Camganoids A and B, two new sesquiterpenes with different carbon skeletons isolated from fruits of Cinnamomum migao
Yongzhen Xiao, Ishaq Muhammad, Xian-peng Ma, Huajun Yu, Shikai Yan, Xue Xiao, Hui‐Zi Jin
Abstract
To isolate and identify the undescribed compounds from the fruits of Cinnamomum migao and evaluate its nitric oxide inhibition potential. The chromatographic techniques of silica gel, Sephadex, and HPLC were used for isolation and purification of the compounds, while HR-ESI-MS, 1D NMR, 2D NMR, ECD, and X-ray diffraction techniques were used to characterize and confirm the isolated compounds. Moreover, the anti-inflammatory activity of the isolated compounds was carried out to check inhibitory potential against the production of nitric oxide with RAW264.7 cells stimulated by LPS. Camganoid A (1), a novel sesquiterpene possessing an unprecedented skeleton, and camganoid B (2), containing a unique eight-membered sesquiterpene moiety with a new carbon skeleton, were isolated and identified from the fruits of C. migao. The absolute configurations of 1 and 2 were confirmed by single crystal X-ray diffraction and electronic circular dichroism (ECD) calculations. Among these compounds, compound 1 exhibited potent inhibitory activity against the production of nitric oxide with IC50 value of 4.59 μmol/L in RAW264.7 cells stimulated by LPS. The isolation of two new skeletons from the fruits part of C. migao possessed unique skeletons which have not been reported before.