N-Glycosylation of 2,3-dideoxyfuranose derivatives having a (diethoxyphosphorothioyl)difluoromethyl group at the 3α-position

Lewis acid-mediated N-glycosylation of 2,3-dideoxyribofunanosides having a (diethoxyphosphorothioyl)difluoromethyl group at the 3α-position with silylated nucleobases was examined. The phosphorothioyldifluoromethyl was found to be an effective functional group for the diastereoselective synthesis of β-N1-pyrimidine-nucleotide analogues and . However, the method was not useful for the diastereoselective synthesis of adenine nucleotide analogues. The nucleotide analogue was transformed to the difluoromethylenephosphonate analogue of thymidine-3′-phosphate by oxidation with m-CPBA, followed by aqueous work-up.