New manzamine alkaloids, zamamidines A (1) and B (2), have been isolated from an Okinawan marine sponge Amphimedon species. The structures and stereochemistry of 1 and 2 were elucidated from the spectroscopic data and conformational analysis. Zamamidines A (1) and B (2) are the first manzamine alkaloids possessing a second //-carboline ring via an ethylene unit at N-2 of manzamine H and 1,2,3,4-tetrahydromanzamine B, respectively.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry