Fomesafen 氟磺胺草醚

氟磺胺草醚

英文通用名fomesafen
化学名称： 5-(2-氯a,a、a-三氟-对甲苯氧基)-N-甲磺酰基-1-硝苯甲酰胺
理化性质：药有效成份含量为95%，外观灰白色粉末状固体。熔点218—221℃，密 氟磺胺草醚分子式
度：1．28g/cm3，蒸气压<0.1mpa(50℃)。溶解性在水中的溶解度取决于PH值的大小，50mg/L(pH7)，pHl—2则小于1mg/L；丙酮300g/L；二氯甲烷10g/L：二甲苯1.9g/L；甲醇20g/L；酸性pH值约为2.7(20℃)。能生成水溶性盐。
其他名称虎威(Flex)、除豆莠、氟磺草醚、PP021、闲锄伴侣
毒性对人畜低毒。大鼠急性经口LD50：雄性大鼠3160 毫克/公斤， 雌性大鼠2870毫克/公斤；雄性小鼠4300毫克/公斤，雌性小,4220毫克/公斤。对皮肤和眼睛有轻度刺激作用。对鱼类和水生生物毒性很低，对鸟和蜜蜂亦低毒。
剂型25%水剂。
特点是一种具有高度选择性的大豆、花生田苗后除草剂，能有效地防除大豆、花生田阔叶杂草和香附子，对禾本科杂草也有一定防效。能被杂草根叶吸收，使其迅速枯黄死亡，喷药后4-6小时遇雨不影响药效，对大豆安全。

适用范围

适用于大豆、花生田防除苘麻、铁苋菜、三叶鬼针草、苋属 氟磺胺草醚
、豚草属、油菜、荠菜、藜、鸭跖草属、曼陀罗、龙葵、裂叶牵牛、粟米草、匾蓄、宾州蓼、马齿苋、刺黄花稔、野苋、决明、地锦草、猪殃殃、水棘针、酸浆属、田菁、苦苣菜、蒺藜、车轴草、荨麻、宾州苍耳、刺苍耳、苍耳等阔叶杂草。也可用于果园，橡胶种植园防除阔叶杂草。
使用方法 大豆苗后1-3片复叶时，杂草1-3叶期，每亩用25%水剂68-132毫升，对水20-30公斤，均匀喷雾杂草茎叶。药液中加适量非离子型表面活性剂效果更好。

注意事项

1.氟磺胺草醚在土壤中持效期长，如用药量偏高，对第二年种植敏感作物，如白菜、谷子、高粱、甜菜、玉米、小米、亚麻等均有不同程度药害在推荐剂量下，不翻耕种玉米、高粱，都有轻度影响。应严格掌握药量，选择安全后茬作物。
2.在果园中使用，切勿将药液喷到树叶上。
3.氟磺胺草醚对大豆安全，但对玉米、高粱、蔬菜等作物敏感，施药时注意不要污染这些作物，以免产生药害。
4.用量较大或高温施药,大豆或花生可能会产生灼伤性药斑,一般情况下几天后可正常恢复生长,不影响产量.

fomesafen
Herbicide
HRAC E WSSA 14; diphenyl ether

NOMENCLATURE
fomesafen
Common name fomesafen (BSI, draft E-ISO, ANSI); fomésafène ((m) draft F-ISO)
IUPAC name 5-(2-chloro-a,a,a-trifluoro-p-tolyloxy)-N-methylsulfonyl-2-nitrobenzamide
Chemical Abstracts name 5-[2-chloro-4-(trifluoromethyl)phenoxy]-N-(methylsulfonyl)-2-nitrobenzamide
CAS RN [72178-02-0] EEC no. 276-439-9 Development codes PP021 (ICI)

fomesafen-sodium
CAS RN [108731-70-0]

PHYSICAL CHEMISTRY
fomesafen
Mol. wt. 438.8 M.f. C15H10ClF3N2O6S Form White crystals. M.p. 219 °C V.p. <4 ´ 10-3 mPa (20 °C) KOW logP = 2.9 (pH 1), <2.2 (pH 4-10) Henry <2 ´ 10-7 Pa m3 mol-1 (pH 7, 20 °C) S.g./density 1.61 (20 °C) Solubility In pure water c. 50, <10 (pH 1-2), 10 000 (pH 9) (all in mg/l, 20 ºC). Stability Stable in storage for at least 6 months at 50 ºC. Decomposed by light. Stable at pH 3 and 11 (40 °C). Stable to aqueous photolysis for 32 d (pH 7, 25 °C). pKa 2.83 (20 ºC); forms water-soluble salts (e.g. fomesafen-sodium)

fomesafen-sodium
Mol. wt. 460.7 M.f. C15H9ClF3N2NaO6S

COMMERCIALISATION
History Herbicide reported by S. R. Colby et al. (Proc. Int. Congr. Plant Prot., 10th, 1983, 1, 295). Introduced by ICI Plant Protection Division (now Syngenta AG). Patents EP 3416 Manufacturers Sannong; Syngenta

APPLICATIONS
Biochemistry Protoporphyrinogen oxidase inhibitor. Mode of action Selective herbicide, absorbed by both leaves and roots, with very limited translocation in the phloem. Uses Early post-emergence control of broad-leaved weeds in soya beans. Applied at 200-400 g/ha. Phytotoxicity Non-phytotoxic to soya beans and to other crops such as beans of the genus Phaseolus and the leguminous cover crops Pueraria and Calapogonium. Formulation types ME; SL.

fomesafen-sodium
Selected products: 'Flex' (Syngenta); 'Flexstar' (Syngenta); 'Reflex' (Syngenta)

OTHER PRODUCTS
fomesafen-sodium
Mixtures: 'Fusiflex' (+ fluazifop-P-butyl) (Syngenta); 'Reflex T' (+ terbutryn) (Syngenta); 'Tornado' (+ fluazifop-P-butyl) (Syngenta); 'Twister' (+ fenoxaprop-P-ethyl+ fluazifop-P-butyl) (Syngenta); 'Typhoon' (+ fluazifop-P-butyl) (Syngenta) Discontinued products mixtures: 'Faster' * (+ bentazone-sodium) (BASF)

ANALYSIS
Product analysis by hplc with u.v. detection. Residue analysis in soil by hplc; in crops by tlc, hplc or nmr. Details available from Syngenta.

MAMMALIAN TOXICOLOGY
fomesafen
Oral Acute oral LD50 for male rats 1250-2000, female rats 1600 mg/kg. Skin and eye Acute percutaneous LD50 for rabbits >1000 mg/kg. Mild skin irritant; mild to moderate eye irritant (rabbits). Extreme skin sensitiser (Magnusson & Kligman test), not a skin sensitiser (ear/flank Stevens test, guinea pigs). Inhalation LC50 (4 h) for male rats 4.97 mg/l. NOEL (2 y) for rats 5 mg/kg b.w. daily; (18 mo) for mice 1 mg/kg b.w. daily (liver tumours in mice due to peroxisome proliferation - not relevant to man); (6 mo) for dogs 1 mg/kg b.w. daily. NOEL developmental toxicity for rabbits 2.5 mg/kg b.w. daily. ADI 0.05 mg/kg. Other Genotoxicity negative. Not oncogenic. Toxicity class WHO (a.i.) III; EPA (formulation) III EC classification Xn; R22

fomesafen-sodium
Oral Acute oral LD50 for male rats 1860, female rats 1500 mg/kg. Skin and eye Acute percutaneous LD50 for rabbits >780 mg/kg. Other Not oncogenic.

ECOTOXICOLOGY
fomesafen
Birds Acute oral LD50 for mallard ducks >5000 mg/kg. Dietary LC50 (5 d) for mallard ducks and bobwhite quail >20 000 mg/kg. Fish LC50 (96 h) for rainbow trout 170, bluegill sunfish 1507 mg/l. Daphnia EC50 (48 h) 0.33 g/l. Algae EC50 170 mg/l. Bees Low oral and contact toxicity to bees. LD50 (oral) ³50 mg/bee; (contact) ³100 mg/bee. Worms LC50 (14 d) >1000 mg/kg.

ENVIRONMENTAL FATE
Plants In soya beans, the diphenyl ether bond is rapidly cleaved to give inactive metabolites. Soil/Environment In soil, degrades slowly under aerobic conditions, DT50 >6 mo, but degrades more rapidly under anaerobic conditions, DT50 <1-2 mo. Koc 34-