A novel approach to carbohydrate clusters: the regioselective synthesis of non-glycosidically linked oligosaccharides

Abstract

Dialkylstannylene acetals derived from a number of different carbohydrates having both cis- and trans-1,2-diols free were reacted with diacyl chlorides and disulfonyl chlorides in the presence of tertiary amines at room temperature to give symmetrical non-glycosidically linked disaccharides with excellent regioselectivity and in excellent yield. The regioselectivity obtained was the same as that previously found in acylation reactions of the same substrates. In one case, a symmetric non-glycosidically linked diasaccharide was also obtained in excellent yield. For methyl 4,6-O-benzylidene-α-D-glucopyranoside, a 16-membered ring macrocyclic tetralactone was obtained in 50% yield by altering the reaction stoichiometry and performing the reaction at 80 °C. Keywords: carbohydrates, clusters, non-glycosidically linked oligosaccharides, disaccharides, trisaccharides.