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Two-dimensional view of the main interactions carried out by the aporphine alkaloids in the catalytic site of the enzymes AChE and BChE. [Display omitted] • Annona crassiflora is an interesting source of aporphine alkaloids. • The alkaloids were isolated from Annona crassiflora fruit peels. • Structural elucidation were made by spectrometric and spectroscopic analysis. • Anticholinesterase activity of the alkaloids were compared with galantamine. • In silico evaluation were made to predict the binding mode of the ligands. Annona crassiflora Mart. is an endemic plant from Brazilian Cerrado (savanna) biome, commonly employed in traditional medicine to treat wounds, diarrhea, and scalp infections. The pulp of the fruits is edible and has a characteristic taste, being employed to prepare sweets like jam, cakes, and ice cream by the people who live in the region of the Cerrado, although the peels are discarded. In this way, the A. crassiflora fruit peels ethanol extract was prepared and subjected to liquid–liquid extraction, which yielded the alkaloidal fraction (CH 2 Cl 2). Subjected to high-performance liquid chromatography separations, this fraction allowed the purification of the aporphine alkaloids stephalagine (1), liriodenine (2), and atherospermidine (3), that were structurally characterized by high-resolution mass spectrometry with electrospray ionization, and nuclear magnetic resonance spectroscopy analyses. Aporphine alkaloids are recognized for their acetylcholinesterase (AChE) inhibitory activity, an important target in Alzheimer's disease therapy. Thus, the ethanol extract, alkaloidal fraction, and compounds 1 , 2 , and 3 were evaluated for acetyl- and butyrylcholinesterase (BChE) inhibitory activities. Compound 1 (IC 50 104.2 µmol L–1) exhibited better BChE inhibitory activity than the standard compound galanthamine (IC 50 162.7 µmol L–1), while 2 had a comparable result (and IC 50 167.3 µmol L–1). Furthermore, molecular docking was performed to predict the compound's binding mode to the human AChE at a molecular level. Semiempirical calculation results show that the enthalpy interaction energy (ΔH int) between AChE and BChE active sites and all ligands were favorable for both enzymes, with the ligands interacting even more strongly with AChE, corroborating with IC 50 results. [ABSTRACT FROM AUTHOR]