Abstract: Suan Zau Ren (the seeds of Zizyphus spinosus Hu) is a widely used chinese traditional drag for treatment of insomnia, neurasthenia and sometimes for sleepiness caused by physical emaciation in chinese traditional medicine. Its dichloromethane extract afforded four pentacyclic triterpenes of the lup-20(29)-en group, namely betulin (Ⅱ), betulinic acid(Ⅰ), ceanothic acid(Ⅲ), and alphitolic acid (Ⅳ), and one sterol, daucosterol (Ⅴ). Their structures were identified by the spectroscopic analysis. The later three compounds were isolated from Suan Zau Ren for the first time.

Key words: Zizyphus spinosus Hu, triterpene, betulin, betulinic acid, ceano- thic acid, alphitolic acid daucosterol