[A short path to synthesis of 4-deoxy-4-fluoroglucosaminides: methylumbelliferyl N-acetyl-4-deoxy-4-fluoro-beta-D-glucosaminide].

A convenient method of synthesis of 1,6-anhydro-4-deoxy-2-O-tosyl-4-fluoro-beta-D-glucopyranose by fusion of 1,6;3,4-dianhydro-2-O-tosyl-beta-D-galactopyranose with 2,4,6-trimethylpyridinium fluoride was found. By successive action of ammonia, methyl trifluoroacetate, and acetic anhydride, the resulting compound was transformed into 1,6-anhydro-3-O-acetyl-2,4-dideoxy-2-trifluoroacetamido-4-fluoro-beta-D-glucopyranose, which was converted into 3,6-di-O-acetyl-2,4-dideoxy-2-trifluoroacetamido-4-fluoro-alpha-D-glucopyranosyl fluoride by the reaction with HF/Py. The resulting fluoride was further used as a glycosyl donor in the synthesis of methylumbelliferyl N-acetyl-4-deoxy-4-fluoro-beta-D-glucosaminide.