A New Sesquiterpene Lactone fromEupatorium chinenseand its Anti-TNBC Activity

A new sesquiterpene lactone, namely, eupachiilide A (1), as well as two known sesquiterpene lactones, eupachinilide B (2), and eupalinilide G (3), were isolated from the whole plant of Eupatorium chinense L. The new structure was elucidated by spectral methods, especially 2D NMR techniques. The three natural compounds were all Michael addition acceptors, whose electrophilic moiety could react with the nucleophilic residues of the relevant active site and produce a variety of bioactivities. Eupachiilide A demonstrated potent cytotoxicity against two TNBC cell lines.