Dendrinolide, a New Degraded Diterpenoid from the Antarctic Sponge Dendrilla membranosa

A new glacian diterpenoid, named dendrinolide ( 5 ), was isolated, together with the 9,11-dihydrogracilin A ( 1 ), from the Me 2 CO extract of the Antarctic sponge Dendrilla membranosa. Its structure has been elucidated by interpretation of spectral data and comparison with the similar product 6, previously found in the Mediterranean sponge Spongionella gracilis .