TOPRAMEZONE

Topramezone is a highly flexible post-emergent herbicide that's safe for use on all field and specialty maize regardless of trait.

Topramezone is a herbicide that belongs to the class of pyrazolones or benzoylpyrazoles. It can be used to control broad leaved weeds and grass weeds in maize crop protection.

ChEBI: An aromatic ketone that is phenyl 1H-pyrazol-4-yl ketone in which the pyrazolyl group is substituted at positions 1 and 5 by methyl and hydroxy groups, respectively, and in which the phenyl group is substituted at positions 2, 3, and 4 b methyl, 4,5-dihydro-1,2-oxazol-3-yl, and methylsulfonyl groups, respectively. A potent inhibitor of 4-hydroxyphenylpyruvate dioxygenase (HPPD) that is rapily metabolised by corn to non-active substances, it is used as a herbicide for the treatment of broa leaf weeds.

The industrial synthesis of topramezone begins with the construction of a pyrazolone ring, typically formed by condensing hydrazine derivatives with beta-keto esters. This intermediate is then coupled with a benzoyl chloride derivative containing a methylsulfonyl group and a dihydroisoxazole moiety, which are essential for herbicidal activity. The reaction sequence involves acylation, sulfonation, and heterocyclic ring formation under controlled conditions, often using polar aprotic solvents and acid or base catalysts

Systemic, highly selective, rapidly absorbed and translocated. Bleaching: inhibition of 4-hydroxyphenyl-pyruvate-dioxygenase.

Herbicide