Herein, we report on identification of a new quipazine derivative—compound 9c (N-(3-chlorobenzyl)-2-(piperazin-1-yl)quinolin-4-amine), which displayed antibacterial properties (MIC range 2–4 μg/mL) against H. pylori CagA-positive reference strains associated with an increased risk of gastric cancer, including metronidazole-resistant ATCC 43504, clarithromycin-resistant ATCC 700684 and susceptible J99 strain, as well as clinical, multidrug-resistant isolate (3CML, resistant to clarithromycin, metronidazole and levofloxacin). Here, S100A8 is linked to gastric cancer.