SYNTHESIS, CHARACTERIZATION AND ANTIMICROBIAL SCREENING OF NOVEL PYRAZOLONE DERIVATIVES

Abstract

Pyrazolones, versatile nitrogen containing heterocyclic compounds displaying broad spectrum of biological and pharmacological activities. The main objective of the present study was to explore newer molecules with potent biological activity like antimicrobial activity. 5-methyl-2-(pyridin-4-ylcarbonyl)-2,4-dihydro-3H-pyrazol-3-one were synthesized by the cyclization reaction of pyridine-4-carbohydrazide and ethyl acetoacetate in the presence of  ethanol, which on treatment with different amines and formaldehyde to give mannich bases. The structure of newly synthesised compounds were characterised by IR, ¹H NMR and MASS spectral analysis. Compounds were screened for antimicrobial activity against strains of bacteria such as Staphylococcus aureus, Escherichia coli, Psuedomonus aurenginosa and fungal strains of Pencillium chrysogenum and Aspergillus niger. All the compounds exhibited good antimicrobial activity.

KEYWORDS: 5-methyl-2-(pyridin-4-ylcarbonyl)-2,4-dihydro-3H-pyrazol-3-one,Mannich bases, cyclization, Antimicrobial activity,