A New Route for Preparation of 2-Deoxy-D-ribofuranose Phospho Sugar

The addition reaction of dimethyl phosphonate to (2R,4S)-4-(tertbutyldimethylsilyl)oxymethyl-2-methyl-1,3-dioxan-5-one (11a), followed by dehydroxylation, provided 1-O-(tert-butyldimethylsilyl)-3-deoxy-3-dimethoxyphosphinoyl-2,4-O-ethylidene-D-erythritol (13a). Elongation of carbon skeleton of the D-erythrose (14) derived from 13a and then acidic methanolysis gave a mixture of methyl 2,4-dideoxy-4-dimethoxyphosphinoyl-alpha,beta-D-erythropentopyranosides (7), which was led to 2-deoxy-D-ribofuranose phospho sugar (4) in an appreciably improved total yield compared with the procedures via previously reported route.