Among the variety of sulfonamides, triflamides (CFSONHR, TfNHR) occupy a special position in organic chemistry. Triflamides are widely used as reagents, efficient catalysts or additives in numerous reactions. The reasons for the widespread use of these compounds are their high NH-acidity, lipophilicity, catalytic activity and specific chemical properties.
View Article and Find Full Text PDFOxidative sulfonamidation of divinylsilanes with various sulfonamides in different solvents is reported. With -BuOI as an oxidant, halogenation is the main process, whereas aziridines are the minor products. With NBS in CHCl the products of bromination or bromosulfonamidation were obtained, whereas in MeCN or THF the Ritter-type solvent interception products are formed.
View Article and Find Full Text PDFThe reaction of trimethyl(vinyl)silane with sulfonamides in the presence of N-bromosuccinimide was shown to proceed regioselectively in methylene chloride under mild conditions and led to the products of bromosulfamidation in up to 88% yield. The obtained adducts undergo base-promoted dehydrobromination to give 2-trimethylsilyl-N-sulfonyl aziridines in a close to quantitative yield. In the reaction with trifluoromethanesulfonamide in acetonitrile or tetrahydrofuran, the Ritter-type (solvent-interception) products were obtained and converted to 1-triflyl-2-methyl-5-(trimethylsilyl)-2-imidazoline or 4-triflyl-3-(trimethylsilyl)-1,4-oxazocane in almost quantitative yield.
View Article and Find Full Text PDFOn the basis of complex approach to bone and haematopoetic tissue interaction the authors studied the influence of low weight metabolites on stromal fibroblasts and components of extacellular matrix of bone and skin (collagen and glycosaminoglycans). Specificity of different metabolites action on physico-chemical abilities of type I collagen, amino acid composition changes, surface charge, ratio of alpha- and beta-compounds, BrCN-fragments of alpha-1 component cross-links was shown. The dose dependence of formiate effect on processes of proteins glycosilation, cross-linking in bone and cartilage connective tissue and serum glycoproteins was established.
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