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

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).