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三萜类化合物Bardoxolone methyl对急性呼吸窘迫综合征大鼠氧化应激信号通路Nrf2-ARE/HO-1的影响 被引量:1
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作者 谭国良 刘玉琪 《中国急救医学》 CAS CSCD 北大核心 2019年第3期269-273,共5页
目的观察三萜类化合物Bardoxolone methyl(BARD)对急性呼吸窘迫综合征(ARDS)大鼠氧化应激信号通路核转录因子相关因子2(Nrf2-ARE)/血红素氧合酶-1(HO-1)的影响。方法100只大鼠按随机数字法分为药物BARD组及生理盐水组,喂养一周后两组按... 目的观察三萜类化合物Bardoxolone methyl(BARD)对急性呼吸窘迫综合征(ARDS)大鼠氧化应激信号通路核转录因子相关因子2(Nrf2-ARE)/血红素氧合酶-1(HO-1)的影响。方法100只大鼠按随机数字法分为药物BARD组及生理盐水组,喂养一周后两组按是否建立ARDS模型再各分为两亚组,产生四组:ARDS模型+BARD干预组(A1组),ARDS模型+生理盐水组(A2组),正常+BARD干预组(B1组),正常+生理盐水组(B2组)。各组大鼠再喂养72h后处死留取肺组织及血液标本。病理观察肺组织结构变化。免疫组织化学检测肺组织Nrf2、HO-1蛋白表达情况。反转录-多聚酶链反应(RT-PCR)检测肺组织Nrf2 mRNA、HO-1 mRNA表达情况。结果肺组织病理结构变化:A2组肺组织损伤程度最重,病理评分最高。其次A1组,B1及B2组结构大致正常。Nrf2、HO-1蛋白表达情况:A1组(3.78±0.37,2.86±0.16)及B1组(3.01±0.34,2.47±0.19)高于A2(1.82±0.31,2.01±0.21)及B2组(0.92±0.13,1.41±0.17),A1组高于B1组,A2组高于B2组(P均<0.05)。Nrf2mRNA、HO-1mRNA表达情况:A1组(2.16±0.17,1.45±0.12)最为明显,B1组(1.79±0.14,1.18±0.05)高于B2组(0.42±0.06,0.68±0.11),A2组(1.18±0.19,1.01±0.07)高于B2组(0.42±0.06,0.68±0.11,P均<0.05)。结论三萜类化合物Bardoxolone methyl能够明显上调肺组织Nrf2-ARE/HO-1信号通路相关蛋白的表达,从而发挥抗氧化应激作用,减轻ARDS时肺组织的损伤。 展开更多
关键词 三萜类化合物 Bardoxolone methyl 急性呼吸窘迫综合征(ARDS) 血红素氧合酶-1(HO-1) 核转录因子相关因子2(Nrf2-ARE)
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Synthesis,Crystal Structure and Fungicidal Activity of(E)-2-[(4-tert-Butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)methyl]phenol 被引量:2
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作者 胡艾希 曹高 +2 位作者 马颍绮 张建宇 欧晓明 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第10期1235-1239,共5页
The title compound (E)-2-[(4-tert-butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)methyl]phenol was synthesized by the reaction of 5-(4-methoxybenzyl)-4-tert- butylthiazol-2-amine with salicylaldehyde, and its crys... The title compound (E)-2-[(4-tert-butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)methyl]phenol was synthesized by the reaction of 5-(4-methoxybenzyl)-4-tert- butylthiazol-2-amine with salicylaldehyde, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 5.9362(8), b = 11.5070(15), c = 29.460(4)A, β= 97.326(3)°, V = 1995.9(5) A^3, Z = 4, F(000) = 808, C22H24N2O2S, Mr= 380.49, De= 1.266 g/cm^3, S = 1.031,μ = 0.181 mm^-1, the final R = 0.0474 and wR = 0.1441 for 4327 observed reflections (I 〉 2σ(I)). Intramolecular O-H…N hydrogen bond is observed in the crystal. The preliminary bioassay showed that the title compound exhibits 95% inhibition rate against Rhizoctonia solani at the test concentration of 500 mg/L. 展开更多
关键词 crystal structure SYNTHESIS fungicidal activity (E)-2- [(4-tert-butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)methyl]phenol
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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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Synthesis and Crystal Structure of (Z)-Methyl-3-methoxy-2-{2-[(4-(E-3-p-tolylacryloyl)phenoxy)methyl]phenyl}acrylate 被引量:1
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作者 周中振 游文玮 赵培亮 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第10期1574-1578,共5页
The title compound,(Z)-methyl-3-methoxy-2-{2-[(4-(E-3-p-tolylacryloyl)phenoxy)-methyl]phenyl}acrylate,was synthesized and determined by X-ray single-crystal diffraction. The crystal belongs to the triclinic syst... The title compound,(Z)-methyl-3-methoxy-2-{2-[(4-(E-3-p-tolylacryloyl)phenoxy)-methyl]phenyl}acrylate,was synthesized and determined by X-ray single-crystal diffraction. The crystal belongs to the triclinic system,space group P1 with a = 8.0157(8),b = 12.5748(13),c = 13.3768(14) ,α = 64.770(2),β = 75.720 (2),γ = 89.784(2)°,μ = 0.085 mm-1,Mr = 442.49,V = 1174.1(2) 3,Z = 2,Dc = 1.252 g/cm3,F(000) = 468,T = 294(2) K,R = 0.0603 and wR = 0.1498 for 2644 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals that the single crystal contains strong non-classical hydrogen bonds. The preliminary bioassay showed that the title compound exhibits inhibitory activity against the Pseudoperoniospora cubensis and Rhizoctonia solani at the test concentration of 200 mg/L. 展开更多
关键词 synthesis crystal structure (Z)-methyl-3-methoxy-2-{2-[(4-(E-3-p-tolylacryloyl)phenoxy)methyl]phenyl}acrylate
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Synthesis, Structure and Quantum Mechanical Calculations of Methyl 2-(5-((Quinolin-8-yloxy)-methyl)-1,3,4-oxadiazol-2-ylthio)-acetate
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作者 AAMER SAEED FOUZIA PERVEEN +2 位作者 NAEEM ABBAS SIDRA JAMAL ULRICH FL?RKE 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第6期858-870,共13页
The title compound was synthesized by the base catalyzed reaction of 5-((quinolin- 8-yloxy)methyl)-1,3,4-oxadiazole-2(3H)-thione with methyl chloroacetate. The structure was supported by the spectroscopic data a... The title compound was synthesized by the base catalyzed reaction of 5-((quinolin- 8-yloxy)methyl)-1,3,4-oxadiazole-2(3H)-thione with methyl chloroacetate. The structure was supported by the spectroscopic data and unambiguously confirmed by single-crystal X-ray diffraction studies. It crystallizes from a methanol solution in the triclinic space group Pi with unit cell dimensions a = 7.4509(9), b = 10.2389(12), c = 12.2299(15)A, a = 74.771(2), β = 77.956(2), 7 = 69.263(2)°, V = 834.98(17) A3 and Z = 2. In order to gain some valuable insights into the molecular structure, the quantum mechanical calculations were performed using both HF and time-dependent density functional theory at the B3LYP/6-31G(d,p) level. The molecular geometry from X-ray determination of the title compound in the ground state has been compared using the Hartree-Fock (HF) and density functional theory (DFT) with the 6-31G(d) basis set. The calculated results show that the DFT and HF can well reproduce the structure of the title compound. The energetic behavior of the title compound was examined using the B3LYP method with the 6-31G(d) basis set. The harmonic vibrational frequencies calculated have been compared with the experimental FTIR and FT-Raman spectra. The restricted Hartree-Fock and density functional theory-based nuclear magnetic resonance (NMR) calculation procedure was also performed, and it was used for assigning the 13C and 1H NMR chemical shifts of the title compound. Moreover, molecular electrostatic potential and thermodynamic parameters of the title compound were investigated by theoretical calculations. 展开更多
关键词 methyl 2-(5-((quinolin-8-yloxy)methyl-1 3 4-oxadiazol-2-ylthio)acetate CRYSTALSTRUCTURE CONFORMER quantum chemical calculations vibrational studies
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Syntheses and Crystal Structures of Methyl 2-(4,5-Dibromo-1-methylpyrrole-2-carbonylamino)-3-phenylpropanoate and 4,5-Dibromo-1-methyl-2- trichloroacetylpyrrole
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作者 ZENG Xiang-Chao GU Jian XU Shi-Hai LIU Po-Run 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第2期153-158,共6页
4,5-Dibromo-1-methyl-2-trichloroacetylpyrrole Ⅰ, prepared by the reaction of 1-methyl-2-trichloroacetylpyrrole with Br2 in 98.6 % yield, was condensed with methyl L-2-amino-3- phenylpropanoate to afford methyl 2-(4,... 4,5-Dibromo-1-methyl-2-trichloroacetylpyrrole Ⅰ, prepared by the reaction of 1-methyl-2-trichloroacetylpyrrole with Br2 in 98.6 % yield, was condensed with methyl L-2-amino-3- phenylpropanoate to afford methyl 2-(4,5-dibromo-1-methylpyrrole-2-carboxmido)-3-phenylpropanoate Ⅱ in 90.8% yield. Crystal data for Ⅰ: monoclinic system, space group P21/c with a = 8.595(3), b = 10.900(4), c = 12.321(5) ,A°,β = 92.292(7)°, V = 1153.4(8)A°^3, Dc = 2.213 g/cm^3, F(000) = 728, CTH4Br2Cl3NO, Mr = 384.28, λ = 0.71073 A°, μ(MoKa) = 7.688 mm^-1, Z = 4, R = 0.0338 and wR2 = 0.0840 for 1963 observed reflections with I 〉 2a(I). Crystal data for Ⅱ: monoclinic system, space group P21 with a = 4.886(2), b = 15.921(8), c = 11.635(6) A°,β = 101.803(9)°, V = 885.9(7) A°^3, Dc = 1.665 g/cm^3, F(000) = 440, C16H16Br2N2O3, Mr = 444.13, λ = 0.71073 A°, μ(MoKa) = 4.590 mm^-1, Z = 2, R = 0.0335 and wR2 = 0.0837 for 3191 observed reflections with I 〉 2σ(I). The crystal structure reveals that compound Ⅱ forms the one-dimensional chain structure via the intermolecular hydrogen bonds of N(2)-H…O(1). 展开更多
关键词 methyl 2-(4 5-dibromo-1-methylpyrrole-2-carbonylamino)-3-phenylpropanoate synthesis crystal structure 4 5-dibromo-1-methyl-2-trichloroacetylpyrrole
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Synthesis and Crystal Structure of Methyl 2-(Diphenylamino)-4-phenyl-1,3-thiazole-5-carboxylate
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作者 Ali Souldozi Seyed Hamid Reza Shojaei +2 位作者 Ali Ramazani Katarzyna lepokura Tadeusz Lis 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第1期82-88,共7页
The title compound, methyl 2-(diphenylamino)-4-phenyl-1,3-thiazole-5-carboxylate, was synthesized and studied by single-crystal X-ray diffraction method. The structure of the product was confirmed by IR, 1H- and 13C... The title compound, methyl 2-(diphenylamino)-4-phenyl-1,3-thiazole-5-carboxylate, was synthesized and studied by single-crystal X-ray diffraction method. The structure of the product was confirmed by IR, 1H- and 13C-NMR spectroscopy and elemental analysis. These experimental studies were supported by quantum mechanical calculations. The structure was solved in monoclinic, space group P21/c with a = 9.573(3), b = 19.533(7), c = 9.876(3), β = 92.35(4)°, V = 1845.2(10)3, T = 85(2) K, Z = 4, R = 0.040 and wR = 0.089 for 6424 observed reflections with I2σ(I). 展开更多
关键词 single-crystal X-ray structure multi-component reaction methyl 2-(diphenylamino)-4-phenyl-1 3-thiazole-5-carboxylate benzoyl isothiocyanate DIPHENYLAMINE dimethyl acetylenedicarboxylate
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Synthesis and Crystal Structure of N-((6-chloropyridin-3-yl)methyl)-6-ethoxy-N-ethyl-3-nitropyridin-2-amine
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作者 吴道新 刘民华 +6 位作者 柳爱平 黄明智 胡志彬 任叶果 刘兴平 唐明 左文清 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第5期621-624,共4页
The title compound N-((6-chloropyridin-3-yl)methyl)-6-ethoxy-N-ethyl-3-nitropyri-din-2-amine(4) was synthesized by reacting the mixture of 6-chloro-2-ethoxy-3-nitropyridine(1) and 2-chloro-6-ethoxy-3-nitropyri... The title compound N-((6-chloropyridin-3-yl)methyl)-6-ethoxy-N-ethyl-3-nitropyri-din-2-amine(4) was synthesized by reacting the mixture of 6-chloro-2-ethoxy-3-nitropyridine(1) and 2-chloro-6-ethoxy-3-nitropyridine(2) with 3,and its structure was determined by X-ray single-crystal diffraction.The crystal belongs to the monoclinic system,space group P21/n with a = 7.3441(2),b = 9.9041(3),c = 11.7368(3) ,α = 101.410(2),β = 102.1340(10),γ = 99.594(2)o,μ = 0.260 mm^-1,Mr = 336.78,V = 798.58(4)(A°)^3,Z = 2,Dc = 1.401g/cm^3,F(000) = 352,T = 296(2) K,R = 0.0210 and wR = 0.1053. 展开更多
关键词 synthesis crystal structure N-((6-chloropyridin-3-yl)methyl-6-ethoxy-N-ethyl-3-nitropyridin-2-amine insecticidal and fungicidal activities
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Synthesis and Crystal Structure of 1,4-Dimethyl-2,5-di{[2’-(3-pyridylmethylamino-formyl)phenoxyl]methyl}benzene Perchlorate
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作者 唐宽镇 唐瑜 +2 位作者 李亚飞 刘伟生 谭民裕 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第4期451-454,共4页
The title compound, 1,4-dimethyl-2,5-di { [2′-(3-pyridylmethylaminoformyl)phenoxyl]- methyl}benzene perchlorate (C36H36Cl2N4O12, Mr = 787.59), has been synthesized and structurally determined by single-crystal X-... The title compound, 1,4-dimethyl-2,5-di { [2′-(3-pyridylmethylaminoformyl)phenoxyl]- methyl}benzene perchlorate (C36H36Cl2N4O12, Mr = 787.59), has been synthesized and structurally determined by single-crystal X-ray diffraction. The crystal crystallizes in the orthorhombic system, space group Pbca with a = 14.366(4), b = 15.159(4), c = 16.443(5)A, V = 3580.9(17)/A3 Z = 4, De = 1.461 g/cm^3, /t = 0.253 mm^-1, F(000) = 1640, R = 0.0618 and wR = 0.1525 for 1615 observed reflections (I 〉 2σ(I)). In the structure of the title compound, a two-dimensional supramolecular layer is formed via intermolecular hydrogen bonding interactions. 展开更多
关键词 2 5-dimethyl-l 4-di{ [2-(3-pyridylmethylaminoformyl)phenoxyl]methyl)benzene synthesis spectral characterization crystal structure
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固载化猪胰脂肪酶的制备及其在2-氯丙酸甲酯水解中应用 被引量:4
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作者 施介华 蔡栋材 叶蒙 《浙江工业大学学报》 CAS 北大核心 2009年第1期32-35,共4页
采用载体表面涂布法制备固载化猪胰脂肪酶并应用于2-氯丙酸甲酯的水解,主要考察了固载化过程中不同载体、加酶量、温度及pH值对固载化酶活力的影响.确定了固载化最佳工艺条件为:以硅胶为载体,pH值为7.2,温度为40℃,m(酶)∶m(载体)=1∶3... 采用载体表面涂布法制备固载化猪胰脂肪酶并应用于2-氯丙酸甲酯的水解,主要考察了固载化过程中不同载体、加酶量、温度及pH值对固载化酶活力的影响.确定了固载化最佳工艺条件为:以硅胶为载体,pH值为7.2,温度为40℃,m(酶)∶m(载体)=1∶3.在所选择的固载化条件下制备的固载化猪胰脂肪酶的酶活力为150 IU.固载化猪胰脂肪酶(200 mg)用于2-氯丙酸甲酯(5mmol/50 mL,pH=7.2)进行水解,4 h水解率为10.5%,(R)-氯代丙酸的ee值达87%,与游离猪胰脂肪酶的光学选择性基本一致. 展开更多
关键词 猪胰脂肪酶 固载化 2-氯丙酸甲酯 2-氯丙酸 水解
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2-氯丙酸法制备甲基丙二酸二乙酯 被引量:1
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作者 范崇光 高复兴 +2 位作者 马峰 王寿柏 葛存旺 《信阳师范学院学报(自然科学版)》 CAS 2000年第3期344-345,共2页
以 2 -氯丙酸为原料 ,经氰化、水解、酯化制得甲基丙二酸二乙酯 ,总收率 41 % .
关键词 甲基丙二酸二乙酯 合成 2-氯丙酸
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Vilsmeir-Hack试剂合成光学纯2-氯丙酸甲酯 被引量:1
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作者 文辉 王敏 《化学试剂》 CAS CSCD 北大核心 2005年第8期491-492,共2页
使用Vilsmeir-Hack试剂合成光学纯的(R)2-氯丙酸甲酯,通过考察各种影响因素找到了反应的最优条件,产率达74%,e.e.可达98%。
关键词 Vilsmeir-Hack试剂 合成 光学纯 2-氯丙酸甲酯
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R-2-氯丙酸甲酯的合成 被引量:1
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作者 陈桂荣 陈玉斌 《化学工程师》 CAS 2013年第4期70-71,共2页
本实验采用光学纯度的乳酸甲酯为起始原料,二氯亚砜为卤置换试剂在吡啶的条件制备目标化合物R-2-氯丙酸甲酯,并通过对反应条件进行较详细的考察,确定目标化合物的最佳合成工艺条件。
关键词 乳酸甲酯 二氯亚砜 R-2-氯丙酸甲酯 合成 工艺条件
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LC-MS^n测定2-[[(2′-氰基联苯基)-4-基]甲基]氨基-3-硝基苯甲酸乙酯中的不纯物
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作者 姚骏骅 《分析测试学报》 CAS CSCD 北大核心 2007年第z1期125-126,共2页
The impurities in ethyl-2-[[2′-cyanobiphenyl-4-yl] methyl] amino]-3-nitrobenzoate,an intermediate for synthesis of candesartan cilexiti,were detected by LC-MSn. The structural assignment of these impurities was carri... The impurities in ethyl-2-[[2′-cyanobiphenyl-4-yl] methyl] amino]-3-nitrobenzoate,an intermediate for synthesis of candesartan cilexiti,were detected by LC-MSn. The structural assignment of these impurities was carried out by LC-MSn using electrospray ionization source and an ion trap mass analyzer. The formation of the impurities was discussed. Also the fragmentation pathways of these compounds were studied. 展开更多
关键词 LC-MSn Ethyl-2-[[2-cyanobiphenyl-4-yl] methyl] amino]-3-nitrobenzoate IMPURITIES Fragmentation pathways
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2-羟基-4-(5,6-二硝基-1H-苯并[2,3-d]咪唑-2-基)苯甲酸甲酯的合成探索 被引量:3
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作者 张青龙 金宁人 +2 位作者 杨健 张清义 张建庭 《化工进展》 EI CAS CSCD 北大核心 2014年第3期744-748,757,共6页
以4,5-二硝基邻苯二胺和2-羟基对苯二甲酸单甲酯为起始原料,设计并成功采用一锅法合成出2-羟基-4-(5,6-二硝基-1H-苯并[2,3-d]咪唑-2-基)苯甲酸甲酯(MHDIB)。以50 mL二乙二醇二甲醚为溶剂,1.5 g的2-羟基对苯二甲酸单甲酯和2.5 g SOCl2... 以4,5-二硝基邻苯二胺和2-羟基对苯二甲酸单甲酯为起始原料,设计并成功采用一锅法合成出2-羟基-4-(5,6-二硝基-1H-苯并[2,3-d]咪唑-2-基)苯甲酸甲酯(MHDIB)。以50 mL二乙二醇二甲醚为溶剂,1.5 g的2-羟基对苯二甲酸单甲酯和2.5 g SOCl2在80℃反应2 h制2-羟基-4-氯羰基苯甲酸甲酯。室温下快速向反应体系中加入1.56 g 4,5-二硝基邻苯二胺,并于85℃反应1 h后加入3.52 g多聚磷酸,回流反应1 h后水析出粗产品,经乙醇重结晶得到纯度为93.67%的黄色针状产物,产率为17.82%。产物经IR、MS、1H NMR的准确定性和表征,作为AB型新单体的前体可应用于羟基改性PBI纤维即聚2-羟基-1,4-亚苯基-2,6-苯并[2,3-d:5',6'-d']二咪唑(H-PBI)的创新研究。 展开更多
关键词 2-羟基-4-(5 6-二硝基-1H-苯并2 3-d咪唑-2-基)苯甲酸甲酯 4 5-二硝基邻苯二胺 羟基改性PBI纤维 聚合 合成 纯化 methyl 2-hydrox yl-4-(5 6-dinitro-1H-benzo[2 3-d]imidazole-2-yl)benzoate(MHDIB)
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Effects of Zr/Ti molar ratio in SO_4^(2-)/ZrO_(2-)TiO_2 calcined at different temperatures on its surface properties and glucose reactivity in near-critical methanol 被引量:3
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作者 Lincai Peng Junping Zhuang Lu Lin 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第2期138-147,共10页
Effects of Zr/Ti molar ratio in SO42-/ZrO2-TiO2 solid acid catalyst calcined at different temperatures on its surface properties and catalytic activity were thoroughly investigated in this paper. The physicochemical c... Effects of Zr/Ti molar ratio in SO42-/ZrO2-TiO2 solid acid catalyst calcined at different temperatures on its surface properties and catalytic activity were thoroughly investigated in this paper. The physicochemical characteristics of prepared samples were determined by N2 adsorptiondesorption, XRD, NH3-TPD and XPS techniques, respectively. It was found that the crystallization temperature of the samples increased after the combination of ZrO2 and TiO2; and phase transformations from the anatase to the rutile of TiO2 species and the tetragonal to the monoclinic of ZrO2 species were effectively suppressed at higher temperature. The sample with a Zr/Ti molar ratio of 3/1 calcined at 450℃ showed the highest surface area and the most acid sites among all the tested samples. The acid site densities of samples were relatively closed to each other if they were calcined at the same temperature, however, decreased with the calcination temperature. The result indicates that the sulfur content in samples is a crucial factor to control the acid site density. Calcining the sample at 650℃ and higher temperatures resulted in a significant desorption of sulfate ion on the samples. The synthesized samples were evaluated as a potential catalyst for glucose conversion under the near-critical methanol conditions (200℃/4 MPa). The results suggested that the relatively weaker acid sites of the catalyst were more favorable for the accumulation of methyl glucosides, while the moderate acid sites were responsible for the formation of methyl levulinate. The catalytic activity for methyl levulinate production almost increases linearly with the catalyst acid site density. The catalyst deactivation is due to the loss of sulfate ion and the two catalysts with Zr/Ti molar ratios of 3/1 and 1/3 could effectively alleviate the deactivation caused by sulfate solution in the reaction medium and can be reused after calcination with the reuse rate of over 90% in terms of the methyl levulinate selectivity. 展开更多
关键词 SO42-/ZrO2-TiO2 surface properties catalysis glucose reactivity methyl levulinate
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Vilsmeier试剂合成S-2-氯丙酸甲酯新工艺研究
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作者 周明芳 李斌栋 《现代农药》 CAS 2013年第5期15-17,共3页
以R-乳酸甲酯为原料,以氯化亚砜和DMF形成的Vilsmeier试剂为氯化剂,以DMF为催化剂兼溶剂,经亲核取代反应合成S-2-氯丙酸甲酯。主要考查R-乳酸甲酯和Vilsmeier试剂物质的量之比、反应温度、反应时间、溶剂种类等因素对收率的影响,优... 以R-乳酸甲酯为原料,以氯化亚砜和DMF形成的Vilsmeier试剂为氯化剂,以DMF为催化剂兼溶剂,经亲核取代反应合成S-2-氯丙酸甲酯。主要考查R-乳酸甲酯和Vilsmeier试剂物质的量之比、反应温度、反应时间、溶剂种类等因素对收率的影响,优化了工艺条件。结果表明:当Vilsmeier试剂与R-乳酸甲酯物质的量之比为1.15∶1,反应温度为50~60℃,反应时间为5 h时,较传统的氯化亚砜/吡啶/PCl5/POCl3氯化体系,收率从72%提高到89%,光学纯度(e.e%)达98.2%。并用FT-IR,1H NMR,GC-MS表征了其分子结构。 展开更多
关键词 S-2-氯丙酸甲酯 R-乳酸甲酯 Vilsmeier试剂 氯化
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Synthesis,Structure,and Magnetic Property of One Snake-shaped Copper(Ⅱ)-organic Compound:Cu[Cu_2(PP)_2](CBPC)_2]·2(H_2O) 被引量:3
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作者 范黎明 李大成 +2 位作者 魏培海 张修堂 窦建民 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第10期1381-1386,共6页
One novel copper(II)-organic compound,namely Cu[Cu2(PP)2](CBPC)2]·2(H2O)(1,H2CBPC = 1-[(2'-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid,HPP = 3-(2-pyridyl)pyrazole),was designed... One novel copper(II)-organic compound,namely Cu[Cu2(PP)2](CBPC)2]·2(H2O)(1,H2CBPC = 1-[(2'-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid,HPP = 3-(2-pyridyl)pyrazole),was designed and synthesized under hydrothermal conditions.X-ray diffraction analysis reveals that two Cu(II)ions in the quasi-planar dimmer of [Cu2(PP)2] are linked by the carboxylate oxygen atoms on the phenyl ring and the imidazole ring,respectively,yielding one snake-shaped structure.Magnetic measurements reveal that compound 1 shows the strongly antiferromagnetic property.Crystal data of 1:C58H52Cu3N10O10,Mr = 1239.72,monoclinic,P21/c,a = 14.900(7),b = 15.029(7),c = 12.308(6),β = 102.519(9)o,V = 2691(2)3,Z = 2,Dc = 1.530 g/cm3,F(000)= 1274,μ = 1.246 mm-1,R = 0.0416,wR = 0.0780(I 2σ(I))and S = 0.999. 展开更多
关键词 1-[(2-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid 3-2-pyridyl)pyrazole) copper(II) magnetism TGA XPS
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Hydrothermal Synthesis and Crystal Structure of One Novel 1-D Copper(Ⅱ)-organic Framework:{[Cu_2(PP)_2(CBPC)]_2·7H_2O}_n 被引量:2
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作者 魏培海 吴小园 +5 位作者 范黎明 李大成 张修堂 窦建民 刘新征 石聪文 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第12期1774-1779,共6页
One novel 1-D copper(Ⅱ)-organic compound,namely {[Cu2(PP)2(CBPC)]2·7H2O}n(1,H2CBPC=1-[(2'-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid,HPP=3-(2-pyridyl)pyrazole),was synthesized ... One novel 1-D copper(Ⅱ)-organic compound,namely {[Cu2(PP)2(CBPC)]2·7H2O}n(1,H2CBPC=1-[(2'-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid,HPP=3-(2-pyridyl)pyrazole),was synthesized under hydrothermal conditions.X-ray diffraction analyses reveal that the two Cu(Ⅱ) ions in the distorted dimer [Cu2(PP)2] of 1 are linked by the carboxylate oxygen atoms on the phenyl and imidazole rings,respectively,forming one interesting snake-like chain.Single-crystal X-ray analyses reveal that it crystallizes in monoclinic,space group C2/c with a=30.656(8),b=12.715(3),c=22.405(5),β=122.758(3)°,V=7344(3)3,Z=4,Mr=1681.65,Dc=1.521 g/cm3,F(000)=3464,μ=1.221 mm-1,the final R=0.0453 and wR=0.1023 for 4617 observed reflections with Ⅰ 〉2σ(Ⅰ). 展开更多
关键词 1-[(2-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid 3-2-pyridyl)pyrazole) copper(Ⅱ) TGA XPS crystal structures
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Chemistry and Application of Phosphonium and Arsonium Ylide(ⅩⅧ)——Stereoselective Syntheses of (Z)-3-Perfluoroalkyl--4-(3-Carboethoxy-2-f uranyl )-3-Butenoates
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作者 DING Wei-yu , CAO Wei-guo, ZHU Dian-kui and TONG Wei-qi (Department of Chemistry, Shanghai University of Science and Technology, Shanghai, 201800) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1992年第3期224-230,共7页
The stereoselective syntheses of (Z)-methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-3-butenoates 5a-c were investigated. The reaction of (3-carboethoxy-2-fu-ranyl)-methyltriphenylphosphonium bromide 1 with methyl... The stereoselective syntheses of (Z)-methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-3-butenoates 5a-c were investigated. The reaction of (3-carboethoxy-2-fu-ranyl)-methyltriphenylphosphonium bromide 1 with methyl 2-perfluoroalkynoates 2a-c in the presence of K2CO3 at room temperature gives two adducts, (E)-methyl 3-per-fluoroalkyl-4-( 3-carboethoxy-2-furanyl )-2-triphenylphosphoranylidene-3-butenoates 3a-c and (E)-methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-4-triphenylphos-phoranylidene-2-butenoates 4a-c. (Z)-Methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-3-butenoates 5a-c can be synthesized stereoselectively with high yields when an aqueous DMF solution of 3c, 4c or a mixture of 3a-b and 4a-b was heated at 140℃ for 8 h. 展开更多
关键词 (Z)-3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-3-butenoate Phospho-rane methyl 2-perfluoroalkynoate Hydrolysis Stereoselective synthesis
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