Synthesis, Crystal Structure, Antimicrobial Activity, and Computational Studies of Novel Pyridazine Derivatives

Abstract

Two new pyridazinone derivatives, (E)‐4‐(4‐chlorobenzyl)‐6‐styrylpyridazin‐3(2H)‐one ( 2 ) and ethyl (E)‐2‐(5‐(4‐chlorobenzyl)‐6‐oxo‐3‐styrylpyridazin‐1(6H)‐yl)acetate ( 3 ), were synthesized and characterized using FT‐IR, 1 H NMR, 13 C NMR, and single‐crystal x‐ray diffraction. Their molecular properties were further investigated using DFT calculations at the B3LYP/6‐311++G(d,p) level, including frontier molecular orbital and molecular electrostatic potential analyses. Both compounds exhibited promising antimicrobial activities, with 2 showing antibacterial effects against Enterococcus faecalis and Escherichia coli , whereas 3 displayed antifungal activity against Candida albicans and Rhodotorula mucilaginosa . Molecular docking and physicochemical analyses revealed favorable interactions with selected microbial protein targets, providing structural insights into the observed biological activities. Overall, these findings highlight the potential of the synthesized pyridazinone derivatives as promising scaffolds for further investigation as antimicrobial agents.