Cytotoxic compounds from Polygala vulgaris.

To search for antitumor agents from plants, we studied Polygala vulgaris since cytotoxic lignans are known to occur in some Polygala species. Preliminary data on plant petrol ether, chloroform, and methanol extracts from the roots and aerial parts, showed in vitro cytotoxic activity against the solid tumor LoVo cell line. Fractionation of the active extracts led to the isolation of three new compounds, a derivative of aucuparine and two xanthones, as well as a known methylsinapate. All compounds were tested for in vitro cytotoxic activity using two cell lines, LoVo and its strain, which express resistance to common antitumor agents.