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91.
92.
A systematic study of glycopeptide esterification for the semi‐quantitative determination of sialylation in antibodies
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93.
Hydrosilylation is an important process, not only in the silicon industry to produce silicon polymers, but also in fine chemistry. In this review, the development of rhenium-based catalysts for the hydrosilylation of unsaturated bonds in carbonyl-, cyano-, nitro-, carboxylic acid derivatives and alkenes is summarized. Mechanisms of rhenium-catalyzed hydrosilylation are discussed. 相似文献
94.
95.
Jean-Marie Catel Yves Mollier 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2)
Abstract The 3-methylthio-1. 2-dithiolylium including at 5 position a donor substituent, in acetic acid in the presence of pyridine, the 2-methylthio-1. 3-dithiolylium ions in methylene chloride-triethylamine, react with the 2-butene nitrile derivatives and lead to the (A) and (B) corresponding 4-dithiolylidene-2-butene nitriles. In contrast ring opening reaction of the 1, 2-dithiole is observed when 2-cyano-3-phenyl-2-butene nitrile reacts with the 3-methylthio-4-aryl-1. 2-dithiolylium ions in 3 and 5 positions, in methylene chloride-triethylamine. The nucleophilic attack on the 5 position of the dithiolylium ion leads to a 2-cyano-3-phenyl-3 (4-aryl-5-methylthio-2-thienyl) propene nitrile (C), meanwhile the attack on the 3 position leads to a 2-cyano-3-phenyl-3-(4-aryl-3-mercapto-2-thienyl) propene nitrile (D). The proposed structures are established by means of physical methods (IR, NMR, and Mass Spectrometry) and by non ambiguous synthesis. The reactivities of the various sites are explained in function of the electronic and steric effects, furthermore the reaction conditions and the intermediary isolation allow to propose the mecanisms of these reactions. 相似文献
96.
The successive steps of the computer analysis of a NMR spectrum are examined. Better results can be obtained by direct simulation of tentative model spectra. As an example the 1H-NMR spectrum of amphetamine is analysed. 相似文献
97.
Maud Jenart Claude Niebel Jean-Yves Balandier Julie Leroy Alix Mignolet Sara Stas Antoine Van Vooren Jérôme Cornil Yves Henri Geerts 《Tetrahedron》2012,68(1):349-355
Two quaterthiophene-based dimers including an ethylene bridge have been designed and efficiently prepared; experimental and computational studies show a promising potential as semiconducting material with a charge transport of higher dimensionality compared to quaterthiophene. 相似文献
98.
Isomer separation and effect of the degree of polymerization on the gas‐phase structure of chondroitin sulfate oligosaccharides analyzed by ion mobility and tandem mass spectrometry
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99.
Tarak Saied Nourchaine Jelaiel Mohamed Lotfi Efrit Yves Fort Corinne Comoy 《Tetrahedron》2017,73(11):1489-1494
We report herein a short and efficient synthesis of benz[e][1,2,4]- or [d][1,2,6]oxadiazepines and benzo[f][1,3,5]triazocines from easily prepared N-aryl iminoesters. The strategy involves a bis-nucleophile reagent (hydroxylamine or guanidine) that promotes a one-step ring closure from the starting functionalized iminoesters. 相似文献
100.