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[reaction: see text] A divergent strategy for the synthesis of diverse azabicyclic ring systems has been developed in which a chiral N-allylpyrrolidine derivative, obtained from a carbohydrate precursor was converted to (-)-8-epi-swainsonine triacetate by RCM and to a pyrrolo[1,2-a]azepine derivative and a 3-hydroxymethyl-substituted indolizidine by N-allylcarbohydrate nitrone and nitrile oxide cycloadditions.

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It is demonstrated that the N-phenyl nitrones derived from carbohydrates (Ia)-(Id) undergo improved intramolecular 1,3-dipolar cycloaddition compared to the previously reported N-Me or N-Bn nitrones. Oxepane products are obtained in better yields or together with the pyran skeletons [cf. (V)]. In the case of (Ie), only the pyran is formed in analogy to the N-Me analogue. -(DATTA, S.; NATH, M.; CHOWDHURY, S.; BHATTACHARJYA*, A.; Tetrahedron Lett. 49 (2008) 18, 2935-2938; Dep. Chem., Indian Inst. Chem. Biol., Kolkata 700 032, India; Eng.) -Lindner 33-173