Synthesis and the antimicrobial activity of 3-(2-methyl-4-oxo-1,4-dihydroquinoline-3-yl)propanoic acids

Abstract

In order to reveal the possible regularities of the structure–activity relationship the derivatives of 3-(2-methyl-4- oxo-1,4-dihydroquinoline-3-yl)propanoic acid having various substituents in α-position of the acidic moiety of propanoic acid such as alkyl, carboxyl, acyl and acetamide substituents have been synthesized. The synthesis of the target compounds has been carried out using 3-dimethylaminomethyl-2-methyl-1,4-dihydroquinoline-4-one as a versatile alkylating reagent. Its interaction with methylene active substances allowed to obtain monoalkyldicarbonyl compounds, which further hydrolysis gave the derivatives of 3-(2-methyl-4-oxo-1,4-dihydroquinoline-3yl)propanoic acid. The structures of the compounds obtained have been confirmed by the data of 1H NMR and elemental analysis. The results of the screening performed by the agar diffusion method have shown different levels of the antimicrobial activity. For two compounds – 1,3-diethoxy-2-[(2-methyl-4-oxo-1,4-dihydroquinolin-3-yl)methyl]-1,3-dioxopropan-2-yl-carbamic acid and 3-(2-methyl-4-oxo-1,4-dihydroquinolin-3-yl)propanoic acid a moderate broad-spectrum activity has been found in the screening method. The results of the research have shown the perspectiveness of further search for novel antibacterial agents based on 4-quinolon-3-yl-propanoic acids, therefore, it is necessary to expand the range of the compounds with this scaffold.