Cleavage of the N-O bond in the 4-spirocyclopropaneisoxazolidine carboxylate and subsequent cycloaddition ☆

1, 3 - Dipolar cycloaddition of nitrones to the double carbon – carbon bond of acceptor ring substituted methylene¬cyclo¬pro¬pa¬nes affords thermally stable regioisomeric 4 - spirocyclopropane isoxazolidines. Cleavage of the N - O bond in 4 - spirocyclopropane isoxazolidines with ester groups on the three - membered ring by the action of activated zinc dust in acetic acid gives the corespoding 1, 3 - amino ancohols containing cyclopropyl ring, whose subsequent cyclization under the reaction conditions yield bi- or tri - cyclic lactams or lactones with retention of the three - membered ring - structural moieties of antibiotics and biologically active compounds.