Discovery of the trifluoromethyloxadiazoles—a new class of fungicides with a novel mode-of-action

While screening for new chemical classes to control fungal diseases, BASF identified the trifluoromethyloxadiazoles (TFMOs) as a promising cluster. These compounds inhibit fungal class II histone deacetylases (HDACs) and are able to efficiently control plant diseases such as Asian soybean rust and brown rust on wheat caused by phytopathogens. Besides the TFMOs, two further known HDAC inhibitor clusters—the trifluoromethyl ketones and hydroxyisoxazolines—have also been evaluated. All three clusters inhibit the fungal HDAC, which makes them interesting compound classes with a novel mode-of-action to control phytopathogens that have developed a resistance to commercial fungicides.