The Allyl Group for Protection in Carbohydrate Chemistry, Part 14.¹Synthesis of 2, 3-Di-<u>O</u>-Methyl-4-<u>O</u>-(3, 6-Di-<u>O</u>-Methyl-β-D-Glucopyranosyl)-L-Rhamnopyranose (and its α-Propyl Glycoside): A Haptenic Portion of the Major Glycolipid from<i>Mycobacterium Leprae</i>

Abstract

Abstract 3, 6-Di-O-methyl-d-glucose was prepared via 5-O-allyl-1, 2-O-isopropylidene-3-O-methyl-αd-glucofuranose and was converted into 2, 4-di-O-acetyl-3, 6-di-o-methyl-dD-glucopyranosy 1 chloride. Condensation of the chlorosugar with methanol or allyl 2, 3-O-isopropylidene-α-l-rhamnopyranoside gave the corresponding crystalline β-glycbsides. The allyl 4-O-(2,4-di-O-acetyl-3, 6-di-O-Tnethyl-β-dD-glucopyranosyl)-2, 3-O-isopropylidene-α-l-rhamnopyranoside was converted into the title compounds and into crystalline 2, 3-di-O-acetyl-4-O-(2, 4-di-O-benzyl-3, 6-di-O-methyl-β-d-glucopyranosyl)-l-rhamnopyranosyl chloride which should serve as an intermediate for the synthesis of the trisaccharide portion of the major glycolipid of Mycobacterium leprae.