Three New Cytotoxic Steroidal Glycosides Isolated from Conus pulicarius Collected in Kosrae, Micronesia

Three new sulfated steroidal glycosides (3-5), along with known cholesterol derivatives (1,2), were isolated from the visceral extract of the cone snail Conus pulicarius. The structure of each new compound was elucidated by nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry. The three new compounds exhibited significant in vitro cytotoxicity (GI(50) values down to 0.49 mu M) against the K562 human leukemia cell line.