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Synthesis and Crystal Structure of Methyl 2-(Diphenylamino)-4-phenyl-1,3-thiazole-5-carboxylate
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作者 Ali Souldozi Seyed Hamid Reza Shojaei +2 位作者 Ali Ramazani Katarzyna lepokura Tadeusz Lis 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第1期82-88,共7页
The title compound, methyl 2-(diphenylamino)-4-phenyl-1,3-thiazole-5-carboxylate, was synthesized and studied by single-crystal X-ray diffraction method. The structure of the product was confirmed by IR, 1H- and 13C... The title compound, methyl 2-(diphenylamino)-4-phenyl-1,3-thiazole-5-carboxylate, was synthesized and studied by single-crystal X-ray diffraction method. The structure of the product was confirmed by IR, 1H- and 13C-NMR spectroscopy and elemental analysis. These experimental studies were supported by quantum mechanical calculations. The structure was solved in monoclinic, space group P21/c with a = 9.573(3), b = 19.533(7), c = 9.876(3), β = 92.35(4)°, V = 1845.2(10)3, T = 85(2) K, Z = 4, R = 0.040 and wR = 0.089 for 6424 observed reflections with I2σ(I). 展开更多
关键词 single-crystal X-ray structure multi-component reaction methyl 2-(diphenylamino)-4-phenyl-1 3-thiazole-5-carboxylate benzoyl isothiocyanate DIPHENYLAMINE dimethyl acetylenedicarboxylate
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−675 4G/5G and −844 G/A of Plasminogne Activator Inhibitor-1 (Pai-1) Gene Polymorphisms and Type 2 DiabetesMellitus in Tunisia: Case-Control Study
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作者 Mohamed Moustapha Molka Chadhli-Chaieb +1 位作者 Touhami Mahjoub Larbi Chaieb 《Open Journal of Endocrine and Metabolic Diseases》 2019年第7期75-83,共9页
Background: The plasminogen activator inhibitor-1 (PAI-1) is a puissant antifibrinolytic factor;plasma PAI-1 level is high in type 2 diabetes. 4G/5G polymorphism of PAI-1 gene is a major genetic determinant of plasma ... Background: The plasminogen activator inhibitor-1 (PAI-1) is a puissant antifibrinolytic factor;plasma PAI-1 level is high in type 2 diabetes. 4G/5G polymorphism of PAI-1 gene is a major genetic determinant of plasma PAI-1 levels, with 4G carriers having high PAI-1 level than 5G, theses pose the question about relation T2 patients and those polymorphisms. The aim of this study was to determine the relationship between the polymorphisms &minus;675 4G/5G and &minus;844 G/A of PAI-1 gene and type 2 diabetes mellitus. Methods: A case control study of 491 diabetic and 400 healthy controls. Genotyping of the polymorphism &minus;675 4G/5G was done by PCR-ASA (polymerase chain reaction, allele specific amplification), and the polymorphism &minus;844 G/A was done with PCR-RFLP (restriction fragment length polymorphism), the allelic frequency is calculated with hardy-Weinberg law, the statistic analysis was done by SPSS version 10. Results: Higher frequencies of The genotypes 4G/4G (p = 0.01) and 4G/5G of polymorphism &minus;675 4G/5G were seen in diabetic (p = 0.05) and higher frequencies of 5G/5G was seen in controls (p &minus;844 G/A was seen in diabetics and G/G was seen in controls (p = 0.01). Conclusion: Our study found association between 4G allele of &minus;675 4G/5G and A allele of &minus;844 G/A of PAI-1 gene and having type 2 diabetes mellitus in Tunisian population. 展开更多
关键词 Plasminogéne Activator Inhbitor-1 (PAI-1) ?675 4G/5G Polymorphism ?844 G/A Polymorphism Type 2 Diabetes Mellitus
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The Frequency of rs1799889 in Plasminogen Activator Inhibitor Type-1 Gene in Sudanese Type 2 Diabetic Patients, Gezira State, Sudan, 2020-2021
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作者 Rowida Eljack Ibrahim Sanaa Elfatih Hussein Ibrahim +4 位作者 Khalid Abdelsamea Mohamedahmed Abdarahim Ali Babikir Haj Alzebar Rania Ali Abdella Mohamed Adil Mergani Babiker Bakri Yousif Mohamed Nour 《Open Journal of Applied Sciences》 2022年第2期165-174,共10页
Background and Objectives: The cornerstone of the regulation fibrinolytic system is plasminogen activator inhibitor type-1. The 4G/5G polymorphism in the PAI-1 gene is a key genetic predictor of increased plasma level... Background and Objectives: The cornerstone of the regulation fibrinolytic system is plasminogen activator inhibitor type-1. The 4G/5G polymorphism in the PAI-1 gene is a key genetic predictor of increased plasma levels which is the most polymorphism associated with cardiovascular complications. The 4G carriers have six times higher PAI-1 levels than 5G carriers leading to an increase in the level of plasma inhibitor by about 25% more than 5G allele (wide type). Type 2 diabetes presents symptoms of hypercoagulability and hypofibrinolytic system that lead to contribute in the atherothrombosis and then the myocardial infarction (MI). These findings supported the hypothesis that there is a link between diabetes patients and this SNP. There is no data about the prevalence of this allele in Sudanese diabetic patients with type 2 and the allele differs in prevalence according to ethnicity, for these reasons, the aim of this study was to determine the allele and genotype frequency of the rs1799889 among Sudanese T2DM patients. Methods: A case-control study was conducted using 70 diagnosed diabetes type 2 patients and 50 healthy individuals as the control group. AS-PCR technique was used to genotype the rs1799889, and the allelic frequency was calculated according to Hardy-Weinberg equilibrium. Allelic frequencies were assessed using gene counting (SNP-STAT software V. Release 3.13), and genotypes were scored. Results: The result showed that 4G allele frequency was 28% among Sudanese diabetic patients without statistical difference when compared with control group (P-value = 0.998) but, high when compared with other studies in African population 13% and very low when compared with white and Indian populations studies. Conclusion: By this study, the allele frequency was higher in Sudanese diabetic patients with type 2, and also we need another study to evaluate the effect of this polymorphism in thrombophilic complications in Sudanese diabetic patients with type 2. 展开更多
关键词 4G/5G Polymorphism Diabetic Mellitus Type 2 and PAI-1 Gene
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Formation of Hybrid Ring Structure of Cyanurate/Isocyanurate in the Reaction be-tween 2,4,6-Tris(4-Phenyl-Phenoxy)-1, 3,5-Triazine and Phenyl Glycidyl Ether
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作者 Daisuke Ohno Kazuya Zenyoji +2 位作者 Youji Kurihara Kazuyoshi Ueda Hitoshi Habuka 《International Journal of Organic Chemistry》 CAS 2016年第2期117-125,共9页
Reaction products of 2,4,6-tris(4-phenyl-phenoxy)-1,3,5-triazine derived from 4-phenylphenol cyanate ester and phenyl glycidyl ether were analyzed. In addition to an isocyanurate compound and an oxazolidone compound w... Reaction products of 2,4,6-tris(4-phenyl-phenoxy)-1,3,5-triazine derived from 4-phenylphenol cyanate ester and phenyl glycidyl ether were analyzed. In addition to an isocyanurate compound and an oxazolidone compound which were well known as reaction products of cyanate esters and epoxy resins, compounds with hybrid ring structure of cyanurate/isocyanurate were determined. Gibbs free energies of the compound having hybrid ring structure of cyanurate/isocyanurate with two isocyanurate moiety were found to be lower than that of the compound with cyanurate ring structure through calculations. Calculation data supported the existence of hybrid ring structure of cy-anurate/isocyanurate. It was revealed that isomerization from cyanurate to isocyanurate occurs via hybrid ring structure of cyanurate/isocyanurate in the reaction of aryl cyanurate and epoxy. 展开更多
关键词 Reaction products of 2 4 6-tris(4-phenyl-phenoxy)-1 3 5-triazine derived from 4-phenylphenol cya-nate ester and phenyl glycidyl ether were analyzed. In addition to an isocyanurate compound and an oxazolidone compound which were well known as reaction products of cyanate esters and epoxy resins compounds with hybrid ring structure of cyanurate/isocyanurate were determined. Gibbs free energies of the compound having hybrid ring structure of cyanurate/isocyanurate with two isocyanurate moiety were found to be lower than that of the compound with cyanurate ring struc-ture through calculations. Calculation data supported the existence of hybrid ring structure of cy-anurate/isocyanurate. It was revealed that isomerization from cyanurate to isocyanurate occurs via hybrid ring structure of cyanurate/isocyanurate in the reaction of aryl cyanurate and epoxy.
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Synthesis, Crystal Structure and Antiproliferative Activity of 2-(((5-(((5,7-Dimethyl-[1,2,4]triazolo-[1,5-a]pyrimidin-2-yl)thio)methyl)-4-phenyl-4H-1,2,4-triazol-3-yl)thio)methyl)-4Hchromen-4-one Methanol Solvate
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作者 孙海燕 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第10期1467-1471,共5页
The novel crystal of the title compound 2-(((5-(((5,7-dimethyl-[1,2,4]triazolo-[1, 5-a]-pyrimidin-2-yl)thio)methyl)-4-phenyl-4H-1,2,4-triazol-3-yl)thio)methyl)-4H-chromen-4-one methanol solvate(C27H25N7O3... The novel crystal of the title compound 2-(((5-(((5,7-dimethyl-[1,2,4]triazolo-[1, 5-a]-pyrimidin-2-yl)thio)methyl)-4-phenyl-4H-1,2,4-triazol-3-yl)thio)methyl)-4H-chromen-4-one methanol solvate(C27H25N7O3S2, Mr = 559.66) has been prepared and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to the monocline system, space group P21/c with a = 11.9879(9), b = 14.0743(10), c = 15.9706(11)A, β = 98.509(2)°, V = 2664.9(3)A3, Z = 4, Dc = 1.395 g/cm^3, F(000) = 1168, μ = 0.116 mm-1, MoKa radiation(λ = 0.71073), R = 0.0652, and wR = 0.1425 for 5220 observed reflections with I 〉 2σ(I). X-ray diffraction analyses reveal that the molecule adopts a C-shape. The planes of the benzopyrone and triazolopyrimidine were nearly parallel to each other, with a dihedral angle of 1.21(3)°. Intramolecular and intermolecular hydrogen bonds together with π-π interations are found to exist in the structure. The results of MTT assay indicate that the title compound displays excellent antiproliferative activity against two human cancer cell lines. 展开更多
关键词 flavonoid 1 2 4-triazolo[1 5-a]pyrimidine single-crystal X-ray diffraction crystal structure SYNTHESIS antiproliferative activity
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Synthesis, Characterization, Spectroscopic Properties of 2-(4-Dimethylaminophenyl)-5-fluoro-6-(morpholin-4-yl)-1H-benzimidazole and its Interaction with Calf Thymus DNA
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作者 LingTianTANG YiWANG XinQiLIU ShaoWenHU TaiWeiCHU XiangYunWANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第3期345-348,共4页
Dimethylaminophenyl)-5-fluoro-6-(morpholin-4-yl)-1H-benzimidazole(1) has been synthesized and characterized by H-NMR, MS and elemental analysis. UV-Vis spectra of the 1 aqueous solutions at different pH values reveal ... Dimethylaminophenyl)-5-fluoro-6-(morpholin-4-yl)-1H-benzimidazole(1) has been synthesized and characterized by H-NMR, MS and elemental analysis. UV-Vis spectra of the 1 aqueous solutions at different pH values reveal that compound 1 can combine three protons. Its three protonation constants are determined by spectrophotometry and calculated by non-linear least squares. The results of steady-state fluorescence measurements indicate that a special interaction occurs between compound 1 and calf thymus DNA, of which the binding constant, Kb, is (2.30 ± 0.10)×l04 L/mol. Compound 1 in the concentration range of 10-8 to 1.2×10-6 mol/L could be used for quantitative determination of DNA. 展开更多
关键词 2-(4-Dimethylaminophenyl)-5-fluoro-6-(morpholin-4-yl)-1H-benzimidazole calf thymus DNA.
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The Synthesis of 2,4,6-Triisopropyl-1, 3,5-trioxane Catalyzed by Ionic Liquids 被引量:2
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作者 JianGuoYANG XinYuYU HaiHongWU ZhiLinCHENG YueMingLIU MingYuanHE 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第3期299-302,共4页
The synthesis of 2, 4, 6-triisopropyl-1, 3, 5-trioxane with high yield and desirable selec- tivity from solvent-free cyclotrimerization of isobutyraldehyde catalyzed by ionic liquids was reported in this work.
关键词 ISOBUTYRALDEHYDE cyclotrimerization 2 4 6-triisopropyl-1 3 5-trioxane ionic liquids.
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Synthesis of 2-(N-formyl)-5-aryl/aryloxymethyl-1,3,4-thiadiazoles with potential bioactivity in PEG-400 被引量:1
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作者 Wang, Xi Cun Ding, Xiao Mei +2 位作者 Wang, Sheng Qing Chen, Xue Fei Quan, Zheng Jun 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期301-304,共4页
An environmental benign procedure for synthesis of 2-(N-formyl)-5-aryl/aryloxymethyl-1,3,4-thiadiazoles has been developed by reaction of 2-amino-5-aryl/aryloxymethyl-1,3,4-thiadiazoles with formic acid in PEG-400.The... An environmental benign procedure for synthesis of 2-(N-formyl)-5-aryl/aryloxymethyl-1,3,4-thiadiazoles has been developed by reaction of 2-amino-5-aryl/aryloxymethyl-1,3,4-thiadiazoles with formic acid in PEG-400.The key advantages of this protocol are the shorter reaction time,higher yields,lower cost,simple workup,and environment-friendly compared to conventional organic solvent reaction.The present method does not involve any hazardous organic solvent or catalyst. 展开更多
关键词 2-(N-Formyl)-5-aryl/aryloxymethyl-1 3 4-thiadiazoles 2-Amino-5-aryl/aryloxymethyl-1 PEG-400 Synthesis
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Effect of 2-butyne-1, 4-diol on silver electrodeposition from 5, 5-dimethyl hydantoin solutions 被引量:1
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作者 LU Junfeng AN Maozhong ZHENG Huanyu 《Rare Metals》 SCIE EI CAS CSCD 2006年第z2期255-259,共5页
The effect of 2-butyne-1, 4-diol on silver electrodeposition process from 5, 5-dimethyl hydantoin solutions was investigated by means of cyclic voltammetric measurement, scanning electron microscopy (SEM) and X-ray di... The effect of 2-butyne-1, 4-diol on silver electrodeposition process from 5, 5-dimethyl hydantoin solutions was investigated by means of cyclic voltammetric measurement, scanning electron microscopy (SEM) and X-ray diffraction (XRD). Cyclic voltammetric studies indicate that the reduction process of silver electrodeposition is influenced by adding 2-butyne-1, 4-diol. Owing to its adsorption on the electrode surface, 2-butyne-1, 4-diol moderately hinders the mass transfer of the silver complexed ions from the bulk solution to the outer limit of the electrode double layer and affects the electrocrystallization step. Scanning electron microscopy analysis reveals that the presence of 2-butyne-1, 4-diol in the electrolyte is beneficial and the silver deposits obtained are smoother, more compact and more leveled. X-ray diffraction analysis of the silver deposits obtained at 0.5 g·L-1 2-butyne-1, 4-diol indicated that the (110) plane is the most preferred plane and is not affected by the presence of 2-butyne-1, 4-diol in the electrolyte. 展开更多
关键词 silver electrodeposition 5 5-dimethyl hydantoin solutions 2-butyne-1 4-diol electrocrystallization
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Potassium dihydrogen phosphate catalyzed one-pot synthesis of 2,4,5-triaryl-1H-imidazoles 被引量:2
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作者 Ratnadeep S.Joshi Priyanka G.Mandhane +2 位作者 Mohammad U.Shaikh Rajesh P.Kale Charansingh H.Gill 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第4期429-432,共4页
A simple and efficient method has been developed;benzil/benzoin undergoes smooth condensation with various substituted aldehyde and ammonium acetate in the presence of potassium dihydrogen phosphate(KH;PO;) under mi... A simple and efficient method has been developed;benzil/benzoin undergoes smooth condensation with various substituted aldehyde and ammonium acetate in the presence of potassium dihydrogen phosphate(KH;PO;) under mild reaction conditions to afford the corresponding trisubstituted imidazole in excellent yields.The method for synthesis of product,the reaction mixture was reflux in ethanol for 40-90 min.The present method is simple,efficient,and cost-effective. 展开更多
关键词 Potassium dihydrogen phosphate(KH_2PO_4) 2 4 5-Triaryl-1H-imidazole Benzil Benzoin Aldehyde Ammonium acetate
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Crystal and Molecular Structure of 2-(2, 6-Dinitro-4-Trifluoromethyl) phenylthio-5, 7-Dimethyl-1,2,4-Triazolo [1, 5-a] Pyrimidine 被引量:1
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作者 YANG Guang-Fu LU Rong-Jian YANG Hua-Zheng(Institute of Elemento-Organic Chemistry, Nankai University, Tianjin, 300071)WANG Hong-Gen(Central Laboratory of Nankai Univiersity, Tianjin, 300071) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1997年第4期298-301,共4页
The crystal structure of the title compound has been determined bysingle crystal X-ray diffraction analysis. C14H9F3N6O4S, Mr = 414. 32, monoclinic,space group P21/n, a=8. 287(3), b= 24. 972(4), c= 8. 617(3)A, β= 108... The crystal structure of the title compound has been determined bysingle crystal X-ray diffraction analysis. C14H9F3N6O4S, Mr = 414. 32, monoclinic,space group P21/n, a=8. 287(3), b= 24. 972(4), c= 8. 617(3)A, β= 108. 36(3)°,V= 1693(2) A3, Z=4, Dx=1. 626 g. cm-3, μ=0. 2481 mm-1; F(000) =840, finalR = 0. 057 and Rw= 0. 057 for 1169 observed reflections [I≥3σ(I)]. The results showthat all ring atoms in the triazolopyrimidinyl moiety were coplanar with strong tensileforce, which might be an important active site. 展开更多
关键词 crystal structure 1 2 4-triazolo[1 5-a]pyrimidine compound biological activity
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A Y(Ⅲ)-organic Coordination Polymer Constructed from 2-(Pyridine-4-yl)-1H-imidazole-4,5-dicarboxylate and Oxalate Ligands: Structure and Luminescent Property
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作者 郭向广 吴小园 +4 位作者 张其凯 杨文斌 林琅 余荣民 卢灿忠 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第1期57-62,共6页
A novel compound, {[Y(HPIDC)(OX)1/2(H2O)]·2H2O}n (1, H3PIDC = 2-(pyridin-4- yl)-1H-imidazole-4,5-dicarboxylic acid, H2OX = oxalic acid), has been synthesized under hydrothermal conditions and characteri... A novel compound, {[Y(HPIDC)(OX)1/2(H2O)]·2H2O}n (1, H3PIDC = 2-(pyridin-4- yl)-1H-imidazole-4,5-dicarboxylic acid, H2OX = oxalic acid), has been synthesized under hydrothermal conditions and characterized by thermal analysis (TGA), powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction. Complex 1 crystallizes in monoclinic space group P21/c with a = 8.342(8), b = 14.61(1), c = 11.487(1), β = 90.78(9)°, V = 1400.4(2)3, Z = 4, C11H11N3O9Y, Mr = 418.14, Dc = 1.983 g/cm3, F(000) = 836, Rint = 0.0509, T = 293(2) K, μ = 4.240 mm-1, the final R = 0.0477 and wR = 0.1125 for 2770 observed reflections with I 2σ(I). Compound 1 exhibits a 3D framework and generates the 1D open channels filled with free water molecules. The structure of 1 can be rationalized as a diamondoid network when the atom yttrium is regarded as a 4-connected node linking four surrounding yttrium atoms. The luminescent property of compound 1 is also investigated. 展开更多
关键词 Y(Ⅲ) coordination polymer hydrothermal synthesis 2-(pyridin-4-yl)-1H-imidazole-4 5-dicarboxylic acid diamondiod network luminescence
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The Synthesis of Novel Annelated 2-Oxopiperazines by the Interaction Methyl (3-Oxopiperazin-2-Ylidene) Acetate with an N-Arylmaleimides
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作者 Svetlana Mikhajlovna Medvedevat Khidmet Safarovich Shikhaliev 《材料科学与工程(中英文A版)》 2015年第7期310-313,共4页
关键词 马来酰亚胺 乙酸甲酯 芳基 偶极环加成反应 合成 交互 相互作用 醋酸
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The First Two-dimensional Supramolecular Network Constructed by Na(Ⅰ) with 2-Methylimidazole-4,5-dicarboxylate Building Blocks 被引量:2
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作者 涂勇刚 熊志强 +3 位作者 宋秀英 聂旭亮 温世和 刘光斌 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第12期1770-1774,共5页
The title complex [Na(H2MIA-)(H2O)](1,H3MIA = 2-methyl-1H-imidazole-4,5-dicarboxylic acid) has been synthesized by hydrothermal synthesis and structurally characterized by X-ray crystallography.Compound 1 crysta... The title complex [Na(H2MIA-)(H2O)](1,H3MIA = 2-methyl-1H-imidazole-4,5-dicarboxylic acid) has been synthesized by hydrothermal synthesis and structurally characterized by X-ray crystallography.Compound 1 crystallizes in orthorhombic,space group ibam with a = 14.4737(19),b = 17.553(2),c = 6.5285(9),V = 1658.6(4) 3,C6H7N2NaO5,Mr = 210.12,Z = 8,Dc = 1.675 g/cm3,F(000) = 864,μ = 0.188 mm-1,λ(MoKα) = 0.071073 ,R = 0.0383 and wR = 0.0987 for 1046 observed reflections(I 2σ(I)).In the structure of 1,each coordination water coordinates with two Na(I) ions at the same time and links the neighboring Na(I) ions to form a one-dimensional Na(I)-water chain.Each H2MIA-ligand links the neighboring Na(I) of Na(I)-water chain to form a novel two-dimensional supramolecular network.The 2-D network is stabilized by O-H…N hydrogen bonds and π-π interaction.The 2D network is further linked via O-H…O hydrogen bonds to yield a three-dimensional framework. 展开更多
关键词 NA 2-methyl-1H-imidazole-4 5-dicarboxylic acid hydrothermal synthesis crystal structure
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Effect of Temperature on the Reaction of 2-(N-acetylamine)-3-(3,5-di-<i>tert</i>-butyl-4-hydroxyphenyl)-propionic Acid with Oxygen in an Alkaline Condition
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作者 A. A. Volodkin G. E. Zaikov +3 位作者 L. N. Kurkovskaja S. M. Lomakin I. M. Levina E. V. Koverzanova 《Advances in Chemical Engineering and Science》 2015年第3期262-269,共8页
Results of oxidation 2-(N-acetylamine)-3-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid oxygen depend on temperature. At 55℃?- 60℃, 2,4-di-tert-butylbicyclo(4,3,1)deca-4,6-dien-8-(N-acetylamine)-3,9-dion-1-oxa i... Results of oxidation 2-(N-acetylamine)-3-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid oxygen depend on temperature. At 55℃?- 60℃, 2,4-di-tert-butylbicyclo(4,3,1)deca-4,6-dien-8-(N-acetylamine)-3,9-dion-1-oxa is formed. The constitution is based on dates of spectrums 1Н and 13С NMR. At 95℃?- 97℃, mixtures of 2,4-di-tert-butylbicyclo(4,3,1)deca-4,6-dien-8-(N-acetylamine)-3,9-dion-1-oxa and of 6,8-di-tert-butyl-3-(N-acetylamine)spiro(4,5)deca-1-oxa-5,8-dien-2,7-dione are produced. Structures are calculated by the method of Hartrii-Foka. Values of enthalpies and of entropies allow to assume dynamic isomerism. 展开更多
关键词 2-(N-acetylamine)-3-(3 5-di-tert-butyl-4-hydroxyphenyl)-propionic Acid 6 8-di-tert-butyl-3-(N-acetylamine)spiro(4 5)deca-1-oxa-5 8-dien-2 7-dione Oxidation by OXYGEN 2 4-Di-tert-butylbicyclo(4 3 1)deca-4 6-dien-8-(N-acetylamine)-3 9-dion-1-oxa NMR-Spectroscopy
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5-[4-硝基呋咱基]-5H-[1,2,3]三唑并[4,5-c][1,2,5]呋咱内盐(NOTO)合成与表征 被引量:2
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作者 张叶高 王伯周 +2 位作者 刘愆 周彦水 王锡杰 《含能材料》 EI CAS CSCD 北大核心 2010年第4期383-386,共4页
以二氨基呋咱(DAF)为起始原料,经Caro′sacid氧化、锌粉还原、环化和Caro′sacid二次氧化四步反应得到5-[4-硝基呋咱基]-5H-[1,2,3]三唑并[4,5-c][1,2,5]呋咱(NOTO)内盐,总收率为17.5%(以DAF计),并利用元素分析、核磁共振、红外光谱等... 以二氨基呋咱(DAF)为起始原料,经Caro′sacid氧化、锌粉还原、环化和Caro′sacid二次氧化四步反应得到5-[4-硝基呋咱基]-5H-[1,2,3]三唑并[4,5-c][1,2,5]呋咱(NOTO)内盐,总收率为17.5%(以DAF计),并利用元素分析、核磁共振、红外光谱等进行了结构表征;首次采用Zn粉还原二氨基偶氮氧化呋咱(DAAzF)合成关键中间体二氨基偶氮呋咱(DAAF),收率92%;探讨了5-[4-硝基呋咱基]-5H-[1,2,3]三唑并[4,5-c][1,2,5]呋咱(AMOTO)环化反应机理,确定DAAF和二乙酰氧基碘苯(IBD)的最佳料比为11,重结晶后AMOTO纯度达到99.4%。 展开更多
关键词 有机化学 5-[4-硝基呋咱基]-5H-[1 2 3]三唑并[4 5-c][1 2 5]呋咱(noTO)内盐 合成 表征
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2,3-二氯-5,6-二氰基-1,4-苯醌/NaNO2催化9,10-二氢蒽氧化脱氢 被引量:4
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作者 张伟 马红 +2 位作者 周利鹏 苗虹 徐杰 《催化学报》 SCIE EI CAS CSCD 北大核心 2009年第2期86-88,共3页
设计了一种由2,3-二氯-5,6-二氰基-1,4-苯醌(DDQ)和NaNO2组成的复合催化剂,该催化剂在9,10-二氢蒽氧化脱氢生成蒽的反应中表现出很高的催化活性和选择性.在120℃和1.3MPaO2下反应8h,9,10-二氢蒽转化率达到99%以上,蒽的选择性为99%.采用... 设计了一种由2,3-二氯-5,6-二氰基-1,4-苯醌(DDQ)和NaNO2组成的复合催化剂,该催化剂在9,10-二氢蒽氧化脱氢生成蒽的反应中表现出很高的催化活性和选择性.在120℃和1.3MPaO2下反应8h,9,10-二氢蒽转化率达到99%以上,蒽的选择性为99%.采用红外光谱和核磁共振方法对催化氧化脱氢的反应历程进行了研究.结果表明,9,10-二氢蒽氧气氧化脱氢生成蒽的反应是通过DDQ/DDQH2和NO2/NO两个氧化还原对的电子传递来推动的,以DDQ/NaNO2为催化剂可以有效催化9,10-二氢蒽氧化脱氢生成蒽. 展开更多
关键词 2 3-二氯-5 6-二氰基-1 4-苯醌 亚硝酸钠 9 10-二氢蒽 氧化脱氢
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The Isogene 1-Deoxy-D-Xylulose 5-Phosphate Synthase 2 Controls Isoprenoid Profiles, Precursor Pathway Allocation, and Density of Tomato Trichomes 被引量:13
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作者 Heike Paetzold Stefan Garms +7 位作者 Stefan Bartram Jenny Wieczorek Eva-Maria Uros-Gracia Manuel Rodriguez-Concepcion Wilhelm Boland Dieter Strack Bettina Hause Michael H. Walter 《Molecular Plant》 SCIE CAS CSCD 2010年第5期904-916,共13页
Plant isoprenoids are formed from precursors synthesized by the mevalonate (MVA) pathway in the cytosol or by the methyl-D-erythritol 4-phosphate (MEP) pathway in plastids. Although some exchange of precursors occ... Plant isoprenoids are formed from precursors synthesized by the mevalonate (MVA) pathway in the cytosol or by the methyl-D-erythritol 4-phosphate (MEP) pathway in plastids. Although some exchange of precursors occurs, cytosolic sesquiterpenes are assumed to derive mainly from MVA, while plastidial monoterpenes are produced preferentially from MEP precursors. Additional complexity arises in the first step of the MEP pathway, which is typically catalyzed by two divergent 1-deoxy-D-xylulose 5-phosphate synthase isoforms (DXS1, DXS2). In tomato (Solanum lycopersicum), the SIDXS1 gene is ubiquitously expressed with highest levels during fruit ripening, whereas SIDXS2 transcripts are abundant in only few tissues, including young leaves, petals, and isolated trichomes. Specific down-regulation of SIDXS2 expression was performed by RNA interference in transgenic plants to investigate feedback mechanisms. SIDXS2 down-regulation led to a decrease in the monoterpene β-phellandrene and an increase in two sesquiterpenes in trichomes. Moreover, incorporation of MVA-derived precursors into residual monoterpenes and into sesquiterpenes was elevated as determined by comparison of ^13C to ^12C natural isotope ratios. A compensatory up-regulation of SIDXS1 was not observed. Down-regulated lines also exhibited increased trichome density and showed less damage by leaf-feeding Spodoptera littoralis caterpillars. The results reveal novel, non-redundant roles of DXS2 in modulating isoprenoid metabolism and a pronounced plasticity in isoprenoid precursor allocation. 展开更多
关键词 Isoprenoid biosynthesis methyI-D-erythritol 4-phosphate (MEP) pathway 1-deoxy-D-xylulose 5-phosphate synthase 2 (DXS2 RNA interference (RNAi) TRICHOMES cross-talk feedback regulation GC-C-IRMS.
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缩合试剂2-氯-4,6-二甲氧基-1,3,5-三嗪的合成与应用
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作者 胡居吾 卢曦 +1 位作者 张鹏 邓方坤 《当代化工研究》 CAS 2024年第20期179-181,共3页
2-氯-4,6-二甲氧基-1,3,5-三嗪(CDMT)是商品化的常用于羧酸的活化和酰胺合成的缩合试剂。CDMT制备简单,成本低廉,活性高,适合工业化生产使用。CDMT与羧酸在有机碱N-甲基吗啉(NMM)作用下生成活性脂。本文对2-氯-4,6-二甲氧基-1,3,5-三嗪... 2-氯-4,6-二甲氧基-1,3,5-三嗪(CDMT)是商品化的常用于羧酸的活化和酰胺合成的缩合试剂。CDMT制备简单,成本低廉,活性高,适合工业化生产使用。CDMT与羧酸在有机碱N-甲基吗啉(NMM)作用下生成活性脂。本文对2-氯-4,6-二甲氧基-1,3,5-三嗪的合成方法,和其在酰胺,肽,脂,酸酐,醛,酮,芳香酮,炔酮,芳基偶联物,3,5-二取代1,2,4-恶二唑合成中的应用进行了综述。 展开更多
关键词 2-氯-4 6-二甲氧基-1 3 5-三嗪(CDMT) 缩合试剂
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苯并[1,2-b:4,5-b′]二噻吩-thieno[3,4-b]thiadiazole导电性的理论研究
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作者 邓理丹 苏宇 +1 位作者 申明金 曹洪斌 《河南科学》 2014年第3期343-346,共4页
采用密度泛函理论,在B3LYP/6-31G(d)水平下,对苯并[1,2-b:4,5-b′]二噻吩(BDT)-thieno[3,4-b]thiadiazole(TD)的低聚物和聚合物进行了理论计算.其中,BDT为电子供体,TD为电子受体,以1∶2的方式结合形成化合物,并计算了二面角、分子内的... 采用密度泛函理论,在B3LYP/6-31G(d)水平下,对苯并[1,2-b:4,5-b′]二噻吩(BDT)-thieno[3,4-b]thiadiazole(TD)的低聚物和聚合物进行了理论计算.其中,BDT为电子供体,TD为电子受体,以1∶2的方式结合形成化合物,并计算了二面角、分子内的电荷传输、桥键键长和中心键电荷密度.结果显示:随着聚合链增长,共轭程度增加.NICSs值显示:中心环比边环的共轭程度更大.聚合物的能带结构表明:该聚合物的带隙比较低(0.87 eV),故其可以作为潜在的导电材料. 展开更多
关键词 密度泛函理论 苯并[1 2-b 4 5-b’]二噻吩 共轭聚合物 导电材料
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