%0 Journal Article %A Mahamoud, Abdallah %A Chevalier, Jacqueline %A Baitiche, Milad %A Adam, Elissavet %A Pagès, Jean-Marie %T An alkylaminoquinazoline restores antibiotic activity in Gram-negative resistant isolates %D 2011 %J Microbiology, %V 157 %N 2 %P 566-571 %@ 1465-2080 %R https://doi.org/10.1099/mic.0.045716-0 %K MDR, multidrug-resistant %K PAβN, phenylalanine-arginine β-naphthylamide %K EPI, efflux pump inhibitor %I Microbiology Society, %X To date, various bacterial drug efflux pump inhibitors (EPIs) have been described. They exhibit variability in their activity spectrum with respect to antibiotic structural class and bacterial species. Among the various 4-alkylaminoquinazoline derivatives synthesized and studied in this work, one molecule, 1167, increased the susceptibility of important human-pathogenic, resistant, Gram-negative bacteria towards different antibiotic classes. This 4-(3-morpholinopropylamino)-quinazoline induced an increase in the activity of chloramphenicol, nalidixic acid, norfloxacin and sparfloxacin, which are substrates of the AcrAB-TolC and MexAB-OprM efflux pumps that act in these multidrug-resistant isolates. In addition, 1167 increased the intracellular concentration of chloramphenicol in efflux pump-overproducing strains. The rate of restoration depended on the structure of the antibiotic, suggesting that different sites in the efflux pumps may be involved. A molecule exhibiting a morpholine functional group and a propyl extension of the side chain was more active. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.045716-0