Synthesis and biological activity of novel amidrazones incorporating 5-nitroimidazole, ciprofloxacin, and 7-chloro-4-piperazinylquinoline

Abstract Series of new amidrazones Ia-c, IIa-c, and IIIc, incorporating 5-nitroimidazole (a), ciprofloxacin (b), and 7-chloro-4-piperazinylquinoline (c) moieties, were synthesized by reacting hydrazonoyl chlorides I-III, derived from 4-fluoroaniline and 4-chloroaniline with the proper amine, in the presence of triethylamine. Structures of the prepared compounds were confirmed by ¹H NMR, ¹³C NMR, and ESI-HRMS spectral data. The antitumor, antibacterial, and antiparasitic activities of the newly synthesized compounds were evaluated. Compounds Ic and IIc exhibited strong anticancer activity against all tested cancer cell lines. In addition, compounds Ia and IIa displayed stronger antimicrobial potency than metronidazole against microaerophilic bacteria. Compounds IIa, IIIc, and IIc, exhibited remarkable antigiardial activity and were found to be more active than metronidazole with IC₅₀ of 5.6, 5.9, and 6.8 μg/mL, respectively. Compounds Ia, Ib, and Ic also exhibited antigiardial activity with similar IC₅₀ values compared to the reference drug metronidazole (IC₅₀ = 6.9 μg/mL). On the other hand, compounds Ia, Ib, and IIa exhibited significant antitrichomonal activity and found to be more active than metronidazole with IC₅₀ of 3.79, 4.6, and 5.1 μg/mL, respectively, compared to the reference drug metronidazole (8.79 μg/mL).