Three bioactive sesquiterpene quinones from the Fijian marine sponge of the genus Hippospongia.

A sesquiterpenoid quinone, epi-ilimaquinone (1), and two sesquiterpene amino quinones, smenospongine (2) and glycinylilimaquinone (3), were isolated from the Fijian marine sponge Hippospongia sp. The structures of these compounds were determined by spectroscopic analysis. Compounds 1 and 3 were reported for the first time in this study from the sponge of the genus Hippospongia. Compound 1 displayed potent cytotoxic activity and showed antibacterial activity against methicillin-resistant Staphylococcus aureus, wild type S. aureus and vancomycin-resistant Enterococcus faecium and displayed antifungal activity against amphotericin-resistant Candida albicans while compounds 2 and 3 showed moderate cytotoxic activity. However, compound 1 did not show appreciable antifungal activity against wild type C. albicans, Cryptococcus neoformans, Aspergillus niger, Penicillium sp., Rhizopus sporangia or Sordaria sp.