New bioactive halenaquinone derivatives from South Pacific marine sponges of the genus Xestospongia

Two new derivatives named xestosaprol C methylacetal 7 and orhalquinone 8 of halenaquinone-type polyketides were isolated from marine sponges of the genus Xestospongia collected in South Pacific. Structure-activity relationship studies of PLA2, FTase, and Plasmodium falciparum inhibitors are presented.