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Synthesis and Crystal Structure of (E)-ethyl 6-benzyl-2-[(cyclopropylmethylamino)(4-fluorophenylamino)-methyleneamino]-4,5,6,7-tetrahydrothieno[2,3-c]pyridine-3-carboxylate ethanol monosolvate 被引量:2
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作者 陈鸿 刘明国 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第7期959-964,共6页
The crystal structure of the new title compound (E)-ethyl 6-benzyl-2-[(cyclopropylmethylamino)(4-fluorophenylamino)methyleneamino]-4,5,6,7-tetrahydrothieno[2,3-c]pyridine-3-carboxylate ethanol monosolvate (C28H... The crystal structure of the new title compound (E)-ethyl 6-benzyl-2-[(cyclopropylmethylamino)(4-fluorophenylamino)methyleneamino]-4,5,6,7-tetrahydrothieno[2,3-c]pyridine-3-carboxylate ethanol monosolvate (C28H31FN 4O2S·C2H6O, Mr=552.70) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic system, space group P21/c with a=13.806(10), b=10.850(7), c=19.938(14), β=98.842(9)° , V=2951(4)3 , Z=4, Dc=1.244g/cm 3 , F(000)=1176, μ=0.153 mm-1 , MoKα radiation (λ=0.71073), R=0.0758 and wR=0.2234 for 4262 observed reflections with I 〉 2σ(I). Intramolecular N-H…S and C-H…N interactions as well as intermolecular N-H…O and O-H…N hydrogen bonds help to stabilize the crystal structure. X-ray diffraction analysis reveals that the asymmetric unit contains one title molecule and one ethanol molecule. 展开更多
关键词 crystal structure thieno[2 3-c]pyridine aza-Wittig reaction synthe is
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Broad-Spectrum Antiproliferative Activity of Diarylureas and Diarylamides Possessing Pyrrolo[3,2-c]Pyridine Scaffold
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作者 Mohammad Ashrafuddin Khan Mohammed I. EI-Gamal +3 位作者 Mohammed S. Abdel-Maksoud Mahmoud M.Gamal El-Din Kyung Ho Yoo Chang-Hyun Oh 《Journal of Pharmacy and Pharmacology》 2014年第3期157-169,共13页
A series of diarylureas and diarylamides possessing pyrrolo[3,2-c]pyridine scaffold was designed and synthesized. Their in vitro antiproliferative activities were tested against a panel of 49 cell lines of eight diffe... A series of diarylureas and diarylamides possessing pyrrolo[3,2-c]pyridine scaffold was designed and synthesized. Their in vitro antiproliferative activities were tested against a panel of 49 cell lines of eight different cancer types at the NCI and compared with Sorafenib as a reference compound. Most of the compounds showed strong and broad-spectrum antiproliferative activities with superior potencies to Sorafenib. Compounds 8a, 9d and 9f showed lethal effect with mean %inhibition more than 100% over the 49 tested cell lines. In addition, the mean %inhibition results of compounds 8d, 8e, 9e, 9g and 9h were more than 80%. And most of the IC50 values of the target compounds were in submicromolar scale. Compounds 8a, 9b and 9e demonstrated high selectivity towards cancer cell lines compared with NIH3T3 fibroblasts. 展开更多
关键词 ANTICANCER ANTIPROLIFERATIVE diarylamide diarylurea pyrrolo[3 2-c]pyridine.
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An effcient synthesis of functionalized tetrahydro-1H-indeno[2,1-c]pyridine derivatives by a PPh_3-promoted condensation reaction between acetylene esters and 1,3-dioxo-N-aryl-2,3-dihydro-1H-indene-2-carboxamides 被引量:1
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作者 Mohammad Hossein Mosslemin Nasim Shams +1 位作者 Hossein Esteghamat Hossein Anaraki-Ardakani 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第12期1095-1098,共4页
A reaction between 1,3-dioxo-N-aryl-2,3-dihydro-lH-indene-2-carboxamides, dialkyl acetylenedicar- boxylates, and triphenylphosphine or trimethylphosphite is described as a simple and efficient method for the synthesis... A reaction between 1,3-dioxo-N-aryl-2,3-dihydro-lH-indene-2-carboxamides, dialkyl acetylenedicar- boxylates, and triphenylphosphine or trimethylphosphite is described as a simple and efficient method for the synthesis of 5-hydroxy-4-aryl-2,5-dihydrofuran-2,3-dicarboxylate derivatives. 展开更多
关键词 Dialkyl acetylenedicarboxylates Triphenylphosphine Trimethylphosphites Tetrahydro-1H-indeno[2 1 -c]pyridine
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一个新的三维超分子配位聚合物[Ni(pyridine-2-carboxylate)2]n·2nH2O的水热合成及晶体结构 被引量:7
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作者 李秀梅 牛艳玲 +1 位作者 刘博 周实 《分子科学学报》 CAS CSCD 北大核心 2009年第1期60-63,共4页
采用水热法合成了一个新的金属-有机配位聚合物[Ni(pyridine-2-carboxylate)2]n.2nH2O,对其进行元素分析、红外光谱和X射线单晶衍射测定.结构分析表明:该晶体属于三斜晶系,P-1空间群,晶胞参数a=5.1284(6)nm,b=7.6346(9)nm,c=9.2295(11)... 采用水热法合成了一个新的金属-有机配位聚合物[Ni(pyridine-2-carboxylate)2]n.2nH2O,对其进行元素分析、红外光谱和X射线单晶衍射测定.结构分析表明:该晶体属于三斜晶系,P-1空间群,晶胞参数a=5.1284(6)nm,b=7.6346(9)nm,c=9.2295(11)nm,α=74.902(2)°,β=84.347(2)°,γ=71.442(2)°,V=330.70(7)nm3,化学式为C12H12NiN2O6,Mr=338.95,Dc=1.702g/cm3,μ(Mo,Kα)=1.497mm-1,F(000)=174,Z=1,R=0.0333,wR=0.0384((I>2σ(I)).并且该配合物通过O—H…O和C—H…O氢键形成了三维超分子网状结构. 展开更多
关键词 水热合成 超分子网状结构 吡啶-2-羧酸
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Synthesis and Anti-leukemia Evaluation of Tetrahydro-4H-pyrano[3,2-c]pyridines and Corresponding Anti-CD14 Monoclonal Antibody Conjugates
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作者 SUN Chuan-wen WANG Jing PANG Chun-cheng LI Jing XIAO Di 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2013年第6期1104-1109,共6页
A series of novel tetrahydro-4H-pyrano[3,2-c]pyridines(3a-3p) were synthesized and found to possess potent antiproliferative activity against leukemia K562 cells in vitro. Preliminary bioassay indicates that compoun... A series of novel tetrahydro-4H-pyrano[3,2-c]pyridines(3a-3p) were synthesized and found to possess potent antiproliferative activity against leukemia K562 cells in vitro. Preliminary bioassay indicates that compounds 3a and 3e afford the best activity, the IC50 values of them were 6.93 and 7.51μg/mL, respectively, which were lower than that of the anticancer drug 5-FU(1C50=8.56μg/mL). To reduce the toxicity of compounds 3a-3p to the prolife- ration of normal bematopoietic cells, a tumor targeted CD14 monoclonal antibody(McAb) was used in conjugation with compounds 3a--3p to get conjugates 4a--4p, respectively. The inhibitory activities of conjugates 4a--4p toward K562 cells were discovered to approach those of compounds 3a--3p. In the presence of CD14 McAb, tumor cells were found to be much more susceptible to conjugates 3a--3p than normal hematopoietic cells. Therefore, the toxicity of conjugates 4a--4p to normal hematopoietic cells declined obviously. For example, as for the toxicity of compound 3a compared with that of compound 4a, the value of ICs0 increased from 35.90 μmol/L to 39.52 μmol/L. 展开更多
关键词 Tetrahydro-4H-pyrano[3 2-c]pyridine Leukemia K562 cell Anti-cDl4 monoclonal antibody(McAb) Conjugate Inhibitory Toxicity
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CuI-pyridine-β-CD包合物的合成、表征及应用
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作者 董瑞风 乔洁 +3 位作者 唐胜男 李笃信 双少敏 董川 《应用化工》 CAS CSCD 2010年第5期637-640,644,共5页
为了改善CuI-pyridine配合物的物理性质,采用溶液搅拌法合成了CuI-pyridine配合物与β-CD的包合物,用IR、1HNMR、荧光光谱等分析方法对其进行了表征,并用电分析方法初步研究了各种气体对包合物修饰膜电极的响应。结果表明,CuI-pyridine-... 为了改善CuI-pyridine配合物的物理性质,采用溶液搅拌法合成了CuI-pyridine配合物与β-CD的包合物,用IR、1HNMR、荧光光谱等分析方法对其进行了表征,并用电分析方法初步研究了各种气体对包合物修饰膜电极的响应。结果表明,CuI-pyridine-β-CD包合物为水溶性的荧光化合物(固体状态时EMmax=563 nm),荧光发射稳定;随着甲烷气体不断通入,包合物荧光强度逐渐降低,且甲烷气体对CuI-pyridine-β-CD包合物膜有显著的响应。 展开更多
关键词 CUI 吡啶 -βCD 包合物 合成
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A Facile Approach for Synthesis of Benzofuro[2,3-c]pyridines via Intramolecular Cascade Annulations
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作者 Ying Duan Ye Wang Dongmi Li 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2014年第11期1103-1106,共4页
A facile synthesis of benzofuro[2,3-c]pyridines has been achieved under mild conditions by using ammonium acetate as the nitrogen source through intramolecular cascade annulation.This reaction could efficiently constr... A facile synthesis of benzofuro[2,3-c]pyridines has been achieved under mild conditions by using ammonium acetate as the nitrogen source through intramolecular cascade annulation.This reaction could efficiently construct pyridine ring and furan ring in one step.Moreover,the key annulation step was demonstrated through dihydrobenzofuran intermediates. 展开更多
关键词 benzofuro[2 3-c]pyridines intramolecular cascade annulation ammonium acetate
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Synthesis of a new pyridine-containing diamine and related polyimide 被引量:4
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作者 Zhao, Jiu Jiang Gong, Chen Liang +2 位作者 Zhang, Shu Jiang Shao, Yu Li, Yan Feng 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期277-278,共2页
A new kind of aromatic diamine monomer containing pyridine unit,2,6-bis[4-(4-aminophenoxy)phenoxy]pyridine(BAPP),was synthesized in three steps,using hydroquinone as starting material.A novel pyridine-containing polyi... A new kind of aromatic diamine monomer containing pyridine unit,2,6-bis[4-(4-aminophenoxy)phenoxy]pyridine(BAPP),was synthesized in three steps,using hydroquinone as starting material.A novel pyridine-containing polyimide was prepared from the resulting diamine BAPP with 4,4 -oxydiphthalic anhydride(ODPA) via a conventional two-step thermal imidization method.The resulting polyimide exhibits excellent solubility,film-forming capability and high thermal resistance. 展开更多
关键词 pyridine Aromatic polyimide pyridine-containing diamine
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Kinetic hydrate inhibitor performance of new copolymer poly(N-vinyl-2-pyrrolidone-co-2-vinyl pyridine)s with TBAB 被引量:8
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作者 Jun Hu Sijia Li +3 位作者 Yanhong Wang Xuemei Lang Qingping Li Shuanshi Fan 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第2期126-131,共6页
In oil and gas field, the application of kinetic hydrate inhibitors (KHIs) independently has remained problematic in high subcooling and high water-cut situation. One feasible method to resolve this problem is the c... In oil and gas field, the application of kinetic hydrate inhibitors (KHIs) independently has remained problematic in high subcooling and high water-cut situation. One feasible method to resolve this problem is the combined use of KHIs and some synergists, which would enhance KHIs’ inhibitory effect on both hydrate nucleation and hydrate crystal growth. In this study, a novel kind of KHI copolymer poly(N-vinyl-2-pyrrolidone-co-2-vinyl pyridine)s (HGs) is used in conjunction with TBAB to show its high performance on hydrate inhibition. The performance of HGs with different monomer ratios in structure II tetrahydrofuran (THF) hydrate is investigated using kinetic hydrate inhibitor evaluation apparatus by step-cooling method and isothermal cooling method. With the combined gas hydrate inhibitor at the concentration of 1.0 wt%, the induction time of 19 wt% THF solution could be prolonged to 8.5 h at a high subcooling of 6℃. Finally, the mechanism of HGs inhibiting the formation of gas hydrate is proposed. 展开更多
关键词 clathrate hydrate kinetic hydrate inhibitors combined hydrate inhibitors poly(N-vinyl-2-pyrrolidone-co-2-vinyl pyridine
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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
An efficient and novel procedure for the preparation of pyrazolo[3,4-b]pyridine derivatives through multi-component reaction of aldehyde, 5-amino-3-methyl-1-phenylpyrazole and malononitrile or cyanoacetate in [bmim][B... An efficient and novel procedure for the preparation of pyrazolo[3,4-b]pyridine derivatives through multi-component reaction of aldehyde, 5-amino-3-methyl-1-phenylpyrazole and malononitrile or cyanoacetate in [bmim][BF4] is described in this paper. Advantages of the method presented here include mild conditions, high yields together with a green nature and ease of recovery and reuse of the reaction medium. 展开更多
关键词 Pyrazolo[3 4-b]pyridine Multi-component reaction Ionic liquid
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Synthesis,Crystal Structure and Antifungal Activity of 8-Chloro-3-((4-chlorobenzyl)-thio)[1,2,4]triazolo[4,3-a]pyridine 被引量:2
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作者 汪乔 翟志文 +3 位作者 孙召慧 刘幸海 谭成侠 翁建全 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第4期651-655,共5页
The title compound 8-chloro-3-((4-chlorobenzyl)thio)-[1,2,4]triazolo[4,3-a]pyridine was prepared from 1-chloro-4-(chloromethyl)benzene and 8-chloro-[1,2,4]triazolo[4,3-a]pyridine-3(2H)-thione in the presence o... The title compound 8-chloro-3-((4-chlorobenzyl)thio)-[1,2,4]triazolo[4,3-a]pyridine was prepared from 1-chloro-4-(chloromethyl)benzene and 8-chloro-[1,2,4]triazolo[4,3-a]pyridine-3(2H)-thione in the presence of Na OH, and its structure was determined by X-ray diffraction analysis. The crystal is of triclinic system, space group P1 with a = 6.8264(6), b = 7.5890(4), c = 13.0960(7) A, α = 93.447(4), β = 98.772(6), γ = 92.615(6)o, V = 668.26(8) A3, Z = 2, the final R = 0.035 and wR = 0.09 for 2259 observed reflections with I 〉 2σ(I). The preliminary biological test showed that the title compound has activities against Stemphylium lycopersici(Enjoji) Yamamoto, Fusarium oxysporum. sp. cucumebrium, and Botrytis cinerea with inhibitory to be 51.19%, 62.02% and 15.56%, respectively. 展开更多
关键词 1 2 4-triazolo[4 3-a]pyridine synthesis crystal structure antifungal activity
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CuⅡ and CuⅠ Complexes of 1,1'-(Pyridin-2-ylmethylene)-bis[3-(pyridin-2-yl)imidazo[1,5-a]pyridine]:in situ Generation of the Ligand via Acetic Acid-controlled Metal-ligand Reactions 被引量:2
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作者 张海峰 陈砚美 +2 位作者 秦亚茹 李亚红 李武 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第9期1417-1427,共11页
Reaction of 3-(pyridin-2-yl)-imidazo[1,5-a]pyridine (HPIP), CuCi2·2H20 and picolinaldehyde in the mixture of CHaCOOH and EtOH under solvothermal conditions gave complexes [LCuCI][CuECI3] (1) and [HLCuC1]E[C... Reaction of 3-(pyridin-2-yl)-imidazo[1,5-a]pyridine (HPIP), CuCi2·2H20 and picolinaldehyde in the mixture of CHaCOOH and EtOH under solvothermal conditions gave complexes [LCuCI][CuECI3] (1) and [HLCuC1]E[CuCI2]2[CuCI3].2H20 (2) (L = 1,1'-(pyridin-2- ylmethylene)bis[3-(pyridin-2-yl)imidazo[1,5-a]pyridine]) simultaneously. The ligand L was generated via in situ metal-ligand reaction between HPIP and picolinaldehyde. When CuCI2·2H20 was replaced by CuC1, the 2:1:1(HPIP:picolinaldehyde:CuCI) reaction afforded complex [CuaL2CI2][CuCI2]·2H20 (3) and the analogous 2:1:3 reaction generated compound [CuaL2][CuCI2]3 (4). Complexes 1 and 2 are Cun/CuI mixed-valence compounds. Complexes 1-4 display four various structures. It is found that the formation of the L ligand is controlled by CH3COOH. This work reveals that the structures of complexes 1-4 could be rationally tuned via the inclusion of CH3COOH in the reaction systems, the proper selection of different starting materials and the dexterous adjustment of the ratio of the starting materials. 展开更多
关键词 Imidazo[1 5-a]pyridine coordination chemistry CuII complex
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Synthesis and Characterization of Polyamide-Containing 2, 6-(Substituded) pyridine Derivatives 被引量:1
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作者 XU Kuoxi HU Peizhi CAI Lihua 《Wuhan University Journal of Natural Sciences》 CAS 2006年第3期682-686,共5页
A new series of acyelic aromatic polyamide pyridine derivatives a-h and a new macrocyclic polyamide containing pyridine ring i were synthesized by the reaction of N^2, N^6-his(2-aminoethyl) pyridine-2, 6-dicarboxami... A new series of acyelic aromatic polyamide pyridine derivatives a-h and a new macrocyclic polyamide containing pyridine ring i were synthesized by the reaction of N^2, N^6-his(2-aminoethyl) pyridine-2, 6-dicarboxamide or N^2 , N^6-bis (3-aminopropyl) pyridine-2,6-dicarboxamide with various acyl chloride. The compounds were characterized by MS, ^1H NMR, IR and elemental analysis. The single-crystal structure of g confirmed that the crystal is of triclinic, space group P-1 with Mr = 487.55, α=9.3031(19), b=12.167(2) , c=126.50(3) nm, α=108.91(3)°, β= 97. 57(3)°, γ=102.07(3)°, Ⅴ= 1 293.5 nm, Z=2, Dc=1. 252 kg/m^3, μ=0. 086 mm^-1, F(000)=516, X-ray analysis reveals that there exist hydrogen bonding and network structure in the crystal. 展开更多
关键词 POLYAMIDE pyridine derivative synthesis crystal structure
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One-Pot Three-Component Synthesis of Imidazo[1,5-<i>a</i>]pyridines 被引量:2
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作者 Abbas Rahmati Zahra Khalesi 《International Journal of Organic Chemistry》 2011年第2期15-19,共5页
A one-pot three component condensation synthesis of imidazo[1,5-a]pyridines using of various aromatic aldehydes and dipyridil ketone with ammonium acetate in the presence of Lithium chloride as catalyst in good yields... A one-pot three component condensation synthesis of imidazo[1,5-a]pyridines using of various aromatic aldehydes and dipyridil ketone with ammonium acetate in the presence of Lithium chloride as catalyst in good yields under microwave irradiation has been described. 展开更多
关键词 Lithium Chloride Imidazo[1 5-a]pyridine Microwave Irradiation
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Theoretical Investigation on the Stability and Reactivity of Imidazo [1,2-a] Pyridine N-Acylhydrazone Derivatives Using Density Functional Theory
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作者 Camara Tchambaga Etienne Sangare Kassoum +4 位作者 Dosso Ouehi Ablo Evrard Sekou Diomande Souleymane Coulibaly Siomenan Coulibali 《Computational Chemistry》 CAS 2024年第1期1-23,共23页
The reactivity and stability of seventeen (17) imidazo [1,2-a]pyridine N-acylhydrazone derivatives were investigated using density functional theory at the B3LYP/6-31+ G (d, p) level. Analysis of the molecular electro... The reactivity and stability of seventeen (17) imidazo [1,2-a]pyridine N-acylhydrazone derivatives were investigated using density functional theory at the B3LYP/6-31+ G (d, p) level. Analysis of the molecular electrostatic potential (MEP) and determination of the dual descriptor revealed that in most cases, the nitrogen atoms of the 6-πelectron conjugation, the oxygen, and the sulfur atom are nucleophilic site. Chemical reactivity of the compounds was assessed through analysis of frontier molecular orbitals (HOMO and LUMO), energy gap (Δℰ), chemical hardness (η), and the softness (S). Consequently, the compound 9e exhibited the lowest reactivity, least electron donating, and the highest stability. This comprehensive study offers valuable insights into the chemical behavior of these derivatives, crucial for further exploration and potential applications. 展开更多
关键词 N-Acylhydrazones Imidazo [1 2-a] pyridine DFT Molecular Electrostatic Potential REACTIVITY Stability
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Syntheses,structures,and properties of three coordination polymers based on 5⁃ethylpyridine⁃2,3⁃dicarboxylic acid and N⁃containing ligands
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作者 TANG Long BIAN Yaxin +3 位作者 CHEN Luyuan HOU Xiangyang WANG Xiao WANG Jijiang 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第10期1975-1985,共11页
Three coordination polymers[Mn(epda)(2,2'⁃bipy)(H_(2)O)](1),[Mn(epda)(phen)](2),and[Co_(2)(epda)2(bpe)2(H_(2)O)_(4)]·5H_(2)O(3)(H2epda=5⁃ethyl⁃pyridine⁃2,3⁃dicarboxylic acid,2,2'⁃bipy=2,2'⁃bipyridine,... Three coordination polymers[Mn(epda)(2,2'⁃bipy)(H_(2)O)](1),[Mn(epda)(phen)](2),and[Co_(2)(epda)2(bpe)2(H_(2)O)_(4)]·5H_(2)O(3)(H2epda=5⁃ethyl⁃pyridine⁃2,3⁃dicarboxylic acid,2,2'⁃bipy=2,2'⁃bipyridine,phen=phenanthroline,bpe=1,2⁃bis(4⁃pyridyl)ethylene)were synthesized by solvothermal reactions and characterized by single⁃crystal X⁃ray diffraction,thermogravimetric analyses,IR spectroscopy and elemental analysis.1 displays a 1D chain struc⁃ture,and these chains are joined by O-H…O hydrogen bonding andπ⁃πstacking interactions to generate a 2D layer structure.2 displays a 2D layer structure,and adjacent layers are generated 3D architecture throughπ⁃πstacking interactions.3 displays a 1D chain structure,and adjacent chains are generated double layer structure through O-H…O hydrogen bonding.The fluorescent properties of 1 and 3 indicate that they can potentially be used as a luminescent sensor.1 was highly selective and sensitive towards o⁃nitrophenol through different detection mechanisms,however,3 was highly selective and sensitive towards 2,4,6⁃trinitrophenol.In addition,the magnetic behavior of 2 has also been investigated.CCDC:2172533,1,2355773,2,2355774,3. 展开更多
关键词 coordination polymers 5⁃ethyl⁃pyridine⁃2 3⁃dicarboxylate ligand crystal structures fluorescent properties magnetic behavior
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Lignin‐derived carbon with pyridine N‐B doping and a nanosandwich structure for high and stable lithium storage
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作者 Dichao Wu Jiayuan Li +5 位作者 Yuying Zhao Ao Wang Gaoyue Zhang Jianchun Jiang Mengmeng Fan Kang Sun 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期232-247,共16页
Biomass‐derived carbon is a promising electrode material in energy storage devices.However,how to improve its low capacity and stability,and slow diffusion kinetics during lithium storage remains a challenge.In this ... Biomass‐derived carbon is a promising electrode material in energy storage devices.However,how to improve its low capacity and stability,and slow diffusion kinetics during lithium storage remains a challenge.In this research,we propose a“self‐assembly‐template”method to prepare B,N codoped porous carbon(BN‐C)with a nanosandwich structure and abundant pyridinic N‐B species.The nanosandwich structure can increase powder density and cycle stability by constructing a stable solid electrolyte interphase film,shortening the Li^(+) diffusion pathway,and accommodating volume expansion during repeated charging/discharging.The abundant pyridinic N‐B species can simultaneously promote the adsorption/desorption of Li^(+)/PF_(6)^(−) and reduce the diffusion barrier.The BN‐C electrode showed a high lithium‐ion storage capacity of above 1140 mAh g^(−1) at 0.05 A g^(−1) and superior stability(96.5% retained after 2000 cycles).Moreover,owing to the synergistic effect of the nanosandwich structure and pyridinic N‐B species,the assembled symmetrical BN‐C//BN‐C full cell shows a high energy density of 234.7Wh kg^(−1),high power density of 39.38 kW kg−1,and excellent cycling stability,superior to most of the other cells reported in the literature.As the density functional theory simulation demonstrated,pyridinic N‐B shows enhanced adsorption activity for Li^(+) and PF_(6)^(−),which promotes an increase in the capacity of the anode and cathode,respectively.Meanwhile,the relatively lower diffusion barrier of pyridinic N‐B promotes Li^(+) migration,resulting in good rate performance.Therefore,this study provides a new approach for the synergistic modulation of a nanostructure and an active site simultaneously to fabricate the carbon electrode material in energy storage devices. 展开更多
关键词 high cycling stability high energy density lithium‐ion batteries pyridinic N‐B species sandwich structure carbon nanosheet
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A convenient one-pot synthesis of new chromeno[3,4-c]chromene and chromeno[3,4-c]pyridine derivatives in the presence of high surface area of magnesium oxide 被引量:2
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作者 Iman Mohammadzadeh Hassan Sheibani 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第12期1327-1330,共4页
In this investigation a new strategy involves the one-pot, three-component reaction of malononitrile, salycilaldehyde and phenol derivatives in the presence of high surface area of MgO is extended to the formation of ... In this investigation a new strategy involves the one-pot, three-component reaction of malononitrile, salycilaldehyde and phenol derivatives in the presence of high surface area of MgO is extended to the formation of chromeno[3,4-c]ehromene derivatives in good to excellent yields in a short reaction time. Also, the three component reactions of an aldehyde such as salycilaldehyde and ketones with malononitril for the formation of chromeno[3,4-c]pyridines are investigated. 展开更多
关键词 Salycilaldehyde Chromeno[3 4-c]chromenes 2-Amino-4-aryl pyddylcyanides malononitrile
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Synthesis, Crystal Structure and DNA-Binding Property of a Mn(Ⅱ) Complex Based on 5-(Tri-fluoromethyl)pyridine-2-carboxylic Acid 被引量:4
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作者 WANG Jia-Kai LI Bing +2 位作者 WU Huan-Ping TIAN Xiao-Yan MA Xiao-Xia 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第8期1349-1355,共7页
A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic ... A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic system, space group P■ with a = 5.0885(10), b = 6.5574(13), c = 14.016(3) ?, β = 90.67(3)o, V = 436.34(17) ?3, Z = 1, Dc = 1.793 g·cm-3, μ = 0.855 mm-1, Mr = 471.18, F(000) = 235, the final R = 0.0454 and wR = 0.1134 for 1998 observed reflections with I > 2σ(I). The Mn(Ⅱ) ion is coordinated by two N and two O atoms from two Htpc as well as two O atoms from two coordinated water molecules, forming a 0D motif with distorted octahedral coordinate geometry. The adjacent 0D units are linked into 1D chains through hydrogen bond O(1W)–H(1 WB)···O(2), and via the O(1 W)–H(1 WA)···O(1) hydrogen bond the neighboring 1D chains are connected into a 2D supramolecular layer. Moreover, the interactions between the ligand and its complex with CT-DNA were studied by EtBr fluorescence probe, which suggested that these compounds bind to CT-DNA through an intercalation mode. The binding constants were 0.41 and 0.64 for Htpc and complex 1, respectively. It indicates that the interaction between complex 1 and CT-DNA is stronger than Htpc. 展开更多
关键词 5-(trifluoromethyl)pyridine-2-carboxylic acid crystal structure DNA fluorescence SPECTRA
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Synthesis and Crystal Structure of Diethyl-2,6-dimethyl-3,5-diyl-(1-(2-chlorobenzoyl)-1H- pyrazole-3-diethyl-carboxylate)-pyridine
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作者 钱群 张敏 +4 位作者 李志芬 曹卫国 张军 邵敏 夏义本 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第10期1163-1166,共4页
The reaction of hydrazine hydrate with a new α,γ-diketone ester 3, derived from the reaction of 2,6-dimethyl-3,5-diacetyl-pyridine 2 with diethyl oxalate in the presence of sodium ethoxide, afforded the pyrazole der... The reaction of hydrazine hydrate with a new α,γ-diketone ester 3, derived from the reaction of 2,6-dimethyl-3,5-diacetyl-pyridine 2 with diethyl oxalate in the presence of sodium ethoxide, afforded the pyrazole derivative 4. Treatment of 4 with 2-chlorobenzoyl chloride gave diethyl 2,6-dimethyl-3,5-diyl-(1-2(chlorobenzoyl)-1H-pyrazole-3-diethyl-carboxylate) pyridine 5. Fine crystal of 5 suitable for XRD analysis was obtained form recrystalization in ethyl acetate. The crystal belongs to the triclinic system, space group P1^-, with a = 1.0342(11), b = 1.2211(12), c = 1.5013(15) nm, α = 82.5190(10),β = 85.7960(10),γ = 85.3150(10)°, V= 1.8697(3) nm^3, Dc= 1.173 g/cm^3, μ = 0.219 mm^-1, F(000) = 684, Z = 2, the final R = 0.0720 and wR = 0.2211. 展开更多
关键词 pyridine PYRAZOLE N-ACYLATION crystal structure
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