Structural reappraisal of corticatic acids,biologically active linear polyacetylenes,from a marine sponge of the genus <Emphasis Type="Italic">Petrosia</Emphasis>

Structural reinvestigation of corticatic acid A from a marine sponge, Petrosia sp., resulted in the revision of its structure, which conformed to the structural features of the biosynthetically related linear acetylenes isolated from Petrosia sp. In the process of isolating an authentic corticatic acid A, we isolated three new congeners and determined their structures. We also suggested that the structures of other corticatic acids need revision.