Design, synthesis and antifungal activity of new substituted difluoromethylpyrimidinamine derivatives

Synopsis: Starting from ethyl 4,4-difluoro-3-oxobutanoate that is the common raw material in some newly launched important succinate dehydrogenase inhibitor (SDHI) fungicides, a novel difluoromethylpyrimidine lead structure was found by means of the intermediate derivatization methods (IDM), followed by a series of interesting modifications to afford the optimized compound with a promising fungicidal activity (EC50=2.16mg/L) against southern corn rust.