Abstract
A new sesquiterpene cacaroborin (1) was isolated from the roots of Cacalia roborowskii, together with three known ones, cinalbicol (2), isopetasin (3), and 3α-angeloyloxylactone (4). The structure of compound 1 was elucidated as 1β,10α-dihydroxy-8α-methoxyeremophil-7(11)-en-8β,12-olide on the basis of spectral evidence (1D, 2D NMR, IR, EI-MS, and HR-ESI-MS) and X-ray diffraction analysis.
Acknowledgements
We thank Prof. Zhong-Jian Jia of the College of Chemistry and Chemical Engineering, Lanzhou University for supporting our work.