Ding, Ao-Xue, Shan, Yi-Ming, Li, Chen-Yue, Qin, Guo-Qing, Chen, Tong, Wang, Qing, Hu, Xiang-Gang, Guo, Peng-Ju, Yu, Hai-Jun, Wang, Wen-Qiong, and Xuan, Li-Jiang
Eight previously undescribed sesquiterpene lactones (1 – 8), together with six known ones (9 – 14) were isolated from the aerial parts of Tithonia diversifolia (Hemsl.) A. Gray. The absolute configurations of these compounds were elucidated using HRMS, NMR spectroscopy, optical rotation measurements, X-ray crystallography, and ECD. Among them, sesquiterpene lactones 2 – 4 share a unique carbon skeleton with a rare C-3/C-4 ring-opened structure. Compounds 1 and 8 showed moderate inhibitory effects toward CT26 murine colon carcinoma cells by promoting lipid ROS production, highlighting their potential as ferroptosis inducers. [Display omitted] • Eight undescribed sesquiterpene lactones were isolated from Tithonia diversifolia. • 2 – 4 were 3,4-seco-sesquiterpene lactones. • 1 and 8 could promote lipid ROS production, acting as new ferroptosis inducers. [ABSTRACT FROM AUTHOR]