Selective esterification of methyl α-d-glucopyranoside

Abstract 6-Monoesters of methyl α- D -glucopyranoside have been prepared by transesterification with methyl laurate, methyl palmitate, methyl stearate, and methyl benzoate, catalyzed by sodium methoxide in the absence of a solvent. The benzoylation of methyl 4,6- O -benzylidene-α- D -glucopyranoside was separately performed with methyl benzoate and with benzoyl chloride, and the product distributions with the two reagents were compared; methyl 2- O -benzoyl-α- D -glucopyranoside and methyl 3- O -benzoyl-α- D -glucopyranoside were obtained by hydrolysis of the corresponding monobenzoates of methyl 4,6- O -benzylidene-α- D -glucopyranoside. Methyl 4- O - benzoyl-α- D -glucopyranoside was prepared by ring-opening of methyl 4,6- O -benzylidene-α- D -glucopyranoside with N -bromosuccinimide in the presence of water.