2-DEOXY-2-TRICHLOROACETAMIDO-D-GLUCOPYRANOSE DERIVATIVES IN OLIGOSACCHARIDE SYNTHESIS - FROM HYALURONIC-ACID TO CHONDROITIN 4-SULFATE TRISACCHARIDES

Suitably protected derivatives of phenyl. 2-deoxy-1-thio-2-trichloroacetamido-beta-D-glucopyranoside, 6, 15 and 16, a new class of glycosyl donors, were tested in the reaction with sugar accepters of low reactivity (ie. 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.