Title: Simple analogues of natural product chelerythrine: Discovery of a novel anticholinesterase 2-phenylisoquinolin-2-ium scaffold with excellent potency against acetylcholinesterase Zhou B, Li H, Cui Z, Li D, Geng H, Gao J, Zhou L Ref: Eur Journal of Medicinal Chemistry, 200:112415, 2020 : PubMed
As simple analogues of the natural compound chelerythrine, a novel anti-cholinesterase 2-phenylisoquinolin-2-ium scaffold was designed by structure imitation. The activity evaluation led to the discovery of seven compounds with potent anti-acetylcholinesterase activity with IC50 values of =0.72 muM, superior to chelerythrine and standard drugs galantamine. Particularly, compound 8y showed the excellent dual acetylcholinesterase-butyrylcholinesterase inhibition activity, superior to rivastigmine, a dual cholinesterase inhibitor drug. Furthermore, the compounds displayed a competitive anti-acetylcholinesterase mechanism with the substrate and low cytotoxicity. Molecular docking showed that the isoquinoline moiety is embedded in a cavity surrounded by four aromatic residues of acetylcholinesterase by the pi-pi action. Structure-activity relationship showed that the p-substituents on the C-ring can dramatically improve the anti-acetylcholinesterase activity, while 8-OMe can increase the activity against the two cholinesterases simultaneously. Thus, the title compounds emerged as promising lead compounds for the development of novel cholinesterase inhibitor agents.
        
Title: 8-hydroxydihydrochelerythrine and 8-hydroxydihydrosanguinarine with a potent acetylcholinesterase inhibitory activity from Chelidonium majus L Cho KM, Yoo ID, Kim WG Ref: Biol Pharm Bull, 29:2317, 2006 : PubMed
Ethanol extract of the aerial portion of Chelidonium majus L. inhibited acetylcholinesterase (AChE) activity without a significant inhibition of butyrylcholinesterase (BuChE). Using mass spectrometry and NMR studies, three active constituents were isolated and identified: 8-hydroxydihydrochelerythrine (1), 8-hydroxydihydrosanguinarine (2), and berberine (3). Compounds 1-3 showed potent inhibitory activity against AChE, with IC50 (microM) values of 0.61-1.85. Compound 1 exhibited competitive and selective inhibition for AChE.