Synthesis and evaluation of new pyrazoline‐thiazole derivatives as monoamine oxidase inhibitors

Abstract

A novel series of 1,3,5‐trisubstituted‐2‐pyrazoline derivatives (4a‐4k) was synthesized and their chemical structures characterized by 1H NMR, 13C NMR, and mass spectroscopy. These compounds were evaluated as inhibitors for of type A and type B monoamine oxidase (MAO) enzymes. The most common inhibitors of MAO enzymes used to treat depression and anxiety such as selegiline and moclobemide drugs were used as reference agents. A result of biological evaluation of these compounds revealed compounds 4c, 4d, and 4ı as potent and selective MAO A inhibitors. The most active compound 4ı, which is 2,4‐dimethoxy at phenyl ring, showed strong inhibitory activity at MAO A (IC50 of 0.0445 ± 0.0018μM). Furthermore, compounds 4c and 4d showed significant inhibition profile on MAO A with the IC50 values 0.1423 ± 0.0051μM and 0.2148 ± 0.0067μM, respectively.

Development in the Synthesis of Bioactive Thiazole-Based Heterocyclic Hybrids Utilizing Phenacyl Bromide

“…(Figure 18). Acar Çevik et al 71 The introduction of a methoxy group in these derivatives was observed to enhance inhibitory activity and selectivity for MAO A enzymes, which play a crucial role in the metabolism of neurotransmitters such as serotonin, norepinephrine, and dopamine in the central nervous system (Scheme 17).…”

“…Acar Çevik et al 71 have detailed the synthetic route for the preparation of 2-(3-(4-(4-benzylpiperidin-yl)phenyl)-5-phenyl-4,5-dihydro-1 H -pyrazol-1-yl)-4-(substitutedphenyl)-thiazole conjugates ( 45a – 45k ). This involved the utilization of phenacyl bromide 43 and 3-(4-(4-benzylpiperidin-1-yl)phenyl)-5-phenyl-4,5-dihydro-1 H -pyrazone-1-carbothioamides 44 through a refluxing reaction mixture on a water bath for a duration of 3 h in ethanol, resulting in moderate yields.…”