Steroidal Saponins from the Mesocarp of the Fruits of Raphia farinifera (Arecaceae) and their Cytotoxic Activity

Eight steroidal saponins (1–8), including one previously unreported derivative (1), have been isolated from the mesocarp of Raphia farinifera fruits by combined column chromatography and RP-HPLC methods. They were characterized by spectroscopic (1D and 2D NMR experiments) and spectrometric (ESIMS) methods, as well as by comparison of their spectral data with those of reported compounds in the literature. All the isolated compounds were tested for cytotoxicity against urinary bladder carcinoma cells (ECV-304). Our results revealed that, for a high cytotoxicity, a sugar chain of at least three sugar moieties attached to C-3 of the steroidal saponin is necessary.