A new series of thiazolyl pyrazoline derivatives linked to benzo[1,3]dioxole moiety: Synthesis and evaluation of antimicrobial and anti-proliferative activities

Abstract

2-(5-(Benzo[d][1,3]dioxol-5-yl)-3-(naphthalen-1-yl)-4,5-dihydro-1H-pyrazol-1-yl)-4-(4-substituted phenyl)thiazole (7) and thiazole derivatives (9) were synthesized via reaction of 4,5-dihydro-1H-pyrazoles (5a,b) with substituted phenacyl bromide and a number of α-halo-compounds respectively. Also, (E)-2-(5-(benzo[d][1,3]dioxol-5-yl)-3-(naphthalen-1-yl)-4,5 dihydro-1H-pyrazol-1-yl)-4-methyl-5-(substituted phenyldiazenyl)thiazole (11) were prepared through reactions of carbothioamide (5a,b) with hydrazonoyl halides. In addition, thioamides (5a–b) were used as starting materials for preparation of thiazoles (12a–b) and benzylidene thiazoles (13a–b). Most of synthesized compounds show interesting biological properties as antimicrobial and antiproliferative activities, the results of minimum inhibitory concentration showed that pyrazole derivative 7c (MIC: 0.23 mg/mL) showed better results when compared with 11c and 12a (MIC: 0.1–0.125 mg/mL) as obtained from their MIC values. On the other hand, 2-(5-(benzo[d][1,3]dioxol-5-yl)-3-(naphthalen-2-yl)-4,5-dihydro-1H-pyrazol-1-yl)-4-(4-chlorophenyl) thiazole (7c) can be considered as the most promising anti-proliferative agent against HCT-116 cancer cells owing to its notable inhibitory effect on HCT-116 cells with an IC50 value of 6.19 µM.