Synthesis, crystal structure, antimicrobial and computational investigations of two pyridazinone derivatives

In this study, two new pyridazine derivatives were synthesized and characterized using FT-IR, 1H NMR, 13C NMR, ESI-HRMS, and single-crystal X-ray diffraction. These compounds were designed and investigated as potential antimicrobial agents, with particular interest in their possible application against clinically relevant bacterial and fungal strains. To support this objective, a combined experimental and computational approach was employed, including Hirshfeld surface analysis, energy framework calculations, crystal void analysis, DFT-B3LYP calculations, molecular docking, and in silico ADMET predictions. The antimicrobial potential of the synthesized compounds was evaluated against a panel of twelve microbial strains, including Gram-positive bacteria, Gram-negative bacteria, and yeasts. The findings suggest that pyridazine-based compounds, especially compound 4, may represent promising candidates for the development of new antibacterial and antifungal agents. Their activity against resistant or clinically important microorganisms highlights their potential relevance in antimicrobial drug discovery.