Abstract
The synthesis of novel acyclic pyrimidine nucleoside analogues with 1,2,3-triazole ring bound via ethylene spacer or directly to C-5 of pyrimidine ring has been reported. 1,4-Disubstituted 1,2,3-triazoles were synthesized by click chemistry approach using regioselective copper(I)-catalyzed 1,3-dipolar cycloaddition reaction between terminal alkyne and azido pyrimidines under both conventional (method A) and microwave (method B) conditions. N-Alkylation of triazolyl pyrimidines afforded 5-[2-(1,2,3- triazolyl)ethyl]pyrimidine derivatives with penciclovir-, ganciclovir-like and 2,3-dihydroxypropyl side chain, as well as 5-(1,2,3- triazolyl)pyrimidine derivatives with penciclovir- and ganciclovir-like side chain. The stereostructures of 2-hydroxyethyl, 2- tosyloxyethyl, 2-azidoethyl and 4-acetoxymethyl-1,2,3-triazolyl C-5 substituted pyrimidine derivatives were unambiguously confirmed by their X-ray crystal structure analysis.
Keywords: Acyclic pyrimidine nucleoside, Azide-alkyne cycloaddition, Click chemistry, 1, 4-disubstituted 1, 2, 3-triazoles, X-ray diffraction, supramolecular assembling.