Cytotoxic sesquiterpenoids from Ligularia pleurocaulis

Five sesquiterpenoids, including an eremophilenolide dimer (1), were isolated from whole plants of Ligularia pleurocaulis. Together with eight known sesquiterpenoids, all 13 compounds were evaluated for their cytotoxicity against three cancer cell lines (MCF-7, HepG2 and A549) by the MTT assay, where 1 showed moderate activities with IC50 in the range of 5.2-8.4 μM.