Abstract

SYNTHESIS AND ANTIMICROBIAL ACTIVITY EVALUATION OF SOME (3E)-2,6-DIARYL-N-PYRIDINYL-4,5-DIHYDROPYRIDAZIN- 3(2H)-IMINES

*Mohd. Imran

Abstract

Some (3E)-2,6-diaryl-N-pyridinyl-4,5-dihydropyridazin-3(2H)-imines were prepared by the reaction of 2-(aryl)-6-phenyl-4,5- dihydropyridazin-3(2H)-ones with appropriate pyridinyl amine using acetic acid as a solvent. The structures of the representative compounds were confirmed on the basis of their FTIR, 1H-NMR, and 13C-NMR. These compounds were evaluated for their antimicrobial activity by the cup plate method against two Gram positive bacteria, namely, Staphylococcus aureus and Bacillus subtilis; three Gram negative bacteria, namely, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumonia; and one fungus, Candida albicans. These compounds showed mild to moderate antimicrobial activity with respect to the standard drugs Ofloxacin and Ketoconazole. However, it has been identified that the presence of 2-pyridinyl group is an essential requirement in the chemical structure of these types of compounds to show better antimicrobial activity. It is also believed that the replacement of the phenyl, 4-nitropheny, and 2,4-dinitrophenyl groups at position 2 of the pyridazinone ring with other similar isosteres or bioisosteres along with the presence of 2-pyridinyl moiety may provide better antimicrobial agents.

Keywords: Pyridazinone, 2-Pyridinyl, Antibacterial activity, Antifungal activity, Structure activity relationship.