Submit Manuscript  

Article Details

Synthesis of Novel Bis-pyrazole Derivatives as Antimicrobial Agents


Zeinab A. Muhammad, Fatimah Alshehrei, Mohie E. M. Zayed, Thoraya A. Farghaly* and Magda A. Abdallah   Pages 1 - 15 ( 15 )


Background: bis-heterocycles especially those contain pyrazole moiety displayed much better antibacterial activity than mono heterocycles.

Objective: we interested herein to synthesis a series of new bis-pyrazoles and investigate its antimicrobial agents.

Method: A novel series of bis-pyrazole derivatives has been synthesized in good yield by coupling reaction of cyanoacetic acid {4-[(2-cyano-acetyl)-hydrazonomethyl]-benzylidene}-hydrazide with a number of diazonium salts of aromatic amines in DMF in the presence of NaOH. Refluxing of the produced hydrazones with hydrazine-hydrate in ethanolic solution afforded the respective bis-pyrazoles. On the other hand, reaction of bis(cyanoacetic acid hydrazide) derivative with a diversity of hydrazonoyl chlorides in dioxane under reflux in the being of bis-pyrazoles.

Results: All the structures of all products were discussed and assigned via both all possible spectral data as well as the elemental analysis. In addition, the results of the antimicrobial activity examination of selected derivatives revealed a high strength of some tested compounds compared to standard bactericides and fungicides utilized. Molecular docking of the newly synthesized compounds into the Enoyl ACP reductase active site supported the in vitro antimicrobial activity. All the compounds could fit in the enzyme binding pocket with significant binding affinities (-7.040 to -9.141 Kcal/mol).

Conclusion: The good results of the antimicrobial examination of the new synthesized bis-pyrazoles is the considerable evidence of the importance of bis-heterocyclic compounds which encourage us to continue to design and synthesis a novel series with potent biological activity in the future.


Antimicrobial agents, bis-pyrazoles, hydrazonoyl halides, coupling reaction.


National Organization for Drug Control and Research (NODCAR), P.O. Box 29, Cairo, Department of Biology, Faculty of Applied Science, Umm Al-Qura University, Makkah 24382, Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah B.O.208203, Department of Chemistry, Faculty of Science, Cairo University, Giza, 12613, Department of Chemistry, Faculty of Science, Cairo University, Giza, 12613

Read Full-Text article