Cytotoxic triterpene saponins from Alternanthera philoxeroides

Four new pentacyclic triterpene saponins, philoxeroidesides A-D (1-4) were isolated from the aerial parts of Alternanthera philoxeroides. Their structures were elucidated on the basis of 1D- and 2D-NMR experiments and MS analyses. Philoxeroidesides A-D (1-4) showed cytotoxic activities against SK-N-SH and HL60 cell lines.