Specification :
Fenchlorazole
Common name: fenchlorazole
IUPAC name: ethyl 1-( 2, 4-dichlorophenyl) -5-trichloromethyl-1H-1, 2, 4-triazole-3-carboxylate
Che mical Abstracts name: ethyl 1-( 2, 4-dichlorophenyl) -5-( trichloromethyl) -1H-1, 2, 4-triazole-3-carboxylate
C AS RN: [ 103112-35-2] ; [ 103112-36-3] ( acid)
PHYSICAL CHEMISTRY
Mol. wt.: 403.5; ( acid 375.4) . M.f.: C12H8Cl5N3O2; ( acid C10H4Cl5N3O2) . Form: White, practically odourless solid. M.p.: 108-112 º C. V.p.: 8.9x10-4 mPa ( 20 º C) ( OECD 104) . S.g./ density: 1.7 ( 20 º C) . Solubility: In water 0.9 mg/ l ( pH 4.5, 20 º C) . In n-hexane 2.5, methanol 27, toluene 270, acetone 360, dichloromethane > 500 ( all in g/ l, 20 º C) . Stability: Aqueous hydrolysis DT50 115 d ( pH 5) , 5.5 d ( pH 7) , 0.079 d ( pH 9) .
APPLICATIONS
Biochemistry: Fenchlorazole-ethyl synergises the activity of fenoxaprop-ethyl in susceptible species by enhancing de-esterification to the acid, which is the active form. It also enhances the tolerance of wheat by accelerating the metabolic breakdown of fenoxaprop, leading to the formation of non-phytotoxic degradation products.
Mode of action: Applied to the foliage of wheat in combination with the grass herbicide fenoxaprop-ethyl or fenoxaprop-P-ethyl, it prevents growth retardation, leaf discolouration, and chlorosis of the crop.
Uses: Used as a safener for fenoxaprop-ethyl or fenoxaprop-P-ethyl in post-emergence control of grass weeds in wheat, durum wheat, rye, and triticale.
MAMMALIAN TOXICOLOGY
Oral: Acute oral LD50 for rats > 5000, mice > 2000 mg/ kg.
Skin and eye: Acute percutaneous LD50 for rats and rabbits > 2000 mg/ kg. Non-irritating to eyes and skin ( rabbits) . Non-sensitising to skin ( guinea pigs) .
Inhalation: LC50 ( 4 h) > 1.52 mg/ l.
NOEL: ( 90 d) for rats 1280, male mice 80, female mice 320, dogs 80 mg/ kg diet; ( 1 y) for dogs 80 mg/ kg diet.
Toxicity class: WHO ( a.i.) III ( Table 5)
ECOTOXICOLOGY
Birds: Acute oral LD50 for mallard ducks > 2400 mg/ kg.
Fish: LC50 ( 96 h) for rainbow trout 0.08 mg/ l.
Daphnia: LC50 ( 48 h) 1.8 mg/ l.
Bees: Not harmful to bees: LC50 ( 48 h) > 300 ug/ bee.