Lipodiscamides A-C, new cytotoxic lipopeptides from Discodermia kiiensis.

Lipodiscamides A-C, three new lipodepsipeptides, were characterized from the marine sponge Discodermia kiiensis. These structurally rare cyclic lipodepsipeptides were found to possess an unprecedented dilactone macrocycle and, thus, represent a new family of lipopeptides. They are the only lipopeptides bearing 4S-hydroxy-trans-2-enoate, and noncanonical amino acids, l-3-ureidoalanine (Uda), E-dehydronorvaline (Denor), and d-citrulline (Cit). MTT assays against P388 and HeLa cells revealed the moderate cytotoxicity of all three compounds.