The application discloses a
diflunisal derivative, a preparation method and application thereof, and belongs to the technical field of agricultural fungicides. The preparation method comprises the following steps: mixing 2', 4'-difluoro-4-hydroxy-[1, 1'-
biphenyl]-3-
carboxylic acid, a condensing agent and an
organic base in an ice bath and an
inert organic solvent, and activating for 10-30 minutes; then adding an amine compound with a general formula of R-NH2, and stirring and reacting at
room temperature for 20-28 hours; after the reaction is completed, extraction, washing,
drying, concentration and
column chromatography purification are performed, so that the target
diflunisal derivative is obtained. The compound disclosed by the application has a novel structure, shows excellent inhibitory activity on cucumber
botrytis cinerea, rice pellicularia sasakii,
brassica rapa
sclerotium, wheat
fusarium graminearum and other
plant pathogenic fungi, can be used as an
active ingredient for preparing an agricultural
fungicide or a
fungicide composition, and provides a new
lead structure for developing a new
succinate dehydrogenase inhibitor
fungicide.