(-)-Grandiflorimine, a new dibenzopyrrocoline alkaloid with cholinesterase inhibitory activity from Illigera grandiflora.

A new dibenzopyrrocoline alkaloid, (-)-grandifloramine (1), together with five known ones, actinodaphnine (2), N-methyllaurotetanine (3), boldine (4), lindcarpine (5), and (+)-norboldine (6), were isolated from Illigera grandiflora W. W. Sm. et J. F. Jeff. The structure of 1 was identified by HRESIMS, 1D/2D NMR, and electronic circular dichroism (ECD) spectra. Compound 1 and 2 exhibited the moderate inhibitory activity against acetylcholinesterase and 3 showed moderate butyrylcholinesterase inhibitory activity. This is the first report of the chemical constituents of I. grandiflora.