SYNTHESIS AND UTILITY OF ENZOYLOXYIMINO)-2-DEOXY-ALPHA-D-LYXO-HEXOPYRANOSYL BROMIDE AS A NOVEL ALPHA-D-TALOSAMINIDE BUILDING-BLOCK

A novel alpha-D-talosaminyl donor, enzoyloxyimino)-2-deoxy-alpha-D-lyx o-hexopyranosyl bromide has been synthesized in a total yield of 32% o ver 6 steps from D-galactose. The utility of the donor was evaluated f or the elaboration of alpha-D-TalNAc-(1-->6)-alpha-D-Gal, alpha-D-TalN Ac-(1-->6)-alpha-D-Glc, and alpha-D-TalNAc-(1-->3)-L-serine derivative s by a simple 3-step sequence, comprising a-selective glycosylation of appropriately protected accepters of D-galactose, D-glucose, and L-se rine, tale-selective hydroboration of the oxyimino function to an amin o group, and N-acetylation.