Methyl 2,3-di-O-benzoyl-6-deoxy-a+galactopyranoside (2) was converted into the 4-deoxy4 iodo-a-L-gko derivative 4 by triflate-mediated inversion. Catalytic reduction of 4 gave methyl 2,3-di-Obenzoyl-4,6-dideoxy-a-L-xylo-hexopyranoside (6) and subsequent 0-debenzoylation gave methyl 4,6-dideoxy-a-L-xylo-hexopyranoside (7). Selective benzoylation of L-fucose gave I ,2,3-tri-0-benzoyl-a+fucopyranose (14). An analogous sequence of reactions, based on the inversion of configuration at C-4, yielded 4,6-dideoxy-4-iodo-L-glucopyranose (17) and 4,6-dideoxy+xylo-hexopyranose (19). Reaction of the 4trifluoromethanesulfonate (15) of 14 with sodium fluoride in N,iV-dimethylformamide gave 1,2,3-tri-Obenzoyl-6-deoxy-4-0-formyl-u+glucopyranose (12) and 1,2,3-tri-O-benzoyl-4,6-dideoxy-a+threo-hex4 enopyranose (13). Treatment of 14 with diethylaminosulfur trifluoride and then 0-debenzoylation gave 4,6-dideoxy-4-fluoro+glucopyranose (11). Reaction of 15 with sodium iodide in N,N-dimethylformamide gave 1,2,3-tri-O-benzoyI-4,6-dideoxy-4-iodo-a-L-~ucopyranose (16). The a-glycosyl bromide (20) derived from 16 reacted stereoselectively withdibenzyl phosphate to give the/?-(21) or a-glycosyl dibenzyl phosphate (22).