Glaciasterols A and B, 9,11-secosteroids from the marine sponge Aplysillaglacialis

Abstract

The glaciasterols, a family of cytotoxic 9,11-secosteroids, have been isolated from extracts of the northeastern Pacific sponge Aplysillaglacialis. The structures of glaciasterol A (2) and glaciasterol B (3) were elucidated by a combination of spectroscopic analysis and chemical interconversions on the native steroid 2 and the diacetate 5 of glaciasterol B (3).