Synthesis of novel pyrimidine and pyrazole hybrids as potential antimicrobial agents

Abstract

As a part of the ongoing endeavours in the exploration of novel antimicrobial agents, herein is reported a novel synthesis of hybrid molecules <span style="mso-bidi-font-weight: bold">5-(4-arylidene-3-methyl-5-oxo-4,5-dihydro-1<i>H</i>-pyrazole-1-carbonyl)-4-(4-hydroxyphenyl)-6-methyl-3,4-dihydropyrimidin-2(1<i>H</i>)-ones <b style="mso-bidi-font-weight:normal">4 </b>by combining pyrimidine and pyrazole scaffolds having diverse pharmacological activities. The characterization of these newly synthesized compounds has been carried out by IR, ¹H and ¹³C NMR and mass spectroscopy. All the synthesized compounds have been evaluated for their <i>in vitro </i>antimicrobial activity against Gram-positive bacteria (<i>Staphylococcus aureus</i> and <i>Streptococcus pyogenes</i>), Gram-negative bacteria (<i>Escherichia coli </i>and <i>Pseudomonas aeruginosa</i>) and fungi (<i>Candida albicans, Aspergillus niger </i>and <i>Aspergillus clavatus</i>) using serial broth dilution method. Among all these synthesized compounds <b>4l</b> and <b>4d </b>have emerged as highly potent molecules with 12.5 μg/mL potency against <i>Pseudomonas aeruginosa </i>and <i>Aspergillus niger</i> respectively.

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