3-二氟甲基-1-甲基吡唑-4-羧酸肟酯衍生物的合成及抑菌活性

为发现具有高抑菌活性的先导化合物,结合本课题组前期研究,设计并合成了18个新型3-二氟甲基-1-甲基吡唑-4-羧酸肟酯衍生物,其结构均经核磁共振氢谱、碳谱及高分辨质谱分析确证,化合物 9g 的单晶衍射结果证明肟酯的构型为E式。离体生物活性测定结果表明,目标化合物在50 μg/mL下对番茄灰霉病菌 Botrytis cinerea、苹果树腐烂病菌Valsa mali 和小麦全蚀病菌Gaeumannomyces graminis均表现出一定的抑制活性,其中化合物 9d 对苹果树腐烂病菌、 9r 对小麦全蚀病菌的EC₅₀值分别为0.89 μg/mL和3.34 μg/mL,表现出比先导化合物 L1 (E-2-氯-6-氟苯甲醛-O-(1-甲基-3-苯基-1H-吡唑-5-羰基)肟)和肟菌酯更优或相似的抑菌活性。     

5-甲基异噁唑-4-甲酸肟酯衍生物的合成及抑菌活性

异噁唑是具有较好活性的五元杂环,本文设计并合成了15个5-甲基异噁唑-4-甲酸肟酯类新化合物,利用核磁氢谱、核磁碳谱和高分辨质谱对其结构进行确证,并测试了其对番茄灰霉病菌Botrytis cinerea、水稻纹枯病菌Rhizoctonia solani、苹果树腐烂病菌Valsa mali和小麦全蚀病菌Gaeumannomyces graminis的离体抑菌活性。结果表明,在50μg/mL下,目标化合物对供试病原菌均有一定的抑菌活性,其中化合物5g对番茄灰霉病菌的抑制活性优于先导化合物L1和肟菌酯,EC₅₀值为1.95μg/mL。     

(E)-α-氧代环十二酮肟醚的合成及其杀菌活性

由环十二酮先后经肟化和醚化反应合成了一系列(E)-α-氧代环十二酮肟醚,收率59%~92%。其结构经IR,1H NMR,13C NMR确证。以化合物5o为代表,通过单晶X-衍射分析确证了其构型为E式。生物测定结果表明,多数化合物对蔬菜苗期立枯病菌、黄瓜黑星病菌、黄瓜炭疽病菌、瓜类灰霉病菌,棉花枯萎病菌和芦笋茎枯病菌的生长有良好的抑制活性。如5k对上述6种病原菌的EC50值分别为13、9、12、19、14、3mg/L。     

(Z)-2-(1H-1,2,4-三唑-1-基)-1-(2,3,4-三甲氧基苯)乙酮肟酯的合成和结构表征

合成了8个(Z)-2-(1H-1,2,4-三唑-1-基)-1-(2,3,4-三甲氧基苯)乙酮肟酯新化合物,经元素分析、IR、1H NMR、MS对其结构进行了表征。讨论了目标化合物的合成方法和立体化学结果。     

12-(取代苯氧异丁酰氧亚氨基)-1,15-十五内酯的合成及除草活性

通过取代苯氧异丁酸与12-(羟基亚氨基)十五内酯的反应,合成了取代苯氧异丁酰氧亚氨基十五内酯,并测定了其对苋菜的除草活性。所有化合物均经过1H NMR、13C NMR和元素分析确证。初步的生物活性测定结果表明,目标化合物 Ⅲa~Ⅲd 的EC50值分别为34.570、46.492、55.385、50.114 mg/L,其活性比对照药剂2,4-D(117.325 mg/L)高,而比苯磺隆(22.381 mg/L)低。     

2-氰基-3-(6-氯-3-吡啶甲基)胺基-3-脂肪胺基丙烯腈的合成与生物活性

以 3-氨甲基吡啶和 2 -氯 - 5 -氨甲基吡啶为原料先与 2 -氰基 - 3,3-二甲硫基丙烯腈反应 ,产物不经分离再与脂肪胺反应合成了 14个未见文献报道的开环类吡虫啉结构类似物。所有目标化合物均经元素分析、1H NMR确证。初步活性测试结果表明含硫化合物的杀虫活性优于双氨基化合物 ,其中 4 c对豆蚜的抑制率最高达 87.6%。     

(E)-O-芳酰基-α-氧代环十二酮肟的合成及除草活性

以环十二酮为原料 ,制得中间体 (E) -α-氧代环十二酮肟 (Ⅳ)后 ,经酰化合成了九个 (E) - O-芳酰基 -α-氧代环十二酮肟 (Ⅴ) ,它们的结构得到元素分析、IR和 1HNMR的确证。生测结果表明 ,部分化合物具有良好的除草活性。对活性较高的 3还通过精密毒力测定 ,求得 IC50 值。中间体 在贝克曼反应条件下发生断裂反应生成 11-氰基十一酸 (Ⅶ) ,证实了 具有 (E) -构型的结构特征。     

新型N-芳基-2-((5-((4,6-二甲基嘧啶-2-基)硫甲基)-1,3,4-噻二唑-2-基)硫)乙酰胺类化合物的合成及杀菌活性

为寻找新型杂环活性化合物,通过活性亚结构拼接,以硫脲和乙酰丙酮为起始原料合成4,6-二甲基嘧啶-2-硫醇,随后经酯化、肼化、环化和缩合反应,设计并采用微波辅助合成了10个新型N-芳基-2-（（5-（（4,6-二甲基嘧啶-2-基）硫甲基）-1,3,4-噻二唑-2-基）硫）乙酰胺类化合物,其结构通过核磁共振氢谱和碳谱、红外光谱、质谱及元素分析确认。初步生物活性测试结果表明,在50 mg/L下,大部分目标化合物对植物病原真菌具有一定的抑制活性,其中化合物8h对黄瓜炭疽病菌Colletotrichum orbiculare的抑制率达77.3%。     

5-(羟基亚甲基)-2,4-咪唑啉二酮酯的合成及除草活性

在实验室原有的AdSS酶抑制剂研究工作基础上,以丝氨酸为原料设计合成了9个未见文献报道的2,4-咪唑啉二酮酯类化合物,其结构经核磁共振氢谱、红外光谱、元素分析或质谱等验证。初步生物活性测试结果表明,化合物 3g 在质量浓度200 μ g/mL下对拟南芥Arabidopsis thaliana的发芽抑制率达到70%,表现出一定的除草活性。     

3-氯-1-(2-吡啶基)-3,5-二甲基-吡唑-4-乙酰胺基-5-三氟甲基-苯基-1,3,4-噻二唑的合成研究

寻找具有较高活性的含1,3,4-噻二唑杂环衍生物。根据活性拼接原理,分别将吡唑,1,3,4-噻二唑引入到同一分子中,用1H NMR 13C NMR将其结构进行表征。所合成的化合物首次被报道。试验表明,该化合物显示出显著的除草活性。可以将其作为先导化合物,设计合成更多的类似物来探索新型、高效低毒和对非靶标生物安全的新型除草剂。     

吡啶衍生物研究(II)3-(4-吡啶基)-4-烃基-1,2,4-三唑啉-5-硫酮的合成及生物活性

本文研究合成了十七个 3- (4-吡啶基 ) - 4 -烃基 - 1,2 ,4 -三唑啉 - 5-硫酮化合物 ,并归属了它们的1HNMR和 13 CNMR。生物活性测定结果表明 ,合成化合物均具有一定的杀菌和除草活性 ,但植物生长促进活性较差     

Effects of ametryn [2-(ethylamino)-4-(isopropylamino)-6-(methylthio)-s-triazine] on nitrate reductase activity and nitrite content of wheat (Triticum aestivum L.)

The objectives of this study were to show that: (a) a herbicide, such as ametryn, which interferes with the photosynthetic electron transport system, causes nitrite to accumulate in illuminated leaves and (b) that nitrite is toxic and contributes to the herbicidal damage and death of the plant. Tests were conducted on wheat seedlings grown on 5 mM nitrate, 5 mM ammonia, and zero nitrogen. Ametryn treatment decreased in vivo and in vitro nitrate reductase activity (NRA) within a 26-hr period. In vivo NRA decreased more rapidly than in vitro NRA. Compared with control tissue, only 3% in vivo NRA remained at the end of 26 hr. The in vivo assay conducted in light confirmed the inhibition of photosynthetic electron flow by ametryn within the leaf tissue. Nitrate-grown, ametryn-treated plants accumulated nitrite and, after 10 days were the only plants that were completely desiccated and dead. Ammonia- and zero-nitrogen, ametryn-treated plants did not accumulate nitrite, were only partially chlorotic after the 10-day period, and were still living. Low levels of NO_(X) (NO₂ and/or NO) emissions were demonstrated by nitrate-grown ametryn-treated plants.     

2-氰基-3-取代胺基(或甲硫基)-3-(2-氯-5-吡啶甲胺基)-丙烯酸酯类化合物的合成及生物活性

作者曾模拟新烟碱类杀虫剂的化学结构,合成了一系列含2-氯-5-吡啶甲基的双氰基取代烯酮缩胺类化合物,并对其进行了生物活性测定,发现部分化合物显示了较好的杀虫和除草活性[1],特别是除草活性引起我们的兴趣。为进一步研究此结构类型的化合物的合成及生物活性,我们以酯基替代前文所述化合物中的一个氰基,并保留新烟碱杀虫剂nitenpyram类似物的骨架[2]。由于这种结构与作为光合作用光系统II(PSII)电子传递抑制剂的氰基丙烯酸酯类化合物很相似[3],该类化合物可能会有更好的除草效果。我们依此设计,合成了2-氰基-3-(2-氯-5-吡啶甲胺基)-3-甲…     

The degradation of (Z)- and (E)-1,3-dichloropropenes and 1,2-dichloropropane in soil

The degradation in soil of the major constituents of a 1,3-dichloropropene-1,2-dich-loropropane nematicide has been studied under laboratory and outdoor conditions. In sealed glass containers, ( Z)- and ( E)-1,3-dichloropene- 2-¹⁴C were converted in soil into the corresponding 3-chloroallyl alcohols and these alcohols were in part strongly bound to the soil. The ( Z)- and ( E)-3-chloroacrylic acids were also found as minor products. More polar products were detected and these released the chloroacrylic acids in 20–30% yield upon hydrolysis. Although the 1,3-dichloropropenes were lost by volatilisation from soil stored in open glass jars outdoors, they also underwent degradation to the same products that were detected in sealed containers. There was evidence of only slight degradation of 1,2-dichloropropane- 2-¹⁴C (4 % or less of the applied radioactivity remained unextracted from a loam soil after 5 months). When soil treated with the 1,2-dichloropropane was stored outdoors in an open glass container, less than 1 % of the original radiolabel remained in the soil after 10 days under these conditions due to volatilisation of the applied material. In a separate experiment potatoes were grown in soil 6 months after treatment with a mixture of both ( Z)- and ( E)-1,3-dichloropropene- 2-¹⁴C and 1,2-dichloropropane- 2-¹⁴C. Although 5 % of the applied radiolabel remained in the soil at potato harvest the potato tubers contained only a very small residue (0.007 mg/kg).     

Insecticidal activity of the pyrimidine nucleoside analogue (E)-5-(2-bromovinyl)-2'-deoxyuridine (BVDU)

The insecticidal activity of the antiherpetic agent (E)-5-(2-bromovinyl)-2'-deoxyuridine (BVDU) was assessed in in vivo assays against the fall armyworm, Spodoptera frugiperda (JE Smith) (Lepidoptera, Noctuidae). BVDU, mixed into an artificial diet, caused a variety of effects, depending on the concentration used. Compared with controls, food intake was lower, larval growth was retarded and larval development was prolonged. The treated larvae formed smaller pupae and the hatching moths often showed morphogenetic defects. A higher mortality could be found in larval and pupal stages and was generally caused by moult disruption. A choice assay showed that BVDU has very slight feeding-deterrent properties, which only partly explain the toxic effects. The agent most probably acts through its cytostatic activity that has been described previously using cell lines of different insect species.     

Photochemical behaviour of dichlorprop [(+/-)-2-(2,4-dichlorophenoxy)propanoic acid] in aqueous solution

Aqueous solutions of dichlorprop were irradiated under different conditions of pH, wavelength and oxygenation. The photochemical behaviour was found to be complex and many photoproducts were formed. However, at low concentrations the main photoproducts were 4-chloropyrocatechol, 2-chlorophenol, 4-chlorophenol and 2,4-dichlorophenol. Some other photoproducts were identified, namely 2-(4-chloro-2-hydroxyphenoxy)propanoic acid, 2-(3,5-dichloro-2-hydroxyphenyl)propanoic acid and 2,4-dichlorophenyl acetate. From comparison with results previously obtained with mecoprop [2-(4-chloro-2-methylphenoxy)propanoic acid] it appears that the presence of a chlorine atom in position 2 on the ring strongly modifies the photochemical behaviour.     

Synthesis and herbicidal activities of novel 3-(substituted benzyloxy or phenoxy)-6-methyl-4-(3-trifluoromethylphenyl)pyridazine derivatives

BACKGROUND: 4‐(3‐Trifluoromethylphenyl)pyridazine represents a new series of compounds with bleaching and herbicidal activities. RESULTS: A total of 43 novel 3‐(substituted benzyloxy or phenoxy)‐6‐methyl‐4‐(3‐trifluoromethylphenyl)pyridazine derivatives were synthesised, and their bleaching and herbicidal activities were evaluated through Spirodela polyrrhiza and greenhouse tests. Some compounds exhibited excellent herbicidal activities, even at a dose of 7.5 g ha^?1. CONCLUSION: The results showed that a substituted phenoxy group at the 3‐position of the pyridazine ring and the electron‐withdrawing group at the para ‐position on the benzene ring were essential for high herbicidal activity. Copyright © 2011 Society of Chemical Industry     

Determination of residues of 1-(2-cyano-2- methoxyiminoacetyl)-3-ethylurea (DPX-3217) by gas-liquid chromatography

Residues of the fungicide 1-(2-cyano-2-methoxyiminoacetyl)-3-ethylurea (DPX-3217) in grapes, potatoes, tomatoes and wine were determined by initial extraction with ethyl acetate, clean-up by liquid-liquid partitioning and adsorption chromatography, and final determination by gas-liquid chromatography with a nitrogen-selective detector. The sensitivity of the method was 0.04 mg kg^?1 based on 50-g samples. Recoveries of the compound added to untreated substrates averaged approximately 92% in the range of 0.04-5.0 mg kg^?1.     

Design, synthesis and anticoccidial activity of a series of 3-(2-(2-methoxyphenyl)-2-oxoethyl) quinazolinone derivatives

A series of 3-(2-(2-methoxyphenyl)-2-oxoethyl) quinazolinone derivatives were designed and synthesized as anticoccidial agents by modifying the quinazoline ring of febrifugine. All the compounds were biologically evaluated according to the ACI method, and four of them exhibited anticoccidial activity against Eimeria tenella in the chicken at a dose of 9 mg/kg. Compound 5e shows ACI value at 173.2 and is as potent as decoquinate. These data suggest that 5e possesses high anticoccidial activity and may serve as a lead compound for the development of anticoccidial drugs in the future.