Baeyer–Villiger-type oxidation of an immonium group: the structural establishment of naturally occurring amides related to benzo[c]phenanthridine alkaloids

Abstract

Structures of four new amide-alkaloids, arnottianamide (1), isoarnottianamide (2), integriamide (3), and iwamide (4), which occur naturally in Xanthoxylum plants, were established by derivation from the known benzo[c]phenanthridine alkaloids chelerythrine (5), nitidine (6), avicine (7), and decarine (8). In these transformations, the novel Baeyer–Villiger-type oxidation of an immonium group was applied.