Isolation, Structural Elucidation, and Cytotoxicity of Three Newent-Kaurane Diterpenoids fromIsodon japonicavar.glaucocalyx

Authors:
  • YZYun-Xiao Zhang
    Yun-Xiao Zhang
  • GHGuang-Fan Hai
    Guang-Fan Hai
  • SBSu-Ping Bai
    Su-Ping Bai
  • YYYong-Liang Yuan
    Yong-Liang Yuan
  • DYDan-Dan Ye
    Dan-Dan Ye
  • NZNan-Qian Zhou
    Nan-Qian Zhou
Publisher website
Google Scholar
Abstract
Three new ent-kaurane diterpenoids, glaucocalyxin H (1), glaucocalyxin I (2), and glaucocalyxin J (3), together with four known diterpenoids (4-7), were isolated from the leaves of Isodon japonica Hara var. glaucocalyx. Their structures were elucidated by spectroscopic analysis, and the structures of compounds 2 and 3 were further confirmed by X-ray crystallographic analysis. Compounds 1, 4, and 5 were evaluated for their cytotoxicity in vitro against CE-1, U87, A-549, MCF-7, Hela, K-562, and HepG-2 human tumor cell lines. Compound 1 showed potent inhibitory activities against six tumor cell lines with IC50 values ranging from 1.86–10.95 µM, and compounds 4 and 5 exhibited significant selective cytotoxicity on seven tumor cell lines.