Discovery of Hydrazone Scaffolds as Potent and Selective Multitarget‐Directed Ligands for the Treatment of Neurodegenerative Disorders.

In the current work, new and diverse hydrazone derivatives were designed and synthesized through a facile and multistep synthetic approach. The chemical structures were elucidated by various spectroscopic techniques. In vitro bioactivity analysis demonstrated selective and potent inhibitory potential of hydrazone derivatives against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes. (E)‐3‐chloro‐N′‐(1‐phenylethylidene) benzohydrazide remarkably emerged as a lead candidate exhibiting potent and selective inhibition of AChE with an IC50 value of 0.63±0.01 μM whereas (E)‐3‐chloro‐N′‐(1‐(thiophen‐2‐yl)ethylidene)benzohydrazide delivered the strong potency and selective inhibition towards monoamine oxidase A with an IC50 value of 0.89±0.04 μM. Moreover, (E)‐3‐chloro‐N′‐(1‐(4‐methylthiophen‐2‐yl)ethylidene)benzohydrazide (IC50=2.06±0.01 μM) and (E)‐3‐chloro‐N′‐(1‐(5‐chlorothiophen‐2‐yl)ethylidene)benzohydrazide (IC50=2.06±0.05 μM) were identified as lead inhibitors of monoamine oxidase B. Molecular docking studies of potent and selective inhibitors exhibited various important interactions with amino acid residues in the active pocket of both enzymes, thus strengthening our in vitro results. The kinetics analysis of the most potent compound against AChE revealed non‐competitive mode of inhibition, whereas against monoamine oxidase (A & B), the corresponding lead inhibitors exhibited mixed type of inhibition. Molecular dynamics simulations were also performed to investigate the energetically stable complex formation ability of potent compounds with the target protein. Finally, the results of in silico pharmacokinetic properties showed that the potent compounds have promising pharmacological effects that follow all the parameters of drug‐likeness and could serve as effective drug candidates for future investigations. [ABSTRACT FROM AUTHOR]