Pyrifenox

Pyrifenox

啶斑肟

2′,4′-dichloro-2-(3-pyridyl)acetophenone (EZ)-O-methyloxime

1-(2,4-dichlorophenyl)-2-(3-pyridinyl)ethanone O-methyloxime

88283-41-4

C₁₄H₁₂Cl₂N₂O

Fungicides > Pyridine fungicides

Fungicide

Emulsifiable concentrate, wettable powder. 
Premix Parters: propiconazole;

Molecular weight:295.2; Physical form:Pale yellow, viscous liquid, with a slightly sweet odour. Density:1.28 (20 °C); Composition:A mixture of (E)- and (Z)- isomers. Flash point:106 °C (1013 mbar); Vapour pressure:1.7 mPa (25 °C); Henry constant:5.8 × 10-3 Pa m3 mol-1 ( calc.); Partition coefficient(n-octanol and water):logP = 3.4 ( pH 5.0), 3.7 ( pH 7.0), 3.7 ( pH 9.0) (all 25 °C); pKa:4.61, weak base; Solubility:In water 300 ( pH 5.0), 150 ( pH 6.7), 130 ( pH 9.0) (all in mg/l, 25 °C). In n-hexane 210 g/l (25 °C). Completely miscible with ethanol, acetone, toluene and n-octanol.; Stability:Stable for >3 years in a closed container at room temperature. Stable to u.v. light and to hydrolysis in water ( pH 3, 7, 9; 50 °C).Tech: Tan-colored, slightly viscous liquid. Boiling point >150°C at 0.1 mm Hg, density 1.28 g/ml at 20°C, vapor pressure 1.9 mPa at 25°C. Solubility: n-hexane 210 g/l; completely miscible with acetone, ethanol, n-octanol, toluene.

Oral:Acute oral LD₅₀ for rats 2912, mice >2000 mg/ kg. Percutaneous:Acute percutaneous LD₅₀ for rats >5000 mg/kg. Weak irritant to skin (humans); non-irritant to eyes (rabbits). Not a skin sensitiser (guinea pigs). Inhalation: LC₅₀ (4 h) for rats >2048 mg/m³ air. ADI:0.18 mg/ kg (Novartis proposed); 0.35 mg/ kg (WHO, 1992).

Ecotoxicology:
 Algae: EC₅₀ (96 h) for Scenedesmus subspicatus 0.095 mg/l.Bees: LD₅₀ (48 h) (oral) 59µg/bee; (contact) 70µg/bee.Birds:Acute oral LD₅₀ (14 d) for mallard ducks and bobwhite quail >2000 mg/ kg.Daphnia: EC₅₀ (48 h) 3.6 mg/l.Fish: LC₅₀ (96 h) for rainbow trout 7.1, mirror carp 12.2, bluegill sunfish 6.6 mg/l.Worms: LC₅₀ (14 d) for earthworms 733 mg/ kg.Other beneficial spp.:200 g/l EC formulation harmless to Typhlodromus pyri and Orius insidiosus; slightly toxic to Coccinella septempunctata and Trichogramma cacoeciae (IOBC). 

Environmental fate: 
Animals:In rats, following oral administration, pyrifenox is rapidly absorbed, metabolised and excreted in the urine and faeces. There are no indications of bioretention in tissue or organs.Soil:Moderate soil mobility, no tendency toward bioaccumulation, little potential for environmental persistence, and fairly rapid dissipation in plants, soil, water and animals. See R. P. Hanni & A. J. Schuler in Comp. Anal. Profiles, Chapt. 3. Plant:Relatively rapid degradation in plants. DT₅₀ in peanut leaves 4 d, apple leaves 3 d, apple fruit 9 d. The main degradation pathway is by hydrolysis and elimination of the oxime group. WATER SOLUBILITY: At 25°C: 150 mg/l (pH 6.7), 130 mg/l (pH 9)

Signal Word:CAUTION; Hazard Class:III(Slightly hazardous)