Jaspamides H-L, new actin-targeting depsipeptides from the sponge Jaspis splendans

Continued investigation of cytotoxic extracts of the marine sponge Jaspis splendans has resulted in the discovery of jaspamides H-L (2-5). Their structures were determined by interpretation of their NMR and ESIMS data. All compounds exhibited potent cytotoxic activities and were shown to cause microfilament disruption. Biological activity and structural elucidation are reported here.