SYNTHESIS AND EVALUATION OF ANTIMICROBIAL ACTIVITY OF PHENYLPYRAZOLE DERIVATIVES

Abstract

The narrow antibacterial spectrum of phenylthiazole antibiotics was expanded by replacing the central thiazole with a pyrazole ring while maintaining its other pharmacophoric features. The most promising derivative, compound 10, was moderate potent against MDR-Gram-positive clinical isolates, including vancomycin- and linezolid-resistant MRSA, with a minimum inhibitory concentration (MIC) value 8 g/mL. Moreover, compound 10 was promising against highly pathogenic carbapenem-resistant strains, such as Acinetobacter baumannii, Klebsiella pneumoniae and E. coli. In addition to the notable biofilm inhibition activity, compound 10 outperformed both vancomycin and kanamycin in reducing the intracellular burden of both Gram-positive and Gram-negative pathogenic bacteria. Compound 10 cleared 90% of intracellular MRSA and 98% of Salmonella enteritidis at 2× the MIC.