A new elemanolide sesquiterpene lactone fromElephantopus scaber

A new elemanolide sesquiterpene lactone, named elescaberin (1), together with two known compounds, namely, isodeoxyelephantopin (2) and deoxyelephantopin (3), was isolated from the whole plant of Elephantopus scaber. The structure of 1 was elucidated on the basis of spectroscopic analysis. All three compounds exhibited significant inhibitory activities against human SMMC-7721 liver cancer cells in vitro (IC(50) 8.18-14.08 micromol/l).