Cytotoxic sesquiterpene lactones from Artemisia myriantha

Chemical exploration of Artemisia myriantha Wall. ex Bess (Asteraceae) aerial parts afforded one new seco-guaianolide (1) and one new germacranolide (2). Structure elucidation of the new compounds was un-ambiguously performed based on HRESIMS, 1D and 2D NMR spectroscopic analyses. The two new compounds exhibited in vitro strong cytotoxic activities against human cancer cell lines HCT-8 with IC50 values of 0.76 and 0.28 mu M, respectively.