Sesquiterpenoids from the Root Bark of Acanthopanax leucorrhizus and Their Biological Activities

Three furoeremophilane-type sesquiterpenoids, including one new, 1 alpha-acetoxy-6 beta-(benzoyloxy)-10 beta-hydroxy-9-oxofuroeremophilane (1), and two known, 1 beta,6 beta-diacetoxy-9-oxofuroeremophilane (2) and (6 alpha)-furoeremophilan-14,6-olide (3), were isolated from the root bark of Acanthopanax leucorrhizus from China. Their structures were elucidated on the basis of comprehensive spectroscopic analyses, including IR, HR-ESI-MS, 1D- and 2D-NMR experiments. A preliminary bioassay revealed that compound 1 exhibits weak cytotoxicities against the human tumor cell lines MCF-7 and SMMC-7721 with the IC50 values of 75.12 +/- 1.69 and 168.36 +/- 2.01 mu g/ml, respectively. Compound 1 and 2 showed moderate activities against Escherichia coli with the MIC values of 32 and 64 mu g/ml, respectively.