Transglycosylation reactions of permethylated methyl d-glucopyranosides with partially methylated 1,5-anhydroalditols

Transglycosylation of methyl 2,3,4,6-tetra-O-methyl-α- and β-d-glucopyranosides with 1,5-anhydro-2,3,6-tri-O-methyl-d-glucitol and 1,5-anhydro-2,3,4-tri-O-methyl-d-glucitol took place in the presence of trimethylsilyl trifluoromethanesulfonate or boron trifluoride etherate, resulting in the formation of disaccharide derivatives. A disaccharide which could have been formed by the transglycosylation reaction of the intermediates was observed during the reductive-cleavage reaction of permethylated pullulan.