Synthesis and evaluation of human monoamine oxidase inhibitory activities of some 3,5-diaryl-N-substituted-4,5-dihydro-1H-pyrazole-1-carbothioamide derivatives

Abstract

Sixteen 3-aryl-5-(4-fluorophenyl)-N-substituted-4,5-dihydro-1H-pyrazole-1-carbothioamide derivatives were synthesized and their structure were identified by UV, IR, (1) H NMR, mass spectra, and microanalyses. The compounds were evaluated in vitro for their human monoamine oxidase (hMAO) inhibitory activities and their MAO-A and -B selectivity. All the compounds were found to potently inhibit MAO-A isoforms. 5-(4-Fluorophenyl)-3-(4-methoxyphenyl)-N-methyl-4,5-dihydro-1H-pyrazole-1-carbothioamide (1.0 × 10(-3) µM) was found to inhibit hMAO-A most selectively and potently. The binding mode of 5-(4-fluorophenyl)-3-(4-methoxyphenyl)-N-methyl-4,5-dihydro-1H-pyrazole-1-carbothioamide to hMAO-A was also predicted using docking studies.