| 摘要 |
PURPOSE:To obtain the subject inhibitor contained in bark of Picea jezoensis of pinaceous plant, effective for preventing and suppressing carcinogenesis and recurrence of cancer, having inhibitory action on carcinogenic promoter by effectively utilizing bark and tree of pine and oak trees which have not much used in forest operation. CONSTITUTION:Bark of collected Picea jezoensis is roughly cut, air-dried, oozed out with a purified ether five times, the oozed solution is concentrated to give an ether essence, which is subjected to silica gel column chromatography, developed and eluted firstly with chloroform and secondarily with a mixed solvent of chloroform and ethyl acetate. The chloroform-eluted part is subjected to silica get column chromatography, eluted with a mixed solvent of n-hexane and chloroform, the solvent of the eluted fraction is distilled away and the fraction is recrystallized from methanol-chloroform to give the objective triterpenoid of formula I (R<1> is oxo or beta-hydroxyl group; R<2> is alpha-methoxy or oxo; D ring is group of formula II, formula III, etc.) effective for preventing and suppressing carcinogenesis and recurrence of cancer. |
