Cytotoxic Psammaplysin Analogs from Marine Sponge Suberea sp. and Role of Spirooxepinisoxazoline Ring in Their Activity

Abstract

Seventeen bromotyrosine-derived metabolites, including eight new compounds, were isolated from the Micronesian sponge of the genus Suberea. Four of the new compounds were psammaplysin derivatives and the other four were ceratinamine derivatives. Of the compounds obtained, psammaplysins exhibited high cytotoxicity against human cancer cell lines (GI50 values down to 0.8 μM), while ceratinamine and moloka’iamine analogs showed almost no activity. These results suggest that the spirooxepinisoxazoline ring is a requirement for cytotoxicity, and therefore, may serve as an attractive molecular scaffold for the development of a potent anticancer agent.ives. Of the compounds obtained, psammaplysins exhibited high cytotoxicity against human cancer cell lines (GI50 values down to 0.8 μM), while ceratinamine and moloka’iamine analogs showed almost no activity. These results suggest that the spirooxepinisoxazoline ring is a requirement for cytotoxicity, and therefore, may serve as an attractive molecular scaffold for the development of a potent anticancer agent.