Two Eremophilane-type Sesquiterpenoids from the Rhizomes of Ligularia veitchiana(Hemsl.) Greenm

Two new eremophilane-type sesquiterpenoids eremophil-6-en-11-ol (1) and (7α,9α,10α)-9,10-epoxy-eremophilan-11-ol (2), together with a known eremophilane-type (6α,8α)-6,8-dihydroxyeremophil-7(11)-en-12-oic acid 12,8-lactone (3) were isolated from the rhizomes of Ligularia veitchiana. The structures of 1 and 2 were established by spectral analysis including 1H- and 13C-NMR, HSQC, HMBC, and HR-ESI-MS data. The compounds 1 and 3 were assessed against lung-cancer (A549) and stomach-cancer (BCG823) cell lines by the MTT method. The results showed that 1 exhibited significant inhibiting activities on the growth of these cancer cells with IC50 values between 1–100 μg/ml, whereas compound 3 had no effect on the same cell lines.