Synthesis, characterization, crystal structure, α‐glycosidase, and acetylcholinesterase inhibitory properties of 1,3‐disubstituted benzimidazolium salts
Selma Bal, Özlem Demirci, Betül Şen, Parham Taslımı, Aydın Aktaş, Yetkın Gök, Muhi̇tti̇n Aygün, İlhami Gülçın
Abstract
Abstract Chloro‐/fluorobenzyl‐substituted benzimidazolium salts were synthesized from the reaction of 4‐fluorobenzyl/2‐chloro‐4‐fluorobenzyl‐substituted benzimidazole and chlorinated aromatic hydrocarbons. They were characterized using various spectroscopic techniques (Fourier‐transform infrared and nuclear magnetic resonance) and elemental analysis. In addition, the crystal structures of the complexes 1a – d and 2b were determined by single‐crystal X‐ray diffraction methods. These compounds were crystallized in the triclinic crystal system with a P‐1 space group. The crystal packing of all complexes is dominated by O–H⋯Cl hydrogen bonds, which link the water molecules and chloride anions, forming a chloride–water tetrameric cluster. These synthesized salts were found to be effective inhibitors for α‐glycosidase and acetylcholinesterase (AChE), with K i values ranging from 45.77 ± 6.83 to 102.61 ± 11.56 µM for α‐glycosidase and 0.94 ± 0.14 to 10.24 ± 1.58 µM for AChE. AChE converts acetylcholine into choline and acetic acid, thus causing the return of a cholinergic neuron to its resting state. Discovering AChE and α‐glycosidase inhibitors is one of the important ways to develop new drugs for the treatment of Alzheimer's disease and diabetes.