Two new sesquiterpenes from Artemisia sieversiana

Two new sesquiterpenes, together with 32 known compounds(3-34), were isolated from Artemisia sieversiana Ehrhart ex willd. and the compounds 3-21 were isolated from this plant for the first time. The new compounds were elucidated as 2α,9α-dihydroxymuurol-3(4)-en-12-oic acid (1) and 13α-methyl-(5αH,6αH,7αH,8αH)-austricin 8-O-β-D-glucopyranoside (2), respectively. The structural identification of these compounds was mainly achieved by spectroscopic methods including 1D and 2D NMR techniques, and the structure of compound 1 was confirmed by a single crystal X-ray diffraction experiment. Compounds 1-2 were evaluated for cytotoxic activity in vitro against MCF-7, NCI-H460 and Hep-G2 cell lines, respectively.