Synthesis of a carbasugar analogue of a putative intermediate in the UDP-Galp-mutase catalyzed isomerization

[GRAPHICS] The synthesis of the carbasugar analogue of 1,4-anhydro-beta-D-galactopyranose, a proposed intermediate in the reaction catalyzed by uridine diphosphate-alpha-D-Galp mutase, in racemic form via Diels-Alder and Barton decarboxylation chemistry is reported. This compound was found not to inhibit the mutase from Mycobacterium tuberculosis, indicating that the enzyme does not possess a 1,4-anhydro-beta-D-galactopyranose binding pocket.