Results 1 - 10 of 1887
Results 1 - 10 of 1887. Search took: 0.025 seconds
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[en] The review covers methods for the synthesis of aza(deaza)xanthines, i.e., fused pyrrolo-, pyrazolo- and triazolopyrimidine heterocyclic systems, which are common core structures of various biologically active compounds. The extensive range of modern synthetic approaches is organized according to target structures and starting building blocks. The presented material is intended to benefit broad audience of specialists in the fields of organic, medicinal and pharmaceutical chemistry. The bibliography includes 195 references
[en] Data on key chemical transformations of thiosemicarbazides resulting in heterocyclic compounds are generalized and described systematically. Methods for the synthesis of five- and six-membered heterocycles with two and three heteroatoms are considered. The bibliography includes 190 references.
[en] The published data on the methods of synthesis and chemical transformations of nitrogenous heterocyclic compounds spiro-fused with a cyclopropane fragment are described systematically and generalised. The bibliography includes 146 references.
[en] Syntheses of modified steroids annulated at the 16-, 17-positions with five- and six-membered heterocycles are reviewed. The biological activity profiles of these compounds as important secondary metabolites are described.
[en] The data on the reactivity of sulfur monochloride published in the past 15 years have been reviewed and systematized. The review focuses on the synthesis of acyclic and heterocyclic compounds with the use of S_2Cl_2. The bibliography includes 154 references
[en] The photochemistry of cyclobutanes and saturated four-membered heterocycles with two exocyclic double bonds (except bisalkylidenecyclobutanes) is reviewed. Emphasis is laid on photoproducts rather than on mechanism, with special regard for the formation of (hetero)methylenecyclopropanes via photoextrusion of small stable molecules. (author)
[en] Published data on the methods of synthesis and reactivity of α-acyllactams are described systematically and generalized. The attention is focused on the recent achievements in the synthesis of heterocyclic compounds and biologically active products from α-acyllactams and cyclic imines obtained from α-acyllactams. Bibliography - 168 references.
[en] New heterocyclic compounds with phenyl chromium tricarbonyl substituents were synthesized by the reaction of triammine(tricarbonyl)chromium with phenyl-substituted 1,3-oxazacy-cloalkanes bearing acetyl, tert-butyloxycarbonyl, or phenyl group at the nitrogen atom. The resulting compounds were isolated in the individual state and characterized by physicochemical methods of analysis.