Coumarins from Sarcandra glabra (Thunb.) Nakai and Acetylcholinesterase Inhibiting Activity

Nine coumarins including a pair of new enantiomers (1a/1b) and seven known compounds (2–8) were isolated from Sarcandra glabra (Thunb.) Nakai. Among them, compounds 1a and 1b were naturally occurring coumarin-phenylpropanoid conjugate enantiomers. Their structures were identified by NMR and ECD calculations. Compounds 1–8 were tested for acetylcholinesterase (AchE) inhibiting activity. The results of the enzymology experiment showed that compound 3 demonstrated obvious AchE inhibitory activity which showed the IC50 value of 1.982±0.003 μM, and the binding sites were predicted by molecular docking.