amidosulfuron

amidosulfuron

CA Registry Number: 120929-37-7 

English name: amidosulfuron 

Chemical Name: 1 - (4,6 - dimethoxy pyrimidine -2-- yl) -3-- methylsulfonylpyridine (methyl) amino sulfonyl urea. 1 - (4,6-dimethoxypyrimidin-2-yl)-3-mesyl (methyl) sulfarnoylurea. 

Other names: broad thinking was, Hoestar, Adret, Gratil, Allstate 

Molecular formula:: C9H15N5O7S2 

MW: 369.37 

Structure: 

Properties: pure product is white granular solid. Melting point 160 ~ 163 ℃, relative density of 1.5 (20 ℃). Vapor pressure of 2.2 × 10-5Pa (20 ℃). Partition coefficient KowlogP (20 ℃) = 1.63 (pH2). Solubility (20 ℃, mg / L) as follows: water 3.3 (pH3), 9 (pH5.8), 13500 (pH10), isopropanol 99, methanol 872, acetone 8100. Half-life in water (20 ℃):> 33.9d (pH5),> 365d (pH7), at room temperature for 24 months stability. pKa3.58. 

Toxicity: large (small) mouse acute oral LD50> 5000mg/kg. Acute percutaneous LD50> 5000mg/kg. Acute inhalation LC50 (4h)> 1.8mg / L of rabbit skin irritation rabbit a slight eye irritant in guinea pig skin sensitization. NOEL (no effect dose of short feeding. Hereinafter) data: male rats (2a) 19.45mg/kg.d. ADI (short for daily maximum intake, the same below) value: 0.2mg/kg. No carcinogenic, teratogenic, mutagenic. Mountain Gear ducks and quail acute oral LD50> 2000mg/kg. Rainbow trout LC50 (96h)> 320mg / L. Bees, acute oral LD50> 1000ug / only. Earthworm LC50 (14d)> 1000mg/kg soil. 

Formulation: 50% of the acid-ethyl (Allstate) water dispersible granules. Mixture: Si-based materials have wide iodized salt metsulfuron. 

Characteristics and role spectrum herbicide: acetolactate synthase (ALS) inhibitors. Absorbed through the roots and leaves of weeds, in plant transfer, that is to stop the growth of weeds, leaf chlorosis, and then die. After application of the herbicidal effects from the weather, the effect is stable. Low toxicity and residue, environmentally safe. 

For cereal crops such as wheat, winter wheat, durum wheat, barley, rye, oats, as well as lawns and pastures. Can effectively control broadleaf weeds in wheat fields, such as a variety of malignant Galium aparine, sophia, chestnut Levin, amaranth, Sonchus, field bindweed, cress, wild radish, the s Polygonum, crispus and so on. Have effects on Galium aparine. Because of its rapid metabolism in the crop as harmless objects, so the cereal crop safety, crop such as corn, after security. Pharmacy does not affect the general result of the rotation, after application if the crop had been accidentally destroyed (eg, frost), available at 15d after switching to any of the spring cereal crops such as barley, oats or other alternative crops such as potatoes, corn, rice, etc. . 

Pesticide use for wheat during the 2 to 4 leaf to flag leaf stage, weeds, between 2 to 8 leaf stage. 2 to 4 in wheat flag leaf to leaf, weed Qimiao after 2 to 5 leaves and vigorous growth, the best spraying period. Its high activity, low application rate, dosage per acre just 1.5 ~ 2g (ai), based on Galium aparine broadleaf weeds in wheat fields a good control effect. Can be mixed, and can be with fenoxaprop (plus antidote), and other herbicides, a one-time lift the weed. Ethyl benzene can also prevent broadleaf herbicides such as to expand the spectrum herbicide. 

The specific methods used: before crop emergence, weeds and 2 to 5 leaf stage when sprayed vigorous growth, a dose of 30 ~ 60g (ai) / hm2 [mu dosage 2 ~ 4g (ai)]. In China, foliage spray, the amount of winter wheat acres 1.5 ~ 2g (ai), the amount of spring wheat acres 1.8 ~ 2g (ai) (or wheat per acre with 50% acid ethyl WG 3 ~ 4g. Spring per acre with 50% acid ethyl WG 3.5 ~ 4g). If the weather is dry, cold or Control in 6 to 8 leaves of older weeds. Usually limit the dosage. If Control in sensitive weeds Galium aparine, even if postponed to weed spraying of 6 to 8 leaves, weeding can achieve better results.

Production methods: acid ethyl sulfonyl chloride key intermediate is isocyanate, methyl chloride, 4,6 - dimethoxy pyrimidine -2-- amine. 

2 - amino -4,6 - dimethyl-pyrimidine Preparation: first by dicyandiamide and ammonium nitrate (or carbonate) obtained the role of guanidine nitrate (or guanidine carbonate), and guanidine nitrate, acetyl acetone, water and potassium carbonate at room temperature. After filtration, drying and other post-processing, 2 - amino -4,6 - dimethyl-pyrimidine, yield 60%. 

Chlorine isocyanate preparation: The sulfur trioxide and cyanogen chloride in chlorinated hydrocarbon solvents in the reaction of chlorosulfonyl isocyanate. In the container with methylene chloride, sulfur trioxide and cyanogen chloride consecutive Walter, temperature is kept 25 ~ 35 ℃, time of 4h, at 25 ~ 30 ℃ under stirring 1h, 98% purity of the product, conversion rate ( by cyanogen chloride meter) is 89%. 

Preparation of acyl-ethyl: chlorine isocyanate in xylene solution and 2 - amino -4,6 - dimethoxy pyrimidine, methyl chloride was stirred at room temperature to 8 ~ 10h, steamed out of xylene, the product used After drying by solvent recrystallization acid ethyl.