Graminicidal activity

Three main areas of the 4-aryl-pyrazolidine-3,5-dione scaffold were modified during the optimization phase towards graminicidal activity and selectivity in small grain cereals. A major breakthrough with regard to the herbicidal activity was achieved as aryl moieties bearing ethyl, ethynyl or methoxy groups in the... 

A 2-ethyl group leads to an increased activity and a 2,6-diethyl-4-methyl substitution pattern boosts the graminicidal activity. The level of activity can even be improved with a 2-ethynyl or a 2-methoxy-substituent in a 2,4,6-pattern. However, these two functionalities induce a higher level of phytotoxicity in cereals. Interestingly, 2,6-dimethoxy or 2,6-dibromoaryl ADs were found to be almost inactive. 

Pinoxaden, Axial , Adigor , Cloquintocet-mexyl, Discovery, Structure-Activity Relationship, Herbicide, Grass Weed Control, Graminicide, Postemergence, Cereals, Wheat, Barley... 

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