Terbuthylazine

Terbuthylazine

特丁津

N²-tert-butyl-6-chloro-N⁴-ethyl-1,3,5-triazine-2,4-diamine

6-chloro-N-(1,1-dimethylethyl)-N′-ethyl-1,3,5-triazine-2,4-diamine

5915-41-3

C₉H₁₆ClN₅

Herbicides > Triazine herbicides

Herbicide

Terbuthylazine+Mesotrione+Propisochlor
S-metolachlor+Terbuthylazine
Nicosulfuron+Terbuthylazine

Molecular weight:229.7; Physical form:Colourless powder. Density:1.188 (20 °C); Composition:Tech. is ×96 % pure. Melting point:177-179 °C; Flash point:>150 °C; Vapour pressure:0.15 mPa (25 °C); Henry constant:4.05 ×10-3 Pa m3 mol-1 ( calc.); Partition coefficient(n-octanol and water):logP = 3.21 (unionised); pKa:2.0, v. weak base; Solubility:In water 8.5 mg/l ( pH 7, 20 °C). In acetone 41, ethanol 14, n-octanol 12, n-hexane 0.36 (all in g/l, 25 °C).; Stability:Stable in neutral, weakly acidic and weakly alkaline media,in isopropanol about 1%; in dimethylformamide about 10%.; hydrolysed in acidic or alkaline media; DT50 (20 °C) ( calc.) 8 d ( pH 1), 12 d ( pH 13).

Oral:Acute oral LD₅₀ for rats 1590->2000 mg/kg. Percutaneous:Acute percutaneous LD₅₀ for rats >2000 mg/kg. No skin or eye irritation. Not a skin sensitiser. Inhalation: LC₅₀ (4 h) for rats >5.3 mg/l air. Phytotoxicity:Phytotoxic to many annual plants and to aquatic plants. ADI:0.075 mg/kg b.w.

Ecotoxicology: 
Algae: EC₅₀ (72 h) for Scenedesmus subspicatus 0.016-0.024 mg/l.Bees:LD₅₀ (oral and contact) >100 µg/bee.Birds:Acute oral LD₅₀ for ducks and quail >1000 mg/kg. Dietary LC₅₀ (8 d) for ducks and quail >5620 ppm.Daphnia: LC₅₀ (48 h) 21-50.9 mg/l.Fish: LC₅₀ (96 h) for rainbow trout 3.8-4.6, bluegill sunfish 7.5, carp and catfish 7.0 mg/l.Worms: LC₅₀ (7 d) for earthworms >200 mg/kg soil.Other beneficial spp.:No effects on bacterial respiration and nitrification in range 10.9-109 mg/kg soil. 

Environmental fate: 
Animals:In mammals, following oral administration, 72-84% is eliminated in the urine and faeces within 24 h, and almost all within 48 h. A de-ethyl metabolite forms rapidly, followed by conjugates of products formed by oxidation of one methyl group of the terSoil:Adsorption on soils is strong: K_oc 162-278, K_d 2.2-25 are typical values for light agricultural soils. Terbuthylazine is only slightly mobile. Microbial degradation proceeds mainly by de-ethylation aPlant:Triazine-tolerant plants (e.g. maize) rapidly de-chlorinate terbuthylazine to hydroxy-terbuthylazine. Various amounts of de-ethylated and hydroxy de-ethylated metabolites are produced, depending on the plant species.

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