Triterpenoids and lignans from the stems of Tripterygium wilfordii and their hepatoprotective activities.

Five undescribed triterpenoids (1-5), two undescribed lignans (6, 7), as well as nine known triterpenoids (8-16), were isolated from the stems of Tripterygium wilfordii. The structures of these new compounds were established via comprehensive spectroscopic analyses, and their absolute configurations were definitely confirmed by ECD computational simulation. Bioactivity evaluation revealed that several isolated compounds exhibited notable hepatoprotective effects.