Abstract

Artemisia annuais a well-known traditional Chinese medicine. Due to its highest antimalarial efficacy, China has a long history of cultivatingA. annua, and it is used for “clearing heat and detoxicating”. Several, studies have shown that theA. annuaextract exerts cytotoxicity. In order to clarify the basis of the cytotoxic effect ofA. annua, 18 sesquiterpenes were isolated from the herb, including 2 new sesquiterpenes and 16 known analogues. The structures of new compounds were elucidated by comprehensive spectroscopic analyses, including HR-ESI-MS, NMR experiments, single-crystal X-ray, and DP4+ and electronic circular dichroism (ECD) calculations. Cytotoxic activity screening revealed three compounds that exhibited cytotoxicity in a dose-dependent manner. Additional exploration showed that compound5significantly inhibited the proliferation of CT26 and HCT116 cells and induced apoptosis of HCT116 cells after 24 h. These chemical constituents contributed to elucidating the mechanism of action of the cytotoxic activity ofA. annua.Keywords:Artemisia annua;Asteraceae;sesquiterpenes;cytotoxic