Amphiasterins : a new family of cytotoxic metabolites from the marine sponge Plakortis quasiamphiaster

A new family of marine metabolites, named amphiasterins (1-17), was isolated from the marine sponge Plakortis quasiamphiaster. They can be divided in five structurally homogeneous groups, whose components differ only in the length and/or in the unsaturation degree of the alkyl side chain. The structures of these compounds were elucidated by spectroscopic data.