Synthesis and biological evaluation of 2′-Aminochalcone: A multi-target approach to find drug candidates to treat Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative process that compromises cognitive functions. The physiopathology of AD is multifactorial and is mainly supported by the cholinergic and amyloid hypotheses, which allows the identification the fundamental role of some markers, such as the enzymes acetylcholinesterase (AChE) and beta-secretase (BACE-1), and the beta-amyloid peptide (A beta). In this work, we prepared a series of chalcones and 2'-aminochalcones, which were tested against AChE and BACE-1 enzymes and on the aggregation of A beta. All compounds inhibited AChE activity with different potencies. We have found that the majority of chalcones having the amino group are able to inhibit BACE-1, which was not observed for chalcones without this group. The most active compound is the one derived from 2,3-dichlorobenzaldeyde, having an IC50, value of 2.71 mu M. A molecular docking study supported this result, showing a good interaction of the amino group with aspartic acid residues of the catalytic diade of BACE-1. Thioflavin-T fluorescence emission is reduced in 30 - 40%, when A beta(42) is incubated in the presence of some chalcones under aggregation conditions. In vitro cytotoxicity and in silico prediction of pharmacokinetic properties were also conducted in this study.