Synthesis of polyhydroxylated 7-aminopyrrolizidines and 8-aminoindolizidines

The ammonolysis of a lactone moiety in tricyclic cycloadducts derived from non-racemic five-membered cyclic nitrone and 2(5H)-furanones furnishes an amido function, which after subsequent Hofmann rearrangement, leads to a protected amino group attached to the bicyclic isoxazolidine skeleton. A successive simple transformation, involving cleavage of N-O bond followed by intramolecular N-alkylation, provides an access to the polyhydroxylated 7-aminopyrrolizidines and 8-aminoindolizidines, potential glycosidases inhibitors.