CONVERSION OF DELTA-(SULFONYL)AMINO-ALPHA-EPOXY KETONES TO BICYCLIC KETOPYRROLES VIA INTRAMOLECULAR CONJUGATE-ADDITION TO AZOENE INTERMEDIATES - SYNTHESIS OF THE BICYCLIC KETOPYRROLE CORE OF THE 1-AZAFULVENE ROSEOPHILIN
Sh. Kim et Pl. Fuchs, CONVERSION OF DELTA-(SULFONYL)AMINO-ALPHA-EPOXY KETONES TO BICYCLIC KETOPYRROLES VIA INTRAMOLECULAR CONJUGATE-ADDITION TO AZOENE INTERMEDIATES - SYNTHESIS OF THE BICYCLIC KETOPYRROLE CORE OF THE 1-AZAFULVENE ROSEOPHILIN, Tetrahedron letters, 37(15), 1996, pp. 2545-2548
Reaction of delta-(sulfonyl)amino-alpha-epoxy ketones with dimethylhyd
razine results in cyclization to pyrrolidine-fused beta-hydroxy dimeth
ylhydrazones. elimination affords dihydropyrroles which can be convert
ed to sulfonyl-protected ketopyrroles via oxidation with NIS; alternat
ively, treatment with DBU affords N-H bearing ketopyrroles. Copyright
(C) 1996 Elsevier Science Ltd