Pyrimethanil 嘧霉胺

嘧霉胺

中文通用名：嘧霉胺
[1]英文通用名：Pyrimethanil(ISO,BSI)
化学名称：N-（4,6-二甲基嘧啶-2-基）苯胺
制剂类型：12．5%乳油、20%可湿性粉剂、40%悬浮剂、20%悬浮剂
理化性质：原药为无色晶体或白色或白色带微黄色结晶。能溶于有机溶剂，微溶于水 ，室温下（25℃）在水中溶解度为0.121g/L, 在25℃下熔点96.3℃（纯品），蒸气压2.2×10-3Pa(25℃)，在弱酸-弱碱性条件下稳定。 嘧霉胺的结构式

作用特点
为传统用药杀菌剂，属苯胺基嘧啶类。为当前传统药物中防治黄瓜灰霉病、番茄灰霉病、枯萎病活性较高的杀菌剂。
作用机理独特，通过抑制病菌浸染酶的产生从而阻止病菌的侵染并杀死病菌。
作用机理独特，对常用的非苯胺基嘧啶类（苯并咪唑类及氨基甲酸脂类）杀菌剂已产生抗药性的灰霉病菌有强效，主要抑制灰葡萄孢霉的芽管伸长和菌丝生长，在一定的用药时间内对灰葡萄孢霉的孢子萌芽也具有一定抑制作用。
同时具有内吸传导和熏蒸作用，施药后迅速达到植株的花、幼果等喷雾无法达到的部位杀死病菌，尤其是加入卤族特效渗透剂后，可增加在叶片和果实附着时间和渗透速度，有利于吸收，使药效更快、更稳定，目前国内合成成功的有41%聚砹·嘧霉胺。 此外嘧霉胺对温度不敏感，在相对较低的温度下施用不影响药效。 41%聚砹·嘧霉胺

防治对象
嘧霉胺具有保护和治疗作用，是防治灰霉病、枯萎病的一种高效、低毒杀菌剂，具有内吸传导和熏蒸作用，施药后可迅速传到植物体内各部 嘧霉胺
[2]位，有效抑制病原菌侵染酶的产生，从而阻止病菌侵染，彻底杀死病菌。与其他杀菌剂无交互抗性，而且在低温下使用，仍有非常好的保护和治疗效果。用于防治黄瓜、番茄、葡萄、草莓、豌豆、韭菜、等作物灰霉病、枯萎病以及果树黑星病、斑点落叶病等。
防治黄瓜番茄等灰霉病，在发病前或初期，每亩用40%嘧霉胺25-95g，兑水800-1200倍，亩用水量30-75kg,植株大，高药量高水量；植株小，低药量低水量，每隔7-10天用一次，共用2-3次。一个生长季节防治需用药4次以上，应与其他杀菌剂轮换使用，避免产生抗性。露地菜用药应选早晚风小、低温进行。
毒性：低毒，小鼠经口LD50为4061～5358mg/kg，大鼠经口LD50为4150～5971mg/kg，大鼠经皮LD50大于5000mg/kg。对家兔眼睛和皮肤无刺激性，在实验剂量内对动物无致畸、致癌、致突变作用。

注意事项
存储
贮存时不得与食物、种子、饮料混放。

使用
晴天上午8时至下午5 时、空气相对湿度低于 65%时使用；气温高于28度时应停止施药。

解毒参考方法
1、用药时如果感觉不适，立即停止工作，采取急救措施，并携标签送医就诊。
2、皮肤接触：立即脱掉被污染的衣物，用肥皂和大量清水彻底清洗受污染的皮肤。
3、眼睛溅药：立即将眼睑翻开，用清水冲洗10-15分钟，再请医生诊治。
4、发生吸入：立即将吸入者转移到空气新鲜处，请医生诊治。
5、误服：立即携带标签，送医就诊。无特效解毒剂，请对症治疗。

pyrimethanil
Fungicide
FRAC 9, D1; anilinopyrimidine

NOMENCLATURE
Common name pyrimethanil (BSI, draft ISO)
IUPAC name N-(4,6-dimethylpyrimidin-2-yl)aniline
Chemical Abstracts name 4,6-dimethyl-N-phenyl-2-pyrimidinamine
CAS RN [53112-28-0] Development codes SN 100309 (Schering); ZK 100309

PHYSICAL CHEMISTRY
Mol. wt. 199.3 M.f. C12H13N3 Form Colourless crystals. M.p. 96.3 ºC V.p. 2.2 mPa (25 ºC) (OECD 104) KOW logP = 2.84 (pH 6.1, 25 ºC) Henry 3.6 ´ 10-3 Pa m3 mol-1 (calc.) S.g./density 1.15 (20 ºC) Solubility In water 0.121 g/l (pH 6.1, 25 ºC). In acetone 389, ethyl acetate 617, methanol 176, dichloromethane 1000, n-hexane 23.7, toluene 412 (all in g/l, 20 °C). Stability Stable in water within the relevant pH range. Stable for 14 d at 54 ºC. pKa 3.52, weak base (20 °C) (OECD 112)

COMMERCIALISATION
History Reported by G. L. Neumann et al. (Proc. Br. Crop Prot. Conf. - Pests Dis., 1992, 1, 395). Introduced by Schering (now Bayer CropScience). Some rights, primarily in Europe, acquired by BASF AG in 2003.

APPLICATIONS
Biochemistry Proposed inhibitor of methionine biosynthesis, leading to inhibition of the secretion of enzymes necessary for infection. Mode of action Protectant (in Botrytis) and both protective and curative action (in Venturia). Uses Control of grey mould (Botrytis cinerea) on vines, fruit, vegetables and ornamentals. Control of leaf scab (Venturia inaequalis or V. pirina) on pome fruit. Phytotoxicity May be phytotoxic in closed systems at ³80% r.h. on certain species. Formulation types SC. Selected products: 'Mythos' (Bayer CropScience, BASF); 'Scala' (Bayer CropScience, BASF)

OTHER PRODUCTS
Mixtures: 'Clarinet' (+ fluquinconazole) (Bayer CropScience, BASF); 'Vision' (+ fluquinconazole) (Bayer CropScience, BASF); 'Walabi' (+ chlorothalonil) (Bayer CropScience, BASF)

ANALYSIS
Product and residue analysis by hplc. Details available from Bayer CropScience and BASF AG.

MAMMALIAN TOXICOLOGY
Oral Acute oral LD50 for rats 4150-5971, mice 4665-5359 mg/kg. Skin and eye Acute percutaneous LD50 for rats >5000 mg/kg. Non-irritating to skin and eyes (rabbits), and not a skin sensitiser (guinea pigs). Inhalation LC50 (4 h) for rats >>1.98 mg/l. NOEL (2 y) for rats 20 mg/kg b.w. daily. ADI 0.17-0.2 mg/kg. Other Negative in mutagenicity tests, and non-teratogenic in rats and rabbits. Toxicity class WHO (a.i.) U; EPA (formulation) IV ('Scala' and 'Mythos')

ECOTOXICOLOGY
Birds Acute oral LD50 for mallard ducks and bobwhite quail >2000 mg/kg. LC50 (5 d) for mallard ducks and bobwhite quail >5200 mg/kg diet. Fish LC50 (96 h) for mirror carp 35.4, rainbow trout 10.6 mg/l. Daphnia LC50 (48 h) 2.9 mg/l. Algae EbC50 (96 h) 1.2 mg/l. Bees LD50 (oral and contact) >100 mg/bee. Worms LC50 (14 d) for earthworms 625 mg/kg dry soil. Other beneficial spp. Classified as harmless to a range of beneficials.

ENVIRONMENTAL FATE
Animals Rapidly absorbed, extensively metabolised and rapidly excreted in all species examined. No evidence of accumulation, even on repeated dosing. Metabolism proceeds by oxidation to phenolic derivatives which are excreted as glucuronide or sulfate conjugates. Plants Little metabolism occurs in fruit; residues at maturity consist essentially of unchanged parent compound only. For this reason, a crop residue monitoring method has been developed for the direct determination of pyrimethanil itself. Soil/Environment DT50 in laboratory studies 27-82 d; field studies indicate rapid degradation, DT50 7-54 d. Koc 265-751. Low potential for leaching to groundwater; field studies show minimal movement of pyrimethanil into deeper soil layers. Pyrimethanil disappears rapidly from surface water and moderately adsorbs to the sediment, from which it is further degraded.