23092-97-9 3,8-Didehydro-12,18-dihydroxysenecionan-11,16-dione Dehydroretrorsine Dehydroretrosine Retrorsine didehydro- Retrorsine pyrrole Senecionan-11,16-dione, 3,8-didehydro-12,18-dihydroxy-