Azimsulfuron 四唑嘧磺隆

中文通用名称：四唑嘧磺隆
英文通用名称：azimsulfuron （BSI,ISO）
商品名称：Azin、Gulliver、康宁
试验代号：DPXA-8947、IN-A8947、A8947、JS-458
化学名称：1-[(4,6-二甲氧基嘧啶-2-基)-3-[1-甲基-4-(2-甲基-2H-四唑-5-基)吡唑-5-基磺酰基]脲
1-(4,6-dimethoxypyrimidin-2-yl)-3-[1-methyl-4-(2-methyl-2H-tetrazol-5-yl)pyrazol-5-ylsulfonyl]urea
CA主题索引名及CAS登录号：
N-[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]-1-methyl-4-(2-methyl-2H-tet-razol-5-yl)-1H-pyrazole-5-sulfonamide
[120162-55-2]

化学结构类型：磺酰脲类
理化性质：纯品为白色固体；熔点170℃；密度1.41；蒸气压为4.0×10-9Pa (25℃)；分配系数LogP(25℃)＝0.646(pH 5)，-1.37(pH 7)，-2.08(pH 9)；溶解度(20℃，mg/l)为：水中72.3(pH 5)、1050(pH7)、6536(pH 9)，乙腈13.9，丙酮26.4，甲醇2.1，甲苯1.8，正己烷<0.2，乙酸乙酯13.0， 二氯甲烷65.9；p K a 3.6。

毒性：大鼠急性经口LD50：>5000mg/kg；兔急性经皮LD50：>2000mg/kg；大鼠急性吸入LC50：5.9mg/l。对兔眼睛和兔皮无刺激。野鸭和鹌鹑急性经口LD50：>2250mg/kg；鱼毒LC50(96小时，ppm)：鲤鱼>300，鳟鱼 154，大翻车鱼>1000。无致突变性。

制剂：水分散颗粒剂。
作用机理：四唑嘧磺隆与其它磺酰脲类除草剂一样是乙酰乳酸合成酶(ALS)的抑制剂。通过杂草根和叶吸收，在植株体内传导，杂草即停止生长，而后枯死。
适宜作物：水稻。
安全性：四唑嘧磺隆在水稻植株内迅速代谢为无毒物，对水稻安全。

防除对象：主要用于防除稗草、阔叶杂草和莎草科杂草。
使用方法：
水稻苗后施用，使用剂量为8~25克有效成分/公顷。如果与助剂一起使用，用量将更低。20~25克有效成分/公顷施用，可有效地防除稗草、北水毛花、异型莎草、紫水苋菜、眼子菜、花蔺、欧泽泻等；四唑嘧磺隆对稗草和莎草的活性高于苄嘧磺隆，若两者混用，增效明显，混用后，即使在遭大水淋洗、低温情况下，除草效果仍很稳定。

合成方法：
以丙二腈为起始原料，与原甲酸三甲酯反应后与甲肼缩合制得中间体吡唑胺，再与叠氮化钠反应、经甲基化，重氮化、磺酰化、胺化，最后与嘧啶氨基甲酸苯酯缩合，处理即得目的物。反应式为：

主要原料与中间体：丙二腈、叠氮化钠、二甲氧基嘧啶胺、氯甲酸苯酯
分析方法：HPLC
开发公司：美国杜邦公司。

azimsulfuron
Herbicide
HRAC B WSSA 2; sulfonylurea

NOMENCLATURE
Common name azimsulfuron (BSI, pa E-ISO)
IUPAC name 1-(4,6-dimethoxypyrimidin-2-yl)-3-[1-methyl-4-(2-methyl-2H-tetrazol-5-yl)pyrazol-5-ylsulfonyl]urea
Chemical Abstracts name N-[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]-1-methyl-4-(2-methyl-2H-tetrazol-5-yl)-1H-pyrazole-5-sulfonamide
CAS RN [120162-55-2] Development codes IN-A8947; DPX A8947 (DuPont); A8947; JS-458

PHYSICAL CHEMISTRY
Composition Tech. is >98%. Mol. wt. 424.4 M.f. C13H16N10O5S Form White powdered solid, with a phenolic odour. M.p. 170 ºC V.p. 4.0 ´ 10-6 mPa (25 °C) KOW logP = 4.43 (pH 5), 0.043 (pH 7), 0.008 (pH 9) (all 25 °C) Henry 8 ´ 10-9 (pH 5); 5 ´ 10-10 (pH 7); 9 ´ 10-11 (pH 9) (all in Pa m3 mol-1, calc.) S.g./density 1.12 (25 °C) Solubility In water 72.3 (pH 5), 1050 (pH 7), 6536 (pH 9) (all in mg/l, 20 ºC). In acetone 26.4, acetonitrile 13.9, ethyl acetate 13.0, methanol 2.1, dichloromethane 65.9, toluene 1.8, hexane <0.2 (all in g/l, 25 °C). Stability Hydrolysis DT50 89 (pH 5), 124 (pH 7), 132 (pH 9) d (25 °C). Degradation was through cleavage of the sulfonylurea bridge to give mainly the tetrazolylpyrazole sulfonamide and aminodimethoxypyrimidine. DT50 in irradiated aqueous solution, corrected for hydrolysis, was 103 (pH 5), 164 (pH 7), 225 (pH 9) d (25 °C). Indirect photodegradation has also been studied (A. C. Barefoot, Proc. Br. Crop Prot. Conf. - Weeds,1995, 2, 713). pKa 3.6

COMMERCIALISATION
History Reported by T. Marquez et al. (Proc. Br. Crop Prot. Conf. - Weeds, 1995, 1, 65). Patents US 4746353 Manufacturers DuPont

APPLICATIONS
Biochemistry Branched chain amino acid synthesis (ALS or AHAS) inhibitor. Acts by inhibiting biosynthesis of the essential amino acids valine and isoleucine, hence stopping cell division and plant growth. Selectivity derives from rapid metabolism in the crop. Metabolic basis of selectivity in sulfonylureas reviewed (M. K. Koeppe & H. M. Brown, Agro-Food-Industry, 6, 9-14 (1995)). Mode of action Post-emergence herbicide with mainly foliar uptake; translocated in xylem and phloem. Initial symptoms are cessation of growth and chlorosis, followed by reddish colouration, then necrosis. Uses Post-emergence, selective control of Echinochloa spp. and other annual and perennial broad-leaved and sedge weeds in Southern European rice, at 20-25 g/ha. Formulation types WG. Selected products: 'Gulliver' (DuPont)

OTHER PRODUCTS
'Azin' (DuPont) mixtures: 'Bazooka 36' (+ bensulfuron-methyl+ cyhalofop-butyl+ thenylchlor) (Nihon Nohyaku); 'Bazooka A' (+ bensulfuron-methyl+ cyhalofop-butyl) (Nihon Nohyaku, Hokko, Tokuyama, DuPont); 'Dancing A' (+ bensulfuron-methyl+ indanofan) (Nihon Nohyaku); 'Dancing-Power A' (+ bensulfuron-methyl+ clomeprop+ indanofan) (Nihon Nohyaku); 'Inebrite' (+ bensulfuron-methyl+ fentrazamide) (Bayer CropScience); 'Kusastop A' (+ bensulfuron-methyl+ indanofan) (Nihon Nohyaku); 'Masakari A Jumbo' (+ bensulfuron-methyl+ clomeprop+ indanofan) (Nihon Nohyaku); 'Papika A I Kilo' (+ bensulfuron-methyl+ cyhalofop-butyl+ thenylchlor) (Nihon Nohyaku, Hokko, Tokuyama, Dow AgroSciences, DuPont); 'Papika A' (+ bensulfuron-methyl+ cyhalofop-butyl+ thenylchlor) (Tokuyama, Nihon Nohyaku, Hokko, DuPont, Dow AgroSciences); 'Weedless A36' (+ bensulfuron-methyl+ cafenstrole+ daimuron) (Sankyo Agro, DuPont, Eiko Kasei, SDS Biotech KK); 'Wydori A' (+ bensulfuron-methyl+ dimethametryn+ pretilachlor) (Nihon Nohyaku) Discontinued products mixtures: 'Tabijin A' * (+ bensulfuron-methyl+ cyhalofop-butyl+ pretilachlor+ pyriminobac-methyl) (Kumiai)

ANALYSIS
Product and residue analysis by hplc/ms/ms (Handbook of Residue Analytical Methods, pp 400-410).

MAMMALIAN TOXICOLOGY
Oral Acute oral LD50 for rats >5000 mg/kg. Skin and eye Acute percutaneous LD50 for rats >2000 mg/kg. Not irritating to eyes or skin (rabbits). Not a skin sensitiser (guinea pigs). Inhalation LC50 (4 h) for rats >5.84 mg/l. NOEL (2 y) for male rats 34.3 mg/kg b.w. daily; (1 y) for male dogs 17.9 mg/kg b.w. daily. ADI 0.10 mg/kg b.w. Other Not mutagenic (Ames), not genotoxic, not carcinogenic. Toxicity class WHO (a.i.) U EC classification N; R50, R53

ECOTOXICOLOGY
Birds Acute oral LD50 for bobwhite quail and mallard ducks >2250 mg/kg. Dietary LC50 (8 d) for bobwhite quail and mallard ducks >5260 mg/kg. Fish LC50 (96 h) for carp >300, bluegill sunfish >1000, rainbow trout 154 ppm. Daphnia LC50 (48 h) >1000 ppm; NOEC (21 d) >5.4 mg/l. Algae EC50 for Selenastrum capricornutum 12 mg/l. Other aquatic spp. EC50 for Lemna Gibba 0.8 mg/l. Bees LD50 (48 h) (oral) >25 mg/bee; (contact) >1000 mg/bee. Worms LC50 >1000 mg/kg.

ENVIRONMENTAL FATE
Animals Following oral administration to rats, >95% azimsulfuron was excreted within 2 d, 60-73% in unmetabolised form. The major metabolic pathway was O-demethylation followed by pyrimidine ring hydroxylation and subsequent O-conjugation; a pyrimidine ring-cleaved guanidine was also identified; N-demethylation of pyrazole and tetrazole rings and cleavage of the sulfonylurea bridge were also observed as minor routes. Plants Metabolism was rapid; little parent compound was found in any plant tissue at maturity. Soil/Environment Soil degradation in both flooded soils and under aerobic conditions has been studied. The most significant mechanisms are indirect photolysis and soil metabolism, together with chemical hydrolysis. Degradation products have been identified. No detectable residues in the field at harvest at depths of 0 to 50 cm. See A. C. Barefoot (Proc. Br. Crop Prot. Conf. - Weeds,1995, 2, 713).