Aspidiatas C and D, two new spirostanol saponins from Aspidistra triradiata and their cytotoxic activities.

Aspidiatas C and D ( 1 and 2 ), two new spirostanol saponins, were isolated along with two known compounds, (25  R* )-spirost-5-en-3 β -yl α -L-rhamnopyranosyl-(1→4)- α -L-rhamnopyranosyl-(1→4)-[ α -L-rhamnopyranosyl-(1→2)]- β -D-glucopyranoside ( 3 ), (25  R* )-spirost-5-en-3 β -yl α -L-rhamnopyranosyl-(1→4)- α -L-rhamnopyranosyl-(1→4)- β -D-glucopyranoside ( 4 ) from the whole plant of Aspidistra triradiata collected in Vietnam. The chemical structures were determined by HRESIMS, 1D- and 2D-NMR analysis, and comparison with published data. Compound 3 exhibited potent cytotoxicity against MCF7, HepG2, SK-LU-1, and HT-29 human cancer cell lines with IC 50 values ranging from 0.19 to 0.65 µM. Compounds 1 , 2 , and 4 displayed moderate cytotoxic effects with IC 50 values ranging from 12.32 to 82.27 µM. Compounds 1 - 4 were isolated from the genus Aspidistra for the first time.