Enantiospecific Synthesis of Swainsonine, (1S, 2R, 8R, 8aR)-1,2,8-trihydroxyoctahydroindolizine, from D-mannose

An enantiospecific synthesis of swainsonine from D-mannose is described; the heterocyclic rings of swainsonine are constructed by two intramolecular reductive aminations caused by the catalytic hydrogenation of an azidoaldehyde with 5 equivalents of hydrogen. © 1984.