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6-氟-4-羟基-3-氧代-3,4-二氢喹喔啉-1(2 H)-羧酸叔丁酯的合成、晶体结构及抗肿瘤活性研究
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作者 毛云虹 赵春深 《人工晶体学报》 CAS 北大核心 2024年第7期1257-1268,共12页
喹喔啉类化合物由于具有显著的生物活性而被广泛应用于医药、化工领域,特别是抗癌药物研发领域。本文通过四步反应法首次合成了6-氟-4-羟基-3-氧代-3,4-二氢喹喔啉-1(2 H)-羧酸叔丁酯,经溶液结晶法获得其单晶体。晶体学分析表明,该化合... 喹喔啉类化合物由于具有显著的生物活性而被广泛应用于医药、化工领域,特别是抗癌药物研发领域。本文通过四步反应法首次合成了6-氟-4-羟基-3-氧代-3,4-二氢喹喔啉-1(2 H)-羧酸叔丁酯,经溶液结晶法获得其单晶体。晶体学分析表明,该化合物属单斜晶系,空间群C2/c,晶胞常数a=1.28663(10)nm,b=2.25249(17)nm,c=1.01564(7)nm,Z=8,ρ_(c)=1.359 g·cm^(-3),R=0.0538,R_(w)=0.1406。在B3LYP/6-311+G(2d,p)模式下使用密度泛函理论(DFT)计算了该化合物的最佳结构,与X射线单晶衍射确定的晶体结构基本一致。抗肿瘤活性研究表明其有良好的抗肿瘤作用。此外,通过DFT计算了分子的静电势和前沿分子轨道。 展开更多
关键词 喹喔啉类化合物 6-氟-4-羟基-3-氧代-3 4-二氢喹喔啉-1(2 H)-羧酸叔丁酯 晶体结构 密度泛函理论 合成 抗肿瘤活性
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大豆油制生物柴油固体酸Zr(SO_(4))2/Al_(2)O_(3)催化剂的制备与表征
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作者 黄振旭 陈梦瑶 +2 位作者 高海荣 许梦娟 段莹莹 《山东化工》 CAS 2024年第8期79-82,共4页
采用浸渍法制备了固体酸催化剂Zr(SO_(4))_(2)/Al_(2)O_(3),考察了催化剂的制备条件和酯化反应条件对生物柴油产率的影响,并采用X射线衍射(XRD)、扫描电镜(SEM)和比表面积(BET)和热重分析(TG-DTA)等手段对催化剂进行了表征。结果表明,... 采用浸渍法制备了固体酸催化剂Zr(SO_(4))_(2)/Al_(2)O_(3),考察了催化剂的制备条件和酯化反应条件对生物柴油产率的影响,并采用X射线衍射(XRD)、扫描电镜(SEM)和比表面积(BET)和热重分析(TG-DTA)等手段对催化剂进行了表征。结果表明,活性组分均匀分散在载体的表面,催化剂表现出较高的催化活性;在Zr(SO_(4))_(2)的负载量(占催化剂的质量)为30%、焙烧温度为350℃,(甲)醇(大豆)油物质的量比为9∶1、催化剂用量为大豆油质量的4%时,生物柴油的产率最高为92.40%,且催化剂循环使用6次后,生物柴油的产率仍保持在90%以上。 展开更多
关键词 生物柴油 固体酸 硫酸锆 氧化铝 大豆油
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聚甲基丙烯酸对STI CMP中SiO_(2)和Si_(3)N_(4)去除速率选择比的影响
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作者 李相辉 张祥龙 +3 位作者 孟妮 聂申奥 邱宇轩 何彦刚 《半导体技术》 北大核心 2024年第2期131-137,共7页
在浅沟槽隔离(STI)化学机械抛光(CMP)中,需要保证极低的Si_(3)N_(4)去除速率,以及相对较高的SiO_(2)去除速率,并且要达到SiO_(2)与Si_(3)N_(4)的去除速率选择比大于30的要求。在CeO_(2)磨料质量分数为0.25%,抛光液pH=4的前提下,研究了... 在浅沟槽隔离(STI)化学机械抛光(CMP)中,需要保证极低的Si_(3)N_(4)去除速率,以及相对较高的SiO_(2)去除速率,并且要达到SiO_(2)与Si_(3)N_(4)的去除速率选择比大于30的要求。在CeO_(2)磨料质量分数为0.25%,抛光液pH=4的前提下,研究了聚甲基丙烯酸(PMAA)对SiO_(2)与Si_(3)N_(4)去除速率以及二者去除速率选择比的影响,分析了PMAA在影响SiO_(2)与Si_(3)N_(4)去除速率过程中的作用机理。结果表明,PMAA的加入可以降低SiO_(2)与Si_(3)N_(4)的去除速率,当PMAA的质量分数为120×10^(-6)时,SiO_(2)和Si_(3)N_(4)的去除速率分别为185.4 nm/min和3.0 nm/min,去除速率选择比为61。抛光后SiO_(2)与Si_(3)N_(4)晶圆表面有较好的表面粗糙度,分别为0.290 nm和0.233 nm。 展开更多
关键词 浅沟槽隔离(STI) 化学机械抛光(CMP) 二氧化硅(SiO_(2)) 氮化硅(Si_(3)N_(4)) 聚甲基丙烯酸(PMAA) 去除速率选择比
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Synthesis and Crystal Structure of α-(3-Phenylureido)-α-(2,4-Dichlorophenyl) Methyl Phenylphosphinic Acid
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作者 ZHOU Jia CHEN Ru-Yu(Institute of Elemento-Organic Chemistry, National Key Laboratory ofElemento-Organic Chemistry, Nankai University, Tainjin 300071)WANG Hong-Gen YAO Xin-Kan(Central Laboratory, Nankai University, Tianjin 300071) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1997年第3期207-210,共4页
The crystal structure of a (3-phenylureido)-a (2, 4-dichlorophenyl)methyl phenylphosphinic acid, C20H17Cl2N2O3P, Mr= 435. 25,which was obtained bydesulphurisation of cis-3, 4-dipheny1-5- (2, 4-dichlorophenyl ) -1, 3, ... The crystal structure of a (3-phenylureido)-a (2, 4-dichlorophenyl)methyl phenylphosphinic acid, C20H17Cl2N2O3P, Mr= 435. 25,which was obtained bydesulphurisation of cis-3, 4-dipheny1-5- (2, 4-dichlorophenyl ) -1, 3, 4-diazaphospholidin2-thione-4-oxide utilizing Ag+ -H2O system in a yield of 89%, is reported. It crystallizes in orthorhombic space group Pca21 with a= 11. 286(2), b= 20. 601 (4) f c=8. 695(2)A, V= 2021 (1) A3, Z= 4, D.= 1. 430 g/cm3, p=4. 21 cm-1, F(000) =896.The final R factor is 0. 040 and Rw is 0. 045 for 946 unique observed reflections[I>3a(I)]. The result of X-ray analysis indicates that the molecules in the crystal are linkedtogether by the O(3 ) ...H (2d) - N (2d ) intermolecular hydrogen-bondings. 展开更多
关键词 crystal structure DESULPHURISATION reaction 1 3 4-diazaphospholidin-2-thione phosphinic acid derivative
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K_(2)FeO_(4)-FeCl_(3)联合强化剩余污泥厌氧消化产酸
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作者 田梦佳 刘锋 +3 位作者 李祥 马军 王加恩 赵魏东 《中国环境科学》 EI CAS CSCD 北大核心 2023年第8期4089-4098,共10页
通过碱性高铁酸钾(K_(2)FeO_(4))-FeCl_(3)预处理联合厌氧消化对剩余污泥进行减量化处理,探讨不同形态的铁源及不同铁浓度对以有机酸回收为目标的污泥减量化过程的影响,并寻找最适铁投加量.结果表明在预处理过程中碱性K_(2)FeO_(4)对污... 通过碱性高铁酸钾(K_(2)FeO_(4))-FeCl_(3)预处理联合厌氧消化对剩余污泥进行减量化处理,探讨不同形态的铁源及不同铁浓度对以有机酸回收为目标的污泥减量化过程的影响,并寻找最适铁投加量.结果表明在预处理过程中碱性K_(2)FeO_(4)对污泥聚集体结构破坏起着重要作用.与空白相比,挥发性悬浮物固体(VSS)下降了26.79%,中值粒径(Dx(50))下降了90%,污泥沉降比(SV_(30))下降了33%,污泥沉降性能变好,减量效果明显.FeCl_(3)在预处理过程仅具有絮凝作用.在厌氧消化过程,经碱K_(2)FeO_(4)预处理后的污泥产酸量高于空白组.适量铁离子的增加可加速有机酸的产生速率.最适铁投加量20mg Fe/g VSS的K_(2)FeO_(4)及21mg Fe/g VSS的FeCl_(3)(即TFe投加量为41mg Fe/g VSS)的产酸效果最好,在消化第3d挥发性有机酸达到峰值(436.1mg COD/g VSS),是空白组峰值的4.45倍.当经过15d消化后,PO_(4)^(3-)-P去除率达69.8%,是仅投加K_(2)FeO_(4)预处理的2.03倍.此外,适量铁的投加还有利于产酸菌(Actinobacteria门和Chloroflexi门)富集,促进了厌氧消化产酸速率提升,而铁投加量高于48mg Fe/g VSS反而会抑制厌氧环境中产酸菌的活性. 展开更多
关键词 K_(2)FeO_(4) FeCl_(3) 剩余污泥 厌氧消化 挥发性脂肪酸
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硫酸负载对Pt/SO_(4)^(2-)-(ZrO_(2)-Al_(2)O_(3))催化剂性能的影响
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作者 宋宇 辛靖 +4 位作者 张海洪 曾土城 范文轩 王廷海 王鹏照 《石化技术与应用》 CAS 2023年第4期251-255,共5页
采用共沉淀-浸渍法制备了系列硫酸负载催化剂Pt/SO_(4)^(2-)-(ZrO_(2)-Al_(2)O_(3)),利用X射线衍射仪、物理吸附仪、红外光谱仪等对其进行了表征,并在固定床微型反应装置上对其催化异丁烷正构化反应性能进行了评价。结果表明:硫酸单层... 采用共沉淀-浸渍法制备了系列硫酸负载催化剂Pt/SO_(4)^(2-)-(ZrO_(2)-Al_(2)O_(3)),利用X射线衍射仪、物理吸附仪、红外光谱仪等对其进行了表征,并在固定床微型反应装置上对其催化异丁烷正构化反应性能进行了评价。结果表明:硫酸单层分散于载体表面,硫酸负载不利于四方晶相ZrO_(2)长大;随着硫酸负载量的增加,催化剂介孔结构的有序性增强且孔径减小,孔径最小降为3.41 nm,孔容可提高至0.091 cm^(3)/g,比表面积增至100 m^(2)/g以上;在反应温度为250℃的条件下,硫酸负载量为15%时,异丁烷转化率高达41.74%;硫酸负载量为2%时,正丁烷选择性最高为93.91%。 展开更多
关键词 异丁烷 正构化 催化剂 硫酸 Pt/SO_(4)^(2-)-(ZrO_(2)-Al_(2)O_(3)) 单层分散 酸性位
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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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2-甲基-3-[4,5-二氢异噁唑]-4-甲磺酰基苯甲酸液相色谱分析
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作者 单芳 王慧 +2 位作者 靳璐璐 刘盼盼 陈广赟 《山东化工》 CAS 2023年第16期147-150,153,共5页
建立了2-甲基-3-[4,5-二氢异噁唑]-4-甲磺酰基苯甲酸液相色谱分析方法,以C 18为填充物的不锈钢柱和可变波长紫外检测器,以乙腈、磷酸水溶液(pH值=3)体积比为40∶60为流动相,在270 nm波长下,采用高效液相色谱外标法,以梯度洗脱程序对试... 建立了2-甲基-3-[4,5-二氢异噁唑]-4-甲磺酰基苯甲酸液相色谱分析方法,以C 18为填充物的不锈钢柱和可变波长紫外检测器,以乙腈、磷酸水溶液(pH值=3)体积比为40∶60为流动相,在270 nm波长下,采用高效液相色谱外标法,以梯度洗脱程序对试样中的2-甲基-3-[4,5-二氢异噁唑]-4-甲磺酰基苯甲酸进行高效液相色谱分离和分析,结果表明,在试验条件下,2-甲基-3-[4,5-二氢异噁唑]-4-甲磺酰基苯甲酸的质量浓度与其相应响应值之间的线性相关系数(R^(2))为0.9999,标准偏差为0.28,变异系数为0.28%,平均回收率为98.0%,可以满足2-甲基-3-[4,5-二氢异噁唑]-4-甲磺酰基苯甲酸的定性和定量分析,结果呈现性好。 展开更多
关键词 2-甲基-3-[4 5-二氢异噁唑]-4-甲磺酰基苯甲酸 高效液相色谱法 分析
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Highly efficient synthesis of 2,3-dihydroquinazolin-4(1H)-ones catalyzed by heteropoly acids in water 被引量:6
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作者 YingXiao Zong Yan Zhao +3 位作者 WenCai Luo Xing Hai Yu Jun Ke Wang Yi Pan 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第7期778-781,共4页
Heteropoly acids efficiently catalyzed the cyclocondensation reaction of anthranilamide with aldehydes in water at ambient temperature and afforded the corresponding 2,3-dihydro-4(1H)-quinazolinones compounds in goo... Heteropoly acids efficiently catalyzed the cyclocondensation reaction of anthranilamide with aldehydes in water at ambient temperature and afforded the corresponding 2,3-dihydro-4(1H)-quinazolinones compounds in good to excellent yields.This method provides mild reaction conditions and clean reaction profiles,using a small quantity of catalyst and a simple workup procedure. 展开更多
关键词 Heteropoly acid 2 3-Dihydroquinazolin-4(1H)-ones WATER
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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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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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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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All-transRetinoic Acid Regulates Th1/Th2 Balance in CD4+T cells When GATA-3 is Deficient 被引量:6
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作者 ZHU Yan Feng HU Jia Zhe +2 位作者 ZHAO Pin Nan LIU Lin Xi and LI Yun 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第9期774-777,共4页
The essential effect of vitamin A on immune function occurs through various mechanisms including direct effect on ThloTh2 balance modulation. However, it is unclear whether or not vitamin A can regulate Thl-Th2 balanc... The essential effect of vitamin A on immune function occurs through various mechanisms including direct effect on ThloTh2 balance modulation. However, it is unclear whether or not vitamin A can regulate Thl-Th2 balance under a strong Thl-polarizing condition. Therefore, the purpose of our study was to examine the effect of vitamin A metabolite allotrans retinoic acid (ATRA) on ThloTh2 differentiation in CD4~ T cells under GATA-3 deficiency, which can induce Thl-polarizing condition. In the present study, GATA-3 deficiency T cells were induced by siRNA and checked by real-time quantitative PCR and western blot. GATA-3 deficiency CD4+ T cells and normal CD4+ T were treated for 48 h with or without ATRA. 展开更多
关键词 GATA cell Th All-transRetinoic acid Regulates Th1/Th2 Balance in CD4+T cells When GATA-3 is Deficient CD
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A One-dimensional Cd(Ⅱ)Coordination Polymer Constructed from 1,4-Benzene-dicarboxylic Acid and 3-(2,6-Di(pyrazin-2-yl)pyridin-4-yl)-1H-indole:Synthesis,Structure and Photoluminescence 被引量:2
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作者 谢玲 卢丽萍 朱苗力 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第10期1606-1614,共9页
A new coordination polymer {[Cd(C_(21)H_(14)N_6)(C_8H_4O_4)]·H_2O}_n(1) was synthesized by an elaborate design via the reaction of 3-(2,6-di(pyrazin-2-yl)pyridin-4-yl)-1H-indole(bppi),1,4-benzene-... A new coordination polymer {[Cd(C_(21)H_(14)N_6)(C_8H_4O_4)]·H_2O}_n(1) was synthesized by an elaborate design via the reaction of 3-(2,6-di(pyrazin-2-yl)pyridin-4-yl)-1H-indole(bppi),1,4-benzene-dicarboxylic acid(H2bdc) and cadmium(Ⅱ) nitrate in CH_3OH/H_2O mixed solvents. Complex 1 crystallizes in orthorhombic,space group Ccca with a = 20.012(4),b = 31.881(6),c = 19.808(4) ?,V = 12638(4) ?~3,Z = 16,C_(29)H_(20)CdN_6O_5,M_r = 644.91,D_c = 1.356 g·cm^(-3),μ = 0.735 mm^(-1),F(000) = 5184,GOOF = 1.046,the final R = 0.0405 and wR = 0.1063 for 6870 observed reflections(I 〉 2σ(I)). The Cd(Ⅱ) centre is hepta-coordinated by three N and four O atoms from one bppi terminal ligand and two bdc2– ligands,respectively,displaying a capped trigonal prism geometry. Structure extension gives coordination polymeric chains,in which the bdc2– linkers connect Cd(Ⅱ) cations into a one-dimensional(1D) coordination polymer along the c axis,giving zigzag chains with the Cd···Cd separation of 11.178(1) ?. The adjacent bppi terminal ligands in the chains are anti-periplanar conformation. The three-dimensional(3D) structure is stabilized by π···π stacking and hydrogen-bonding interactions to form a supramolecular self-penetrating network with 1D channels. In 1,there are voids 2999.7 ?~3 with 23.7% of per unit cell volume. Thermal analysis indicates that the framework of 1 is stable until 651 K and the photoluminescence of 1 in the solid shows very weak fluorescence at 382 and 560 nm upon excitation at 310 nm. 展开更多
关键词 1 4-benzenedicarboxylic acid 3-(2 6-di(pyrazin-2-yl)pyridin-4-yl)-1H-indole one-dimensional cadmium(Ⅱ) coordination polymer π···π stacking interactions photoluminescence
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Synthesis and Crystal Structure of 4-(4,6-dimethoxyl -pyrimidin-2-yl)-3-thiourea Carboxylic Acid Methyl Ester 被引量:1
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作者 HUANG Jie SONG Ji-Rong REN Ying-Hui XU Kang-Zhen MA Hai-Xia 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第2期168-172,共5页
The title compound 4-(4,6-dimethoxylpyrimidin-2-yl)-3-thiourea carboxylic acid methyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in eth... The title compound 4-(4,6-dimethoxylpyrimidin-2-yl)-3-thiourea carboxylic acid methyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray measurement were obtained by recrystallization with the solvent of dimethyl formamide at the room temperature. The structure was characterized by elemental analysis and IR and determined by X-ray diffraction analysis' Crystallographic data: C9H12N4O4S, Mr = 272.29, monoclinic, space group C2/m with a = 1.6672(3), b = 0.66383(12), c = 1.1617(2) nm, β = 109.275(2)°, V = 1.2136(4) nm^3, Dc = 1.490 g/cm^3,μ = 0.281 mm^-1, F(000) = 568, Z = 4, R1 = 0.0341and wR2 = 0.1042. 展开更多
关键词 4-(4 6-dimethoxylpyrimidin-2-yl)-3-thiourea carboxylic acid methyl ester synthesis X-ray diffraction
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CRYSTAL STRUCTURE OF BINUCLEAR Y(Ⅲ) COMPLEX WITH p-METHYLBENZOIC ACID, Y_2(p-CH_3C_6H_4COO)_6(C_(12)H_8N_2)_2 被引量:1
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作者 Rui Fen WANG Lin Pei JIN +3 位作者 Ming Zhao WANG Guan Liang CAI Shi Xiong LIU Jin Ling HUANG 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第11期861-862,共2页
Y_2(p-CH_3C_6H_4COO)_6(C_(12)H_8N_2)_2, Mr=1349.08, triclinic, space group P, a=13.00(3), b=19.743(2), c=12.754(3)A, α=97.94(1), β=106.24(2), γ=91.66(1)°, V=3177(1)~3, Z=2, Dc=1.41gcm^(-3), λ(MoKα)=0.71069, ... Y_2(p-CH_3C_6H_4COO)_6(C_(12)H_8N_2)_2, Mr=1349.08, triclinic, space group P, a=13.00(3), b=19.743(2), c=12.754(3)A, α=97.94(1), β=106.24(2), γ=91.66(1)°, V=3177(1)~3, Z=2, Dc=1.41gcm^(-3), λ(MoKα)=0.71069, μ=18.92 cm^(-1), F(ooo)=1384, T=295K, final R=0.073 for 6504 observed reflections with Ⅰ>36(Ⅰ). There are two nonidentical binuclear molecules with different bridging connection patterns in a cell. One has four bridging carboxyl groups bound two Y(Ⅲ) ions and another only has two. The Y-Y distance is 4.196 for the former and 5.302 for the latter respectively. 展开更多
关键词 p-CH3C6H4COO CRYSTAL STRUCTURE OF BINUCLEAR Y H8N2 Y2 COMPLEX WITH p-METHYLBENZOIC acid CH
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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,Crystal Structure and Antifungal Activity of N-(Pyridine-2-methyl)-2-(4-chlorophenyl)-3-methylbutanamide
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作者 陈龙 薛思佳 +2 位作者 方治坤 尹安琴 胥杨 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第8期990-994,共5页
A novel compound N-(pyridine-2-methyl)-2-(4-chlorophenyl)-3-methylbutanamide, a racemic compound, has been synthesized with 2-(4-chlorophenyl)-3-methylbutyric acid and pyridin- 2-methylanamine as the raw materia... A novel compound N-(pyridine-2-methyl)-2-(4-chlorophenyl)-3-methylbutanamide, a racemic compound, has been synthesized with 2-(4-chlorophenyl)-3-methylbutyric acid and pyridin- 2-methylanamine as the raw materials, and its crystal structure (C17H19C1N2O, Mr = 302.79) was determined by single-crystal X-ray diffraction analysis. The crystal belongs to monoclinic, space group P21/n with a = 9.624(9), b = 23.14(2), c = 15.626(15)A, β = 106.199(14)°, V = 3342(5) A^3, Z = 8, Dc = 1.204 g/cm^3,μ = 0.23 mm^-1, F(000) = 1280, S = 1.032, R = 0.0681 and wR = 0.1508 for 6513 unique reflections (Rint = 0.0421) with 3375 observed ones. In the crystal structure, there are some intermolecular hydrogen bonds which stabilize the crystal structure. The preliminary bioassay shows that the title compound exhibits good antifungal activity against Botrytis cinerea, Gibberella zeae, Dothiorella gregaria and Colletotrichum gossypii. 展开更多
关键词 2-(4-chlorophenyl)-3-methylbutyric acid crystal structure SYNTHESIS antifungaiactivity
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Crystal Structure and Biological Activities of (R)-N′-[2-(4-Methoxy-6-chloro)-pyrimidinyl]-N-[3-methyl-2-(4-chlorophenyl)butyryl]-urea
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作者 LI Jing-Zhi XUE Si-Jia LIU Guo-Hua 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第8期903-908,共6页
The title compound (R)-N′-[2-(4-methoxy-6-chloro)-pyrimidyl]-N-[3-methyl-2-(4- chlorophenyl)butyryl]-urea has been synthesized, and its crystal structure and biological behaviors were studied. Crystallographic ... The title compound (R)-N′-[2-(4-methoxy-6-chloro)-pyrimidyl]-N-[3-methyl-2-(4- chlorophenyl)butyryl]-urea has been synthesized, and its crystal structure and biological behaviors were studied. Crystallographic data: C17H18C12N4O3, Mr = 397.25, monoclinic, space group P21/c, a = 12.331(2), b = 14.025(3), c = 23.085(5) A, β = 99.607(4)°, Z = 8, V = 3936.2(13) A3, Dc = 1.341 g/cm^3, F(000) = 1648, R = 0.0718, wR = 0.1585 and/t(MoKα) = 0.353 mm^-1. The preliminary biological tests showed that the title compound has definite insecticidal and fungicidal activities. 展开更多
关键词 crystal structure biological activity (R)-3-methyl-2-(4-chlorophenyl)butyric acid 2-amino-6-chloro-4-methoxy-pyrimidine
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Synthesis of (S)-2-(3-Arylacrylamido)-3-{4-[2-(5-methyl-2-phenyl-oxazol-4-yl)ethoxy]phenyl}propanoic Acids
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作者 Xin Bo ZHOU Cui Fang LIN Song LI 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第10期1301-1304,共4页
The synthesis of (S)-2-(3-arylacrylamido)-3-{4-[2-(5-methyl-2-phenyloxazol-4-yl)etho- xy]phenyl}propanoic acids is described. Their structures were confirmed by ^1H-NMR.
关键词 (S)-2-(3-Arylacrylamido)-3-{4-[2-(5-methyl-2-phenyloxazol-4-yl)ethoxy]phenylpropanoic acids synthesis.
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