Two new pregnane alkaloids from Pachysandra terminalis Sieb. et Zucc. and their cytotoxic activities

Pactermines E and F (1 and 2), two new pregnane alkaloids were isolated from the whole plant of Pachysandra terminalis Sieb. et Zucc. Their structures were determined by physicochemical properties and spectroscopic methods including 1D, 2D NMR, IR, HR-ESI-MS data. Cytotoxic activities against three human cancer A549, HCT116 and SW620 cell lines of the isolated compounds were evaluated by CCK8 method. However, all compounds showed no significant activity against the three cancer cells (IC₅₀>100 μM) except for compound 1, which showed inhibitory effects against HCT116 cells with IC₅₀ values of 84.6 μM.