Metronidazole–Flavonoid Derivatives as Anti‐ Helicobacter pylori Agents with Potent Inhibitory Activity against HPE‐Induced Interleukin‐8 Production by AGS Cells

Three series of metronidazole–flavonoid derivatives were generated and evaluated for antimicrobial activity against H. pylori . Among these compounds, high anti‐ H. pylori activities were observed in isoflavones derivatives 4 – 7 , 19 , and 20 but exhibited no inhibitory activity against other sorts of bacteria and fungi, for example, Streptococcus pneumoniae, Bacillus subtilis, Escherichia coli, Pseudomonas fluorescence , and Aspergillus niger . Genistein derivative 6 with the potent activity (MIC=0.39 μg mL −1 ) was >50‐fold more than metronidazole, and comparable to the positive control amoxicillin. Additionally, compound 6 can significantly attenuate the increase in interleukin‐8 (IL‐8) levels in the AGS cells stimulated by H. pylori water extract (HPE) at concentrations of 15, 30, and 60   μmol L −1 , which did not show any effects on the cell viability.