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1.
合成了2苯胺1 ,3 ,5三嗪的一系列衍生物 ,并评价了它们的除草活性。首先研究了三嗪环上的取代 ,结果表明4甲基6三氟甲基衍生物显示高的除草活性 ,其次研究了2苯胺4甲基6三氟甲基1 ,3 ,5三嗪的苯环取代 ,结果表明苯环上的3或4卤素衍生物显示更高的除草活性。在盆载试验中表现高除草活性的2(3氯苯胺基)4甲基6三氟甲基1 ,3 ,5三嗪和2(4氯苯胺基)4甲基6三氟甲基1 ,3 ,5三嗪 ,其PET(光合电子通道)抑制活性也比除草剂西玛津和莠去津的高。  相似文献   

2.
1前言 2H-[1,4]苯并嗯嗪-3(4H)-酮类衍生物因具有广泛的生物活性和较低的毒性被用做医药和农药的中间体,构效关系研究结果显示,此类化合物分子结构中苯环上的取代基对活性的影响至关重要。笔者在从事新农药创制研究过程中发现,将苯环上有硝基的2H-[1,4]苯并嗯嗪酸做为活性基团引入到某些具有杀虫、除草活性的化合物中,可以显著提高其生物活性。  相似文献   

3.
作为一类具有特殊结构的重要有机合成中间体,2-(取代乙炔基)苯甲醛衍生物的化学结构是由苯环、取代乙炔基和醛基三部分活性基团构成的共轭体系. 因其具有较高的反应活性,而被广泛的用于构建各种具有新颖结构的苯并碳环或苯并杂环类化合物,如苯并碳环化合物、苯并氮杂环化合物、苯并氧杂环化合物、多元苯并杂环化合物等. 本文综述了2-(取代乙炔基)苯甲醛衍生物在有机合成领域的应用,并对其发展前景进行了展望,为今后2-(取代乙炔基)苯甲醛衍生物在有机合成中的应用提供参考.  相似文献   

4.
除草剂靶酶-天冬酰胺合成酶特性及其抑制剂的研究进展   总被引:3,自引:0,他引:3  
林深源  向文胜  范志金 《农药》2006,45(6):378-380,384
天冬酰胺合成酶是2000年发现的除草剂环庚草醚靶标酶,在植物体中,天冬酰胺合成酶是催化天冬氨酸和谷胺酰氨生成天冬酰胺和谷胺酸,而天冬酰胺义是重要的运输氮化合物。现义明确天冬酰胺合成酶是由两部分组成:N基末端的两个反平行式β-折叠片层巾的楔形部分是负责水解谷氨酰胺的活性部位;C基末端负责结合Mg^2+ATP和天冬氨酸。在芳香族植物巾发现单萜化合物有抑制天冬酰胺合成酶的作用,化学合成1.4-桉树脑衍生物也有一定除草活性。  相似文献   

5.
王胜  龚银香  袁莉  汪焱钢 《化学试剂》2005,27(3):176-178
合成了8个含四唑基、苯并噻唑基、三唑并[1,5-α]嘧啶基和取代嗯二唑基的α-氯乙酰基脲,通过IR、^1HNMR和元素分析确证了其结构,初步的生物活性测试试验表明,含四唑基的α-氯乙酰基脲具有较好的除草活性。  相似文献   

6.
郑鹛  王霖  杜晓华  浦晓莺  沈宙  陈胜  徐振元 《农药》2006,45(3):165-166
由双(4-氨基-2-氯苯基)二硫醚与芳基异氰酸酯反应,合成了11个不同取代的双[(N-芳基脲基)苯基]二硫化物,结构经IR、MS和^1H NMR确定。初步的生测结果表明目标化合物3f、3k具有一定的除草活性.3i对南方粘虫具有杀虫和拒食活性,3f和3h对黄瓜白粉病有一定的抑制作用。  相似文献   

7.
芳氧苯氧丙酸酯类衍生物是一类高效防除禾本科杂草的除草剂。近年来在苯氧羧酸的苯环对位引入杂环基开发了一系列高活性的品种,如Hoechst公司开发的噻唑禾草灵和曙唑禾草灵、Dow公司开发的吡氟氯禾灵甲酯。文献报道合成这类化合物的方法是首先合成卤索取代的杂环,然后与苯氧羧酸酯发生亲核取代反应。吡唑[3,4-d]并嘧啶-4-酮具有广泛的生物活性,我们通过新方法已合成了一系列含吡唑[3,4-d]并嘧啶-4-酮的芳氧苯氧乙酸酯类衍生物,初步生物活性测定表明具有良好的除草活性。  相似文献   

8.
N—硅丙基—N—甲酰基苯胺衍生物的合成和生物活性研究   总被引:2,自引:0,他引:2  
本文研究了氯丙基硅烷和取代苯胺在二甲基甲酰胺中,有乙醇钠存在下的反应,合成了8种新的N-硅丙基-N-甲酰基苯胺衍生物和2个N-硅丙基-1,2,4-三氮唑和咪唑化合物。所得化合物均通过元素分析、IR和HNMR确证了结构。其中8个新化合物进行了杀菌活性和除草活性的测定。结果表明,它们的杀菌活性与相应的N-硅甲基-N-甲酰基苯胺衍生物同级。  相似文献   

9.
1,4-二氧喹喔啉类化合物是研究得较早的具有抗菌活性的物质,此类化合物的主要特点是低毒副作用和较明显抑菌活性,被广泛作为兽药和医药。所报道的化合物主要是1,4-二氧喹喔啉甲酸的衍生物如酯和酰胺类化合物,其醛衍生物的研究工作还少见报道,更未见该类化合物的除草活性的研究。  相似文献   

10.
为了寻求高效、安全的除草活性的化合物,设计并合成了8个2-取代-N-(7-氟-3,4-二氢-4-取代-3-氧-2H-苯并[b][1,4]噁嗪-6-基)乙酰胺类化合物,其化学结构经IR,1HNMR,LC/MS等确证。初步生物活性测定结果表明,目标化合物的除草活性并不显著。  相似文献   

11.
J. Arguello 《Electrochimica acta》2004,49(27):4849-4856
A detailed study was done of the electrochemical oxidation of some 1,4-dihydropyridine (1,4-DHP) derivatives in order to determine the influence of the substituents in the heterocyclic ring. Two types of derivatives were synthesized, namely, 3,5-(substituted)-4-(5′-nitro-2′-furyl)-1,4-DHP for series A, and 3,5-dicarboethoxy-4-(substituted or non-substituted)-1,4-DHP for series B. Voltammetry, coulometry, controlled potential electrolysis, UV-vis spectroscopy and GC-MS techniques were employed to collect data that permitted to postulate oxidation mechanisms in a protic medium. In acid media, at pH < 4, all derivatives follow oxidation mechanisms obeying the ECE sequence. However, at pH > 4, series A derivatives follow an ECEC sequence, while series B derivatives obey a DISP1 mechanism. In both cases, the uptake of proton at N-1 by the OH ion of the media was the rate-determining step.  相似文献   

12.
Substituents on cyclopentadienyl ligands significantly influence the reactivity and catalytic efficiency of their transition metal complexes. Therefore, development of synthetic methods for cyclopentadiene derivatives possessing different substituents has been in great demand. In this paper, we report new synthetic methods for multiply substituted cyclopentadienes recently developed in this group. In principle, three types of preparative methods are described. Firstly, zirconacyclopentadienes in the presence of Lewis acids react with aldehydes to afford multiply substituted cyclopentadienes, thus providing a one-pot procedure from two molecules of identical or different alkynes and one molecule of aldehyde; reaction of aluminacyclopentadienes with aldehydes also result in high-yield formation of multiply substituted cyclopentadienes. Secondly, 1,2,3,4-tetrasubstituted 1,4-dilithio- and 1,4-bis(magnesiobromo)-1,3-diene derivatives react with aldehydes or ketones via deoxygenation of the C=O moieties to afford cyclopentadiene derivatives. Thirdly, monolithio reagents, 1,2,3,4-tetrasubstituted 1-lithio-1,3-butadienes, and Grignard reagents, 1,2,3,4-tetrasubstituted 1-magnesiobromo-1,3-butadienes react with aldehydes or ketones to afford cyclopentadiene derivatives upon hydrolysis.  相似文献   

13.
The effect of electron-donor (piperidino) and electron-acceptor (cyano) groups on the absorption maxima of some diketo-pyrrolo-pyrroles in DMSO solution was investigated both experimentally and theoretically. The syntheses of push–pull substituted 3-(4-piperidinophenyl)-6-(4-cyanophenyl)-2,5-dihydropyrrolo[3,4-c]pyrrol-1,4-dione are reported for the first time; 3,6-diphenyl-2,5-dihydropyrrolo[3,4-c]pyrrol-1,4-diones substituted with either one or two piperidino or cyano groups in the para-positions of the phenyl rings were also synthesized. Whilst both types of substituent produce a bathochromic and hyperchromic shifts with respect to the parent unsubstituted compound, the influence of the piperidino group is strongest. Symmetrically substituted derivatives show well-resolved vibronic structures, while the spectra of polar, unsymmetrical compounds were poorly resolved because of strong dipole–dipole interaction with the polar solvent. The fluorescence of all compounds was intense and a significant increase in the Stokes shift of polar derivatives was another consequence of dipole–dipole interactions with the solvent in the excited state.  相似文献   

14.
Benzene and substituted derivatives (toluene, ortho-xylene, 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene, anisole), when applied in large excess, react with 1,4 diols (pentan-1,4-diol, hexan-2,5-diol, and 2,5-dimethylhexan-2,5-diol) or an oxolane (2,2,5,5-tetramethyltetrahydrofuran) in the presence of the Brønsted superacid trifluoromethanesulfonic acid (triflic acid, TFSA) to afford substituted tetralins in excellent yields with high selectivity. Reacting benzene with a small excess of alkylating agents yields octahydroanthracenes. The transformation of naphthalene with oxolane leads to a partially saturated octamethyloctahydrotetracene under similar conditions. Product formation is interpreted by intermolecular Friedel-Crafts alkylation followed by cyclialkylative ring closure.  相似文献   

15.
Erbium(III) complexes of 2-hydroxy-l,4-naphthalenedione-1-oxime and its C-3 substituted derivatives are synthesized and characterized by elemental analysis, thermogravimetric analysis, infrared spectroscopy, magnetic susceptibility measurements 2-hydroxy-1,4-naphthalenedione-1-oxime derivatives are analysed using (1)H and (13)C NMR spectroscopy. The molecular composition of the synthesized complexes is found to be [ML(3)(H(2)O)(2)]. The antimicrobial activity of these complexes is determined by well diffusion method against the target microorganisms- Staphylococcus aureus, Xanthomonas campestris, Pseudomonas aeruginosa, Candida albicans and Aspergillus niger. The antimicrobial activities of 2- hydroxy-1,4-naphthalenedione-1-oximes and their complexes are compared. It is observed that 2-hydroxy-1,4-naphthalenedione-l-oximes exhibit higher antifungal activity as compared to antibacterial activity. These activities are reduced upon complexation of these oximes with Erbium.  相似文献   

16.
A novel process for the industrial production of hydroxylated fatty acids involves epoxidation of plant oils and their derivatives, followed by catalytic epoxy ring opening in the presence of water or other hydrogen donors, such as alcohols, diols, and amines. Depending on the starting material, epoxidation followed by opening of the oxirane ring leads to fatty acids that contain vicinal diol groups or to other substituted hydroxylated fatty acid derivatives. As an example for the preparation of a substituted hydroxylated fatty acid derivative, the reaction of epoxidized rapeseed oil with monobutylamine as hydrogen donor is described. Apart from the intended formation of hydroxyl groups with vicinal aminoalkyl groups, partial aminolysis of the ester compound was also observed. Another example describes the reaction of epoxidized rapeseed oil with different molar proportions of 1,4-butanediol as hydrogen donor. Depending on the molar proportion of the hydrogen donor, interesterification, or intermolecular ether formation were observed as side reactions. The properties of various technical hydroxylated fatty acids and their derivatives, prepared according to this novel process, are given, and potential applications of these products are suggested.  相似文献   

17.
A series of novel coumarin based chalcones were synthesized by the classical crossed aldol condensation reaction of 8-acetyl-1,4-diethyl-1,2,3,4-tetrahydro-7H-pyrano[2,3-g]quinoxalin-7-one and various substituted benzaldehydes. These novel ketocoumarin derivatives having a 1,4-diethyl-1,2,3,4-tetrahydroquinoxaline framework exhibited brilliant fluorescence. The novel chalcones absorbed in the range of 458-523 nm in various solvents. The wavelength of maximum absorption of these chalcones was found to be significantly longer than their simple acyl derivative known in the literature. The dyes displayed longer wavelength of absorption in the high polarity solvents compared to non-polar solvents. Thermogravimetric analysis of the chalcones revealed that the chalcones possess good thermal stability.  相似文献   

18.
The stable free radical polymerization (SFRP) process based on (1,3‐diphenyl‐1,4‐dihydro‐1,2,4‐benzotriazin‐4‐yl), the so‐called ‘Blatter radical’, and several C‐7 substituted derivatives is introduced for the first time for the polymerization of styrene. Polystyrenes characterized by polydispersity indices in the 1.05 ? 1.27 range were obtained in the presence of the Blatter radical and its derivatives containing CF3, Ph, Fur‐2‐yl and 4‐PhC6H4 substituents, while polymerization proceeded either in a non‐controlled manner or in very low polymerization yields in the presence of derivatives containing halogen (Cl, Br, I) substituents. This preliminary investigation, demonstrating the potential use of the Blatter radical and its derivatives in mediated SFRP, creates new opportunities to design and develop radicals to optimize performance in such polymerization processes. © 2013 Society of Chemical Industry  相似文献   

19.
Six soluble derivatives of 3,6-diphenyl-2,5-dihydro-pyrrolo[3,4-c]pyrrole-1,4-dione N-alkylated on pyrrolinone ring with polar substituents in para positions of pendant phenyl rings were synthesized; five of them are reported for the first time. Absorption and fluorescence spectra were studied in solvents of different polarity. The compounds show small solvatochromism of absorption and a moderate positive solvatochromism of fluorescence, especially when substituted by strong electron-donating piperidino substituent. A significant decrease of fluorescence quantum yields and its biexponential decay for dipolar derivatives in polar solvents was tentatively ascribed to the formation of twisted intramolecular charge transfer (TICT) excited state. All six compounds show fluorescence in polycrystalline solid-state with the maxima covering a range over 200 nm in visible and near infrared region.  相似文献   

20.
《Dyes and Pigments》2012,92(3):269-278
Six soluble derivatives of 3,6-diphenyl-2,5-dihydro-pyrrolo[3,4-c]pyrrole-1,4-dione N-alkylated on pyrrolinone ring with polar substituents in para positions of pendant phenyl rings were synthesized; five of them are reported for the first time. Absorption and fluorescence spectra were studied in solvents of different polarity. The compounds show small solvatochromism of absorption and a moderate positive solvatochromism of fluorescence, especially when substituted by strong electron-donating piperidino substituent. A significant decrease of fluorescence quantum yields and its biexponential decay for dipolar derivatives in polar solvents was tentatively ascribed to the formation of twisted intramolecular charge transfer (TICT) excited state. All six compounds show fluorescence in polycrystalline solid-state with the maxima covering a range over 200 nm in visible and near infrared region.  相似文献   

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