Three New Cytotoxic Sesterterpenes from the Marine Sponge <i>Hyrtios</i> cf. <i>erectus</i>

Abstract

Three new cytotoxic sesterterpenes, 1-3, have been isolated from the marine sponge Hyrtios cf. erectus. Their structures have been determined by interpretation of NMR data. They exhibited cytotoxicity against P-388 murine leukemia cells with IC50 values of 0.4-2.1 micrograms/mL.