The emergence and spread of multidrug-resistant bacteria highlight the need for new antibacterial interventions. A screening of 24 newly synthesized dibenzoxazepines identified a small molecule compound, SW14, with potent inhibitory activity against intracellular multidrug-resistant and fluoroquinolone-resistant strains of <i>S. typhimurium</i> in macrophages and epithelial cells. Moreover, intra-macrophagic <i>Salmonella typhi</i>, <i>Yersinia enterocolitica</i>, and <i>Listeria monocytogenes</i> and methicillin-resistant <i>Staphylococcus aureus</i> are also susceptible to SW14. Overall, our findings suggest that SW14 has a broad-spectrum activity against intracellular bacteria.