Fluoronucleosides, isothiocyanato C-nucleosides, and thioureylene di-C-nucleosides via cyclic sulfates

Abstract

Cyclic sulfates of N- and C-nucleosides (D-ribo and D-erythro configurations, respectively) are used to prepare 3′-fluoro and 3′-azido D-Xylo N-nucleosides and L-threo C-nucleosides. The reduction of the 3′-azido C-nucleosides (furan, imidazoline-2-thione, and pyrrole derivatives) gives 3′-amino C-nucleosides, which, by reaction with thiocarbonyldiimidazole, are transformed into 3′-isothiocyanato C-nucleosides. Reaction of the 3′-amino with the 3′-isothiocyanato C-nucleosides gives thioureylene di-C-nucleosides, a type of nucleotide analogue with a nonionic bridge isosteric of the phosphate group.