Synthesis and anti-bacterial activities of some novel schiff bases derived from aminophenazone

Abstract

A series of 1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one-containing Schiff bases were synthesized, characterized and screened for their antibacterial activities. The structures of the synthesized compounds were established by spectroscopic (FT-IR, 1H-NMR, 13C-NMR, MS) and elemental analyses. The anti-bacterial activities (with MIC values) of compounds were evaluated. The anti-bacterial screening results reveal that among the six compounds screened, four compounds showed moderate to good antibacterial activity. Among the tested compounds, the most effective compounds against four bacterial strains, viz. Escherichia coli, Staphylococcus aureus, Salmonella typhimurium and Streptococcus pyogenes, are [(2-Chlorobenzylidene) amino]-1,5-dimethyl-2-phenyl- 1,2-dihydropyrazol-3-one (4) and [(1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol- 4-ylimino)methyl] benzonitrile (5) with MIC values of 6.25 μg/mL. © 2010 by the authors.