Flavonol Glycosides and Cytotoxic Steroidal Saponins from Furcraea tuberosa (Agavaceae)

Phytochemical analysis of the mature fruits of Furcraea tuberosa (Agavaceae) resulted in the isolation of a new bisdesmosidic spirostanol saponin (1), along with eight known steroidal glycosides (2-9), one known phenolic carboxylic acid ester (10) and three known flavonol glycosides (11-13). The structures of these compounds were assigned using a combination of ID and 2D NMR techniques including ¹H, ¹³C, COSY, TOCSY, HSQC and HMBC NMR, and confirmed by mass spectrometry. Thus the new saponin was elucidated as (25R)-6α-(β-D-glucopyranosyloxy)-5α-spirostane-3β-Ο-[(6-Ο-hexadecanoyl)-β-D- glucopyranoside]. The literature survey revealed that most of the steroidal saponins isolated have shown potent cytotoxic effects against various human cancer cell lines and the results are herein reviewed.