Synthesis and biological evaluation of some pyrazolylpyrazolines as anti-inflammatory–antimicrobial agents

A new series of pyrazolylpyrazolines (5a–k) was synthesized by the reaction of appropriate chalcones (3a–k) with 4-hydrazinobenzenesulfonamide hydrochloride (4) in ethanol. All the newly synthesized target compounds (5a–k) were screened for their anti-inflammatory activity using carrageenan-induced rat paw edema assay. Compounds 5g and 5j showed pronounced anti-inflammatory activity comparable to the reference standard nimesulide, whereas, compounds 5b, 5d and 5h displayed good anti-inflammatory activity. Additionally, the synthesized compounds were evaluated for their in vitro antimicrobial activity against two Gram-positive bacteria and two Gram-negative bacteria. Four compounds 5c, 5h–5j showed good broad spectrum activity against all the tested Gram-positive and Gram-negative bacterial strains. Compound 5j could be identified as the most biologically active member within this study with an interesting dual anti-inflammatory and antibacterial profile.

A series of pyrazolylpyrazolines with vicinal diaryl substitution pattern on the pyrazole as well as pyrazoline nucleus was synthesized. One of the compounds showed interesting dual anti-inflammatory and antibacterial profile.Figure optionsDownload as PowerPoint slide