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1.
Thirteen compounds with ester and amide linkages were synthesized and their mesogenic properties evaluated. Methyl to n-propyl derivatives exhibit nematic phases, n-butyl to n-decyl derivatives exhibit smectic and nematic mesophases, whereas n-dodecyl to n-octadecyl derivatives exhibit only smectic phases. All the smectic homologues exhibit smectic C phases. Middle members of the homologous series exhibit polymorphism of smectic mesophase. A plot of transition temperatures versus number of carbon atoms in the alkoxy chain reveals an odd-even effect for nematic-isotropic transition temperatures. Nematic-isotropic and smectic-cholesteric thermal stabilities of the prepared compounds (series I) are higher compared to those of previously reported compounds, series A, B and C. The results indicate that a simple reversal of a central linkage has a dramatic effect on the appearance of smectic mesophase in a homologous series. The structures of the synthesized compounds were characterized using elemental analysis, thin-layer chromatography and spectral data.  相似文献   

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孙勇  丁明武 《合成化学》2004,12(1):49-52,80
用烯基膦亚胺与4-甲苯基异氰酸酯、对甲硫苯酚的串联aza-Wittig反应合成了2-(4-甲硫基苯氧基)-3-(4-甲苯基)-4H-咪唑啉-4-酮衍生物.探讨了反应进行的条件和产物的波谱性质,提出了可能的环化反应机理.生成的环化产物均为新的化合物,其结构经元素分析、IR、1H NMR和MS确证.并探讨了所合成的新型杂环化合物的生物活性,结果表明部分化合物表现出良好的抑菌活性,其中3f的活性最好,在质量分数为5×10-5浓度时,对稻瘟菌和苹果轮纹菌的抑制率均达到100%.  相似文献   

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Synthesis was performed of 4-(4-ethoxycarbonylphenylamino)- and 4-(2-carboxyphenylamino)-2-methylquinolines by reaction of 2-methyl-4-chloroquinoline with anesthesin and anthranilic acid. In concentrated sulfuric acid 4-(2-carboxyphenylamino)-2-methylquinoline underwent cyclization into 6-hydroxy-7-methylquinolino[3,2-c]quinoline, and the alkaline hydrolysis of 4-(4-ethoxycarbonylphenyl-amino)quinoline afforded 2-methyl-4-(4-carboxyphenylamino)quinoline.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 5, 2005, pp. 786–787.Original Russian Text Copyright © 2005 by Avetisyan, Aleksanyan, Ambartsumyan.  相似文献   

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Reactions of 4-hydrazinobenzoic acid with 2-formyl- and 2-acetyldimedones were utilized to synthesize 6,6-dimethyl- and 3,6,6-trimethyl-1-(4-hydroxycarbonylphenyl)-4-oxo-4,5,6,7-tetrahydroindazoles corre-spondingly, and the reaction with 2-cyano-3-ethoxy-5,5-dimethylcyclohex-2-en-1-one gave 2-(4-hydroxy-carbonylphenyl)-3-amino-4-oxo-6,6-dimethyl-4,5,6,7-tetrahydroindazole. Riga Technical University, Riga LV-1658. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 516–519, April, 1997.  相似文献   

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陈贯虹  王加宁  孔学  刘可春 《应用化学》2011,28(12):1375-1378
研究了1-(4-氯苯胺基)-4-(4-吡啶甲基)-2,3-二氮杂萘琥珀酸盐的合成工艺,采用苯酞和吡啶甲醛为起始原料,经加成、重排、取代和成盐4步反应得到目标化合物。 中间体及目标化合物通过1H NMR、MS和HPLC进行了表征。 重结晶纯化后的目标化合物纯度为98.1%。 对荷瘤(人大肠癌HT 29细胞)裸鼠的抑癌活性测定表明,该化合物具有明显的抑制肿瘤生长作用。  相似文献   

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Some substituted 2-ethyl-3-(4-hydrazinocarbonylphenyl)-4-quinazolones and 2-ethyl-3-(4-hydrazinocarbonylmethylphenyl)-4-quinazolones were synthesized and characterized by their sharp melting points, elemental analyses and spectral data.  相似文献   

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The temperature dependences of the dielectric permittivity of 4-(2,3-epoxypropoxy)-4'-alkoxyazoxybenzenes (n = 1-10) and 4-propoxy-4'-alkoxyazoxybenzenes (n = 1-10) with mesomorphic properties were measured by dielectrometry. The introductrion of the terminal epoxy group increases the dielectric permittivity and its anisotropy. The dipole moments of molecules of 4-(2,3-epoxypropoxy)-4'-alkoxyazoxybenzenes (n = 1-10) and 4-propoxy-4'-alkoxyazoxybenzenes (n = 1-10) were determined by the second Debye method. The epoxy-substituted azoxybenzenes have higher dipole moments than their structural analogs.  相似文献   

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We investigated the electronic structure and chemical bonding of two bimetallic clusters NaGa4- and NaIn4-. Photoelectron spectra of the anions were obtained and compared with ab initio calculations. We found that the ground state of the two anions contains a square planar dianion interacting with a Na+ cation. The Ga4(2-) and In4(2-) dianions both possess two delocalized pi electrons and are considered to be aromatic, similar to that recently found in Al4(2-). Using calculations for a model compound, we showed that a recently synthesized Ga4-organometallic compound also contains an aromatic -Ga4(2-)- unit, analogous to the gaseous clusters.  相似文献   

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合成了聚马来酸6-(4-辛氧基偶氮苯氧基)-1-己酯(PMAN-OAB),并以其为质子给体,4-(4-庚氧基苯甲酰氧基)-苯乙烯基吡啶(7SZ)为质子受体,研究了两者复合前后的液晶行为,结果表明,PMAN-OAB在液晶态时是以羧酸二聚体形式存在的,其倾角为39.3°,7SZ含量在40%~90%范围内的复合物液晶范围比7SZ和PMAN-OAB的宽。  相似文献   

14.
咪唑啉酮;2-(4-甲硫基苯氧基)-4H-咪唑啉-4-酮衍生物的合成及生物活性  相似文献   

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1 INTRODUCTION The triazole derivatives were widely studied because they represent the largest group of modern fungicides and extensively used in both human and veterinary therapy and in agriculture[1~3]. For exam- ple, there are commercially available …  相似文献   

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Chemistry of Heterocyclic Compounds -  相似文献   

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Starting from readily available 2-substituted-4-formylthiazoles and selenazoles, a series of 4-(2-aryl-4-selenazolyl)-1,2,3-selenadiazoles I and 4-(2-substituted-4-thiazolyl)-1,2,3-selenadiazoles II were prepared. Pyrolysis of compound II afforded (2-substituted-4-thiazolyl) acetylenes VII. Addition of potassium hydroxide pellets to an alcoholic solution of II gave 2-substituted-1,4-diselenafulvenes VIII. Decomposition of compound II with base followed by the addition of carbon disulfide gave 5-substituted 2-thioxo-1,3-thiaselenoles XI.  相似文献   

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