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Synthesis,Crystal Structure,and Magnetic Property of One 3D Nickel Coordination Polymer Based on 2-Hydroxy-5-(3',5'-terephthalic acid)Pyridine and 1,4-Bis(1-imdazoly)benzene 被引量:1
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作者 TANG Pei-Qin HAO Lu-Jiang +3 位作者 FAN Li-Ming LIU Xin-Zheng LI Bin ZHANG Xiu-Tang 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第10期1519-1524,共6页
One novel nickel coordination polymer, {[Ni(OTP)(bib)1.5(H2O)]·2H2O}n(1, H2 OTP = 2-hydroxy-5-(3',5'-terephthalic acid) pyridine, bib = 1,4-bis(1-imdazoly)benzene), has been synthesized and characte... One novel nickel coordination polymer, {[Ni(OTP)(bib)1.5(H2O)]·2H2O}n(1, H2 OTP = 2-hydroxy-5-(3',5'-terephthalic acid) pyridine, bib = 1,4-bis(1-imdazoly)benzene), has been synthesized and characterized by elemental analysis(EA), IR, powder X-ray diffraction(PXRD), and thermogravimetric(TG) analyses. The crystal of 1 crystallizes in monoclinic, space group P21/n with a = 12.2860(5), b = 13.8246(6), c = 19.0140(8) A, β = 104.3870(1)°, V = 3128.2(2) A3, Z = 4, C32H28N7 Ni O8, Mr = 697.32, Dc = 1.481 g/cm^3, F(000) = 1444 and μ(Mo Kα) = 0.684 mm-1. The final R = 0.0704 and w R = 0.1764 for 5485 observed reflections with I 2σ(I) and R = 0.1087 and wR = 0.2010 for all data. Topology analysis reveals that complex 1 is a 3D 2-fold interpenetrated {4^4·6^6}-nov net based on the 1D [Ni(OTP)]n chain and the 2D [Ni2(bib)3]n sql sheet. And the variable-temperature magnetic susceptibility measurements exhibit weak antiferromagnetic coupling interaction. 展开更多
关键词 2-hydroxy-5-(3' 5'-terephthalic acid)pyridine 1 4-bis(1-imdazoly)benzene NICKEL topology magnetic property
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Structure and Photoluminescence of a 3D Coordination Polymer from Triazole and 2,6-Dimethylpyridine-3,5-dicarboxylic Acid
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作者 焦晓燕 黄坤林 +1 位作者 张明星 陈新 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第7期1063-1068,共6页
A new metal-organic coordination polymer [Zn2(trz)2(mpda)(H2O)]n(1, trz = 1,2,4-triazole, H2 mpda = 2,6-dimethylpyridine-3,5-dicarboxylic acid) was synthesized and characterized by single-crystal X-ray analyse... A new metal-organic coordination polymer [Zn2(trz)2(mpda)(H2O)]n(1, trz = 1,2,4-triazole, H2 mpda = 2,6-dimethylpyridine-3,5-dicarboxylic acid) was synthesized and characterized by single-crystal X-ray analyses. The crystal is of monoclinic system, space group P21/n, a = 9.619(3), b = 8.920(3), c = 22.159(6), β = 96.897(4)°, V = 1887.3(9)3, Z = 4, Mr = 478.04, D3 c = 1.682 Mg/m, F(000) = 960, the final R = 0.0264 and wR = 0.0870(I 2σ(I)). Compound 1 consists of {[Zn4(trz)4]4+}n layers, which are further connected by mpda2- to complete a three-dimensional structure. The title compound exhibits luminescence at λmax = 415 nm upon excitation at 364 nm. 展开更多
关键词 crystal structure PHOTOLUMINESCENCE POLYMER 2 6-dimethylpyridine-3 5-dicarboxylic acid
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Oleanolic acid inhibits colon cancer cell stemness and reverses chemoresistance by suppressing JAK2/STAT3 signaling pathway
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作者 RUOYU CHEN YIMAN WU +3 位作者 FENG WANG JUNTAO ZHOU HUAZHANG ZHUANG WEI LI 《BIOCELL》 SCIE 2024年第7期1037-1046,共10页
Background:Oleanolic acid(OA),a pentacyclic triterpenoid exhibiting specific anti-cancer properties and highly effective antioxidant activity,was isolated from traditional Chinese medicinal herbs.Conversely,the OA that... Background:Oleanolic acid(OA),a pentacyclic triterpenoid exhibiting specific anti-cancer properties and highly effective antioxidant activity,was isolated from traditional Chinese medicinal herbs.Conversely,the OA that impacts colon cancer(CC)cells and its underlying mechanisms remain poorly understood.Methods:The cytotoxic effect of OA alone or OA-5-Fluorouracil(5-FU)combination on normal and CC cells was analyzed by methyl thiazolyl diphenyl-tetrazolium bromide(MTT).Then,the impact of OA on CC cell lines(LoVo and HT-29)proliferation and stemness were measured using colon formation and tumorsphere formation assays.Octamer-binding transcription factor 4(Oct4),Prominin-1(CD133),Nanog,and transcription factor SOX-2(SOX2)are cell stemness-related indicators whose expression was assessed usingfluorescence qPCR assay,Western blotting,and immunohistochemistry.The effect of OA on the proliferative potency of CC cells was evaluated using an in vivo model.Results:The stem-like characteristics and clone production of colon cancer cells were markedly reduced by OA alone or in combination with OA-5-FU.Moreover,OA increases the susceptibility of CC cells to 5-FU by blocking the cell stemness-related markers(CD133,Nanog,SOX2,and Oct4)expression levels both in vitro and in vivo,as well as by inactivating the activator of transcription 3(STAT3 signaling)and Janus kinase 2/signal transducer(JAK2).Conclusion:Thesefindings imply that oleanolic acid,both in vitro and in vivo,suppresses the JAK2/STAT3 pathway,which in turn reverses chemoresistance and decreases colon cancer cell stemness.Therefore,by reducing the recommended amount of 5-FU,this strategy may improve chemotherapeutic effectiveness and minimize undesired side effects. 展开更多
关键词 Colon cancer Oleanolic acid Stemness 5-FU JAK2/STAT3 signaling pathway
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Synthesis and Characterization of Novel Copolymers Based on 3(S)-Methyl-Morpholine-2,5-Dione
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作者 冯亚凯 陈程斌 +2 位作者 张利 田鸿 袁文婕 《Transactions of Tianjin University》 EI CAS 2012年第5期315-319,共5页
A series of novel copolymers were successfully synthesized by ring-opening polymerization (ROP) of 3 (S)-methyl-morpholine-2,5-dione (MMD) and 5-methyl-5-benzyloxycarbonyl-1,3-dioxan-2-one (MBC) using stan- no... A series of novel copolymers were successfully synthesized by ring-opening polymerization (ROP) of 3 (S)-methyl-morpholine-2,5-dione (MMD) and 5-methyl-5-benzyloxycarbonyl-1,3-dioxan-2-one (MBC) using stan- nous octoate as catalyst. The copolymers were characterized by means of ~H-NMR and FT-IR spectroscopy. Gel permeation chromatography (GPC) test shows that the average-number relative molecular mass and average-weight rela- tive molecular mass slightly increase with the increase of MBC content in feed. The results of differential scanning calorimetry (DSC) demonstrate that the glass transition temperature of copolymers increases with the increase of MBC content in copolymers. The copolymers of MMD and MBC are amorphous copolymers, as indicated by DSC results, while the homopolymer of MMD is semicrystalline. 展开更多
关键词 amino acid 3 (S)-methyl-morpholine-2 5-dione 5-methyl-5-benzyloxycarbonyl-l 3-dioxan-2-one ring- opening polymerization copolymer biomaterial
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Biodegradable Radiopaque Composite Filaments Based on Poly(p-dioxanone)and 2,3,5-triiodobenzoic Acid
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作者 徐海燕 赵帆 +2 位作者 孙晶 王富军 王璐 《Journal of Donghua University(English Edition)》 EI CAS 2017年第6期741-745,共5页
To determine the possibility of blending 2, 3, 5-triiodobenzoic acid( TIBA) and poly( p-dioxanone)( PPDO) to produce X-ray visible PPDO filaments,melt-blended PPDO with different concentrations of TIBA was obtained. S... To determine the possibility of blending 2, 3, 5-triiodobenzoic acid( TIBA) and poly( p-dioxanone)( PPDO) to produce X-ray visible PPDO filaments,melt-blended PPDO with different concentrations of TIBA was obtained. Several radiopaque filaments of PPDO polymer filled with radiopaque TIBA particles were prepared via melt-blending. Material properties of the composite filaments were investigated using various material characterization techniques,including scanning electron microscope( SEM),thermogravimetric analysis( TGA),X-ray Diffraction( XRD),dynamic rheometry and micro-CT scan. In this article,the dispersion of TIBA in PPDO,the properties of the filament,and the ratio of PPDO and TIBA and the corresponding X-ray visibility in vivo were studied. SEM results showed the dispersion of the contrast imaging agent TIBA was relatively even in the PPDO polymer. Xray analysis in vitro confirmed the enhanced radiopacity of the filaments with respect to the pure PPDO filament. The presence of iodine element in the composite filament could allow the bioabsorbable material to be monitored in vivo, and made it potential to be used in biomedical applications. 展开更多
关键词 poly(p-dioxanone)(PPDO) 2 3 5-triiodobenzoic acid(TIBA) melt-blending radiopaque filament
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Pig Liver Esterase-catalyzed Hydrolysis of Three Diesters of meso-Bicyclic Dicarboxylic Acid and Three Tetraesters of Tetrahydrofuran -2,3,4,5-tetracarboxylic Acid
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作者 MA Guang-En and Tamm Ch. (National Institutes of Pharmaceutical Research & Development, Beijing 102206, P. R. China Institut fur Organishe Chemie der Universitat Basel, CH-4056 Basel Switzerland) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2000年第4期369-374,共6页
Three diesters of exo- syn-meso-oxabicyclo (2, 2, 1 ) -hept- 5- ene- 2, 3- dicarboxylic acid and three tetraesters of tetrahydrofuran-2, 3, 4, 5-tetracarboxylic acid were synthesized and tested with enantioselective h... Three diesters of exo- syn-meso-oxabicyclo (2, 2, 1 ) -hept- 5- ene- 2, 3- dicarboxylic acid and three tetraesters of tetrahydrofuran-2, 3, 4, 5-tetracarboxylic acid were synthesized and tested with enantioselective hydrolysis catalyzed by pig liver esterase(PLE). The results of the PLEcatalyzed hydrolysis were discussed. 展开更多
关键词 Oxabicyclo(2 2 1 )-hept-5-ene-2 3-dicarboxylic acid Tetrahydrofuran-2 3 4 5- tetracarboxylic acid ESTERIFICATION Hydrolysis Pig liver esterase(PLE)
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Synthesis and Crystal Structure of Picrates of 3,5-Diamino-1,2,4-triazole 被引量:1
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作者 赵鹏 任莹辉 +4 位作者 李丹 赵风起 仪建华 宋纪蓉 马海霞 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第6期957-961,共5页
The title compound C2N5H6+C6N3O7H2-was synthesized by the reaction of 3,5-diamino-1,2,4-triazole and picric acid in the mixture of ethanol and water solution.Single crystals suitable for X-ray measurement were obtain... The title compound C2N5H6+C6N3O7H2-was synthesized by the reaction of 3,5-diamino-1,2,4-triazole and picric acid in the mixture of ethanol and water solution.Single crystals suitable for X-ray measurement were obtained at room temperature.The structure was characterized by elemental analysis and IR and determined by X-ray diffraction analysis.Crystallographic data:C8N8H8O7,Mr = 328.22,monoclinic,space group C2/c with a = 22.815(2),b = 4.8086(5),c = 22.564(2),β = 93.976(2)°,V = 2469.6(4)3,Dc = 1.766 g/cm3,Z = 8,μ = 0.156 mm-1,F(000) = 1344,the final R= 0.0309,wR= 0.0864. 展开更多
关键词 picric acid(PA) 3 5-diamino-1 2 4-triazole(DAT) synthesis X-ray diffraction
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Hydrothermal Syntheses and Crystal Structures of Six Complexes Constructed from 1,3,5-Benzenetricarboxylic Acid and 4'-(4-Pyridyl)-2,2':6',2''-terpyridine Mixed Ligands 被引量:4
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作者 乔宇 王炫博 +4 位作者 周艳凤 刘力辉 车广波 刘春波 刘晓腾 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第8期1381-1394,共14页
Six new transition metal complexes, [Zn(HBTC)(PYTPY)]n·n PYTPY(1), [Cu(HBTC)(PYTPY)]n·n PYTPY(2), [Co(HBTC)(PYTPY)]n·n DMF(3), [Mn(HBTC)(PYTPY)]n·n DMF(4), [Cd(HBTC)(PYTP... Six new transition metal complexes, [Zn(HBTC)(PYTPY)]n·n PYTPY(1), [Cu(HBTC)(PYTPY)]n·n PYTPY(2), [Co(HBTC)(PYTPY)]n·n DMF(3), [Mn(HBTC)(PYTPY)]n·n DMF(4), [Cd(HBTC)(PYTPY)(H2O)]n·2nH2O(5), and [Co(HBTC)(PYTPY)(H2O)2](6),(H3BTC = 1,3,5-benzenetricarboxylic acid, PYTPY = 4'-(4-pyridyl)-2,2':6',2''-terpyridine, DMF = N,N?-dimethylformamide), have been synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. Complexes 1~5 all feature one-dimensional chain structures, and complex 6 exhibits a zero-dimensional structure. Complexes 1~5 present three-dimensional(3D) supramolecular frameworks via π-π stacking interactions, whenas 6 has also a 3D supramolecular structure assembled by hydrogen bonding. Meanwhile, complexes 1 ~ 6 exhibit the thermal stabilities and photoluminescent properties. 展开更多
关键词 transition metal complex 1 3 5-benzenetricarboxylic acid 4'-(4-pyridyl)-2 2' 6' 2''-terpyridine 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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氨基酸辅助增强Cs_(3)Cu_(2)I_(5)钙钛矿荧光粉及其蓝光LED的性能研究 被引量:1
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作者 许泽尧 熊浩 +3 位作者 李平 洪锦泉 杨爱军 江琳沁 《人工晶体学报》 CAS 北大核心 2023年第9期1681-1690,共10页
本文采用简单的室温球磨法制备了一系列L-组氨酸(L-His)和5-氨基戊酸(5-Ava)修饰的Cs_(3)Cu_(2)I_(5)钙钛矿荧光粉,并对Cs_(3)Cu_(2)I_(5)∶x%L-His和Cs_(3)Cu_(2)I_(5)∶x%5-Ava(x=0、0.5、1、1.5、2)样品的物相、形貌、光学和稳定性... 本文采用简单的室温球磨法制备了一系列L-组氨酸(L-His)和5-氨基戊酸(5-Ava)修饰的Cs_(3)Cu_(2)I_(5)钙钛矿荧光粉,并对Cs_(3)Cu_(2)I_(5)∶x%L-His和Cs_(3)Cu_(2)I_(5)∶x%5-Ava(x=0、0.5、1、1.5、2)样品的物相、形貌、光学和稳定性进行了分析。氨基酸添加未对Cs_(3)Cu_(2)I_(5)钙钛矿的晶体结构造成影响,Cs_(3)Cu_(2)I_(5)仍属于Pnma空间群,但氨基酸的加入对钙钛矿的晶粒尺寸有一定的限制作用,并有效改善了其光电性能。当x=1时,经L-His和5-Ava修饰的Cs_(3)Cu_(2)I_(5)钙钛矿较纯Cs_(3)Cu_(2)I_(5)钙钛矿的荧光强度分别提升约1.30倍和1.41倍,光致发光量子产率(PLQY)提高约25.09个百分点和30.47个百分点,荧光寿命有效延长。研究发现,性能的改善与氨基酸中氨基以及羧基基团的作用有关,氨基以及羧基基团钝化了钙钛矿的缺陷并抑制非辐射复合过程的能量损失。此外,采用L-His和5-Ava修饰的Cs_(3)Cu_(2)I_(5)钙钛矿荧光粉制备了蓝光发光二极管(LED),在70 mA的偏流下,该LED光效率较纯Cs_(3)Cu_(2)I_(5)器件分别增强达1.85倍和2.10倍,表明这类材料在LED领域有着极大的应用价值。 展开更多
关键词 钙钛矿荧光粉 Cs_(3)Cu_(2)I_(5) 氨基酸修饰 光致发光量子产率 缺陷 非辐射复合
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Superior resistance to alkali metal potassium of vanadium-based NH_(3)-SCR catalyst promoted by the solid superacid SO_(4)^(2-)-TiO_(2) 被引量:4
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作者 Yaoyao Peng Lei Song +6 位作者 Siru Lu Ziyu Su Kui Ma Siyang Tang Shan Zhong Hairong Yue Bin Liang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第3期246-256,共11页
The significant decrease of acid sites caused by alkali metal poisoning is the major factor in the deactivation of commercial V_(2)O_(5)-WO_(3)/TiO_(2)NH_(3)-SCR catalysts.In this work,the solid superacid SO_(4)^(2-)-... The significant decrease of acid sites caused by alkali metal poisoning is the major factor in the deactivation of commercial V_(2)O_(5)-WO_(3)/TiO_(2)NH_(3)-SCR catalysts.In this work,the solid superacid SO_(4)^(2-)-TiO_(2) modified by sulfate radicals,was selected as the catalyst support,which showed superior potassium resistance.The physicochemical properties and K-poisoning resistance of the V_(2)O_(5)-WO_(3)/SO_(4)^(2-)-TiO_(2)(VWSTi) catalyst were carried out by XRD,BET,H2-TPR,NH3-TPD,XPS,in situ DRIFTS and TG.The results pointed out that the introduction of SO_(4)^(2-)significantly increased the NH3-SCR catalytic activity at high temperatures,with an exceptionally high NO_(x) conversion over 90% between 275℃ and 500℃.When 0.5%(mass) K_(2)O was doped on the catalysts,the catalytic performance of the traditional V_(2)O_(5)-WO_(3)/TiO_(2)(VWTi) catalyst decreased significantly,while the VWSTi catalyst could still maintain a NOxconversion over 90%in the range of 300–500℃.The characterizations suggested that the support of SO_(4)^(2-)-TiO_(2) greatly increased the number of acidic sites,thereby enhancing the adsorption capacity of the reactant NH_(3).The results above demonstrated a potential approach to achieve superior potassium resistance for NH3-SCR catalysts using solid superacid. 展开更多
关键词 Selective catalytic reduction(NH_(3)-SCR) V_(2)O_(5)-WO_(3)/TiO_(2) Solid superacid Anti-poisoning acidITY
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2-[(2-乙基-5-氟苯并呋喃-3-基)甲基]-4-甲基-5-噻唑甲酸合成路线的改进
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作者 谢珺 崔杏 +1 位作者 王建塔 汤磊 《化学与生物工程》 CAS 2023年第7期30-33,共4页
在课题组前期2-[(2-乙基-5-氟苯并呋喃-3-基)甲基]-4-甲基-5-噻唑甲酸合成路线的基础上进行改进,以5-氟水杨醛为起始原料,经环合、还原、亲电取代、硫代、环合、水解反应得到目标化合物,化合物结构经^(1)HNMR、^(13)CNMR和HRMS确证。与... 在课题组前期2-[(2-乙基-5-氟苯并呋喃-3-基)甲基]-4-甲基-5-噻唑甲酸合成路线的基础上进行改进,以5-氟水杨醛为起始原料,经环合、还原、亲电取代、硫代、环合、水解反应得到目标化合物,化合物结构经^(1)HNMR、^(13)CNMR和HRMS确证。与原合成路线相比,该路线减少了合成步骤,目标化合物总收率由0.3%提高到5.0%。 展开更多
关键词 黄嘌呤氧化酶 2-[(2-乙基-5-氟苯并呋喃-3-基)甲基]-4-甲基-5-噻唑甲酸 合成 改进
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乳酸-3-苯甲基-2,5-吗啉二酮共聚物的合成及共聚物组分分析 被引量:2
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作者 刘迎 魏荣卿 刘晓宁 《高分子学报》 SCIE CAS CSCD 北大核心 2009年第1期66-71,共6页
以苯丙氨酸为原料合成3-苯甲基-2,5-吗啉二酮(PMD),以辛酸亚锡为催化剂,研究PMD与丙交酯(LA)开环共聚得到乳酸-3-苯甲基-2,5-吗啉二酮共聚物,用IR、1H-NMR、DSC对共聚物进行分析表征,表明可得到含有苯丙氨酸的聚乳酸共聚物.利用红外定... 以苯丙氨酸为原料合成3-苯甲基-2,5-吗啉二酮(PMD),以辛酸亚锡为催化剂,研究PMD与丙交酯(LA)开环共聚得到乳酸-3-苯甲基-2,5-吗啉二酮共聚物,用IR、1H-NMR、DSC对共聚物进行分析表征,表明可得到含有苯丙氨酸的聚乳酸共聚物.利用红外定量分析法替代1H-NMR法测定共聚物中PMD的组分含量,以1671.53cm-1和870.82cm-1两波数处特征峰的吸光度比值,作标准工作曲线Y=0.05567X+0.1091,r=0.9993.比较了催化剂浓度、反应时间、温度对共聚物组分含量、共聚物特性黏数[η]的影响.结果表明,低催化剂浓度条件下(0.025mol%与0.1mol%),产物特性黏数[η]随反应时间的延长先增加然后下降;而在高催化剂浓度(0.2mol%)的条件下,因主链中形成了更多更稳定的酰胺键,产物特性黏数[η]10h内维持不变;随PMD加入量的增多,进入共聚物中的PMD组分也相应地呈线性增加,但因PMD的开环活性低于丙交酯,所以苯丙氨酸引入聚乳酸链段中比较困难,但在低投料比条件下(<20mol%),升高反应温度有利于PMD含量的增加;同样也因为PMD在共聚物中组分含量的增多,苯环的稳定性使共聚物[η]受催化剂浓度及温度的影响逐渐减弱. 展开更多
关键词 丙交酯 3-苯甲基-2 5-吗啉二酮 乳酸-3-苯甲基-2 5-吗啉二酮共聚物 红外定量 共聚物组成分析
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Crystal Structure and Theoretical Studies of Tetrahytrate(1-H-1,2,4-triazole-3,5-dicarboxylicacid)nickel 被引量:2
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作者 闫娟枝 卢丽萍 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第8期1334-1340,共7页
A new compound, [Ni(Hdctrz)(H2O)4](1, H3dctrz = 1-H-1,2,4-triazole-3,5-dicarboxylic acid), has been successfully synthesized via slow evaporation. The structure of 1 was characterized by FT-IR, elemental analysi... A new compound, [Ni(Hdctrz)(H2O)4](1, H3dctrz = 1-H-1,2,4-triazole-3,5-dicarboxylic acid), has been successfully synthesized via slow evaporation. The structure of 1 was characterized by FT-IR, elemental analysis and single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic, space group P21/c with a = 6.871(1), b = 11.468(1), c = 12.178(1) A, b = 101.291(1)o, V = 941.01(16) A3, Z = 4, C4H9N3O8Ni, Mr = 285.85, Dc = 2.018 g·cm–3, m = 2.10 mm–1, F(000) = 584, GOOF = 1.025, the final R = 0.0515 and wR = 0.2125 for 1404 observed reflections(I 〉 2s(I)). The crystal structure is assembled by a slightly distorted {NiNO5} octahedral geometry and hydrogen bonds viz. N–H…O, O–H…O, C–O…π and π···π weak interactions. A rare π···π interaction from triazolate and carboxylate is affirmed through the molecular orbitals(MO) of three adjacent Ni CN molecules. The 3D Hirshfeld surface analysis was employed to gain additional insight into the interactions responsible for the packing of compound 1. Quantitative examination of 2D fingerprint plots revealed, amongst others, the dominating participation of O···H, N···H and π···π interactions in the molecular packing. 展开更多
关键词 1-H-1 2 4-triazole-3 5-dicarboxylic acid Ni compound weak interactions Hirshfeld surface
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pH Dependent Supramolecules Based on Co-crystallization of Pyrazine-2,3,5,6-tetracarboxylic Acid with 4,4'-Bipyridine through Intermolecular Hydrogen Bonds 被引量:4
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作者 梅应轩 徐峰 +1 位作者 魏振宏 蔡琥 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第7期1031-1037,共7页
Co-crystallization of pztcH_4 with 4,4'-bipyridine(4,4'-bipy) in pH = 3-4 and 1-2 gave two new binary molecular adducts: [(4,4'-bipy H2)(pztc H2)](1) and [(4,4'-bipy H2)(pztcH3)(Cl)]·4H2O(2),... Co-crystallization of pztcH_4 with 4,4'-bipyridine(4,4'-bipy) in pH = 3-4 and 1-2 gave two new binary molecular adducts: [(4,4'-bipy H2)(pztc H2)](1) and [(4,4'-bipy H2)(pztcH3)(Cl)]·4H2O(2), respectively. Compounds 1 and 2 have been characterized by IR, elemental analysis, NMR and X-ray single-crystal diffraction. Compound 1 crystallizes in triclinic, space group P1 with a = 5.7752(12), b = 7.9126(16), c = 9.4492(19) ?, α = 97.49(3), β = 107.71(3), γ = 94.52(3)o, V = 404.62(14) A^3, Z = 1, μ = 0.137 mm^1, Dc = 1.692 Mg/m^3, C18H12N4O8, Mr = 412.32, F(000) = 212, S = 1.025, R = 0.0360 and wR = 0.0973. Compound 2 crystallizes in monoclinic, space group C2/c with a = 17.093(3), b = 7.7665(16), c = 18.414(4) A, β = 113.36(3)o, V = 2244.1(8) A^3, Z = 4, μ = 0.244 mm^-1, Dc = 1.542 Mg/m^3, C18H21ClN4O12, Mr = 520.84, F(000) = 1080, S = 1.021, R = 0.0343 and wR = 0.0978. In compound 1, pztc H22- anions self-formed 2-D sheets by strong Oacid-H···Oacidhydrogen bonds, which are further extended to form a 3-D supramolecular network bridged with 4,4?-bipy via N-H···Oacid interactions. In compound 2, besides the 1-D chain constructed by pztc H3-itself through strong H-bond Oacid-H···Oacid, the other chain is constructed with 4,4?-bipy H22+, Cl-anion and water molecules by moderate H-bonds and Ow-H···Cl and N-H···Ow. The two chains are linked with μ3-connected water molecules resulting from the combination of strong synthon-assisted H-bonding Oacid-H···Ow to afford an interlaced 3-D network. 展开更多
关键词 pyrazine-2 3 5 6-tetracarboxylic acid 4 4'-bipyridine hydrogen bond
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2-甲基-3,5-吡啶二甲酸的制备及其结构表征 被引量:2
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作者 贾洪斌 王雅珍 +3 位作者 刘英 赵德建 匡华 张继振 《江苏技术师范学院学报》 2005年第4期56-58,共3页
多羧酸类化合物在配位聚合物的合成中是很有价值的配体之一。本文通过高锰酸钾氧化法意外地制备了2-甲基-3,5-吡啶二甲酸,它具有很好的三角形对称结构,是理想的配位体。对它的结构进行了红外和核磁共振结构表征,结果与目标结构能够较好... 多羧酸类化合物在配位聚合物的合成中是很有价值的配体之一。本文通过高锰酸钾氧化法意外地制备了2-甲基-3,5-吡啶二甲酸,它具有很好的三角形对称结构,是理想的配位体。对它的结构进行了红外和核磁共振结构表征,结果与目标结构能够较好地吻合。 展开更多
关键词 2-甲基-3 5-吡啶二甲酸 2 3 5-三甲基吡啶 氧化
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2′-脱氧腺苷-5′-N-[(2S)-2-(3-苯甲酰苯基)-1-氧代丙基]甘氨酸酯的合成
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作者 何小飞 沈振陆 +2 位作者 郑旭明 胡信全 莫卫民 《化学试剂》 CAS CSCD 北大核心 2010年第9期783-786,共4页
以N-[(2S)-2-(3-苯甲酰苯基)-1-氧代丙基]甘氨酸和2′-脱氧腺苷为原料合成了标题化合物。产物结构经IR、1HNMR、13CNMR和MS确证。实验结果表明,2-(7-偶氮苯并三氮唑)-N,N,N′,N′-四甲基脲六氟磷酸酯(HATU)在该反应中是一种较好的缩合... 以N-[(2S)-2-(3-苯甲酰苯基)-1-氧代丙基]甘氨酸和2′-脱氧腺苷为原料合成了标题化合物。产物结构经IR、1HNMR、13CNMR和MS确证。实验结果表明,2-(7-偶氮苯并三氮唑)-N,N,N′,N′-四甲基脲六氟磷酸酯(HATU)在该反应中是一种较好的缩合试剂。此外发现,N-[(2S)-2-(3-苯甲酰苯基)-1-氧代丙基]甘氨酸乙酯在皂化反应中会消旋。 展开更多
关键词 2′-脱氧腺苷-5′-N-[(2S)-2-(3-苯甲酰苯基)-1-氧代丙基]甘氨酸酯 N-[(2S)-2-(3-苯甲酰苯基)-1-氧代丙基]甘氨酸 2′-脱氧腺苷
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5%ZnO-3%MgO/SiO_2催化2-乙基己醇直接合成2-乙基己酸 被引量:1
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作者 严宏贵 章毅 《广州化工》 CAS 2012年第15期122-123,138,共3页
采用等体积浸渍法制备了5%ZnO-3%MgO/SiO2催化剂,以纯氧为氧化剂,在常压下催化氧化2-乙基己醇直接合成2-乙基己酸,对该合成的催化剂用量、氧气流量、反应温度、反应时间等工艺条件进行了优化,确定了最佳工艺条件。结果表明,该合成的最... 采用等体积浸渍法制备了5%ZnO-3%MgO/SiO2催化剂,以纯氧为氧化剂,在常压下催化氧化2-乙基己醇直接合成2-乙基己酸,对该合成的催化剂用量、氧气流量、反应温度、反应时间等工艺条件进行了优化,确定了最佳工艺条件。结果表明,该合成的最佳工艺条件为:2-乙基己醇50 mL,催化剂用量2.5 g,氧气流量30 mL/min,反应温度125℃,反应时间9 h,在此最佳工艺条件下,2-乙基己醇转化率达63.6%,2-乙基己酸选择性可达75.4%。 展开更多
关键词 2-乙基己醇 2-乙基己酸 5%ZnO-3%MgO/SiO2 纯氧
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Syntheses,Crystal Structures and Properties of Co(Ⅱ) and Cu(Ⅱ) Complexes with 5-Nitro-1,2,3-benzenetricarboxylic Acid
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作者 候红卫 李秀芹 +1 位作者 马录芳 王利亚 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第12期1841-1847,共7页
Two new coordination polymers,{[Co(O2N-Hbtb)(phen)(H2O)3]·2H2O}n 1 and {[Cu3(O2N-btb)2(bipy)2(H2O)4]·4H2O}n 2(O2N-H3btb=5-nitro-1,2,3-benzenetricarboxylic acid,phen=1,10-phenanthroline,bipy=2,2... Two new coordination polymers,{[Co(O2N-Hbtb)(phen)(H2O)3]·2H2O}n 1 and {[Cu3(O2N-btb)2(bipy)2(H2O)4]·4H2O}n 2(O2N-H3btb=5-nitro-1,2,3-benzenetricarboxylic acid,phen=1,10-phenanthroline,bipy=2,2'-bipyridine),were prepared through hydrothermal reactions of Co(Ⅱ) or Cu(Ⅱ) salt with O2N-H3btb in the presence of different auxiliary N-donor ligands.Their crystal structures were determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis and IR spectroscopy.In the two complexes,O2N-H3btb ligand acts as monodentate and bis-monodentate modes,respectively.Complex 1 displays a two-dimensional layered structure through the inter-and intramolecular hydrogen bonding interactions while complex 2 has an O2N-btb bridged one-dimensional chain which is extended into a three-dimensional network by hydrogen bonding interactions.The magnetic properties of complex 2 are investigated over the temperature range of 2~300 K and ferromagnetic interactions are observed. 展开更多
关键词 5-nitro-1 2 3-benzenetricarboxylic acid hydrothermal synthesis crystal structure magnetic properties
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6-(4-苯磺酰基-3-甲基-2-丁烯)-基-2,3-二甲氧基-5-甲基氢醌双苄醚的合成
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作者 陈田 杨运泉 +2 位作者 刘文英 王威燕 周国平 《化工进展》 EI CAS CSCD 北大核心 2008年第5期745-748,752,共5页
以异戊二烯为原料,经与苯磺酰氯加成、水解乙酰化、皂化3步反应,制得末端羟基取代的异戊二烯短侧链——(E)-1-苯磺酰基-2-甲基-4-羟基-2-丁烯(简称产物A),并用乙酸乙酯-乙醚混合溶剂对产物A进行提纯精制。以还原型辅酶Q0(氢醌)为母环,... 以异戊二烯为原料,经与苯磺酰氯加成、水解乙酰化、皂化3步反应,制得末端羟基取代的异戊二烯短侧链——(E)-1-苯磺酰基-2-甲基-4-羟基-2-丁烯(简称产物A),并用乙酸乙酯-乙醚混合溶剂对产物A进行提纯精制。以还原型辅酶Q0(氢醌)为母环,杂多酸为催化剂,与产物A进行偶联反应,然后采用溴化苄对母环羟基进行保护,用乙醚-异丙醚的混合溶剂进行提纯精制,选择性结晶得到了侧链延长法合成辅酶Q10的关键中间体辅酶Q1前体,即6-(4-苯磺酰基-3-甲基-2-丁烯)-基-2,3-二甲氧基-5-甲基氢醌双苄醚(简称产物B)。探讨了各主要影响因素对合成反应过程及结果的影响,目标产物B收率达75%(以产物A为基准)。产物A与目标产物B经测熔点、1H NMR分析和FTIR分析鉴定,确证其为(E)-异构体。 展开更多
关键词 6-(4-苯磺酰基-3-甲基-2-丁烯)-基-2 3-二甲氧基-5-甲基氢醌双苄醚 (E)-1-苯磺酰基-2-甲基-4-羟基-2-丁烯
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