Substituted quinolinones. Part 22. In vitro antimicrobial evaluation of some 4-hydroxy-1-methyl- 3-pyrazolinylquinolin-2(1H)-ones as useful antibiotic intermediates

Abstract

Thirty derivatives of 3-pyrazolylquinolinone, in three different types; enaminones 1a–j, enones 2a–j, and hydrazonones 3a–j, have been investigated for their in vitro antimicrobial activity. The tested compounds have been screened against four chosen microorganisms, two bacteria strains (Staphylococcus aureus, as Gram-positive bacterium, and Escherichia coli, as Gram-negative bacterium), and two fungi strains (Aspergillus flavus and Candida albicans). Disc plate and serial dilutions techniques were used to evaluate and determine the antimicrobial activity and minimum inhibition concentration of the tested compounds. The results revealed that the enaminone derivatives 1a–j have desirable antimicrobial activity against both bacteria and fungi groups, and they are promising useful antibiotic intermediates.