Identification of the new 11,15-icosadienoic acid and related acids in the sponge Amphimedon complanata.

The total phospholipid fatty acids from the Caribbean sponge Amphimedon complanata were studied, revealing the presence of the new 11,15-icosadienoic acid [1], the rare 7-methyl-6-hexadecenoic acid [2], and the recently discovered 6,11-icosadienoic acid. These acids were mainly encountered in phosphatidylethanolamine and phosphatidylcholine.