C activity of MBT, being more associated with the humic acid fraction. For 14C MBT residues, the distribution of the 14C residues in the organic fractions remained rather equal throughout the water extraction cycles. This observation can be supported by the non-mobile character of MBT in soil and its higher KOC value of 247-587 compared to the rather mobile pesticide ETD with a KOC value of 37.1-149. However, for both pesticides a decrease of residual 14C activity in the humic and fulvic acid

  17. Assessment of Hyporheic Zone, Flood-Plain, Soil-Gas, Soil, and Surface-Water Contamination at the McCoys Creek Chemical Training Area, Fort Gordon, Georgia, 2009-2010

    Science.gov (United States)

    Guimaraes, Wladmir B.; Falls, W. Fred; Caldwell, Andral W.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

    2011-01-01

    censored and, therefore, only 7 of the 71 samplers were reported as detecting TPH. In addition, benzene, toluene, ethylbenzene, and total xylene were detected above the method detection level in 22 samplers. Other compounds detected above the method detection level included naphthalene, octane, undecane, tridecane, 1,2,4-trimethylbenzene, trichloroethylene, perchloroethylene, chloroform, and 1,4-dichlorobenzene. Subsequent to the soil-gas survey, five locations with elevated contaminant mass were selected and a passive sampler was deployed at those locations to detect the presence of organic compounds classified as explosives or chemical agents. No explosives or chemical agents were detected above the method detection level, but some compounds were detected below the method detection level but above the nondetection level. Dimethyl disulfide, benzothiazole, chloroacetophenones, and para-chlorophenyl methyl sulfide were all detected below the method detection level but above the nondetection level. The compounds 2,4-dinitrotoluene, and para-chlorophenyl methyl sulfone were detected in samplers but also were detected in trip blanks and are not considered as present in the MCTA. The same five locations that were selected for sampling of explosives and chemical agents were selected for soil sampling. Metal concentrations in composite soil samples collected at five locations from land surface to a depth of 6 inches did not exceed the U.S. Environmental Protection Agency Regional Screening Levels for Industrial Soil. Concentrations in some compounds were higher than the South Carolina Department of Health and Environmental Control background levels for nearby South Carolina, including aluminum, arsenic, barium, beryllium, chromium, copper, iron, lead, manganese, nickel, and potassium. A surface-water sample was collected from McCoys Creek and analyzed for volatile organic compounds, semivolatile organic compounds, and inorganic compounds (metals). No volatile organic compounds

  18. 西湖龙井茶香气成分的全二维气相色谱-飞行时间质谱分析%Analysis of Aroma Components in Xihu Longjing Tea by Comprehensive Two-Dimensional Gas Chromatography- Time-of-Flight Mass Spectrometry

    Institute of Scientific and Technical Information of China (English)

    朱荫; 吕海鹏; 林智; 杨停; 施江; 余方林; 戴伟东; 谭俊峰; 郭丽; 张悦; 彭群华

    2015-01-01

    , hentriacontane, acetaldehyde, pentanal, hexanal, furfural, heptanal, phenylacetaldehyde, nonanal, 1-ethoxypropane, 2-ethoxybutane, 1-ethoxybutane, 1,1-diethoxyethane, 1-ethoxypentane, pentanol, tert-butanol, benzyl alcohol, phenethyl alcohol, phytol, diisobutyl phthalate, dibutyl phthalate, ethyl 2-(5-methyl-5-vinyltetrahydrofuran-2-yl) propan-2-yl carbonate, (Z)-hex-3-en-1-yl hexanoate, methyl palmitate, acetoin, 2,4-di-tert-butylphenol, 3-methylbutanoic acid, nonanoic acid, hexadecanoic acid, linoleic acid, octadecanoic acid, dimethyl sulfoxide, benzothiazole, indole, caffeine, linalool oxide (pyranoid), 2,3-dihydrobenzofuran, ethylbenzene, phenylpropane, and 1-methylnaphthalene, were found to be relatively high contents in aroma components of Xihu Longjing tea, suggesting that they played an important role in effecting the aroma quality of Xihu Longjing tea. The analysis of characteristic aroma compositions indicated that enols, aldehydes, alcohols, esters and aromatic hydrocarbons with agreeable smell would be responsible for the outstanding aroma quality of Xihu Longjing tea, and the effects of alkanes, ethers, organic acids and sulphur compounds with no special smell or offensive odor and aroma compounds with low odor threshold values were also worth future research.[Conclusion] The successful application of GC×GC-TOFMS technology in tea aroma analysis has improved the number of identified compounds significantly, which could make up for the defects of GC-MS analysis to some extent and supply the advanced technical support for the future in-depth studies on the chemical composition of tea aroma and formation mechanism of tea aroma quality.%【目的】香气是评价茶叶品质优劣的最重要因子之一,探明茶叶香气的化学组成可进一步丰富茶叶香气化学理论,为改善和提高茶叶香气品质提供重要的科学理论依据。【方法】采用全二维气相色谱-飞行时间质谱联用技术(GC×GC-TOFMS)与气相色谱-质谱联