Thidiazuron

Thidiazuron

噻苯隆

1-phenyl-3-(1,2,3-thiadiazol-5-yl)urea

N-phenyl-N′-1,2,3-thiadiazol-5-ylurea

51707-55-2

C₉H₈N₄OS

Herbicides > Urea herbicides

mainly used for cotton and peanut

EC = Emulsifiable concentrate
SC = Suspension concentrate (=flowable concentrate)
WP = Wettable powder

Thymo+Thidiazuron
Thidiazuron+Ethephon
Gibberellic acid+Thidiazuron
Gibberellic acid A4,A7+Thidiazuron
Diuron+Thidiazuron+Ethephon
 Premix Parters: bensulfuron-methyl; bensulfuron-methyl mefenacet; propanil; diuron

Molecular weight:220.2; Physical form:Colourless, odourless crystals. Melting point:210.5-212.5 °C ( decomp.); Vapour pressure:4 × 10-6 mPa (25 °C) (Langmuir method); Henry constant:2.84 × 10-8 Pa m3 mol-1 ( calc.); Partition coefficient(n-octanol and water):logP = 1.77 ( pH 7.3); pKa:8.86; Solubility:In water 31 mg/l (pH 7, 25 °C). In hexane 0.002, methanol 4.20, dichloromethane 0.003, toluene 0.400, acetone 6.67, ethyl acetate 1.1 (all in g/l, 20 °C).; Stability:Rapidly converted to photoisomer, 1-phenyl-3-(1,2,5-thiadiazol-3-yl)urea, in presence of light (l >290 nm). Hydrolytically stable at room temperature from pH 5-9. No decomposition in accelerated storage stabili;

Oral:Acute oral LD₅₀ for mice >5000, rats >4000 mg/kg. Percutaneous:Acute percutaneous LD₅₀ for rats >1000, rabbits >4000 mg/kg. Mild eye irritant; non-irritating to skin (rabbits). No skin sensitisation (guinea pigs). Inhalation: LC₅₀ (4 h) for rats >2.3 mg/l air.

Ecotoxicology: 
Bees:Non-toxic to honeybees.Birds:Acute oral LD₅₀ for Japanese quail >3160 mg/kg. Dietary LC₅₀ (8 d) for bobwhite quail and mallard ducks >5000 mg/kg diet.Daphnia:LC₅₀ (48 h) >10 mg/l.Fish: LC₅₀ (96 h) for rainbow trout, bluegill sunfish, and catfish >1000 mg/l.Worms: LC₅₀ (14 d) for earthworms >1400 mg/kg. 

Environmental fate: 
Animals:In rats and goats, metabolism involves hydroxylation of the phenyl group, followed by formation of water-soluble conjugates. Following oral administration, the compound is excreted in the urine and faeces within 96 hours.Soil:Strongly adsorbed by soil. DT₅₀ in soil c. 26-144 d (aerobic), 28 d (anaerobic). Essential soil microbial processes are only temporarily influenced, if at all.Plant:Only small amounts of residue (normally <0.1 mg/kg) are likely in cottonseed.

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