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Traditional Chinese medicine Pien-Tze-Huang ameliorates LPS-induced sepsis through bile acid-mediated activation of TGR5-STAT3-A20 signalling
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作者 Bei Li Yong Zhang +9 位作者 Xinyuan Liu Ziyang Zhang Shuqing Zhuang Xiaoli Zhong Wenbo Chen Yilin Hong Pingli Mo Shuhai Lin Shicong Wang Chundong Yu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第4期601-614,共14页
Pien Tze Huang(PZH),a class-1 nationally protected traditional Chinese medicine(TCM),has been used to treat liver diseases such as hepatitis;however,the effect of PZH on the progression of sepsis is unknown.Here,we re... Pien Tze Huang(PZH),a class-1 nationally protected traditional Chinese medicine(TCM),has been used to treat liver diseases such as hepatitis;however,the effect of PZH on the progression of sepsis is unknown.Here,we reported that PZH attenuated lipopolysaccharide(LPS)-induced sepsis in mice and reduced LPS-induced production of proinflammatory cytokines in macrophages by inhibiting the activation of mitogen-activated protein kinase(MAPK)and nuclear factor-kappa B(NF-κB)signalling.Mechanistically,PZH stimulated signal transducer and activator of transcription 3(STAT3)phosphorylation to induce the expression of A20,which could inhibit the activation of NF-κB and MAPK signalling.Knockdown of the bile acid(BA)receptor G protein-coupled bile acid receptor 1(TGR5)in macrophages abolished the effects of PZH on STAT3 phosphorylation and A20 induction,as well as the LPS-induced inflammatory response,suggesting that BAs in PZH may mediate its anti-inflammatory effects by activating TGR5.Consistently,deprivation of BAs in PZH by cholestyramine resin reduced the effects of PZH on the expression of phosphorylated-STAT3 and A20,the activation of NF-κB and MAPK signalling,and the production of proinflammatory cytokines,whereas the addition of BAs to cholestyramine resin-treated PZH partially restored the inhibitory effects on the production of proinflammatory cytokines.Overall,our study identifies BAs as the effective components in PZH that activate TGR5-STAT3-A20 signalling to ameliorate LPS-induced sepsis. 展开更多
关键词 Pien Tze Huang Bile acids SEPSIS Inflammation TGR5 STAT3-A20 signalling
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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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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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Gal-3、SFRP5、H-FABP联合检测对冠心病患者预后评估的临床价值 被引量:7
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作者 刘闯 闫佩佩 +1 位作者 陈雅丽 李向辉 《中国循证心血管医学杂志》 2023年第1期102-105,共4页
目的探讨血清半乳糖凝聚素-3(Gal-3)、分泌型卷曲蛋白5(SFRP5)、心型脂肪酸结合蛋白(H-FABP)联合检测对冠状动脉粥样硬化性心脏病(冠心病)患者预后评估的临床价值。方法选择2020年1月至2022年6月于郑州大学第一附属医院心内科就诊的83... 目的探讨血清半乳糖凝聚素-3(Gal-3)、分泌型卷曲蛋白5(SFRP5)、心型脂肪酸结合蛋白(H-FABP)联合检测对冠状动脉粥样硬化性心脏病(冠心病)患者预后评估的临床价值。方法选择2020年1月至2022年6月于郑州大学第一附属医院心内科就诊的83例冠心病患者作为病例组,根据冠心病类型将其分为稳定型心绞痛组(n=21),不稳定型心绞痛组(n=45)和心肌梗死组(n=17);根据临床随访,记录心源性死亡、心肌梗死、病变血管再狭窄以及支架血栓等将患者分为预后不良组(n=18)和预后良好组(n=65)。另选择同期我院进行体检的50例健康人群作为对照组,分析两组血清Gal-3、SFRP5、H-FABP水平变化情况及其临床价值。结果病例组患者血清SFRP5水平显著低于对照组,Gal-3、H-FABP水平均显著高于对照组,差异有统计学意义(P<0.05)。稳定型心绞痛组Gal-3、H-FABP水平均显著低于不稳定型心绞痛组和心肌梗死组,SFRP5水平显著高于不稳定型心绞痛组和心肌梗死组。不稳定型心绞痛组Gal-3、H-FABP水平均显著低于心肌梗死组;SFRP5水平显著高于心肌梗死组,差异具有统计学意义(P<0.05)。预后不良组血清SFRP5水平均显著低于预后良好组,Gal-3、H-FABP水平均显著高于预后良好组,差异具有统计学意义(P<0.05)。ROC曲线分析结果显示,血清Gal-3预测冠心病患者不良预后的AUC为0.779,灵敏度为63.43%,特异度为67.40%,截断值为59.54 ng/L。血清SFRP5预测冠心病患者不良预后的AUC为0.963,灵敏度为81.40%,特异度为70.00%,截断值为4.87 mg/L;血清H-FABP预测冠心病患者不良预后的AUC为0.830,灵敏度为73.50%,特异度为69.00%,截断值为17.46 ng/ml,联合检测的特异度、准确度较单独检测更高(P<0.05)。结论冠心病患者血清中Gal-3、SFRP5、H-FABP的表达异常,在冠心病不良预后中具有一定的诊断价值,同时也为靶向药物的治疗提供了新思路。 展开更多
关键词 半乳糖凝聚素-3 分泌型卷曲蛋白5 心型脂肪酸结合蛋白 冠状动脉粥样硬化性心脏病
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血清Gal-3、α1-AGP、SFRP5水平与急性心肌梗死经皮冠状动脉介入治疗术后预后不良的关系 被引量:4
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作者 应晨 李金平 陈生弟 《临床和实验医学杂志》 2023年第16期1703-1706,共4页
目的探究血清半乳糖凝集素-3(Gal-3)、α1酸性糖蛋白(α1-AGP)、分泌型卷曲相关蛋白5(SFRP5)水平与急性心肌梗死(AMI)患者经皮冠状动脉介入治疗(PCI)术后预后结局的关系。方法回顾性选取2019年3月至2022年3月在上海交通大学医学院附属... 目的探究血清半乳糖凝集素-3(Gal-3)、α1酸性糖蛋白(α1-AGP)、分泌型卷曲相关蛋白5(SFRP5)水平与急性心肌梗死(AMI)患者经皮冠状动脉介入治疗(PCI)术后预后结局的关系。方法回顾性选取2019年3月至2022年3月在上海交通大学医学院附属瑞金医院行PCI的AMI患者150例,根据患者术后预后结局不同将患者分为两组:对照组(n=80,未发生主要不良心血管事件,预后较好)和观察组(n=70,发生主要不良心血管事件,患者预后不良)。收集两组患者的一般临床资料,采用酶联免疫吸附试验测定治疗前后患者的血清Gal-3、SFRP5水平,全自动胶乳免疫比浊法检测患者治疗前后的α1-AGP水平,比较两组间各指标差异。采用受试者工作特征(ROC)曲线探究血清Gal-3、α1-AGP、SFRP5水平对AMI患者PCI术后发生预后不良结局预后的预测价值。结果治疗14 d后,两组Gal-3、SFRP5水平均有所提高,α1-AGP有所降低,治疗后,观察组Gal-3、α1-AGP水平分别为(8.65±1.23)ng/mL、(152.20±10.10)mg/mL,均高于对照组[(7.89±1.21)ng/mL、(134.42±10.21)mg/mL],SFRP5水平为(19.12±0.24)ng/mL,低于对照组[(23.64±0.23)ng/mL],差异均有统计学意义(P<0.05)。ROC曲线结果显示,血清Gal-3、α1-AGP、SFRP5水平预测AMI患者术后预后不良的ROC曲线下面积分别为0.751、0.894、0.964,最佳截断值分别为7.955 ng/mL、140.590 mg/mL、21.475 ng/mL。结论AMI患者采取PCI术治疗后,血清Gal-3、α1-AGP、SFRP5水平可作为检测患者预后是否良好的指标,对观察PCI术后发生预后不良结局具有一定预测价值。 展开更多
关键词 半乳糖凝集素-3 Α1酸性糖蛋白 分泌型卷曲相关蛋白5 急性心肌梗死 经皮冠状动脉介入治疗
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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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A Lanthanide-transition Metal Coordination Polymer:{[CuEu(Hbidc)_2(H_2O)_4]·H_2O}_n(H_3bidc=1H-benzimidazole-5,6-dicarboxylic Acid) 被引量:2
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作者 周馨慧 黄维 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第4期496-501,共6页
The title complex 1,{[CuEu(Hbidc)2(H2O)4]·H2O}n(H3bidc = 1H-benzimidazole-5,6-dicarboxylic acid),has been solvothermally synthesized and structurally characterized by single-crystal X-ray diffraction.Comple... The title complex 1,{[CuEu(Hbidc)2(H2O)4]·H2O}n(H3bidc = 1H-benzimidazole-5,6-dicarboxylic acid),has been solvothermally synthesized and structurally characterized by single-crystal X-ray diffraction.Complex 1 crystallizes in triclinic,space group P1,with a = 7.791(2),b = 12.058(3),c = 12.109(3),α = 82.189(5),β = 72.407(5),γ = 89.184(4)°,V = 1073.7(5)3,C18H18CuEuN4O13,Mr = 713.86,Dc = 2.208 g/cm3,μ(MoKα) = 3.967 mm-1,F(000) = 700,GOOF = 0.950,Z = 2,the final R = 0.0531 and wR = 0.1068 for I 2σ(I).Complex 1 possess a tape-like chain structure consisting of Eu2C8O4 and Cu2Eu2C18N4O4 metallic rings alternatively arranged and is the first 3d-4f heterometallic complex based on the 1H-ben-zimidazole-5,6-dicarboxylato ligand(Hbidc).Plenty of hydrogen-bonding and π...π stacking interactions connect the 1D chains to construct a 3D supramolecular architecture. 展开更多
关键词 1H-benzimidazole-5 6-dicarboxylic acid 3d-4f HETEROMETALLIC complex Cu+ Eu3
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A Novel Three-dimensional Mn(Ⅱ) Coordination Polymer Constructed from Biphenyl-3,3',5,5'-tetracarboxylic Acid and Water 被引量:1
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作者 李少东 卢丽萍 苏峰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第12期1920-1928,共9页
The title Mn(Ⅱ) coordination polymer,poly{[heptaaqua-(μ4-bi-phenyl-3,3?,5,5?-tetracarboxylate)-bimanganese(Ⅱ)] pentahydrate},[Mn_2(bpta)(H_2O)_7]_n·5n H_2O(I),is crystallized from a mixture of bi... The title Mn(Ⅱ) coordination polymer,poly{[heptaaqua-(μ4-bi-phenyl-3,3?,5,5?-tetracarboxylate)-bimanganese(Ⅱ)] pentahydrate},[Mn_2(bpta)(H_2O)_7]_n·5n H_2O(I),is crystallized from a mixture of biphenyl-3,3?,5,5?-tetracarboxylic acid(H_4bpta) and MnCl_2·4H_2O in waterethanol under room temperature. Its asymmetric unit consists of one and two halves of crystallographically independent Mn(Ⅱ) cations,one fully deprotonated H4 bpta ligand,seven coordinated water molecules and five solvent water as guest molecules. In I,each Mn(Ⅱ) atom is octahedrally coordinated by six oxygen atoms from bpta^(4-) anions and coordinated water molecules. In the Mn(Ⅱ) cations,one half Mn(Ⅱ) ion of them located at a 2-fold axis generating a trinuclear [Mn_3(H_2O)_2(RCOO)_2] linker by μ1,1-O(water) and μ1,3-O,O?(carboxylate) bridges and another half Mn(Ⅱ) ion with an inversion is a mononuclear linker. These neighbouring trinuclear and mononuclear Mn(Ⅱ) cations are linked together by biphenyl-3,3?,5,5?-tetracarboxylates to form a three-dimensional framework with a(42.84) topology of a(4,4)-connected net,in which the positions of the trinuclear [Mn_3(H_2O)_2(R-COO)_2] linker as a 4-connector linking four bpta^(4-) ligands in I reproduce an eagle-shaped arrangement. The polymeric structure exhibits a water channel with an accessible void of 797.1 ?~3,amounting to 15.7% of the total unit-cell volume. Each of the cavities in the network is occupied by solvent water molecules. 展开更多
关键词 Mn(Ⅱ) coordination polymer water cluster biphenyl-3 3' 5 5'-tetracarboxylic acid D2h symmetric carboxylate ligand topological structure
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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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1-甲基-3-正丙基-4-氨基-5-吡唑羧酰胺的制备 被引量:5
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作者 徐宝财 罗舜菁 +1 位作者 周智明 俞海 《精细化工》 EI CAS CSCD 北大核心 2003年第2期119-122,共4页
1 甲基 3 正丙基 5 吡唑羧酸经硝酸 -浓硫酸硝化制得 1 甲基 3 正丙基 4 硝基 5 吡唑羧酸 ,收率 85 %;用氯化亚砜将其酰氯化制得 1 甲基 3 正丙基 4 硝基 5 吡唑羧酰氯 ,该吡唑羧酰氯与浓氨水反应制得 1 甲基 3 正丙基 4 ... 1 甲基 3 正丙基 5 吡唑羧酸经硝酸 -浓硫酸硝化制得 1 甲基 3 正丙基 4 硝基 5 吡唑羧酸 ,收率 85 %;用氯化亚砜将其酰氯化制得 1 甲基 3 正丙基 4 硝基 5 吡唑羧酰氯 ,该吡唑羧酰氯与浓氨水反应制得 1 甲基 3 正丙基 4 硝基 5 吡唑羧酰胺 ,收率 90 %;硝基吡唑羧酰胺在乙醇中用氯化亚锡还原制得 1 甲基 3 正丙基 4 氨基 5 吡唑羧酰胺 ,收率 84%。研究了反应的较佳合成工艺条件 ,产品经TLC、IR及MS谱进行了结构表征。 展开更多
关键词 1-甲基-3-正丙基-4-氨基-5-吡唑羧酰胺 制备 1-甲基-3-正丙基-4-硝基-5-吡唑羧酸 1-甲基-3-正丙基-4-硝基-5-吡唑羧酰胺
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5-(色酮基-3-次甲基)(硫代)巴比妥酸的合成 被引量:4
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作者 解正峰 刘晨江 惠永海 《有机化学》 SCIE CAS CSCD 北大核心 2004年第10期1278-1280,共3页
将巴比妥酸或硫代巴比妥酸、3 甲酰基色酮在乙酸 -乙酸酐溶液 (含乙酸酐 10 % )中进行缩合反应 ,制备了 5 (色酮基 3 次甲基 ) (硫代 )巴比妥酸 .并经元素分析 ,IR ,1HNMR及13
关键词 5-(色酮基-3-次甲基)巴比妥酸 合成 缩合反应 3-甲酰基色酮 5-(色酮基-3-次甲基)硫代巴比妥酸
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Study on the Total Synthesis of 3-Oxo-9β-Acetoxyilicic Acid─The Synthesis of 9β-Acetoxy-3(4),11(13)-Dien-5αH,7αH-12-Eudesmanoic Acid Methyl Ester
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作者 Jiong YANG Zbao Ming XIONG Yong Gang CREN and Yu Lin LI(National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry,ho University, Lanzhou 730000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,共2页
The synthesis of 99-acetoxy-3(4), 11(13)-dien-5αH 7αH-12-eudesmanoic acid methyl ester (2) was achieved from oxycarvone. The key step is the p-toluenesulfonhydrazide assisted reductiv rearrangement reaction
关键词 The Synthesis of 9 H 7 H-12-Eudesmanoic acid Methyl Ester Dien-5 Study on the Total Synthesis of 3-Oxo-9 Acetoxyilicic acid Acetoxy-3
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3,4,5-三甲氧基氯苄的正交优化合成 被引量:1
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作者 彭彩云 陈文明 +4 位作者 盛文兵 张耿 肖浩 姚丽丽 匡朝 《中国医药导报》 CAS 2011年第2期29-30,共2页
目的:优化合成3,4,5-三甲氧基氯苄的方法。方法:以四氢呋喃为溶剂,3,4,5-三甲氧基苯甲酸在ZnCl2/NaBH4还原体系中制备3,4,5-三甲氧基苄醇,并经正交设计优化合成工艺研究,醇经氯化反应得到3,4,5-三甲氧基氯苄。结果:经过IR、1H-NMR分析,... 目的:优化合成3,4,5-三甲氧基氯苄的方法。方法:以四氢呋喃为溶剂,3,4,5-三甲氧基苯甲酸在ZnCl2/NaBH4还原体系中制备3,4,5-三甲氧基苄醇,并经正交设计优化合成工艺研究,醇经氯化反应得到3,4,5-三甲氧基氯苄。结果:经过IR、1H-NMR分析,证明产物是3,4,5-三甲氧基氯苄。结论:该工艺可以较高产率地合成3,4,5-三甲氧基氯苄,并且条件温和。 展开更多
关键词 3 4 5-三甲氧基氯苄 3 4 5-三甲氧基苯甲酸 3 4 5-三甲氧基苯甲醇 ZnCl2/NaBH4体系 正交优化 合成
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18种观赏植物F3′5′H基因生物信息学分析 被引量:1
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作者 曾慧兰 高阳 卢毅 《安徽农业科学》 CAS 2023年第7期103-109,共7页
采用生物信息学方法对18种观赏植物类黄酮-3′5′-羟化酶基因(flavonoid-3′5′-hydroxylase,F3′5′H)的mRNA和氨基酸序列的理化性质、跨膜结构域、保守结构域、亚细胞定位、二级结构、三级结构和同源性进行预测与分析。结果表明,绝大... 采用生物信息学方法对18种观赏植物类黄酮-3′5′-羟化酶基因(flavonoid-3′5′-hydroxylase,F3′5′H)的mRNA和氨基酸序列的理化性质、跨膜结构域、保守结构域、亚细胞定位、二级结构、三级结构和同源性进行预测与分析。结果表明,绝大多数观赏植物的F3′5′H为亲水性稳定蛋白质,以α螺旋为主、无信号肽的跨膜蛋白质;大多数定位于内质网膜上;其三级结构模型为5ylw.1.A铁锈醇合成酶,为单链蛋白,属于细胞色素P450基因家族;同源保守氨基酸序列为“LPPGP”“AGTDTS”和“PFGAGRRICAG”。 展开更多
关键词 生物信息学 观赏植物 氨基酸序列 类黄酮-35′-羟化酶
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5-氯-1-氧代-2,3-二氢茚-2-甲酸甲酯的合成研究 被引量:1
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作者 郭湘立 高中良 +1 位作者 刘英浪 李静 《河北工业大学学报》 CAS 北大核心 2012年第6期60-63,共4页
5-氯-1-氧代-2,3-二氢茚-2-甲酸甲酯(Ⅲ)是合成高效低毒杀虫剂茚虫威的关键中间体.本文对Ⅲ的合成方法进行了改进,以氯苯为起始原料,在无水三氯化铝催化下,与3-氯丙酰氯发生傅克酰基化反应制得3,4'-二氯苯丙酮(Ⅰ),Ⅰ在浓硫酸作用... 5-氯-1-氧代-2,3-二氢茚-2-甲酸甲酯(Ⅲ)是合成高效低毒杀虫剂茚虫威的关键中间体.本文对Ⅲ的合成方法进行了改进,以氯苯为起始原料,在无水三氯化铝催化下,与3-氯丙酰氯发生傅克酰基化反应制得3,4'-二氯苯丙酮(Ⅰ),Ⅰ在浓硫酸作用下环合制得5-氯-2,3-二氢-1-茚酮(Ⅱ),Ⅱ与氢化钠和碳酸二甲酯缩合制得Ⅲ,总收率53%.其化学结构通过1HNMR得到确证.Ⅱ的不加入惰性溶剂方法减小了反应釜体积,降低了设备成本.Ⅲ采用重结晶提纯方法相比柱色谱分离更适合工业化生产. 展开更多
关键词 3-氯丙酰氯 3 4'-二氯苯丙酮 5-氯-2 3-二氢-1-茚酮 5-氯-1-氧代-2 3-二氢茚-2-甲酸甲酯 合成
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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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新方法合成6-N-羟基吡咯并[3,4-b]吡嗪-5,7-二酮
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作者 於孝牛 钱春香 蔡琥 《化学试剂》 CAS CSCD 北大核心 2013年第4期373-375,共3页
以吡嗪-2,3-二羧酸为起始原料合成2,3-吡嗪二酸酐,在过量盐酸羟胺和无水碳酸钠溶液中反应得到3-羧基-2-吡嗪羟肟酸,再与氯化亚砜回流反应得到标题化合物,收率68%,其结构经IR、1HNMR和13CNMR确证。
关键词 2 3-吡嗪二酸酐 3-羧基-2-吡嗪羟肟酸 6-N-羟基吡咯并[3 4-b]吡嗪-5 7-二酮 合成
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Δ4-3-oxosteroid-5β-reductase deficiency: Responses to oral bile acid therapy and long-term outcomes 被引量:7
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作者 Mei-Hong Zhang Kenneth DR Setchell +3 位作者 Jing Zhao Jing-Yu Gong Yi Lu Jian-She Wang 《World Journal of Gastroenterology》 SCIE CAS 2019年第7期859-869,共11页
BACKGROUND Disorders of primary bile acid synthesis may be life-threatening if undiagnosed,or not treated with primary bile acid replacement therapy. To date, there are few reports on the management and follow-up of p... BACKGROUND Disorders of primary bile acid synthesis may be life-threatening if undiagnosed,or not treated with primary bile acid replacement therapy. To date, there are few reports on the management and follow-up of patients with Δ4-3-oxosteroid 5β-reductase(AKR1 D1) deficiency. We hypothesized that a retrospective analysis of the responses to oral bile acid replacement therapy with chenodeoxycholic acid(CDCA) in patients with this bile acid synthesis disorder will increase our understanding of the disease progression and permit evaluation of this treatment regimen as an alternative to the Food and Drug Administration(FDA) approved drug cholic acid, which is currently unavailable in China.AIM To evaluate the therapeutic responses of patients with AKR1 D1 deficiency to oral bile acid therapy, specifically CDCA.METHODS Twelve patients with AKR1 D1 deficiency, confirmed by fast atom bombardment ionization-mass spectrometry analysis of urine and by gene sequencing for mutations in AKR1 D1, were treated with differing doses of CDCA or ursodeoxycholic acid(UDCA). The clinical and biochemical responses to therapy were monitored over a period ranging 0.5-6.4 years. Dose adjustment, to optimize the therapeutic dose, was based on changes in serum biochemistry parameters,notably liver function tests, and suppression of the urinary levels of atypical hepatotoxic 3-oxo-Δ4-bile acids measured by mass spectrometry.RESULTS Physical examination, serum biochemistry parameters, and sonographic findings improved in all 12 patients during bile acid therapy, except one who underwent liver transplantation. Urine bile acid analysis confirmed a significant reduction in atypical hepatotoxic 3-oxo-Δ4 bile acids concomitant with clinical and biochemical improvements in those patients treated with CDCA. UDCA was ineffective in down-regulating endogenous bile acid synthesis as evidenced from the inability to suppress the urinary excretion of atypical 3-oxo-Δ4-bile acids. The dose of CDCA required for optimal clinical and biochemical responses varied from 5.5-10 mg/kg per day among patients based on maximum suppression of the atypical bile acids and improvement in serum biochemistry parameters, and careful titration of the dose was necessary to avoid side effects from CDCA.CONCLUSION The primary bile acid CDCA is effective in treating AKR1 D1 deficiency but the therapeutic dose requires individualized optimization. UDCA is not recommended for long-term management. 展开更多
关键词 Δ4-3-oxosteroid-5β-reductase DEFICIENCY Mass SPECTROMETRY BILE acid synthesis DISORDER Chenodeoxycholic acid Ursodeoxycholic acid
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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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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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