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1.
本文以丙二酸二乙酯为原料,在乙醇钠条件下与氯乙酸乙酯反应生成乙烷-1,2,2-三羧酸乙酯,再用硼氢化钠还原得2-羟基-1,4-丁二醇,在对甲苯磺酸的催化下脱水环合成3-羟甲基四氢呋喃,再与对甲苯磺酰氯、三乙胺反应生成3-四氢呋喃甲基对甲苯磺酸酯;甲醛水溶液、甲基硝基胍、甲胺水溶液在乙醇中反应生成1,5-二甲基-2-硝基亚胺六氢-1,3,5-三嗪;3-四氢呋喃甲基对甲苯磺酸酯与1,5-二甲基-2-硝基亚胺六氢-1,3,5-三嗪反应生成呋虫胺。  相似文献   

2.
陈宏 《植物检疫》1993,7(1):22-23
信息素(Pheromone)是一类由昆虫个体释放于体外,以调节或诱发同种其它个体行为反应的化学物质,它包括性信息素,聚集素、报警素和示踪素等。从雄性棉铃象中已分离鉴定出由4种成分组成的性信息素和聚集素:(+)顺2-异丙烯基-1-甲基环丁基乙醇、顺-3,3-二甲基-Δ~(β)-环己基乙醇、顺-3,3-二甲基-Δ(α)-环己基乙醛和反-3,3-二甲基-Δ~(α)-环己基乙醛。其中的第一种化合物必须与第二  相似文献   

3.
以4-甲氧基-2-硝基苯胺(1)为起始原料,经烷基化、硝基还原和环化反应制得中间体1-异丙基-5-甲氧基苯并咪唑酮(4),再经N-酰化反应得到24个1-异丙基-3-酰基-5-甲氧基苯并咪唑酮衍生物(5a~5x),通过核磁共振氢谱及元素分析对其结构进行了表征。初步抑菌活性测定结果表明,所有目标化合物对番茄灰霉病菌Botrytis cinerea的孢子萌发均有不同程度的抑制作用,其中5i(2-乙基丁酰基衍生物)和5q(2-甲基苯甲酰基衍生物)活性最高,在50 μg/mL时的抑制率分别为95.9%和93.4%。  相似文献   

4.
取代双吡唑类化合物的合成及杀虫活性   总被引:1,自引:1,他引:0  
以3-氯苯肼盐酸盐( 1 )和1,1,3,3-四甲氧基丙烷( 2 )为起始原料,经环化、Vilsmeier反应得1-(3-氯苯基)-1H-吡唑-4-甲醛( 4);(4 )与3-三氟甲基苯乙酮( 5 )经Claisen-Schmidt缩合反应得取代芳基烯酮类化合物( 6 ),再与水合肼发生环化反应得3-(3-三氟甲基苯基)-5-(3-氯苯基-1H-吡唑)-4,5-二氢吡唑( 7),其与取代异氰酸酯 作用,制得15个未见文献报道的结构新颖的取代双吡唑类化合物。利用核磁共振氢谱(1H NMR)和质谱(MS)对其结构进行了表征。初步生物活性测定结果表明,在 500 mg/L 质量浓度下,部分化合物对小菜蛾Plutella xylostella的致死率达100%,而对苜蓿蚜Aphis medicaginis、稻褐飞虱Nilaparvata lugens、朱砂叶螨Tetranychus cinnabarinus均无杀虫活性。  相似文献   

5.
以二氟乙酰乙酸乙酯和原甲酸三乙酯为起始原料,经亲核取代、环化、水解、氯代和酰化反应得到N-(1-甲基-2-羟乙基)-3-二氟甲基-1-甲基-1 H -吡唑-4-酰胺(4),4与取代异氰酸酯作用,合成了10个未见文献报道的二氟甲基取代吡唑甲酰胺类衍生物,其结构均经过1H NMR和MS分析确证。初步生物活性测试结果表明,在50 mg/L下,目标化合物 ZJ-3、ZJ-5、ZJ-7、ZJ-8 对瓜类炭疽病菌、瓜类灰霉病菌和水稻纹枯病菌具有一定的杀菌活性。  相似文献   

6.
根据拼合原理,将1,3,4-噻二唑基引入羟基苯甲醛设计成新颖结构的胺基甲基苯酚,并研究其合成工艺。寻求制备具有杀菌活性的化合物2-[5-(4-甲氧基苯基)-(1,3. 4)-噻二唑基-6-异丙基]胺基甲基苯酚。以邻异丙基水杨醛和2-氨基-5-(4-甲氧基)-苯基-(1,3. 4)噻二唑为起始原料,经过缩合、还原反应一锅法制得目标化合物2-[5-(4-甲氧基苯基)-(1,3. 4)-噻二唑基-6-异丙基]胺基甲基苯酚。在优化的条件下,反应总收率为75. 8%,纯度为99. 1%。该工艺简单经济,条件温和,一锅法合成工艺减少了溶剂的用量和废物排放量,收率较高。  相似文献   

7.
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%。  相似文献   

8.
以1-甲基-3-二氟甲基吡唑-4-甲酸为原料,经过1-甲基-3-二氟甲基吡唑-4-甲酰氯与相应的氨基苯并杂环类、芳胺类化合物反应,得到了14个未见文献报道的吡唑-4-甲酰胺类化合物(6a~6g、7a~7g),其结构均通过1H NMR、MS和IR表征。抑菌活性测试结果表明,在100 mg/L下,目标化合物对供试植物病原菌均有不同程度的抑制作用,其中7a~7g的抑菌活性较高,部分对苹果炭疽病菌的抑制率在90%以上。  相似文献   

9.
设计合成了一系列结构新颖的嘧啶联吡唑甲酰胺类化合物5a~5o,其结构均经过1H NM R和MS分析确证。初步生物活性测试结果表明:在有效成分150 g/hm2剂量下苗后茎叶喷雾处理时,化合物(R)-N-[1-(4-氯苯基)乙基]-3-二氟甲基-1-(4,6-二甲氧基嘧啶-2-基)-1H-吡唑-4-甲酰胺(5c)、N-[1-(4-氯苯基)乙基]-1-(4,6-二甲氧基嘧啶-2-基)-N-甲基-3-三氟甲基-1H-吡唑-4-甲酰胺(5i)和N-[1-(4-氯苯基)乙基]-1-(4,6-二甲氧基嘧啶-2-基)-3-三氟甲基-1H-吡唑-4-甲酰胺(5k)对繁缕Stellaria media的抑制率高达90%以上;而同样剂量下苗前土壤喷雾处理时,化合物N-[1-(4-氯苯基)乙基]-3-二氟甲基-1-(4,6-二甲氧基嘧啶-2-基)-1H-吡唑-4-甲酰胺(5b)和5c对繁缕的抑制率达100%。该类结构化合物有望作为除草先导化合物进行开发。  相似文献   

10.
从二硫代磷酸二乙酯钠盐或O,O-二乙基硫代磷酰氯出发 ,经酯化、去烷基化反应得到相应的硫代或二硫代铵盐 ,分别与 2 -氯 - 5 -氯甲基吡啶反应得产物 2 a~ 2 c。从 O-乙基硫代磷酰二氯或苯基硫代膦酰二氯出发 ,先与取代苯酚或甲胺反应 ,然后与 2 -氯 - 5 -羟甲基吡啶反应得到产物 2 d~ 2 k和 2 m~ 2 u。O-乙基 - S-丙基二硫代磷酰氯、O-乙基硫代磷酰二氯和苯基硫代膦酰二氯与 2 -氯 - 5 -羟甲基吡啶反应分别得产物 2 l、2 v和 2 w。所合成的 2 3个新化合物对9种植物病菌的离体及活体杀菌活性测试表明 ,其中一些化合物对水稻稻瘟病和水稻纹枯病有一定活性 ,个别化合物活性很好 ,但对其它病菌的活性均较低  相似文献   

11.
Metabolism of [phenyl-14C] and [(2,5) pyrrolidine-14C] cisanilide was investigated in vitro with microsomal preparations from rat liver. Microsomal activity was associated with a mixed-function oxidase system that required O2 and NADPH and was inhibited by CO. Two major ether-soluble metabolites were isolated. They were identified as primary oxidation products: 2-hydroxy-2,5-dimethyl-1-pyrrolidinecarboxanilide (A) and 4′-hydroxy-2,5-dimethyl-1-pyrrolidinecarboxanilide (B). Minor ether-soluble metabolites were also isolated. Precursor product studies and qualitative thin layer chromatography analysis of [pyrrolidine-14C] and methylated [phenyl-14C] hydrolysis products suggested that these metabolites were secondary oxidation products formed from metabolites A or B. One of these metabolites appeared to be the dihydroxy product 2,4′-dihydroxy-2,5-dimethyl-1-pyrrolidinecarboxanilide. Crude microsomal preparations (postmitochondrial supernatant fractions) also formed small quantities (<10%) of polar metabolites. Enzyme hydrolysis with β-glucuronidase (Escherichia coli) indicated that approximately 50% of these metabolites were glucuronides. Similarities and differences in cisanilide oxidation in vivo in plants and in vitro with rat liver microsomal preparations were discussed.  相似文献   

12.
Major methanol-soluble metabolites of cisanilide (cis-2,5-dimethyl-1-pyrrolidinecarboxanilide) were isolated from excised, pulse-treated carrot and cotton leaves. They were identified as O-glucoside conjugates of primary aryl and alkyl oxidation products, 2,5-dimethyl-1-pyrrolidine-4-hydroxycarboxanilide and 2,5-dimethyl-3-hydroxy-1-pyrrolidinecarboxanilide. Comparative studies with carrot and cotton cell cultures showed similar initial pathways of cisanilide metabolism. Time-course studies with [14C-pyrrolidine]- and [14C-phenyl]cisanilide showed little, if any, cleavage of the herbicide molecule in either excised leaves or cell cultures. Quantitative differences in the metabolism of cisanilide by cell cultures and excised leaves included; a reduced capacity of cell cultures to form secondary glycoside conjugates and an increased ability of cell cultures to form methanol-insoluble residues.  相似文献   

13.
New esterase substrates were synthesized using cis-, trans- and cis-trans-permethrinic acid chloride and then used to measure pyrethroid-cleaving enzymes in insects. The new substrates, namely cis-, trans- and cis-trans-7-coumaryl permethrates (7-CP), show a structure very similar to permethrin insecticide and yield fluorescent products on hydrolysis. These substrates were hydrolyzed by a commercial porcine preparation that provided esterase-specific activity, and were stable at different pH values (5.2-7.8). Studies made with house fly, Musca domestica (L.), homogenates showed that these compounds are appropriate for determining pyrethroid hydrolysis activity on individual insects. The measured activity of house fly esterase was 870 relative fluorescence units (RFU) min(-1) with cis-7-CP as substrate, 1117 RFU min(-1) with trans-7-CP as substrate and 1423 RFU min(-1) with cis-trans-7-CP as substrate. The fluorescent substrates for pyrethroid-cleaving esterases described in this paper have advantages over methods already given in the literature. They are substrates with structures very similar to pyrethroids, the cleavage of which can be followed by an increase in fluorescence emission at 440 nm; it takes only about 5 min to measure the reaction, and moreover the high sensitivity of the fluorescence technique allows the quantification of esterase activity on individual insects.  相似文献   

14.
The metabolism of cis-2,5-dimethylpyrrolidine-1-carboxanilide was studied in rats, rabbits, guinea-pigs and mice. The major metabolite in all species was cis-4′-hydroxy-2,5-dimethylpyrrolidine-1-carboxanilide, both free and as glucuronide and sulphate conjugates. About 95% of the compound was absorbed from the gut; over a 3-day period, about 50% of the administered dose was excreted in urine and about 27% in faeces.  相似文献   

15.
为了获得直丝紫链霉菌Streptomyces rectiviolaceus A8最佳发酵水平,并初步确定其代谢生物活性物质以及对水稻纹枯病的防控效果。本研究通过碳、氮单因素试验,正交试验和发酵条件的优化,确定其最佳的发酵条件;通过气相色谱-质谱技术(GC-MS)对菌株A8产生的活性物质进行初步检测,将鉴定出的不同组分以立枯丝核菌Rhizoctonia solani和蜡状芽胞杆菌Bacillus cereus作为指示菌进行生物活性测定试验;同时在大田开展菌株A8对水稻纹枯病的生防效果研究。结果显示菌株A8的最佳发酵配方为:可溶性淀粉3%,黄豆粉0.6%,酵母膏0.4%,NaCl 0.05%,K2HPO4·3H2O 0.05%,MgSO4·7H2O 0.05%,FeSO4·7H2O 0.001%;最佳发酵条件:装液量100~200 mL/500 mL,接种量3%~7%,培养温度28℃~31℃,初始pH 7.0~8.0;通过气相色谱-质谱联用技术对菌株A8发酵液粗提物进行了分离和鉴定,共鉴定出26个化合物,其中3-甲基-1,2-环戊二酮、1,2,4,5-四甲基苯和二氢-3-亚甲基-2,5-呋喃二酮对立枯丝核菌的抑菌率达到70%以上,二氢-3-亚甲基-2,5-呋喃二酮、2-呋喃羧酸,酰肼、邻苯二酚和3-甲基-1,2-环戊二酮对蜡状芽胞杆菌的抑菌作用较强,该放线菌具有潜在的同时抑制真菌和细菌的作用,对开发广谱生防制剂提供很好的材料。田间防效试验结果表明,菌株A8对水稻纹枯病有一定的防效,防治效果与枯草芽胞杆菌BT205相当。  相似文献   

16.
以对氯苯肼为原料经环合、氯化,合成1-(4-氯苯基)-3-吡唑醇。本文研究了其合成工艺和投料比、反应温度、反应时间,催化剂用量和溶剂种类对收率的影响。用IR、1HNMR表征了其结构,在最优条件下,1-(4-氯苯基)-3-吡唑醇合成的总收率为68.35%,含量为98.5%,该路线简单经济,条件温和,收率高,适合工业化生产。  相似文献   

17.
The stability of the chloroneb fungicide (1,4-dichloro-2,5-dimethoxybenzene) and its principal degradation product, 2,5-dichloro-4-methoxyphenol (DCMP), was tested in the presence of individual soil microorganisms. Both the fungicide and DCMP were unaltered in liquid shake cultures of the organisms when growth was minimal or static. However, in nutrient broth where active microbial growth was supported, several organisms converted chloroneb to DCMP and/or DCMP to chloroneb. Of 23 organisms grown in the presence of 5 μg chloroneb/ml, 13 demethylated the fungicide to produce DCMP. Liquid shake cultures of Fusarium spp. were most active in this respect, converting more than 50% of the chloroneb to DCMP in 5 days. When grown in the presence of 5 μg DCMP/ml, 8 organisms, especially Trichoderma viride and Mucor ramannianus, converted up to 20% of the DCMP to chloroneb. Cephalosporium gramineum, Rhizoctonia solani, Mucor ramannianus and Fusarium fungi could both methylate and demethylate DCMP to produce chloroneb and 2,5-dichlorohydroquinone, respectively. Microbial synthesis of chloroneb from DCMP, its principal degradation product, may account in part for the relative stability and long term effectiveness of the fungicide in soil.  相似文献   

18.
ABSTRACT A survey was conducted to evaluate differences in fatty acid methyl ester (FAME) profiles among strains of Pantoea ananatis, causal agent of center rot of onion (Allium cepa), isolated from 15 different onion cultivars in three different sites in Georgia. Differences in FAME composition were determined by plotting principal components (PCs) in two-dimensional plots. Euclidean distance squared (ED(2)) values indicated a high degree of similarity among strains. Plotting of PCs calculated from P. ananatis strains capable of growing on media amended with copper sulfate pentahydrate (200 mug/ml) indicated that copper-tolerant strains grouped into tight clusters separate from clusters formed by wild-type strains. However, unlike copper-sensitive strains, the copper-tolerant strains tended to cluster by location. A total of 80, 60, and 73% of the strains from Tift1, Tift2, and Tattnall, respectively, exhibited either confluent growth or partial growth on copper-amended medium. However, all strains were sensitive to a mixture of copper sulfate pentahydrate (200 mug/ml) and maneb (40 mug/ml). When copper-tolerant clones were analyzed and compared with their wild-type parents, in all cases the plotting of PCs developed from copper-tolerant clones formed tight clusters separate from clusters formed by the parents. Eigenvalues generated from these tests indicated that two components provided a good summary of the data, accounting for 98, 98, and 96% of the standardized variance for strains Pna 1-15B, Pna 1-12B, and Pna 2-5A, respectively. Furthermore, feature 4 (cis-9-hexadecenoic acid/2-hydroxy-13-methyltetradecanoic acid) and feature 7 (cis-9/trans-12/cis-7-octadecenoic acid) were the highest or second highest absolute values for PC1 in all three strains of the parents versus copper-tolerant clones, and hexadecanoic acid was the highest absolute value for PC2 in all three strains. Along with those fatty acids, dodecanoic acid and feature 3 (3-hydroxytetradecanoic acid/14-methylpentadecenoic acid) also had an impact on the differences observed between copper-sensitive parents and copper-resistant mutants. Finding these changes in bacterial fatty acid composition could lead to the development of a laboratory assay to identify copper-tolerant strains using gas chromatography as well as providing clues to further elucidate the mode of action of copper tolerance.  相似文献   

19.
广西防城港首次截获苜蓿黄萎病菌   总被引:1,自引:0,他引:1  
从一批进境的美国苜蓿草样品中保湿分离得到了3株与苜蓿黄萎病菌(Verticillium albo-atrum)相似的目标菌VA1、VA2、VA3.该目标菌在PDA上生长迅速,菌丝生长0.8~1.0 mm/d,2~3 d即可生成肉眼可见的菌落斑点;菌落为白色圆形,边缘规则呈圆形,菌丝较致密,气生菌丝较少,菌落中心乳白色奶冻状;培养4~5 d即后产生气生典型轮枝状分生孢子梗,7~8 d后菌落中央表面因产生休眠菌丝开始变成黑褐色至黑色,20 d后菌落的表面和背面大部分均变黑色,仍不产生微菌核和厚垣孢子.该目标菌的纯培养用V.albo-atrum特异引物Vaa1/Vaa2进行检测,PCR 扩增后得到预期330 bp的产物片段,产物序列与V.albo-atrum相应序列的相似性为100%.从而鉴定确认该目标菌为苜蓿黄萎病菌V.albo-atrum.  相似文献   

20.
The degradation of the pyrethroid insecticide cypermethrin and the geometric isomers NRDC 160 (cis-) and NRDC 159 (trans-) in three soils has been studied under laboratory conditions. Samples of the insecticides labelled separately with 14C in the cyclopropyl and benzyl rings were used. The rate of degradation was most rapid on sandy clay and sandy loam soils, 50% of the NRDC 160 and NRDC 159 applied to both soils being decomposed in 4 weeks and 2 weeks respectively. The major degradative route in all soils was hydrolysis of the ester linkage leading to the formation of 3-phenoxybenzoic acid and 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid; soil treated with the cis-isomer (NRDC 160) was found to contain both cis- and trans-isomer forms of the cyclopropanecarboxylic acid. Further degradation of these carboxylic acids was evident since 14CO2 was released from cyclopropyl- and benzyllabelled cypermethrin in amounts equivalent to 24 and 38% of the applied radioactivity over a 22 week period. A minor degradative route was ring-hydroxylation of the insecticide to give an α-cyano-3-(4-hydroxyphenoxy)benzyl ester followed by hydrolysis of the ester bond. Under waterlogged conditions the rate of hydrolysis of cypermethrin on sandy loam soil was slower than under aerobic conditions and 3-phenoxybenzoic acid accumulated in the anaerobic soil.  相似文献   

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