An unusual sesquiterpene coumarin from the seeds of Ferula sinkiangensis

A sesquiterpene coumarin, sinkiangenorin E, consisting of a novel bicyclo[4.3.1]decane-type sesquiterpene system, was isolated from the seeds of Ferula sinkiangensis. The structure of sinkiangenorin E including the relative stereochemistry and the absolute configuration was elucidated on the basis of spectroscopic data. The new compound showed cytotoxic activity against AGS cells (IC50, 12.7 μM) and inhibiting effect against influenza A H1N1 (IC50, 4.0 μM), which provided important clues for the study on the bioactivities of this type of sesquiterpene coumarins.