Synthesis of Nucleoside 5′-H-Phosphonothioates via Nucleoside 5′-Phosphinate Intermediates

Abstract

A general method for the synthesis of nucleoside 5′-H-phosphonothioates are described in this paper. The synthetic strategy involves the coupling of 2′,3′-O-isopropylidene-protected nucleosides with triethylammonium phosphinate in the presence of pivaloyl chloride, oxidation with elemental sulfur, and final deprotection of 2′,3′-O-isopropylidene group with 50% aqueous solution of trifluoroacetic acid.