FENBUCONAZOLE

The Uses of FENBUCONAZOLE

Fenbuconazole is a conazole based fungicide used as a spray for the control of leaf spot, yellow and brown rust, powdery mildew and net blotch on wheat and barley and apple scab, pear scab and apple p owdery mildew on apples and pears.

The Uses of FENBUCONAZOLE

Agricultural fungicide.

The Uses of FENBUCONAZOLE

Fenbuconazole is used for control of Septoria, Puccinia rusts, bunt, smut and Rhyncosporium secalis on cereals; powdery mildew and scab on pome fruit; brown rot and powdery mildew on stone fruit; powdery mildew, black rot and grey mould on vines, rust on beans and bean leaf spot on sugar beet. It is also used for control of a wide range of diseases on field crops, rice, bananas, tree nuts, vegetables and ornamentals. It can also be used in foliar, post-harvest and seed treatments.

Definition

ChEBI: 4-(4-chlorophenyl)-2-phenyl-2-(1,2,4-triazol-1-ylmethyl)butanenitrile is a member of the class of triazoles that is 1-chloro-4-(3-phenylpropyl)benzene substituted at position 3 of the propyl moiety by cyano and 1,2,4-triazol-1-ylmethyl groups. It is a member of triazoles, a nitrile and a member of monochlorobenzenes.

Metabolic pathway

A number of sites in the fenbuconazole molecule are susceptible to enzymic attack. Consequently, a large variety of metabolites may be formed by oxidative attack on the phenolic rings or the aliphatic benzylic carbon atom adjacent to the 4-chlorophenyl ring. In mammals, oxidation at the benzylic carbon atom is an important pathway, which gives rise to the corresponding alcohol or ketone. This pathway also leads to lactone formation via hydrolysis of the nitrile group and elimination of a molecule of water. The alcohol may also form conjugates with glucuronic or sulfuric acid. Additional reactions in mammals involve hydroxylation of the phenolic rings.
In plants, oxidation at the benzylic carbon is an important step to further metabolites and cleavage of the linkage to the triazole ring generates triazole, which is subsequently incorporated in a number of metabolic products. Information presented in this entry is based on the PSD Evaluation (PSD, 1995).

Degradation

Fenbuconazole is thermally stable up to 150 °C and there was no observed degradation when fenbuconazole was incubated in the dark in aqueous solutions at pH 5,7 and 9 for up to 30 days at 25 °C.
When an aqueous solution of fenbuconazole (concentration 1.5μg ml^-1, pH 7) was irradiated with a xenon arc lamp (filtered to remove wavelengths below 290 nm), the overall radioactivity was 105% of the original amount and the only compound detected was fenbuconazole.