RESUMO
There has been a substantial research effort to design multi-target ligands for the treatment of Alzheimer's disease (AD), an approach that is moved by the knowledge that AD is a complex and multifactorial disease affecting many linked to pathological pathways. Accordingly, we have devoted efforts to develop multi-target ligands based on the chromone scaffold. As a result, a small library of chromone derivatives was synthesized and screened towards human cholinesterases and monoamine oxidases. Compounds 2-(dimethylamino)ethyl (E)-3-(4-oxo-2-(p-methylphenlcarbamoyl)-4H-chromen-6-yl)acrylate (9a) and 2-(dimethylamino)ethyl (E)-3-(4-oxo-3-(phenylcarbamoyl)-4H-chromen-6-yl)acrylate (23a) were identified as the most promising multi-target inhibitors of the series. Compound 9a acted as a potent, selective and bifunctional AChEI (IC50â¯=â¯0.21⯵M, Kiâ¯=â¯0.19⯵M) and displayed dual hMAO inhibitory activity (hMAO-A IC50â¯=â¯0.94⯵M, Kiâ¯=â¯0.057⯵M and hMAO-B IC50â¯=â¯3.81⯵M, Kiâ¯=â¯0.48⯵M). Compound 23a acted as a selective IMAO-B (IC50â¯=â¯0.63⯵M, Kiâ¯=â¯0.34⯵M) while still displaying hChE inhibitory and bifunctional activity in the low micromolar range. Overall, these two compounds stand out as reversible multi-target inhibitors with favourable permeability, toxicological and drug-like profiles, thus being valid candidates for subsequent optimization and pre-clinical studies.