Three new steroidal saponins from Aspidistra letreae plants and their cytotoxic activities

Three new steroidal saponins, aspiletreins A-C (1-3), together with 2H-chromen-2-one (4), and alpha-tocopherol (5), were isolated from whole Aspidistra letreae plants collected in Vietnam. Their structures were elucidated by a combination of spectroscopic analyses, including 1D- and 2D-NMR, IR, and HRESIMS, and by comparison with the reported data in the literature. Compounds 1-3 exhibited moderate cytotoxicities against the LU-1, HeLa, MDA-MB-231, HepG2, and MKN-7 human cancer cell lines, with IC50 values ranging from 7.69 +/- 0.40 to 20.46 +/- 3.11 microM.