Synthesis, characterization, and antibacterial activity of novel pyrazole derivatives

In this study, we report the synthesis and comprehensive characterization of a novel series of 4-((2,3,4,5substituted phenyl)diazenyl)-1-(2,5-dichlorophenyl)-3,5-dimethyl-1H-pyrazole derivatives (3a-j). The structural elucidation of these compounds was accomplished using IR spectroscopy, proton-NMR spectroscopy, carbonNMR spectroscopy, elemental analysis, and mass spectrometry. Biological evaluations demonstrated that compounds 3b, 3c, 3e, 3f, 3 g, 3h, and 3j exhibited moderate antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas fluorescens, Molecular docking studies were conducted with S. aureus dehydrosqualene synthase (PDB ID: 2ZCS), using Chloramphenicol as the reference. Notably, compounds 3a, 3d, and 3 g-3j displayed superior docking scores compared to Chloramphenicol. Additionally, Density Functional Theory (DFT) calculations using the B3LYP methodology were employed to determine the relative energies and electronic properties of compounds 3a-j. The findings of this research underscore the therapeutic potential of these pyrazole derivatives in combating bacterial infections, emphasizing the critical role of structure-activity relationship (SAR) analysis in drug development.