OCEANAPINS A-F, UNIQUE BRANCHED CERAMIDES ISOLATED FROM THE HAPLOSCLERID SPONGE OCEANAPIA CF TENUIS OF THE CORAL SEA

A series of ceramides, called oceanapins A-F (2-7), which are unique f or branching at both the sphingosine and fatty-acid chains, have been isolated as pure compounds from the haplosclerid sponge Oceanapia cf. tenuis of the Coral Sea. Following acid hydrolysis, both the fatty-aci d and the sphingosine portions were obtained separately, which allowed their unequivocal structural definition. The absolute configuration w as secured via protection of C(1')-OH and Mosher's esterification at C (3')-OH of the oceanapins.