Trifluoromethylpyridine 1,3,4-Oxadiazole Derivatives: Emerging Scaffolds as Bacterial Agents

Abstract

A new class of trifluoromethylpyridine 1,3,4-oxadiazole derivatives (<b>6a</b>-<b>6v</b>) was obtained, and their antibacterial activities were evaluated. Some of them exhibited good activity, particularly <b>6a,</b> which had the highest in vitro activity against <i>Ralstonia solanacearum</i> (<i>R. solanacearum</i>) and <i>Xanthomonas axonopodis</i> pv. <i>citri</i> (<i>Xac</i>). The half-maximal effective concentrations (EC₅₀) were 26.2 and 10.11 μg/mL, respectively, which were lower than those of commercial thiodiazole copper (97.2 and 35.3 μg/mL, respectively). Furthermore, <b>6q</b> showed much higher activity against <i>Xanthomonas oryzae</i> pv. <i>oryzae</i> (<i>Xoo</i>) with an EC₅₀ value of 7.2 μg/mL; this was superior to bismerthiazol (57.2 μg/mL). Collectively, our findings provide a foundation for the development of trifluoromethylpyridine 1,3,4-oxadiazole derivatives.