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A novel synthesis of pyrazolo[3,4-b]pyridine derivatives through multi-component reaction in ionic liquid 被引量:3
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作者 Xin Ying Zhang Xiao Yan Li Xue Sen Fan Xia Wang Jian Ji Wang Gui Rong Qu 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第2期153-156,共4页
关键词 Pyrazolo[3 4-b]pyridine Multi-component reaction Ionic liquid
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Synthesis, Reactions and Characterization of 1,1’-(1,4-Phenylenebis(3-amino-6-methyl-1H-pyrazolo[3,4-b]pyridine-4,5-diyl))bis(ethan-1-one)
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作者 Ahmed A. M. Elreedy Hameed M. Alkubaisi Fawzy A. Attaby 《International Journal of Organic Chemistry》 CAS 2016年第1期65-76,共12页
Reaction of 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-thioxo-1,2-dihydropyridine-3-carbonitrile) (1) with methyl iodide afforded the 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-(methylthio)nicotinonitrile) (2). Th... Reaction of 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-thioxo-1,2-dihydropyridine-3-carbonitrile) (1) with methyl iodide afforded the 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-(methylthio)nicotinonitrile) (2). The reaction of 2 with hydrazine hydrate followed by diazotization reaction af-forded the 1,1’-(1,4-phenylenebis(3-amino-6-methyl-1H-pyrazolo[3,4-b]pyridine-4,5-diyl))bis(e-than-1-one) (3) and 1,1’-(1,4-phenylenebis(3-(chlorodiazenyl)-6-methyl-1H-pyrazolo[3,4-b]-pyridine-4,5-diyl))bis(ethan-1-one) (4) respectively. On the other hand, reaction of 4 with malononitrile, 2-cyanoethanethioamide, ethyl acetoacetate, acetyl acetone, ethyl benzoylacetate, diethylmalonate, ethyl cyanoacetate and phenacylbromide aiming to build up pyrazolotriazine or pyrazole ring on the ring system of 4. Structures of all newly synthesized heterocyclic compounds in the present study were confirmed by considering the data of IR, 1H NMR, mass spectra as well as that of elemental analyses. 展开更多
关键词 Bis-1 2-dihydropyridine-3-carbonitrile Bis-Nicotinonitrile 1 1’-(1 4-Phenyl-enebis(3-(chlorodiazenyl)-6-methyl-1H-pyrazolo[3 4-b]pyri-dine-4 5-diyl))bis(ethan-1-one) Bis-dihydropyrido[2’ 3’:3 4]pyrazolo[5 1-c][1 2 4]triazine-3-carboxylate Bis-1H-pyrazolo[3 4-b]pyridine
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Selective Synthesis of 1,2-Diarylpyrrolo[3,4-b]pyridine-5,7- diones via Cyclization Reaction of β-Enamino Imides with Cinnamaldehydes
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作者 Yanhong Jiang Chaoguo Yan 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2016年第12期1255-1262,共8页
The novel 1,2-diaryl substituted pyrrolo[3,4-b]pyridine-5,7-diones were selectively synthesized in high yields by the base catalyzed cyclization reaction of 3-arylamino-l-methyl-lH-pyrrole-2,5-diones with cinnamaldehy... The novel 1,2-diaryl substituted pyrrolo[3,4-b]pyridine-5,7-diones were selectively synthesized in high yields by the base catalyzed cyclization reaction of 3-arylamino-l-methyl-lH-pyrrole-2,5-diones with cinnamaldehyde and its derivatives in acetonitrile at room temperature. However, when piperidinium trifluoroacetate was employed as catalyst, the reaction afforded a mixture of 1,2-diaryl and 1,4-diaryl substituted pyrrolo[3,4-b]pyridine-5,7-diones in comparable yields. 展开更多
关键词 pyrrolo[3 4-b]pyridine 1 2-dihydropyridine 1 4-DIHYDROpyridine β-enamino amide CINNAMALDEHYDE
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New and Facile Synthesis of Substituted Pyrrole, Pyridine, Pyrazolo[4,3-b] Pyridine, Pyrano[3,2-c] Quinoline, Napthopyran, Naphthodipyran and Coumarin Derivatives
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作者 F. M. A. El-Taweel A. A. Elagamey 《International Journal of Organic Chemistry》 2013年第1期58-70,共13页
Several new pyrazolo[4,3-b] pyridines 7a, b were prepared by reacting arylidenemalononitriles 1a, c or 1i, j with 4-nitrosoantipyrine 4. Reacting 1a, b, d with 4-azidomethylcarbonylantipyrine 8 give 2-aminopyrrole 14.... Several new pyrazolo[4,3-b] pyridines 7a, b were prepared by reacting arylidenemalononitriles 1a, c or 1i, j with 4-nitrosoantipyrine 4. Reacting 1a, b, d with 4-azidomethylcarbonylantipyrine 8 give 2-aminopyrrole 14. Pyrano[3,2-c] quinolines 20a, b and 23 were obtained by reacting 4-hydroxyquinoline 15 with 1g, h, 2b respectively. Reaction of 1 with naphthalenediols 24, 27 and 29 yield naphthodipyrans 26a, b, 28a, b and 30a。 展开更多
关键词 PYRROLE pyridine Pyrazolo[4 3-b] pyridine Pyrano[3 2-c] QUINOLINE NAPHTHOPYRAN Naphthodipyrans and Coumarin
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Theoretical Study on the Reaction Mechanism of 2-Methoxybenzaldehyde,4-Bromo-indanone,Malononitrile and Ammonium Acetate One-pot to Form 6-(2-Methoxyphenyl)-2-amino-6-bromo-5H-indeno[1,2-b]pyridine-3-carbonitrile
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作者 张福兰 黄辉胜 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第10期1685-1696,共12页
The reaction mechanism of 2-methoxybenzaldehyde, 4-bromo-indanone, malononitrile and ammonium acetate one-pot to form 6-(2-methoxyphenyl)-2-amino-6-bromo-5 Hindeno[1,2-b]pyridine-3-carbonitrile was studied by densit... The reaction mechanism of 2-methoxybenzaldehyde, 4-bromo-indanone, malononitrile and ammonium acetate one-pot to form 6-(2-methoxyphenyl)-2-amino-6-bromo-5 Hindeno[1,2-b]pyridine-3-carbonitrile was studied by density functional theory. The geometries of the reactants, transition states, intermediates and products were optimized at the PW91/DNP level. Vibration analysis was carried out to confirm the transition state structure. Reaction pathways were investigated in this study. The result indicates that the reaction Re→ TSB1→IMB1→ TSB2→ IMB2→TSB3→IMB3→TSB4→IMB4→TSB5→IMB5→TSB6→IMB6→TSB7→IMB7→ TSB8→IMB8→TSB9→IMB9→P2 is the main pathway, the activation energy of which is the lowest. The dominant product predicted theoretically is in agreement with the experiment results. 展开更多
关键词 2-methoxybenzaldehyde 4-bromo-indanone 6-(2-methoxyphenyl)-2-amino-6-bromo-5H-indeno[1 2-b]pyridine-3-carbonitrile density functional reaction mechanism
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A New Diiminopyridyl Cobalt Complex [CoCl_2L](L=2,6-Bis(N,N'-bis(2,6-diisopropyl-4-(2,3-dimethyoxylbenzoylamide)phenylimino))pyridine)
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作者 龙泽荣 赵启龙 +2 位作者 李少光 夏娅娜 吴彪 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第6期869-874,共6页
The reaction of CoCl2·6H2O with 2,6-bis(N,N'-bis(2,6-diisopropyl-4-(2,3-dimethy-oxyl-benzoylamide)phenylimino))pyridine(L) afforded the complex [CoCl2L],which was fully characterized by elemental analysi... The reaction of CoCl2·6H2O with 2,6-bis(N,N'-bis(2,6-diisopropyl-4-(2,3-dimethy-oxyl-benzoylamide)phenylimino))pyridine(L) afforded the complex [CoCl2L],which was fully characterized by elemental analysis,UV-vis,IR spectroscopy,fluorescence,and X-ray diffraction analysis.The compound is of triclinic system,space group P1 with a = 13.058(3),b = 13.798(3),c = 16.695(3) ,α = 98.191(3),β = 102.792(3),γ = 101.820(3)°,V = 2815.0(9) 3,Z = 2,F(000) = 1122,μ = 0.45 mm-1,R = 0.061 and wR = 0.1349 for 9842 observed reflections(Ⅰ 〉 2σ(Ⅰ)).The Co(Ⅱ) center adopts a distorted square-pyramidal coordination geometry.The extended structure shows a one-dimensional zigzag double chain linked by hydrogen bonds and π-π stacking interactions. 展开更多
关键词 2 6-bis(N N'-bis(2 6-diisopropyl-4-(2 3-dimethyoxylbenzoylamide)phenylimino)) pyridine cobalt crystal structure fluorescence
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Crystal Structure of Poly[(2,6-di(2’,4’-dicarboxylphenyl)pyridine-κ4 O:O′:O″:O′′′)-(μ2-1,4-bis(1-imidazolyl)benzene-κ2N:N’)cobalt(II)],C_(39)H_(24)Co_(2)N_(7)O_(8)
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作者 Wang Yenan Liu Bo Niu Xiaoqing 《Plant Diseases and Pests》 CAS 2021年第1期38-43,共6页
[Objective]The paper was to synthesize a new structure of metal organic framework,and to provide new materials for plant pathogens testing.[Method]A mixture of 2,6-di(2’,4’-di-carboxylphenyl)pyridine,1,4-bis(1-imida... [Objective]The paper was to synthesize a new structure of metal organic framework,and to provide new materials for plant pathogens testing.[Method]A mixture of 2,6-di(2’,4’-di-carboxylphenyl)pyridine,1,4-bis(1-imidazolyl)benzene,Co(NO_(3))2·6H_(2)O were added to the solution of DMF:H2O=3:3 and heated at 433K for 4 d.[Result]Red crystals of the title compound were obtained(yield 76.3%,based on Co).[Conclusion]The crystal data were obtained as follows:C_(39)H_(24)Co_(2)N_(7)O_(8),monoclinic,P21/c,a=16.222(7)A,b=12.653(5)A,c=17.456(7)A,β=102.386(6)°,V=3500(2)A_(3),Z=4,Rgt(F)=0.0550,wRref(F2)=0.1509,T=293(2)K. 展开更多
关键词 Poly[(2 6-di(2’ 4’-dicarboxylphenyl)pyridine Cobalt(II)
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Synthesis and Crystal Structure of 4-(2- Chlorophenyl)-5-cyano-3-methyl-6-oxo-1- phenyl-4,5,6,7-tetrahydropyrazolo[3,4-b] Pyridine under Microwave Irradiation
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作者 朱松磊 屠树江 +4 位作者 李团结 邹翔 章晓镜 纪顺俊 张勇 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第11期1222-1225,共4页
The title compound (C20H15ClN4O, Mr = 362.81) was synthesized by the reaction of ethyl 2-cyano-3-(2-chlorophenyl)-1-acylate with 5-amino-3-methyl-1-phenylpyrazole under microwave irradiation and its structure was dete... The title compound (C20H15ClN4O, Mr = 362.81) was synthesized by the reaction of ethyl 2-cyano-3-(2-chlorophenyl)-1-acylate with 5-amino-3-methyl-1-phenylpyrazole under microwave irradiation and its structure was determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 8.8192(19), b = 15.976(3), c = 13.094(3) ? = 103.074(4), V = 1797.1(7) ?, Z = 4, Dc = 1.341 g/cm3, = 0.229 mm-1, F(000) = 752, R = 0.0632 and wR = 0.1278. X-ray analysis reveals that the pyridine ring adopts an envelope conformation. The dihedral angle between the pyrazole and pyridine planes is 2.19, and inter- molecular hydrogen bonds are also observed in the molecule. 展开更多
关键词 合成 晶体结构 4-(2-氯苯)-5-氰基-3-甲基-6-氧-1-苯基-4 5 6 7-四氢吡唑[3 4-b]嘧啶 微波辐射
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黄芩素抑制Toll样受体4/核因子-B炎症通路改善小鼠脑出血后脑损伤的作用及机制研究
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作者 王春喜 余永佳 +1 位作者 黄立添 冯大勤 《现代实用医学》 2023年第7期844-848,F0003,共6页
目的 探讨黄芩素抑制Toll样受体4(TLR4)/核因子-κB(NF-κB)炎症通路改善小鼠脑出血后脑损伤的作用及机制研究。方法 通过胶原酶注射小鼠右侧基底节区诱导小鼠脑出血,模型模型诱导后小鼠腹腔注射不同剂量黄芩素或者同体积溶剂,并通过神... 目的 探讨黄芩素抑制Toll样受体4(TLR4)/核因子-κB(NF-κB)炎症通路改善小鼠脑出血后脑损伤的作用及机制研究。方法 通过胶原酶注射小鼠右侧基底节区诱导小鼠脑出血,模型模型诱导后小鼠腹腔注射不同剂量黄芩素或者同体积溶剂,并通过神经功能学评分及脑水含量分析其保护作用;通过不同时间点给药(模型诱导后6及12h),评估黄芩素治疗时间窗;对TLR4和NF-κB信号通路的变化、小胶质细胞活化及神经细胞退变(FJC)进行检测。结果 黄芩素可减轻脑出血后脑水含量并改善神经功能学评分,并且模型诱导后6 h开始治疗,仍然有效;黄芩素可减少脑出血后神经细胞变性;黄芩素通过抑制小胶质细胞活化及TLR4/NF-κB通路及其下游促炎因子(TNF-α及IL-1β)的产生发挥抗炎作用。结论 黄芩素在脑出血后通过抗细胞死亡和抗炎作用发挥神经保护作用。 展开更多
关键词 脑出血 脑损伤 黄芩素 炎症 TOLL样受体4 核因子-b
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Studies on the Synthesis of Pyridine Analogs of the Natural Product3,5,4'-Trimethoxystilbene 被引量:2
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作者 Zhi Song PIAO Lin WANG Zhi Zhong ZHAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第11期1119-1122,共4页
Five pyridine analogs of the natural product, 3, 5, 4'-trimethoxystilbene, were synthesized. The final compounds were characterized by 1H-NMR.
关键词 SYNTHESIS pyridine analogs of 3 5 4'-trimethoxystilbene .
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佛手多糖对1-甲基-4-苯基-吡啶离子诱导人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用研究
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作者 陈进炫 龚舒 +3 位作者 刘天开 龚记熠 乙引 刘文华 《食品与发酵工业》 CAS CSCD 北大核心 2024年第8期17-23,共7页
该文探究佛手多糖对1-甲基-4-苯基-吡啶离子(1-methyl-4-phenyl-pyridine ion,MPP+)诱导人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用及其机制。佛手多糖经大孔吸附树脂AB-8进行纯化。体外培养SH-SY5Y细胞,构建帕金森病(Parkinson′s dis... 该文探究佛手多糖对1-甲基-4-苯基-吡啶离子(1-methyl-4-phenyl-pyridine ion,MPP+)诱导人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用及其机制。佛手多糖经大孔吸附树脂AB-8进行纯化。体外培养SH-SY5Y细胞,构建帕金森病(Parkinson′s disease,PD)细胞模型,实验分为对照组、MPP+模型组、佛手多糖组。采用噻唑蓝(methye thiazdye telrazlium,MTT)法检测细胞存活率,Hoechst33258染色法观察细胞形态,2′,7′-二氯荧光黄双乙酸盐荧光探针检测细胞活性氧(reactive oxygen species,ROS)水平,JC-1荧光探针法检测线粒体膜电位,蛋白免疫印迹(Western blot)检测磷酸化蛋白激酶B(phosphorylated protein kinase B,p-Akt)、蛋白激酶B(protein kinase B,Akt)、磷酸化细胞外调节蛋白激酶(phosphorylated extracellular regulated protein kinases1/2,p-ERK1/2)和细胞色素c(cytochrome c,Cyt-c)蛋白表达水平。结果表明,佛手多糖的得率4.86%,纯度为44.46%,经过AB-8纯化后,纯度提高到60.81%;与对照组相比,模型组细胞的存活率显著降低,Hoechst33258染色下可见细胞破碎,细胞核皱缩,细胞内ROS显著增加,线粒体膜电位显著降低。与模型组相比,佛手多糖组的细胞存活率显著增加,细胞形态明显得到改善,ROS水平下降,线粒体膜电位升高。Western blot结果显示,佛手多糖能抑制MPP+引起的p-Akt和p-ERK1/2的降低,以及Cyt-c的上升。综上,佛手多糖对MPP+诱导SH-SY5Y细胞损伤具有保护作用,其机制可能是通过调节线粒体ROS的产生和Cyt-c的释放,进而维持线粒体稳态,激活Akt信号通路和ERK信号通路,抑制细胞的凋亡,从而起到保护作用。研究结果可为缓解帕金森病的发生发展提供理论依据,同时也能更好地开发和利用佛手资源。 展开更多
关键词 佛手多糖 提取纯化 MPP+ SH-SY5Y细胞 保护作用
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Preparation and Electrochemical Properties of 3-Pyridinyl-6-aryl-1,2,4-triazolo [3,4-b][1, 3,4]thiadiazoles 被引量:3
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作者 TaiXIAO HuiXueLI +1 位作者 ChunXiaTAN MiaoCHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第3期335-337,共3页
关键词 PREPARATION 3-pyridinyl-6-aryl-1 2 4-triazolo[3 4-b][1. 3 4]thiadiazoles electro- chemical properties.
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A New Zn(Ⅱ) Coordination Polymer Constructed from 4-(1H-pyrazol-3-yl)pyridine as Fluorescent Sensor for Fe^(3+) 被引量:1
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作者 刘娜 邢广恩 +1 位作者 黄笑笑 郭靖 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第4期660-666,共7页
A new Zn(Ⅱ) coordination polymer, [Zn(4-PP)(1,4-BDC)?(H_2O)]_n(1, 4-PP = 4-(1 H-pyrazol-3-yl)pyridine, 1,4-H_2BDC = 1,4-benzenedicarboxylic acid), has been synthesized and structurally characterized by single-crystal... A new Zn(Ⅱ) coordination polymer, [Zn(4-PP)(1,4-BDC)?(H_2O)]_n(1, 4-PP = 4-(1 H-pyrazol-3-yl)pyridine, 1,4-H_2BDC = 1,4-benzenedicarboxylic acid), has been synthesized and structurally characterized by single-crystal X-ray diffraction as well as elemental analysis, IR spectra, XRPD and TG. Structural analysis reveals that Zn(Ⅱ) ions are bridged by COO-from 1,4-BDC^(2-)to form a binuclear structure as the second building units(SBUs). Zn_2 clusters can be clarified as 4-connected nodes, so the framework of 1 can be considered as a 2 D(44?62)-sql sheet. Fluorescence measurements show that 1 has highly selective and sensitive detection of Fe^(3+) in water medium. 展开更多
关键词 4-(1H-pyrazol-3-yl)pyridine crystal structure LUMINESCENCE sensor zinc complex
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2,6-双(1,2,3-三唑-4-基)吡啶钌(Ⅱ)的合成及其光催化性能的研究
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作者 刘佳欣 聂俊琦 《湖北大学学报(自然科学版)》 CAS 2024年第2期239-246,共8页
基于过渡金属的光催化体系,如钌(Ⅱ)或铱(Ⅲ)络合物,是一类具有广阔应用前景的光催化剂。本文中,我们报道一种新型钌(Ⅱ)络合物2,6-双(1,2,3-三唑-4-基)吡啶钌(Ⅱ)的合成,并通过核磁氢谱和碳谱证实其结构。该化合物在硫代氨基甲酸酯的... 基于过渡金属的光催化体系,如钌(Ⅱ)或铱(Ⅲ)络合物,是一类具有广阔应用前景的光催化剂。本文中,我们报道一种新型钌(Ⅱ)络合物2,6-双(1,2,3-三唑-4-基)吡啶钌(Ⅱ)的合成,并通过核磁氢谱和碳谱证实其结构。该化合物在硫代氨基甲酸酯的光合成中表现出良好的催化活性,底物兼容性好,产物收率在65%~82%之间。根据一系列的控制实验结果,我们阐述2,6-双(1,2,3-三唑-4-基)吡啶钌(Ⅱ)光催化硫醇和异氰偶联生成硫代氨基甲酸酯的反应机理。 展开更多
关键词 2 6-双(1 2 3-三唑-4-基)吡啶 光催化 异氰 氨基硫代甲酸酯
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基于4-羟基间苯二甲酸和含氮杂环配体的Zn(Ⅱ)配合物的合成、晶体结构与荧光性质研究
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作者 李波 王霏宇 +2 位作者 沈红 毛逢银 李勇辉 《人工晶体学报》 CAS 北大核心 2024年第4期692-700,共9页
在水热法条件下,4-羟基间苯二甲酸(H 2HPHA)和锌离子分别与1,2二(吡啶-4-基)乙烯(dpee)及4,4′-联吡啶(4,4′-bpy)反应得到了2个三维的配位聚合物[Zn(HPHA)(dpee)·(DMA)2]n(配合物1)和[Zn(HPHA)2(4,4′-bpy)2·DMA]n(配合物2)... 在水热法条件下,4-羟基间苯二甲酸(H 2HPHA)和锌离子分别与1,2二(吡啶-4-基)乙烯(dpee)及4,4′-联吡啶(4,4′-bpy)反应得到了2个三维的配位聚合物[Zn(HPHA)(dpee)·(DMA)2]n(配合物1)和[Zn(HPHA)2(4,4′-bpy)2·DMA]n(配合物2)。用X射线单晶衍射测定了配合物的晶体结构,结果显示:配合物1属于单斜晶系,C2空间群,每个不对称单元由一个锌离子,一个4-羟基间苯二甲酸配体及一个1,2-二(吡啶-4-基)乙烯组成;配合物2属于单斜晶系,P12/c1空间群,每个不对称单元由两个锌离子,两个4-羟基间苯二甲酸配体及两个4,4′-联吡啶配体组成。荧光光谱分析结果表明:配合物1的最强激发峰和发射峰在分别在251和397 nm,配合物2的最强激发峰和发射峰分别在415和513 nm。热重分析表明两个配合物在室温下稳定。 展开更多
关键词 锌配合物 4-羟基间苯二甲酸 1 2-二(吡啶-4-基)乙烯 4 4′-联吡啶 水热法 晶体结构 荧光光谱
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1,6-二氢-4-甲基-6-氧代-3-吡啶磺酰氯的合成工艺研究
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作者 周瑞 周志旭 +5 位作者 岳朝晨 张娅 李磊 高笛 鹿田 柴慧芳 《广东化工》 CAS 2024年第3期1-3,共3页
1,6-二氢-4-甲基-6-氧代-3-吡啶磺酰氯是一种重要医药化工中间体。本文以4-甲基-5-硝基吡啶-2-醇为原料,经两步反应得到目标化合物。该合成方法操作简便、后处理操作简便,花费时间少且产物纯度高,产品收率为33.51%;此方法为1,6-二氢-4-... 1,6-二氢-4-甲基-6-氧代-3-吡啶磺酰氯是一种重要医药化工中间体。本文以4-甲基-5-硝基吡啶-2-醇为原料,经两步反应得到目标化合物。该合成方法操作简便、后处理操作简便,花费时间少且产物纯度高,产品收率为33.51%;此方法为1,6-二氢-4-甲基-6-氧代-3-吡啶磺酰氯的合成提供了合成路线,也为进一步相关类似的合成研究奠定基础。 展开更多
关键词 4-甲基-5-硝基吡啶-2-醇 5-氨基-4-甲基吡啶-2-醇 合成 工艺 医药
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ZnO/g-C_(3)N_(4)异质结光催化材料的制备及对吡啶的降解
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作者 唐贝 《无机盐工业》 CAS CSCD 北大核心 2024年第4期133-142,共10页
采用蒸发溶剂-高温热聚合法制备了ZnO/g-C_(3)N_(4)异质结光催化材料,采用XRD、FTIR、TEM、XPS、UV-vis DRS、PL、TPC和EIS等表征技术对其进行了详细系统的表征,评价了ZnO/g-C_(3)N_(4)光催化降解吡啶的活性和稳定性,采用L_(9)(3^(4))... 采用蒸发溶剂-高温热聚合法制备了ZnO/g-C_(3)N_(4)异质结光催化材料,采用XRD、FTIR、TEM、XPS、UV-vis DRS、PL、TPC和EIS等表征技术对其进行了详细系统的表征,评价了ZnO/g-C_(3)N_(4)光催化降解吡啶的活性和稳定性,采用L_(9)(3^(4))正交实验考察了不同因素对光催化性能的影响,并对光催化机理进行了探讨。XPS和TEM结果证明了ZnO和g-C_(3)N_(4)之间异质结的形成,异质结的形成有效促进了光电子-空穴的分离,提高了光吸收,拓宽了光谱范围。在ZnO/g-C_(3)N_(4)复合光催化剂投加量为50 mg、ZnO与g-C_(3)N_(4)质量比为1∶2、吡啶初始质量浓度为20 mg/L和体系p H为7.0的条件下,可见光照射60 min后ZnO/g-C_(3)N_(4)对吡啶的光催化降解率达到了98.9%,循环使用5次后光催化降解率为97.3%,具有良好的稳定性。ZnO/g-C_(3)N_(4)光催化降解吡啶主要依赖于活性基团超氧自由基(·O_(2)^(-))和空穴(h^(+))的作用。 展开更多
关键词 ZnO/g-C_(3)N_(4) 光催化 异质结 吡啶
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CRYSTAL AND MOLECULAR STRUCTURE OF THE ADDUCT OF Ni(TAAB)(BF_4)_2WITH PYRIDINE
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作者 Ming Xing LI Zhong Zhi W U +2 位作者 Jiang Zhong ZHOU Zheng XU Xiao Zeng YOU Coordination Chemistry Institvte,Nanjing University,Nanjing 210008 Hua Qing WANG Yao YANG Center for Materials Aualysis of Nanjing University,Nanjing 210008 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第9期743-744,共2页
The crystal structure of [Ni(TAAB)(py)_2](BF_4)_2,where TAAB is the tetradentate macrocyclic ligand tetrabenzo[b,f,j,n] [1,5,9,13] tetraazacyclohexadecine,has been determined from X-ray diffraction analysis.The crys. ... The crystal structure of [Ni(TAAB)(py)_2](BF_4)_2,where TAAB is the tetradentate macrocyclic ligand tetrabenzo[b,f,j,n] [1,5,9,13] tetraazacyclohexadecine,has been determined from X-ray diffraction analysis.The crys. tai beiongs to monoclinic,space group P2_1/n with cell parameters a=16.465(6),b =12.486(5),e=20.219(1),β=113.79°, V=3803.9~3,Z=4,De=1.402 g/cm^3,F(000)=1640,The molecule has approximately S_4 symmetry.TAAB macrocyelic ligand presents a decidedly saddle-shaped appearance.Planes pyridine molecules are perpendicular to each other and the nickle(II)ion has coordination geometry.The final R and Rw are 0.068 and 0.070,respectively. 展开更多
关键词 BF4 TAAB pyridine CRYSTAL AND MOLECULAR STRUCTURE OF THE ADDUCT OF Ni
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Self-aggregating behavior of poly(4-vinyl pyridine)and the potential in mitigating sand production based onπ-πstacking interaction
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作者 Jian-Da Li Gui-Cai Zhang +4 位作者 Ji-Jiang Ge Wen-Li Qiao Hong Li Ping Jiang Hai-Hua Pei 《Petroleum Science》 SCIE CAS CSCD 2022年第5期2165-2174,共10页
Unconsolidated sandstone reservoirs are most susceptible to sand production that leads to a dramatic oil production decline.In this study,the poly(4-vinyl pyridine)(P_(4)VP)incorporated with self-aggregating behavior ... Unconsolidated sandstone reservoirs are most susceptible to sand production that leads to a dramatic oil production decline.In this study,the poly(4-vinyl pyridine)(P_(4)VP)incorporated with self-aggregating behavior was proposed for sand migration control.The P_(4)VP could aggregate sand grains spontaneously throughπ-πstacking interactions to withstand the drag forces sufficiently.The influential factors on the self-aggregating behavior of the P_(4)VP were evaluated by adhesion force test.The adsorption as well as desorption behavior of P_(4)VP on sand grains was characterized by scanning electron microscopy and adhesion force test at different pH conditions.The result indicated that the pH altered the forms of surface silanol groups on sand grains,which in turn affected the adsorption process of P_(4)VP.The spontaneous dimerization of P_(4)VP molecules resulting from theπ-πstacking interaction was demonstrated by reduced density gradient analysis,which contributed to the self-aggregating behavior and the thermally reversible characteristic of the P_(4)VP.Dynamic sand stabilization test revealed that the P_(4)VP showed wide pH and temperature ranges of application.The production of sands can be mitigated effectively at 20-130℃ within the pH range of 4-8. 展开更多
关键词 Self-aggregating Poly(4-vinyl pyridine) π-πstacking Sand migration control
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Synthesis, Characterization and Crystal Structure of Cobalt(II) Complex of a Schiff Base Derived from Isoniazid and Pyridine-4-Carboxaldehyde
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作者 Evans N. Mainsah Sally-Judith E. Ntum +3 位作者 Mariam Asseng Conde George T. Chi James Raftery Peter T. Ndifon 《Crystal Structure Theory and Applications》 2019年第4期45-56,共12页
A new hydrogen bonded Cobalt(II) Schiff base complex,?N’-(pyridine-4-carboxaldehyde) isonicotinoylhydrazone Cobalt(II), has been synthesized from isoniazid and pyridine-4-carboxaldehyde and characterized by IR spectr... A new hydrogen bonded Cobalt(II) Schiff base complex,?N’-(pyridine-4-carboxaldehyde) isonicotinoylhydrazone Cobalt(II), has been synthesized from isoniazid and pyridine-4-carboxaldehyde and characterized by IR spectroscopy, 1H-NMR, elemental analysis, TGA and single crystal X-ray structure determination. X-ray crystal structure analysis shows an octahedral complex with a metal centre coordinated to two ligand molecules through the pyridine nitrogen atoms and four water molecules and containing two nitrate groups as counter ions. The complex crystallizes in the monoclinic crystal system and P2(1)/n space group. The unit cell dimensions are: a = 7.2108(4) &Aring;, b = 16.6020(9) &Aring;, c = 13.0389(6) &Aring;,α = 90°, β = 103.972(4)°, γ = 90°. The molecule is symmetrical about the cobalt centre as observed from the 1H-NMR and 13C-NMR and confirmed by the single crystal X-ray structure of the complex. Thermogravimetric analysis shows two steps decomposition of the complex to leave a metal oxide residue. The title compound is expected to be biologically active as one of the precursors (isoniazid) is a therapeutic agent with well-established clinical applications. 展开更多
关键词 pyridine Derivatives Cobalt(II) COMPLEX Isonicotinoylhydrazone pyridine-4-Carboxaldehyde Schiff Base HETEROCYCLIC Compound X-Ray Structure
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