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Dr. Debangshu Chaudhuri Dr. Eva Sigmund Annemarie Meyer Lisa Röck Philippe Klemm Sebastian Lautenschlager Agnes Schmid Shane R. Yost Prof. Dr. Troy Van Voorhis Dr. Sebastian Bange Prof. Dr. Sigurd Höger Prof. Dr. John M. Lupton 《Angewandte Chemie (International ed. in English)》2013,52(50):13449-13452
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Christine M. J. Gallampois Emma L. Schymanski Mahmoud Bataineh Sebastian Buchinger Martin Krauss Georg Reifferscheid Werner Brack 《Analytical and bioanalytical chemistry》2013,405(28):9101-9112
Many environmental mutagens, including polyaromatic compounds are present in surface waters, often in complex mixtures and at low concentrations. The present study provides and applies a novel, integrated approach to isolate polyaromatic mutagens in river water using a sample from the River Elbe. The sample was taken downstream of industrial discharges using blue rayon (BR) as a passive sampler that selectively adsorbs polyaromatic compounds and was subjected to effect-directed fractionation in order to characterise the compounds causing the detected effect(s). The procedure relies on three complementary fractionation steps, the Ames fluctuation assay with strains TA98, YG1024 and YG1041 with and without S9 activation and analytical screening. Several mutagenic fractions were isolated by combining mutagenicity testing with fractionation. The enhanced mutagenicity in the nitroreductase and/or O-acetyltransferase overexpressing strains YG1024 and YG1041 strains suggested amino- and/or nitro-compounds causing mutagenicity in several fractions. Analytical screening of mutagenic fractions with LC-HRMS/MS provided a list of molecular formulas typically containing one to ten nitrogen and at least two oxygen atoms supporting the presence of amino and nitro-compounds in the mutagenic fractions. Figure
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LewisX (Lex) antigen based carbohydrate–carbohydrate interactions are mediated by complexation of metal ions. Although theoretical studies about the influence of participating hydroxyl groups in the Lex trisaccharide head group (Galβ(1-4)[Fucα(1-3)]GlcNAc) could gave same rudimental information about the basic mechanism behind this interaction, a little is known about orientation and configuration of the hydroxyl groups required for the specific interaction mediated by Ca2+ complexation. Therefore, there is a need of non-natural derivatives to provide detailed information about the requirements for hydroxyl group arrangement in Lex head group surface plasmon resonance and gold nanoparticle techniques have shown to be powerful tools to investigate carbohydrate–carbohydrate interactions. Benzaldehyde-functionalized glycans can be used for attachment to both gold nanoparticles and surface plasmon resonance sensor surfaces. Therefore, seven benzaldehyde equipped Lex analogs including the natural trisaccharide were synthesized utilizing convergent approach. The derivatives were applied in ongoing carbohydrate–carbohydrate interaction studies by surface plasmon resonance experiments to prove theoretical postulate about the structural requirements of hydroxyl group arrangements in Lex trisaccharides. 相似文献
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Prof. Xuefeng Wang Prof. Lester Andrews Dipl.Chem. Felix Brosi Dr. Sebastian Riedel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(4):1397-1409
The reactions of laser‐ablated Au, Ag, and Cu atoms with F2 in excess argon and neon gave new absorptions in the M? F stretching region of their IR spectra, which were assigned to metal‐fluoride species. For gold, a Ng? AuF bond was identified in mixed neon/argon samples. However, this bonding was much weaker with AgF and CuF. Molecules MF2 and MF3 (M=Au, Ag, Cu) were identified from the isotopic distribution of the Cu and Ag atoms, comparison of the frequencies for three metal fluorides, and theoretical frequency calculations. The AuF5 molecule was characterized by its strongest stretching mode and theoretical frequency calculations. Additional evidence was observed for the formation of the Au2F6 molecule. 相似文献
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