Synthesis, characterization of novel mannich bases and their acetylcholinesterase and glutathione S-transferase inhibitory properties: An in vitro and in silico mechanism research

Abstract

In this study, 4-((3,4-Dimethoxybenzylidene)amino)-5-alkyl(aryl)-2,4-dihydro-3H-1,2,4-triazol-3-ones (4a-g) reacted with formaldehyde and 2,6-dimethylmorpholine to obtain seven novel potential biologically active 4-((3,4-Dimethoxybenzylidene)amino)-2-((2,6-dimethylmorpholino)methyl)-5-alkyl(aryl)-2,4-dihydro-3H-1,2,4-triazol-3-ones (5a-g). The structures (5a-g) of newly synthesized compounds were characterized using FT-IR, ¹H-NMR, and ¹³C-NMR spectral data. The synthesized compounds (5a-g) were investigated for it is in vitro enzyme inhibition properties. Results demonstrated that the newly synthesized compounds had valuable enzyme inhibition activities against acetylcholinesterase (AChE) and glutathione S-transferase (GST) enzymes. Their Ki values were calculated in the range of 0.96 ± 0.0557- 9.7967 ± 5.3105 µM, while their IC₅₀ values were calculated in the range of 1.333–3.551 µM. Tacrine was used for AChE, Ethacrynic acid was used for GST as positive standard. Molecular docking studies revealed that compound 5b binds to AChE and compound 5f binds to GST with high affinity (−10.2 and −9.1 kcal/mol) in protein-ligand complexes. The stability of the ligand-protein complexes was confirmed by 100 ns molecular dynamics simulations.