A New Megastigmane Alkaloid from Pachysandra terminalis with Antitumor Metastasis Effect

9-(N,N-Dimethyl)-4,7-megastigmedien-3-one (1) was isolated from Pachysandra terminalis and identified by 1D and 2D NMR spectroscopic and mass spectrometric methods. Compound 1 revealed significant anti-metastasis effect on cancer cell migration and invasion through suppressing the expressions of p-PKCζ and p-integrin β1 in human breast cancer cells, and also showed anti-angiogenic activity on human umbilical vein endothelial cells.