(6β,7α,9S,11α,18S)-16,17-Didehydroormosanine

An Orrnosia alkaloid, this base occurs in O. sernicastrata. It has been assigned the structure given above but there is still some dubiety regarding this since the same structure has recently been given to Podopetaline (q.v.).

McLean et aT., Can. 1. Chern., 49, 1976 (1971)
McLean et aT., ibid, 50, 1639 (1972)