Synthesis, E/Z isomerization, and antimicrobial studies of different structured novel ketone derivatives

Abstract

In this study, five novel ketones’ (k1- k5), five new hydrazones (h1-h5) and fivenew semicarbazones (s1-s5) were synthesized. The synthesized compounds were identified andtheir E/Z isomerization were studied by FT-IR, 1H-NMR, 13C-NMR, mass spectrometric andchromatographic methods. These mentioned hydrazones and semicarbazones were investigatedfor their antimicrobial activities. Seven bacterial species three fungal species were tested.Ciprofloxacin and fluconazole were used as standard compounds. The MIC values weredetermined. The relationship between structure and antimicrobial actvity was reported. It wasfound that hydrazones exhibited better activity than that of semicarbazones. Besides,acetylacetone as a diketone yielded the known 1-(2,4-dinitrophenyl)-3,5-dimethyl-1H-pyrazole(p1) which showed higher antimicrobial activity than hydrazones and semicarbazones againstKlebsiella pneumoniae ATCC 4352, Proteus mirabilis ATCC 14153, Staphylococcus epidermidisATCC 12228, Enterococcus faecalis ATCC 29212, Candida parapsilosis ATCC 22019, and Candidatropicalis ATCC 750.