Oxidation of GlcNAc thiazoline in the presence of an alcohol affords no glycosidation products, but rather the alkyl alpha-GlcNAc 1-C-sulfonate. E2 cleavage of the sulfonate ester and then O-deacetylation gives the alpha-GlcNAc 1-C-sulfonic acid, a new type of carbohydrate derivative. (C) 2002 Elsevier Science Ltd. All rights reserved.