Cytotoxic alkaloids of Pachysandra terminalis.

Four steroidal alkaloids, epipachysamines B (1) and E (2), pachystermine A (3) and pachysamine E (4), were isolated as cytotoxic principles from the MeOH extract of the stems of Pachysandra terminalis SIEB. et ZUCC. (Buxaceae). These alkaloids showed cytotoxic activity against P388 and P388/ADR leukemia cells in vitro. Three of the alkaloids (1-3) were previously isolated from this plant material, and this is the first report of their cytotoxic activity. Pachysamine E (4) is a new alkaloid.