Title:Synthesis and Biological Activity of Some New N1-(4-oxoquinolin-6-yl) amidrazones
VOLUME: 13 ISSUE: 2
Author(s):Salma A. Musameh, Salim S. Sabri, Mustafa M. El-Abadelah, Jalal A. Zahra, Mohammed M. Abadleh and Wolfgang Voelter
Affiliation:Chemistry Department, Faculty of Science, The University of Jordan, Amman 11942, Jordan.
Keywords:Amidrazone adducts, antibacterial activity, N1(4-oxoquinolin-6-yl)hydrazonoyl chloride, nitrile imines.
Abstract:Background: Oriented research towards discovery of new antimicrobial agents continues as several
microbes develop resistance to currently approved drugs. A selected set of N1-(1-ethyl-4-oxoquinolin-
6-yl)amidrazone-3-carboxylates incorporating N-piperazines or related congeners have been synthesized
via interaction of the particular hydrazonoyl chloride, derived from 6-amino-1-ethyl-4-oxoqinoline-3-carboxylate,
with the appropriate sec-cyclic amine.
Methods: The in vitro antibacterial activity screening of the synthetic compounds was performed against Gram negative
Escherichia coli and Gram positive Staphylococcus aureus species. The screening test was performed using Müller Hinton
Agar and Müller Hinton Broth medium. The bacterial inoculum turbidity was determined using a 0.5 McFarland standard
tube to get 105 cells/ml of bacterial concentration. Bacterial cultures were grown overnight using blood agar medium
prior to incubation with the synthetic compounds. 10 mg of each compound was dissolved in 1 ml of dimethyl sulfoxide
(DMSO).
Results: Compounds having a morpholine appendage, N-ethyl-, N-formyl-, and N-(4-methoxyphenyl)-piperazine residues
showed moderate in vitro antibacterial activity against S. aureus (MIC = 10 μg/mL). Higher activity against E. coli was
displayed by the morpholino, N-formyl-, and N-(4-methoxyphenyl)piperazine derivatives (MIC = 1 μg/mL), whilst the
compound incorporating N-(4-fluorophenyl)piperazin-1-yl grouping exhibited the highest activity with MIC = 0.1 μg/mL.
Conclusion: A selected set of quinolone-amidrazone hybrid derivatives were synthesized and tested against Gram negative
E. coli and Gram positive S. aureus species. Those hybrids incorporating morpholine, N-(formyl)piperazinyl, N-(4-
methoxyphenyl)piperazinyl and N-(4-fluoropheny)piperazinyl moieties exhibited the highest activity (MIC = 1-0.1
μg/mL).
