Terpenoids and sterols from Saussurea cauloptera.

A total of 27 natural products were isolated from Saussurea cauloptera, including two new eudesmane-type sesquiterpenoids, the gerin derivatives 2 and 3, and one new ent-labdane diterpenoid, compound 9. The known compounds included six sesquiterpenoids, eleven triterpenoids, six sterols, and one lignan. Their structures were elucidated on the basis of extensive spectroscopic and mass-spectrometric analyses, as well as by X-ray crystallography in the case of gerin (1). The structurally related compounds 1-4 were found to exhibit strong inhibitory activities against human gastric carcinoma (SGC-7901) cells.