The four 5-alkenyl-1-pyrroline 1-oxide-5-carboxylic esters 1-4 undergo regi
oselective intramolecular cycloaddition to give the cycloadducts 5-8, which
can be hydrogenolyzed to generate a range of azabicyclic compounds and unu
sual cyclic amino esters. (C) 1999 Academic Press.