Synthesis of an eight carbon homologue of alpha-homomannojirimycin via a bicyclic aminolactone

A thermally induced intramolecular 1,3-dipolar cycloaddition of an azidoest er and subsequent sodium cyanoborohydride reduction of the resulting bicycl ic vinylogous urethane to give a bicyclic aminolactone allows access to an eight carbon homologue of alpha-homomannojirimycin which is a weak fucosida se inhibitor. Intermediates with both an alpha- and beta-amino acid moiety are described and may be useful for incorporation of homopipecolic acids in to novel peptide libraries. (C) 1998 Elsevier Science Ltd. All rights reser ved.