Exploring the Cholinesterase Inhibitory Potential of Azines Bearing a 4,4-bisdimethylaminobenzophenone Scaffold: An Experimental and Computational Approach.

Abstract

Background: Acetyl and butyrylcholinesterase are significant enzymes involved in neurological diseases, and the development of more effective inhibitors is crucial for beneficial interference.

Objective: To evaluate the cholinesterase inhibition effect of the synthetic bis-Schiff base compounds and discover the electronic properties as well as binding affinities through computational studies.

Methods: The compounds were synthesized and screened against acetyl and butyrylcholinesterase inhibitory activities in-vitro, while DFT analysis and molecular docking studies were performed for the product compounds.

Results: Seven compounds, including 2a, 2b, 2e, 2c, 2d, 2i, and 2j, exhibited excellent AChE activity, while nine compounds showed potent BChE inhibition compared to galantamine (IC50 = 156.4 ± 1.13 μM). Furthermore, the recent study on molecules 2a-e has provided valuable insights into their mechanism of action as inhibitors of the enzyme ChE, which is crucial for understanding how to regulate this enzyme's activity. Through the use of Time-Dependent Density Functional Theory (TD-DFT), the electronic characteristics of these molecules were meticulously examined, revealing that the Highest Occupied Molecular Orbitals (HOMO) are extensively delocalized across the molecular frameworks of the most active 2a-e compounds. This suggests a significant degree of electron delocalization, which is often associated with chemical reactivity and stability. In comparison to standard galantamine, these compounds demonstrate a lower electrophilicity index, which is indicative of their increased biological efficacy and lower toxicity.

Conclusion: These derivatives showed excellent AChE and BChE activities with favorable electronic properties and superior binding affinities, highlighting their potential as effective inhibitors as therapeutic agents.