Design and synthesis of some new pyrazolyl-pyrazolines as potential anti-inflammatory, analgesic and antibacterial agents.

In the present study, an efficient synthesis of some new substituted pyrazoline derivatives linked to a substituted pyrazole scaffold was performed by a multistep reaction sequences and compounds were screened for their anti-inflammatory, analgesic and antibacterial activities. The preliminary results revealed that the N-acylated (5e, 5h) and nitro substituted N-phenyl (6f) pyrazolyl-pyrazolines derivatives exhibited a very promising anti-inflammatory activity whereas 5h, 6f were interesting analgesic agents. The compounds with halo substituted phenyl group at C-3 of the pyrazoline ring (4a, 5g, 5h, 6a and 6b) were found to be active against clinical bacterial pathogens with MIC in the range of 0.2-0.4 mg/mL. Compound containing N-propionyl pyrazolyl-pyrazoline (5h) could be identified as the most active member within this study with a dual anti-inflammatory and antibacterial profile. Taken together, this study has led to the development of promising compounds.