120928-09-8

Acaricide and insecticide.

Fenazaquin is a non-systemic acaricide/insecticide used widely in controlling mites and other related pests in fruits, vegetables and tea.

Fenazaquin is an acaricide mainly used for control of mites (Eutetranychus, Panonychus and Tetranychus spp.) on pome and citrus fruits and glasshouse-grown ornamental plants.

ChEBI: Fenazaquin is a member of quinazolines. It has a role as an acaricide and a mitochondrial NADH:ubiquinone reductase inhibitor.

Fenazaquin is a lipophilic compound and hence is immobile in soils and is not translocated in plants. The main pathways of metabolism involve cleavage of the bridging group between the quinazoline and phenyl rings, oxidation of the tert-butyl sustituent and of the heterocyclic portion of the quinazoline ring and cleavage of that ring. Most of the information is taken from a pamphlet produced by the manufacturer of the compound in which full experimental details were not given (DowElanco, 1993).

Fenazaquin is hydrolysed under acidic conditions but the rate is slow under neutral and alkaline conditions. Half-lives were 8,442 and 584 days (22 °C) at pH values of 5, 7 and 9, respectively. Hydrolysis occurs by cleavage of the ether linkage to form quinazolin-2-ol (2) and an alcohol (3) as shown in Scheme 1. The major route of degradation in aquatic environments is by photolysis, the main products (2 and 3) being formed by cleavage of the ether lmkage and include the alkene (4) (DowElanco, 1993).