Preparation of Three Positional Isomers of Diglucosyl-cyclomaltohexaose

Abstract

Three positional isomers of diglucosyl-cyclomaltohexaose (diglucosyl-cG6) were chemically synthesized via 61,62-, 6\\\\\\\\63-, and 61,64-di-0-(tm-butyldirnethylsilyl)-cG6s (1, 2, and 3) prepared regiospecifically. Glucosylation of bis(2,3-di-0-acetyl)tetrakis(2,3,6-tri-0-acetyl)-cG6s obtained from the three regioisomeric compounds 1, 2, and 3 with 2,3,4,6-tetra-0-benzyl-l-0-trichloroacetimidoyl-a-D-glucopyranose, followed by debenzylation and then deacetylation, afforded b1^2-, 6l963-, and b^b^di-O-Ca-D-glucopyranosylJ-cGgS (10,11, and 12) together with configurational isomers. The desired compounds 10, 11, and 12 containing two (l->6)-a-linkages were isolated from the mixtures of their configurational isomers by high performance liquid chromatography. The three diglucosyl-cG6s synthesized chemically were used as authentic samples to identify the components in a mixture of diglucosyl-cG6s produced by an enzymatic process. © 1992, The Pharmaceutical Society of Japan. All rights reserved.