Monoterpene esters and aporphine alkaloids from Illigera aromatica with inhibitory effects against cholinesterase and NO production in LPS-stimulated RAW264.7 macrophages

Three new monoterpene phenylpropionic acid esters, illigerates A–C ( 1 – 3 ), and one new aporphine alkaloid, illigeranine ( 4 ), as well as four known ones, actinodaphnine ( 5 ), nordicentrine ( 6 ), 8-hydroxy carvacrol ( 7 ), and 3-hydroxy- α ,4-dimethyl styrene ( 8 ), were isolated from the tubers of Illigera aromatica. The structures of 1 – 4 were identified by HRESIMS, 1D and 2D NMR, and electronic circular dichroism spectra. Compound 1 potently inhibited NO production in LPS-stimulated RAW264.7 cells with an IC 50 value of 18.71 ± 0.85 μM; compound 1 , 3 , and 4 showed moderate butyrylcholinesterase inhibitory activities with the IC 50 values of 46.86 ± 0.65, 53.51 ± 0.71, and 31.62 ± 1.15 μM, respectively. Compound 4 showed weak AChE inhibitory activity with an IC 50 value of 81.69 ± 2.07 μM, and compounds 5 and 6 possessed moderate AChE inhibitory activities with the IC 50 values of 47.74 ± 1.66 and 40.28 ± 2.73 μM, respectively. This paper provides a chemical structure and bioactive foundation for using I. aromatica as an herbal medicine.