2,4‐Disubstituted Phenylhydrazonopyrazolone and Isoxazolone Derivatives as Antibacterial Agents: Synthesis, Preliminary Biological Evaluation and Docking Studies

A series of new 2,4‐ disubstituted phenylhydrazonopyrazolone and isoxazolones have been synthesized and evaluated for antibacterial activity. These compounds incorporated the bioactive moieties 3‐methyl isoxazolone and 3‐methyl pyrazolone. Based on the preliminary results, evaluation of these new compounds as potential antimicrobial agents revelead that four of them which incorporate the isoxazolone moiety exhibited selective antimicrobial activity against Gram‐positive bacteria with MICs for S. aureus in the 50–100 μgmL −1 range. Additionally, docking studies were performed in order to explore the possible binding poses in the MurB protein of S. aureus and the results were correlated to the antimicrobial results reported herein.