Cholinesterase Inhibition and Molecular Docking Studies of Sesquiterpene Coumarin Ethers from Heptaptera cilicica

Five sesquiterpene coumarin ethers: umbelliprenin, umbelliprenin-10',11'-monoepoxide, conferone, mogoltacin and feselol were isolated from the fruits of Heptaptera cilicica. Their structures were identified by means of spectroscopic methods. AChE and BuChE inhibitory activities of the compounds were determined by molecular docking method which were confirmed by in vitro experiments. According to molecular docking results, total score of feselol and umbelliprenin were 5.69 and 3.23 kcal/mol against acetylcholinesterase, respectively. Total score for butyrylcholinesterase inhibitory effect of them were 2.76 and 4.99 kcal/mol, respectively. Feselol and umbelliprenin exhibited significantly high inhibitory potency against acetylcholinesterase (IC 50 = 1.26 ± 0.01 and 5.86 ± 0.03 μM, respectively) and butyrylcholinesterase (IC 50 = 9.98 ± 0.24 and 1.10 ± 0.19 μM, respectively). This is the first report of isolation of natural bioactives obtained from the chloroform extract of Heptaptera cilicica fruits with anticholinesterase activity.