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CF_(3)H和CO_(2)抑制CH_(4)爆炸实验研究
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作者 白洁琪 白纪成 +3 位作者 梁运涛 王琳 宋双林 田富超 《煤矿安全》 CAS 北大核心 2024年第5期122-130,共9页
为对比研究CF_(3)H和CO_(2)对CH_(4)爆炸特性的抑制效果,使用20 L球型爆炸压力测试系统分别测量对比2种抑制剂对CH_(4)在空气中爆炸极限范围的影响;研究了不同体积分数的2种抑制剂对CH_(4)体积分数9.5%爆炸压力参数影响,分析了2种抑制... 为对比研究CF_(3)H和CO_(2)对CH_(4)爆炸特性的抑制效果,使用20 L球型爆炸压力测试系统分别测量对比2种抑制剂对CH_(4)在空气中爆炸极限范围的影响;研究了不同体积分数的2种抑制剂对CH_(4)体积分数9.5%爆炸压力参数影响,分析了2种抑制剂针对CH_(4)在空气中爆炸的爆炸三角形。结果表明:CF_(3)H和CO_(2)均能缩小CH_(4)在空气中的爆炸极限范围,抑制CH_(4)至失爆所需CF_(3)H和CO_(2)体积分数分别为12.5%和21.5%;对比抑制CH_(4)体积分数9.5%的爆炸参数(反应峰值压力和升压速率),10%CF_(3)H的抑爆能力是等量CO_(2)的1.95倍和1.3倍,但是低于体积分数4%的CF_(3)H单独使用时对CH_(4)爆炸存在微弱的促进作用;2种抑制剂作用下的爆炸三角形显示CF_(3)H抑制下的可爆区域面积小于CO_(2),安全区域内CF_(3)H的窒息比是CO_(2)的57%。 展开更多
关键词 Ch_(4)爆炸 瓦斯爆炸 CO_(2) CF_(3)h 爆炸极限 抑爆剂 爆炸压力 爆炸三角形
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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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微生物合成4-羟基-2,5-二甲基-3(2H)-呋喃酮的研究进展
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作者 宋金鹏 仲秀芳 +3 位作者 李学思 曹振华 彭新辉 范光森 《中国酿造》 CAS 北大核心 2024年第4期14-21,共8页
4-羟基-2,5-二甲基-3(2H)-呋喃酮(HDMF)是一种具有焦糖味的安全优良的甜味香料和增香剂,其阈值低、香势好且特征性强,被广泛应用于食品、烟草等产品中,市场需求量大,尤其是天然来源的HDMF受到人们更多的青睐。然而,天然来源的HDMF产量较... 4-羟基-2,5-二甲基-3(2H)-呋喃酮(HDMF)是一种具有焦糖味的安全优良的甜味香料和增香剂,其阈值低、香势好且特征性强,被广泛应用于食品、烟草等产品中,市场需求量大,尤其是天然来源的HDMF受到人们更多的青睐。然而,天然来源的HDMF产量较低,尚不能满足当前市场的需求。该文从其应用、检测、生产方法、合成HDMF微生物的种类、微生物合成HDMF的机制与关键酶及其发酵培养影响因素进行简述,重点侧重于已报道的具有合成HDMF的微生物种类、微生物合成HDMF的内在机制及其影响其发酵的培养因素,旨在为后续筛选、改造获得优良高产HDMF微生物菌株,并优化微生物发酵条件实现生物法高效制备天然HDMF提供参考。 展开更多
关键词 4-羟基-2 5-二甲基-3(2h)-呋喃酮 微生物合成 合成机制 培养条件
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可见光下g-C_(3)N_(4)催化诱导C(sp^(2))-H芳基化喹喔啉-2(1H)-酮 被引量:1
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作者 赵能选 李兰杰 +1 位作者 徐宏烈 王涛 《化学研究与应用》 CAS 北大核心 2024年第2期299-305,共7页
建立了一种有效且简单的可见光诱导的g-C_(3)N_(4)催化的喹喔啉-2(1H)-酮的芳基化反应。该反应以乙腈为溶剂,K_(2)S_(2)O_(8)为氧化剂,具有反应条件温和、环境友好和官能团耐受性好等优点。该策略提供了一种简单的操作方法,可以获得各... 建立了一种有效且简单的可见光诱导的g-C_(3)N_(4)催化的喹喔啉-2(1H)-酮的芳基化反应。该反应以乙腈为溶剂,K_(2)S_(2)O_(8)为氧化剂,具有反应条件温和、环境友好和官能团耐受性好等优点。该策略提供了一种简单的操作方法,可以获得各种中等到良好产率的3-苯基喹喔啉-2(1H)-酮化合物,最高产率达77%。 展开更多
关键词 光催化 3-苯基喹喔啉-2(1h)-酮 g-C_(3)N_(4)
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IDH2 and GLUD1 depletion arrests embryonic development through an H4K20me3 epigenetic barrier in porcine parthenogenetic embryos
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作者 Cheng-Lin Zhan Qin-Yue Lu +7 位作者 Song-Hee Lee Xiao-Han Li Ji-Dam Kim Gyu-Hyun Lee Jae-Min Sim Hyeon-Ji Song Ying-Yan Jin Xiang-Shun Cui 《Zoological Research》 SCIE CSCD 2024年第6期1175-1187,共13页
Isocitrate dehydrogenase 2(IDH2)and glutamate dehydrogenase 1(GLUD1)are key enzymes involved in the production ofα-ketoglutarate(α-KG),a metabolite central to the tricarboxylic acid cycle and glutamine metabolism.In... Isocitrate dehydrogenase 2(IDH2)and glutamate dehydrogenase 1(GLUD1)are key enzymes involved in the production ofα-ketoglutarate(α-KG),a metabolite central to the tricarboxylic acid cycle and glutamine metabolism.In this study,we investigated the impact of IDH2 and GLUD1 on early porcine embryonic development following IDH2 and GLUD1 knockdown(KD)via doublestranded RNA(dsRNA)microinjection.Results showed that KD reducedα-KG levels,leading to delayed embryonic development,decreased blastocyst formation,increased apoptosis,reduced blastomere proliferation,and pluripotency.Additionally,IDH2 and GLUD1 KD induced abnormally high levels of trimethylation of lysine 20 of histone H4(H4K20me3)at the 4-cell stage,likely resulting in transcriptional repression of embryonic genome activation(EGA)-related genes.Notably,KD of lysine methyltransferase 5C(KMT5C)and supplementation with exogenousα-KG reduced H4K20me3 expression and partially rescued these defects,suggesting a critical role of IDH2 and GLUD1 in the epigenetic regulation and proper development of porcine embryos.Overall,this study highlights the significance of IDH2 and GLUD1 in maintaining normal embryonic development through their influence onα-KG production and subsequent epigenetic modifications. 展开更多
关键词 A-ketoglutarate h4K20me3 IDh2 GLUD1 Embryonic development
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New 4-imino-4H-Chromeno[2,3-d]Pyrimidin-3(5H)-Amine: Synthesis, Cytotoxic Effects on Tumoral Cell Lines and in Silico ADMET Properties
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作者 Marwa Dhiabi Sirine Karoui +7 位作者 Mehdi Fakhfakh Souhir Abid Emmanuelle Limanton Rémy Le Guével Thierry Charlier Ludovic Paquin Jean-Pierre Bazureau Houcine Ammar 《International Journal of Organic Chemistry》 2024年第3期107-122,共16页
The synthesis of new 4-imino-4H-chromeno[2,3-d]pyrimidin-3(5H)-amine in four steps including one step under microwave dielectric heating is reported. The structural identity of the synthesized compounds was establishe... The synthesis of new 4-imino-4H-chromeno[2,3-d]pyrimidin-3(5H)-amine in four steps including one step under microwave dielectric heating is reported. The structural identity of the synthesized compounds was established according to their spectroscopic analysis, such as FT-IR, NMR and mass spectroscopy. These new compounds were tested for their antiproliferative activities on seven representative human tumoral cell lines (Huh7 D12, Caco2, MDA-MB231, MDA-MB468, HCT116, PC3 and MCF7) and also on fibroblasts. Among them, only the compounds 6c showed micromolar cytotoxic activity on tumor cell lines (1.8 50 50 > 25 μM). Finally, in silico ADMET studies ware performed to investigate the possibility of using of the identified compound 6c as potential anti-tumor compound. 展开更多
关键词 2-Amino-4h-Chromene 4h-Chromeno[2 3-d]Pyrimidin-3(5h)-Amine Microwave Irradiation Tumoral Cell Line in Silico ADMET
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一种改善糖尿病肾病的新型化合物3-(3,4-二羟基苯基)-2(1H)-喹喔啉酮
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作者 陈欢 黄旭虎 《山东化工》 CAS 2024年第20期76-79,共4页
目的:糖尿病肾病(Diabetes nephropathy,DN)是导致终末期肾病的主要原因,也是糖尿病最顽固的并发症之一。活性氧(reactive oxygen species,ROS)累积导致的氧化应激促进DN的发展,因此,清除ROS是预防和治疗DN的关键方法。方法:制备了3-芳... 目的:糖尿病肾病(Diabetes nephropathy,DN)是导致终末期肾病的主要原因,也是糖尿病最顽固的并发症之一。活性氧(reactive oxygen species,ROS)累积导致的氧化应激促进DN的发展,因此,清除ROS是预防和治疗DN的关键方法。方法:制备了3-芳基喹喔啉酮衍生物。通过测量糖尿病模型鼠的尿蛋白水平、丙二醛(Malondialdehyde,MDA)水平和肾脏谷胱甘肽(Glutathione,GSH)水平,测定该化合物DN病症改善效果。结果:3-(3,4-二羟基苯基)-2(1H)-喹喔啉酮可降低小鼠的尿蛋白、MDA水平,增加肾脏GSH水平,证实其显著的抗氧化作用,改善蛋白尿,降低氧化应激水平,缓解糖尿病肾病病理症状。结论:以上结果表明该化合物在改善DN引起的肾损伤中具有潜在作用。 展开更多
关键词 糖尿病肾病 3-(3 4-二羟基苯基)-2(1h)-喹喔啉酮 抗氧化剂
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Synthesis, Crystal Structure and Antitumor Activity of 2-(3-Methyl-5-(methylthio)-4H-1,2,4-triazol-4-yl)isoindoline-1,3-dione 被引量:6
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作者 赵培亮 胡孟金 +2 位作者 段安娜 孙晓敏 游文玮 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第3期359-364,共6页
The title compound 2-(3-methyl-5-(methylthio)-4H-1,2,4-triazol-4-yl)isoindoline- 1,3-dione (C12H10NaO2S, Mr= 274.30) has been synthesized by a three-step procedure including the cyclization, hydrazinolysis and s... The title compound 2-(3-methyl-5-(methylthio)-4H-1,2,4-triazol-4-yl)isoindoline- 1,3-dione (C12H10NaO2S, Mr= 274.30) has been synthesized by a three-step procedure including the cyclization, hydrazinolysis and substitution reactions, and its crystal structure was determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P2/c with a = 12.264(3), b = 14.646(3), c = 14.349(4) A,β = 91.69(3)°,μ = 0.255 mm1, Mr = 274.30, V = 2576.2(10) A3, Z =8, Dc = 1.414 g/cm3, F(000) = 1136, R = 0.0487 and wR = 0.1329 for 4048 observed reflections with I 〉 2σ(I). In addition, the preliminary bioassay suggested that the title compound 6 exhibits relatively good antitumor activity against HT-29 and MCF-7. 展开更多
关键词 2-(3-methyl-5-(methylthio)-4h-1 2 4-triazol-4-yl)isoindoline-l 3-dione synthesis
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Differential protein expression in substantia nigra induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine in a mouse model of chronic Parkinson’s disease 被引量:2
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作者 Wenbin Tu Furong Xu Guoguang Peng 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第5期482-485,共4页
BACKGROUND: To date, a complete protein expression profile of the midbrain substantia nigra in a mouse model of chronic Parkinson's disease, induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP), does ... BACKGROUND: To date, a complete protein expression profile of the midbrain substantia nigra in a mouse model of chronic Parkinson's disease, induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP), does not exist. In addition, there are no reports of analysis of differential protein expression. OBJECTIVE: To separate and evaluate MPTP-induced differential protein expression through the use of proteomics in the substantia nigra of a mouse model of chronic Parkinson's disease. DESIGN: Randomized controlled animal study. SETTING: Department of Neurology, the First Affiliated Hospital, Chongqing Medical University. MATERIALS: Sixteen 8-10-week old, healthy, male, C57BL mice, weighing 20-25 g, and of clean grade, were provided by the Experimental Animal Center of Chongqing Medical University. The experimental animals were disposed according to ethical criteria. MPTP was provided by Sigma Company, USA; Pdquest 2D image analysis software and gelatum/irradiance image analysis system (ChemiDoc XRS) by Bio-Rad, USA; and Voyager DE-PROMALD1-TOF-MS mass spectroscopy analyzer by AB1 Company, USA. METHODS: This study was performed in Chongqing Neurological Laboratory between November 2006 and July 2007. Mice were randomly divided into model and control groups, with 8 mice in each group. Mice in the model group were received a subcutaneous injection of MPTP (25 mg&g), twice a week, for five successive weeks, to establish a chronic Parkinson's disease model. Mice in the control group received the same volume of a subcutaneous saline injection at the same time points. Mice were sacrificed by anesthesia to rapidly obtain the midbrain for protein separation of the substantia nigra. MAIN OUTCOME MEASURES: (1) 2-ED handbook (Bio-Rad Company) was referenced for two-dimensional electrophoresis, (2) PDQUEST8,0 analytical electrophoresis pattern was adopted to evaluate differential protein expression. (3) Peptide mass finger print map and data were retrieved on http://www.prospector.ucsf.edu to compare differential substantia nigral protein expression in the two groups. RESULTS: Two-dimensional gel electrophoresis of substantia nigra tissue indicated that there were 33 differential protein expressions between the two groups. Three new proteins were evaluated, including α -enolase, which exhibited regulated expression, tumor necrosis factor ligand superfamily member 4, and cyclin-dependent kinase inhibitor 1B. CONCLUSION: There are three proteins that exhibit differential expression in the substantia nigra- α -enolase, tumor necrosis factor ligand superfamily member 4, and cyclin-dependent kinase inhibitor 1B. 展开更多
关键词 Parkinson's disease 1-methyl-4-phenyl-l 2 3 6-tetrahydropyridine mice substantia nigra proteomics
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Synthesis of fused pyran and arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methane in ionic liquid 被引量:2
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作者 Xue Sen Fan Ying Ying Qu Xin Ying Zhang Xia Wang Jian Ji Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第4期387-390,共4页
Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3- yl)methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-... Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3- yl)methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-methyl-2-oxo-pyran with or without acetic anhydride. By using these novel procedures, pyrimidine nucleoside-fused pyran and arylbis(pyranon-3-yl)methane hybrids with potential biological activities were constructed. 展开更多
关键词 Ionic liquid Fused pyran Arylbis(4-hydroxy-6-methyl-2-oxo-2h-pyran-3-yl)methane Pyrimidine nucleoside Green synthesis
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Synthesis and Crystal Structure of Trans-4-[(5-(2,4-Dichlorophenoxy)-3-methyl-1-phenyl-1H-pyrazol-4-yl)methyleneamino]-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 被引量:4
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作者 孙凤梅 田孟魁 +1 位作者 杨靖华 连照勋 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第7期789-792,共4页
The title compound trans-4-[(5-(2,4-dichlorophenoxy)-3-methyl- 1-phenyl-1H-pyrazol-4-yl)methyleneamino]- 1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 3 (C28H23Cl2N5O2, Mr = 532.41) has been synthesized and its... The title compound trans-4-[(5-(2,4-dichlorophenoxy)-3-methyl- 1-phenyl-1H-pyrazol-4-yl)methyleneamino]- 1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 3 (C28H23Cl2N5O2, Mr = 532.41) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in triclinic, space group P1- with a = 8.9438(4), b = 11.6065(5), c = 14.2215(6)A, α = 112.566(1), β = 92.324(2), γ = 102.91(1)°, V= 1315.65(10) A^3, Z = 2, Dc = 1.344 g/cm^3,μ(MoKa) = 0.282 mm^-1, λ = 0.71073 A, F(000) = 552, the final R = 0.0587 and wR = 0.1578 for 5071 observed reflections (I 〉 2σ(I)). X-ray analysis reveals that the product is a thermodynamically stable trans isomer. Intra- and intermolecular C( 12)-H(12)…O(1) and C(28)-H(28)...O(1)# 1 hydrogen bonds were observed in the title compound. 展开更多
关键词 trans-4-[ 5-(2 4-dichlorophenoxy)-3-methyl- 1-phenyl- 1h-pyrazol-4-yl)methylene amino]-1 5-dimethyl-2-phenyl-1 2-dihydropyrazol-3-one synthesis crystal structure
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Synthesis and Crystal Structure of Ethyl 3-(4-Chlorophenyl)-3,4-dihydro-6-methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate 被引量:2
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作者 胡扬根 徐靖 丁明武 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第6期689-692,共4页
The crystal structure of the title compound ethyl 3-(4-chlorophenyl)-3,4-dihydro-6- methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate (C20H20ClN3O4, Mr= 401.84) has been prepared and determined... The crystal structure of the title compound ethyl 3-(4-chlorophenyl)-3,4-dihydro-6- methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate (C20H20ClN3O4, Mr= 401.84) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 20.6215(9), b = 8.5311(4), c = 21.6886(9) A^°, β = 91.607(1)°, V = 3814.0(3)A^°^3, Z = 8, Dc = 1.400 g/cm^3, F(000) = 1680, μ = 0.233 mm^-1, R = 0.0718 and wR = 0.1545 for 6717 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals two crystallographically independent molecules in the asymmetric unit. 展开更多
关键词 crystal structure ethyl 3-(4-ehlorophenyl)-3 4-dihydro-6-methyl-4-oxo-2- (pyrrolidin-1-yl)furo[2 3-d]pyrimidine-5-earboxylate aza-Wittig reaction synthesis
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Synthesis and Crystal Structure of 2-Ethoxycarbonylmethyl-8-chloro-3a,4-dihydro-3a-methyl-chromeno[4,3-c]pyrazol-3(2H)-one 被引量:1
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作者 赵培亮 周中振 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第8期1280-1283,共4页
The crystal structure of the title compound 2-ethoxycarbonylmethyl-8-chloro-3a,4-dihydro-3a-methyl-chromeno[4,3-c]pyrazol-3(2H)-one(C15H15ClN2O4,Mr = 322.74) has been prepared and determined by single-crystal X-ra... The crystal structure of the title compound 2-ethoxycarbonylmethyl-8-chloro-3a,4-dihydro-3a-methyl-chromeno[4,3-c]pyrazol-3(2H)-one(C15H15ClN2O4,Mr = 322.74) has been prepared and determined by single-crystal X-ray diffraction.The crystal is of orthorhombic,space group Pccn with a = 16.7246(10),b = 19.6626(12),c = 9.3013(6) ,V = 3058.7(3) 3,Z = 8,Dc = 1.402 g/cm3,μ = 0.269 mm-1,F(000) = 1344,the final R = 0.0506 and wR = 0.1464 for 2568 reflections with I 〉 2σ(I).In addition,disordered C(14) and C(15) atoms exist in the crystal structure. 展开更多
关键词 chromeno[4 3-c]pyrazol-32h)-one SYNThESIS insecticidal activity crystal structure structural disorder
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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 ZHOU Zhong-Zhen YOU Wen-Wei ZHAO Pei-Liang 《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 system,spac... 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)Å,α=64.770(2),β=75.720(2),γ=89.784(2)°,μ=0.085 mm^(-1),Mr=442.49,V=1174.1(2)Å3,Z=2,Dc=1.252 g/cm^(3),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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H_4SiW_(12)O_(40)/SiO_2催化一锅法合成4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮 被引量:9
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作者 龚文朋 向诗银 +1 位作者 徐玉林 杨水金 《精细化工》 EI CAS CSCD 北大核心 2014年第2期225-228,254,共5页
采用一锅法Biginelli反应以H4SiW12O40/SiO2为催化剂,以苯甲醛、乙酰乙酸乙酯和尿素为原料,无水乙醇为溶剂合成了4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮。探讨了原料摩尔比、反应温度、催化剂用量及反应时间对收率的影响。结... 采用一锅法Biginelli反应以H4SiW12O40/SiO2为催化剂,以苯甲醛、乙酰乙酸乙酯和尿素为原料,无水乙醇为溶剂合成了4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮。探讨了原料摩尔比、反应温度、催化剂用量及反应时间对收率的影响。结果表明,固定苯甲醛用量为0.04 mol的条件下,n(苯甲醛)∶n(乙酰乙酸乙酯)∶n(尿素)=1∶1.5∶1.5,催化剂的用量占反应物料总质量的2.0%,反应温度为90℃,反应时间为60 min,产品平均收率可达71.7%。通过熔点的测定,IR,1HNMR和MS对合成的3,4-二氢嘧啶酮化合物进行了表征。 展开更多
关键词 h4SiW12O40 SIO2 3 4-二氢嘧啶酮 BIGINELLI反应 一锅法 医药与日化原料
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应用Ca^(2+)荧光探针fluo-3和fluo-4测定H_2O_2诱导的A549细胞凋亡过程中的[Ca^(2+)]_i变化 被引量:7
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作者 张四洋 李春艳 +2 位作者 高建 邱雪杉 崔泽实 《中国肺癌杂志》 CAS 北大核心 2014年第3期197-202,共6页
背景与目的肺癌是世界范围内常见的恶性肿瘤,Ca2+对于肿瘤细胞凋亡有重要的调控作用。实时监测肺癌细胞内Ca2+水平,有助于深入研究Ca2+介导肺癌细胞凋亡的分子机制。本研究旨在观察Ca2+荧光探针fluo-3和fluo-4在H2O2诱导的A549细胞凋亡... 背景与目的肺癌是世界范围内常见的恶性肿瘤,Ca2+对于肿瘤细胞凋亡有重要的调控作用。实时监测肺癌细胞内Ca2+水平,有助于深入研究Ca2+介导肺癌细胞凋亡的分子机制。本研究旨在观察Ca2+荧光探针fluo-3和fluo-4在H2O2诱导的A549细胞凋亡过程中的应用,实时测定胞浆Ca2+浓度([Ca2+]i),探讨[Ca2+]i与细胞凋亡的关系,并比较两种Ca2+探针在荧光强度及[Ca2+]i测定值方面的差异。方法采用Ca2+荧光探针fluo-3和fluo-4负载细胞,1 h后用不同浓度的H2O2刺激细胞,激光扫描共聚焦显微镜实时测定选取细胞的[Ca2+]i变化。采用DAPI染色试剂盒观察H2O2刺激后细胞凋亡情况。结果在相同的探针浓度、负载时间和相同的图像采集参数的条件下,选定细胞内fluo-4平均荧光强度高于fluo-3。50 mM H2O2刺激后,A549细胞胞浆内[Ca2+]i迅速升高,通过公式计算发现采用fluo-3探针负载的选定细胞中[Ca2+]i变化范围是112.2 nM-1,069.6 nM,采用fluo-4探针负载的选定细胞中[Ca2+]i变化范围是7.6nM-505.4 nM。同时发现经H2O2刺激后,凋亡细胞百分比明显增加(P<0.01)。结论 H2O2促进A549细胞内Ca2+释放,诱导细胞凋亡。Ca2+探针fluo-4可能更适合于监测含量较低的细胞中[Ca2+]i变化。 展开更多
关键词 Fluo-3 Fluo-4 CA^2+ h2O2 细胞凋亡
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C_4H_8N_2H_4·Zn(HPO_3)_2的水热合成和结构表征 被引量:6
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作者 史苏华 李光华 +6 位作者 辛明红 李悦明 丁红 徐家宁 朱广山 宋天佑 裘世纶 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2004年第2期230-232,共3页
A new zinc hydrogen phosphite C4H8N2H4·Zn(HPO3)2 was prepared by hydrothermal method in the presence of piperazine as a structure-directing agent and the crystal structure was determined by single-crystal X-ray... A new zinc hydrogen phosphite C4H8N2H4·Zn(HPO3)2 was prepared by hydrothermal method in the presence of piperazine as a structure-directing agent and the crystal structure was determined by single-crystal X-ray diffraction analysis and further characterized by X-ray powder diffraction, IR, ICP, elemental analysis and TG analysis. This compound has one-dimensional anionic chains containing four-membered rings built from corner-sharing linked alternating ZnO4 tetrahedra and HPO3 pseudo pyramids. The zinc hydrogen phosphite chains are interacted with the templates of diprotonated piperazine by N—H…O hydrogen bond. Crystal data for C4H8N2H4·Zn(HPO3)2∶monoclinic, space group C2/c. a=1.774 8(2) nm, b=0.724 28(9) nm, c=0.880 87(11) nm, β= 105.345(3)°, V=1.091 9(2) nm 3, Z=4, Dc=1^907 Mg/m 3, R1=0.022 9, wR2=0.058 8. 展开更多
关键词 C4h8N2h4·Zn(hPO3)2 水热合成 结构表征 亚磷酸锌 哌嗪 单晶结构 有机模板
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苯酚-KBrO_3-H_2SO_4振荡体系的诱导期与周期 被引量:11
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作者 高执棣 于宝庆 +1 位作者 刘君利 林秋竹 《物理化学学报》 SCIE CAS CSCD 北大核心 1989年第2期214-217,共4页
1978年,Orbán和Koros简略碰报导了苯酚-KBrO_3-H_2SO_4体系的振荡行为。直到现在,该体系详细的实验研究未见报导。近来,我们对此体系的振荡行为重新作了探讨,发现与前人的结果大不相同,具有独特的规律。实验方法与文献[2]的完全相... 1978年,Orbán和Koros简略碰报导了苯酚-KBrO_3-H_2SO_4体系的振荡行为。直到现在,该体系详细的实验研究未见报导。近来,我们对此体系的振荡行为重新作了探讨,发现与前人的结果大不相同,具有独特的规律。实验方法与文献[2]的完全相同。所用的药品,苯酚为A.R.级,KBrO_3和H_2SO_4均为G.R.级。实验温度为298±0.5K。今将所得结果报导如下。 展开更多
关键词 苯酚 KBRO3 h2SO4 振荡体系
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层状K_4Ag_2Sn_3S_9·2H_2O的溶剂热合成与表征 被引量:10
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作者 白音孟和 纪敏 +3 位作者 刘新 安永林 贾翠英 宁桂铃 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2004年第8期1391-1394,M003,共5页
用溶剂热法合成了 K4 Ag2 Sn3S9· 2 H2 O,通过单晶 X射线衍射、 DSC、 TG、 IR和紫外漫反射光谱等手段对其进行了表征 .结果表明 ,K4 Ag2 Sn3S9· 2 H2 O属单斜晶系 ,P2 1 / m空间群 ,a=0 .780 71 ( 2 ) nm,b=2 .73 5 0 8( 1 )... 用溶剂热法合成了 K4 Ag2 Sn3S9· 2 H2 O,通过单晶 X射线衍射、 DSC、 TG、 IR和紫外漫反射光谱等手段对其进行了表征 .结果表明 ,K4 Ag2 Sn3S9· 2 H2 O属单斜晶系 ,P2 1 / m空间群 ,a=0 .780 71 ( 2 ) nm,b=2 .73 5 0 8( 1 ) nm,c=1 .0 5 0 0 8nm,α=90°,β=1 0 3 .87( 6)°,γ=90°,Z=4.其层状结构内具有一维孔道 。 展开更多
关键词 溶剂热合成 K4Ag2Sn3S9·2h2O 层状结构
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MgSO_4·5Mg(OH)_2·3H_2O的水热合成及反应时间对其形貌的影响(英文) 被引量:18
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作者 朱黎霞 岳涛 +1 位作者 高世杨 夏树屏 《无机化学学报》 SCIE CAS CSCD 北大核心 2003年第1期99-102,共4页
Both whisker and nanometer MgSO4·5Mg(OH)2·3H2O(MOS) were prepared by hydrothermal method at 140℃for different times, using NaOH and MgSO4·7H2O as raw materials. The MgSO4·5Mg(OH)2·3H2O part i... Both whisker and nanometer MgSO4·5Mg(OH)2·3H2O(MOS) were prepared by hydrothermal method at 140℃for different times, using NaOH and MgSO4·7H2O as raw materials. The MgSO4·5Mg(OH)2·3H2O part icles were characterized by powder X ray diffraction(XRD),thermal analysis(TGA DSC), infrared spectroscopy(FT IR),transmission electron microscopy(SEM) and scanning electron microscopy(TEM). The size distribution in whisker like and nanocrystalline materials arein the range of 10~50μm and 10~20nm respectively. The whisker MOS is metastable phase in MgSO4 NaOH H2O system at 140℃,whereas nanometer MOS is stable phase. 展开更多
关键词 MgSO4·5Mg(Oh)2·3h2O 水热合成 反应时间 形貌 硫氧镁
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