Synthesis of some novel 2-substituted benzothiazole derivatives containing benzylamine moiety as monoamine oxidase inhibitory agents

Abstract

In the present work, 12 new 2-(5-substituted-benzothiazol-2-ylsulfanyl)-N-(substitutedbenzyl)-N-(4-substitutedphenyl) acetamide derivatives (4a–l) was designed and synthesized. The structures of the synthesized compounds were clarified using Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H-NMR), carbon-13 nuclear magnetic resonance (13C-NMR) and high-resolution mass spectrometry (HRMS) spectral data. Purity of synthesized compounds was checked by high-performance liquid chromatography (HPLC) analyses and purity ratio was found between 96.5–99.9%. The inhibitory activity of the compounds against MAO-A and MAO-B enzymes was evaluated by using in vitro flurometric method in which kynuramine was used as a substrate. Most of the compounds exhibited more selective inhibitory activity towards monoamine oxidase B (MAO-B) than monoamine oxidase A (MAO-A). Compound 4h was determined as the most potent compound against both enzyme types. The MAO-B enzyme kinetic of the compound 4h was studied and nature of MAO-B inhibition, caused by this compound, was investigated. The graphical analysis of steady-state inhibition data indicated that compound 4h is a mixed type inhibitor. Theoretical calculation of absorption, distribution, metabolism, excretion (ADME) properties for the synthesized compounds was also carried out and observed data supported the potential of compound 4h.