Antimicrobial O-Alkyl Derivatives of Naringenin and Their Oximes Against Multidrug-Resistant Bacteria

Abstract

New antimicrobial agents are needed to address infections caused by multidrug-resistant bacteria. Here, we are reporting novel <i>O</i>-alkyl derivatives of naringenin and their oximes, including novel compounds with a naringenin core and <i>O</i>-hexyl chains, showing activity against clinical strains of clarithromycin-resistant <i>Helicobacter pylori</i>, vancomycin-resistant <i>Enterococcus faecalis</i>, methicillin-resistant <i>Staphylococcus aureus</i>, and beta-lactam-resistant <i>Acinetobacter baumannii</i> and <i>Klebsiella pneumoniae.</i> The minimum inhibitory concentrations (MICs), which provide a quantitative measure of antimicrobial activity, were in the low microgram range for the selected compounds. Checkerboard assays for the most active compounds in combination with antibiotics revealed interactions that varied from synergistic to neutral.