Sesquiterpene coumarins from Ferula sinkiangensis K.M.Shen and their cytotoxic activities.

Five undescribed sesquiterpene coumarins, one undescribed coumarin derivative, and twenty-five known analogues, were isolated from the resin of Ferula sinkiangensis K.M.Shen. The planar structures and relative configurations of the undescribed compounds were determined by NMR experiment and HRESIMS data. The absolute configurations were established by Electrostatic Circular Dichroism method. Among these analogues, Sinkiangenol E showed the best cytotoxic activity against HeLa cervical cancer cells. Annexin V-FITC/PI staining indicated that Sinkiangenol E induced apoptosis in HeLa cells. Cell cycle analysis showed Sinkiangenol E arrested cell cycle at G0/G1 phase. Western blot results proved that Sinkiangenol E affected apoptosis-related and cell cycle regulation-related protein expression by activating the MAPK pathway.