Four new terpenoids from the roots of Ligularia narynensis.

Four new oplopane and guaiane type sesquiterpenoids (1-3), and a monoterpenoid (4) together with three known monoterpenoids (5-7), have been isolated from the roots of Ligularia narynensis. The structures of 1-4 were elucidated as 3beta,4-diacetoxy-8alpha-(2-methylbutyryloxy)-9alpha-(4-methylsenecioyloxy)-11alpha,12-epoxyoplop-10 (14)-ene (1), 3beta,4-diacetoxy-9alpha-(4-acetoxy-4-methylsenecioyloxy)-2beta,8alpha-di (2-methylbutyryloxy)-11alpha,12-epoxyoplop-10 (14)-ene (2), 2alpha-hydroxy-1betaH,7alphaH,10alphaH-guai-4,11 (12)-dien-3-one (3) and 1alpha,2beta,3alpha,6alpha-tetrahydroxy-p-menthane (4) by spectroscopic methods. 1 and 2 were evaluated for their in vitro cytotoxic activity against cultured SMMC-7721 (human hepatoma), L02 (human hepatocyte), and HL-60 (human promyelocytic leukaemia) cell lines.