A Study on Antimicrobial Evaluation of Newly Synthesized Antipyrin Analogues

The antipyrinyl derived molecules are a versatile building blocker organic compounds and used in medicinal drug research. A versatile range of hybrid molecules have been synthesized by diazotization of 4-aminoantipyrin and further substituted with six different coupling components. The structures of the synthesized compounds have been confirmed by different spectral techniques. The antimicrobial activity of the synthesized molecules is investigated by agar well diffusion method against a wide range of microbial strains. The results of the antimicrobial activities of the novel synthesized molecules are statistically interpreted by dunnet post hoc test. It is found to be observed that the compound 4-[(4-Hydroxy-2-oxo-2H-chromen-3-yl)diazenyl]-1, 5-dimethyl-2-phenyl- 1H-pyrazol-3(2H)-one (4a) showed significant antimicrobial activity against S. flexneri, K. pneumonia, M. luteus, S. mitis, B. subtilis and S. aureus in comparison to standard ampicillin. The solvatochromic study of the synthesized compounds revealed that the compound 4-((2, 4-dihydroxyphenyl) diazenyl)-1, 5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one (4d) 4-((2-hydroxynaphthalen-1-yl) diazenyl)-1, 5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one (4e) showed good bathochromic shift in comparison to other solvents used. These novel synthesized azo molecules may be suggested for new establishment chemical class of antimicrobial agents and to create an opportunity in new drug discovery and medicinal research.