Quinone Methide Triterpenes from Tripterygium regelii

Chloroform extracts of Tripterygium regelii dried root bark afforded three cytotoxic quinone methides, which were identified as pristimerine (1), celastrol (2), and -hydroxy tingenone (3) on the basis of chemical and spectroscopic studies. Compounds 1-3 showed significant cytotoxic against A549 and SK-OV3 human cancer cell lines, and antibacterial activities against Gram-positive bacteria. 1 was isolated from this plant for the first time.