Synthesis of some 3-O, 4-O, and 3,4-di-O-glycosyl-substituted methyl α-D-galactopyranosides

Abstract

Seven disaccharide and eight trisaccharide methyl glycosides required for n.m.r. and conformational studies have been synthesized. They are all derivatives of methyl α-D-galactopyranoside which has been 3-O-, 4-O-, or 3,4-di-O-glycosylated with either L-fuco- or D-gluco-pyranosyl groups. All anomeric forms were synthesized, either via thioglycosides and methyl triflate promotion or via glycosyl bromides and silver triflate promotion.