7983. Pyrifenox

Nomenclature

CAS number: 88283-41-4
1-(2,4-Dichlorophenyl)-2-(3-pyridinyl)ethanone O-methyloxime; 2′,4′-dichloro-2-(3-pyridyl)acetophenone O-methyloxime; ACR-3453A; Ro-15-1297; Dorado (Syngenta).
C14H12Cl2N2O; mol wt 295.16.
C 56.97%, H 4.10%, Cl 24.02%, N 9.49%, O 5.42%.

Description and references

Ergosterol biosynthesis inhibitor for use on crops. Prepn: F. Dorn, DE 3310148; idem, US 4605656 (1983, 1986 both to Hoffmann-La Roche). Review of physical properties, toxicity and bioactivity: P. Zobrist et al., Proc. Br. Crop Prot. Conf. - Pests Dis. 1986, 47-53; of field trials: G. Neumann et al., Meded. Fac. Landbouwwet. Rijksuniv. Gent 54, 635-642 (1989).

Chemical structure

Properties

Slightly viscous, tan liquid with mild aromatic odor. bp0.1 >150°. vapor pressure at 25°: 1.4 × 10-5 torr. Soly (at 20°) in water at pH 7: 115 mg/l; in hexane: <1 g/l; in acetone, ethyl acetate, chloroform, diethyl ether, DMF, isopropyl alcohol, toluene: >250 g/l. LD50 in rats (mg/kg): 950 i.p.; 2900 orally; >5000 dermally; LC50 by inhalation in rats: >2.05 mg/l (Zobrist).

Use

Agricultural fungicide.