Camganoids A and B, two new sesquiterpenes with different carbon skeletons isolated from fruits of Cinnamomum migao

OBJECTIVE: To isolate and identify the undescribed compounds from the fruits of Cinnamomum migao and evaluate its nitric oxide inhibition potential. METHODS: 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. RESULTS: 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 IC(50) value of 4.59 μmol/L in RAW264.7 cells stimulated by LPS. CONCLUSION: The isolation of two new skeletons from the fruits part of C. migao possessed unique skeletons which have not been reported before.