Melophluosides A and B, new triterpene galactosides from the marine sponge Melophlus sarasinorum

Abstract Two new triterpene galactosides, melophluosides A and B, were isolated from a marine sponge Melophlus sarasinorum collected in Indonesia. Their structures were determined by the analysis of spectroscopic data and chemical reactions. The absolute configuration of cyclohexenone moiety was determined by the calculated ECD spectrum of a simplified model. Melophluosides A and B exhibited moderate cytotoxicity against HeLa cells (IC50, 11.6 and 9.7 µM, respectively).