Searching for novel antimicrobial agents among hydrazide-hydrazones of 4-iodosalicylic acid

Abstract

Searching for novel antimicrobial agents is up to day topic for many group of researchers due to the fact that each year the number of bacterial strains resistant to currently used medicines increases. Special attention in the scientific literature among various groups of bioactive organic compounds is focused on the antimicrobial activity of hydrazide-hydrazones. Due to this fact presented study is focused on the design, synthesis and in vitro antimicrobial properties of novel hydrazide-hydrazones of 4-iodosalicylic acid. Target compounds were synthesized by the condensation reaction of the hydrazide of 4-iodosalicylic acid with substituted (hetero)aromatic aldehydes. Chemical structure of obtained molecules was confirmed by spectral methods (¹H NMR and ¹³C NMR). Bioactivity screening results revealed interesting antimicrobial properties of tested compounds against reference Gram-positive bacteria and fungi belonging to Candida spp. Especially, hydrazide-hydrazones 3-5 showed very strong or strong bactericidal effect towards some cocci and bacilli (MIC = 7.81-15.62 µg/mL).

Keywords: 4-iodosalicylic acid derivatives; Antimicrobial activity screening; Hydrazide-hydrazones; Spectral analysis.