Design, Synthesis, Docking Study of Pyrazolohydrazinopyrimidin-4-one Derivatives and Their Application as Antimicrobials.

New series of pyrazoles 4a-c and pyrazolopyrimidines 5a-f had been constructed. The newly synthesized compounds were assessed for their antimicrobial activity towards E. coli and P. aeruginosa (gram -ve bacteria), B. subtilis and S. aureus (gram +ve bacteria) and A. flavus and C. albicans (representative of fungi). The pyrazolylpyrimidine-2,4-dione derivative 5b is the most active candidate against B. subtilis (MIC=60 µg/mL) and P. aeruginosa (MIC=45 µg/mL). Regarding antifungal potential, compound 5f was the most effective against A. flavus (MIC=33 µg/mL). Similarly, compound 5c displayed strong antifungal activity towards C. Albicans (MIC=36 µg/mL) in reference to amphotericin B (MIC=60 µg/mL). Finally, the novel compounds had been docked inside dihydropteroate synthase (DHPS) to suggest the binding mode of these compounds.