Sesquiterpenoids and triterpenoids from Secamone lanceolata blume with inhibitory effects on nitric oxide production

Abstract Five previously undescribed sequiterpenoids, including three guaiane sesquiterpenoids secamonol A ( 2 ), secamonester ( 3 ), secamonether ( 4 ), and one elemanolide sequiterpenoid secamonol B ( 7 ), and one eudesmane sesquiterpenoid secamonol C ( 8 ) along with nine known compounds were isolated from Secamone lanceolata Blume. Their structures and absolute configurations were established by analyzing of NMR, CD, MS spectrum and single-crystal X-ray diffraction, as well as comparing with the literatures. Compounds 1 and 4 – 8 exhibited potential inhibition activities of NO production with IC 50 values in the range of 27.9–57.5 μM with no obvious cytotoxicities even at the high concentration (100 μM). Whereas, compound 3 showed significant cytotoxicity with CC 50 value of 5.6 μM against macrophages RAW264.7 Cells.