2-Deoxy-2-trichloroacetamido-D-glucopyranose derivatives in oligosaccharide synthesis: from hyaluronic acid to chondroitin 4-sulfate trisaccharides

Abstract

Suitably protected derivatives of phenyl 2-deoxy-1-thio-2-trichloroacetamido-β-D-glucopyranoside, 6, 15 and 16, a new class of glycosyl donors, were tested in the reaction with sugar acceptors of low reactivity (i.e. the methyl uronate 2). This methodology was applied to the stereocontrolled and high-yielding construction of the hyaluronic acid trisaccharide derivative 26. Selective inversion of configuration at C-4 of the central D-glucosamine unit, transformation of the N-trichloroacetyl group into N-acetyl, O-sulfation, and final deprotection afforded the corresponding chondroitin 4-sulfate trisaccharide derivative 30 in high yield.