Fortisterol, a novel steroid with an unusual seven-membered lactone ring B from the Chinese marine sponge Biemna fortis Topsent

Abstract

Fortisterol (1), a novel steroid with a rare seven-membered lactone ring B, has been isolated from the marine sponge Biemna fortis and its structure gas been elucidated on the basis of spectroscopic data.

Keywords:

• Biemna fortis Topsent
• Marine sponge
• Fortisterol

Acknowledgements

This research is financially supported by the “National Science Foundation for Outstanding Chinese Youth” (No. 30125044), National 863 project (2001AA620403) and the “National Natural Science Foundation” (No. 30170106).