Selective Inhibition of the Periodontal Pathogen Porphyromonas gingivalis by Third-Generation Zafirlukast Derivatives

Periodontal diseases are inflammatory diseases triggered by pathogenic oral bacterial species, such as Porphyr-omonas gingivalis. Zafirlukast (ZAF) has displayed antibacterial activity against P. gingivalis. Herein, we report the design, synthesis, and selective antibacterial activity of 14 novel third-generation ZAF derivatives. Two second-generation ZAF derivatives were tested as they were not previously tested against P. gingivalis ATCC 33277. Most third-generation derivatives displayed superior/selective antibacterial activity against P. gingivalis compared to ZAF and its second-generation derivatives. The compounds displayed bactericidal activity against P. gingivalis, inhibited biofilm growth, displayed no hemolytic activity, and displayed less cytotoxicity against mammalian cells than ZAF. The superior/selective antibacterial activity of ZAF derivatives against P. gingivalis, increased safety profile, and inhibition of biofilm growth compared to ZAF indicate that the compounds, especially 21a, 21b, and 24g, show promise as antibacterial agents for future studies to test their potential for preventing and treating P. gingivalis-induced periodontal diseases.