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An environmentally friendly synthesis of 1,4-dihydropyrano[2,3-c]pyrazole derivatives catalyzed by tungstate sulfuric acid 被引量:2
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作者 Mahnaz Farahi Bahador Karami +1 位作者 Iman Sedighimehr Hamideh Mohamadi Tanuraghaj 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第12期1580-1582,共3页
An efficient three-component synthesis of 6-amino-4-aryl-5-cyano-3-metriyl-1-phenyl-1,4-dihydropyrano[2,3-c]pyrazoles via a reaction between 3-methyl-1-phenyl-2-pyrazolin-5-one,aromatic aldehydes and malononitrile usi... An efficient three-component synthesis of 6-amino-4-aryl-5-cyano-3-metriyl-1-phenyl-1,4-dihydropyrano[2,3-c]pyrazoles via a reaction between 3-methyl-1-phenyl-2-pyrazolin-5-one,aromatic aldehydes and malononitrile using tungstate sulfuric acid as a catalyst was described.Mild conditions,good to excellent yields,easily available catalyst and easy work-up are the key features of this method. 展开更多
关键词 6-Amino-4-aryl-5-cyano-3-methyl-1phenyl-1 4-dihydropyrano[2.3-c]pyrazoles 3-Methyl-1-phenyl-2-pyrazolin-5-one Aromatic aldehyde Malononitrile Tungstate sulfuric acid
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Synthesis and anti-TMV activity of novel N-(3-alkyl-1H-pyrazol-4-yl)-3-alkyl-4-substituted-1H-pyrazole-5-carboxamides 被引量:3
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作者 Da Qiang Zhang Gao Fei Xu +3 位作者 Zhi Jin Fan Dao Quan Wang Xin Ling Yang De Kai Yuan 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第6期669-672,共4页
In order to investigate the biological activity of novel bis-pyrazole compounds, a series of N-(3-alkyl-5-(N-methylcarbamyl)- 1H-pyrazol-4-yl)-3-alkyl-4-substituted-lH-pyrazole-5-carboxamides were designed and syn... In order to investigate the biological activity of novel bis-pyrazole compounds, a series of N-(3-alkyl-5-(N-methylcarbamyl)- 1H-pyrazol-4-yl)-3-alkyl-4-substituted-lH-pyrazole-5-carboxamides were designed and synthesized with ethyl 3-alkyl-lH-pyr- azole-5-carboxylate 1 as starting materials. N-Methyl-3-alkyl-4-amino-lH-pyrazole-5-carboxamides 6 were obtained from 1 via 5 steps. 3-Alkyl-4-substitued-lH-pyrazole-5-carboxyl chlorides 4a, 4b, lla, llb, llc or 12 were also obtained from 1 via several steps. Target compounds 7a-Tg were obtained after the reaction of 6 with the above 1H-pyrazole-5-carboxyl chlorides. Preliminary bioassay showed some compounds possessing good inactivation effect against TMV (tobacco mosaic virus). Compound 7a showed higher activity superior to ningnanmycin at a concentration of 5.0 × 10^-4 g/mE and equal activity at 1.0 × 10^-4 g/mE; 7b and 7c showed equal activity to virazole both at concentrations of 5.0 × 10^-4 g/mE and 1.0 × 10^-4 g/mL. 展开更多
关键词 Bis-pyrazole compounds 3-Alkyl-4-amino-lH-pyrazole-5-carboxamides 3-Alkyl-lH-pyrazole-5-carboxyl chlorides Inactivationeffect TMV
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Efficient synthesis of 4-substituted pyrazole via microwave-promoted Suzuki cross-coupling reaction 被引量:1
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作者 Hua Cheng Qiong-You Wu +1 位作者 Fan Han Guang-Fu Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第5期705-709,共5页
Pyrazoles and their derivatives are important heterocycles found in nature and present in numerous bioactive compounds.In contrast to 3 or 5-aryl pyrazole,the preparation of 4-aryl pyrazole is fairly rare.Utilizing mi... Pyrazoles and their derivatives are important heterocycles found in nature and present in numerous bioactive compounds.In contrast to 3 or 5-aryl pyrazole,the preparation of 4-aryl pyrazole is fairly rare.Utilizing microwave irradiation,the synthesis of 4-substituted-arylpyrazole via Suzuki cross-coupling has been developed with a wide range of substrates.The remarkable advantages of this method are mild reaction conditions,simple operation,high yield,and short reaction time.Product structures were identified by MS 1H NMR 13C NMR,and elemental analysis. 展开更多
关键词 4-Aryl pyrazoles Suzuki cross-coupling reactions 4-Iodo-1-methyl-1H-pyrazole Microwave irradiation
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Design, synthesis and insecticidal activities of novel 1-substituted-5-(trifluoromethyl)-1H-pyrazole-4-carboxamide derivatives 被引量:1
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作者 Zhi-Bing Wu Xiang Zhou +2 位作者 Yi-Qiang Ye Pei-Yi Wang Song Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第1期121-125,共5页
A series of novel 5-(trifluoromethyl)-1H-pyrazole-4-carboxamide derivatives(6a–6n, 7a, 7b, and 8a-8f)were synthesised by placing the amide bond at the 4-position of the pyrazole ring. These derivatives differed f... A series of novel 5-(trifluoromethyl)-1H-pyrazole-4-carboxamide derivatives(6a–6n, 7a, 7b, and 8a-8f)were synthesised by placing the amide bond at the 4-position of the pyrazole ring. These derivatives differed from the structure of chlorantraniliprole analogues with the amide bond at the 5-position of the pyrazole ring. Preliminary bioassay results revealed that a few title compounds exhibited good insecticidal activities against lepidopteran pests, such as Plutella xylostella, Mythimna separate, Heliothis armigera, and Ostrinia nubilalis. Some title compounds also elicited broad-spectrum insecticidal activities against dipterous insects including Culex pipiens pallens after altering the amide position. Similar to pyrazole-5-carboxamide analogues, compounds 6b and 6e showed 100% insecticidal activity against P. xylostella, C. pipiens pallens, and M. separate at concentrations of 200, 2, and 200 mg/m L, respectively.This finding suggested that 5-(trifluoromethyl)-1H-pyrazole-4-carboxamide derivatives are potential alternative insecticides for management of agriculture pests. 展开更多
关键词 5-(Trifluoromethyl )- 1H-pyrazole-4-carboxamide Insecticidal activities Chlorantraniliprole Ryanodine receptors
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Synthesis and Crystal Structure of a Novel Ethyl 5-(4-(2-Phenylacetamido)phenyl)-1H-pyrazole-3-carboxylate as an Acrosin Inhibitor 被引量:2
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作者 祁晶晶 周有骏 +5 位作者 刘雪飞 丁莉莉 郑灿辉 盛春泉 吕加国 朱驹 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第11期1604-1608,共5页
The title compound (ethyl5-(4-(2-phenylacetamido)phenyl)-lH-pyrazole-3-carboxylate, C20H19N3O3) was synthesized by the reaction of Claisen condensation, cyclization, reduction and acylation. The structure was ch... The title compound (ethyl5-(4-(2-phenylacetamido)phenyl)-lH-pyrazole-3-carboxylate, C20H19N3O3) was synthesized by the reaction of Claisen condensation, cyclization, reduction and acylation. The structure was characterized by X-ray diffraction, MS, NMR and IR. It belongs to the monoclinic system, space group C2/c with a = 22.723(9), b = 9.324(4), c = 18.890(8) A, β = 114.259(6)°, V = 3649(3) A^3, Dc = 1.272 Mg·m^3, Z = 8, Mr = 349.38, p = 0.087 mm^-1, F(000) = 1472, the final R = 0.0615 and wR = 0.1643. The biological test shows that the title compound has a moderate acrosin inhibition activity. 展开更多
关键词 ethyl 5-(4-(2-phenylacetamido)phenyl)-1H-pyrazole-3-carboxylate crystal structure acrosin inhibitor
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Silica-Grafted Ionic Liquids as Recyclable Catalysts for the Synthesis of 3,4-Dihydropyrano[c]chromenes and Pyra-no[2,3-c]pyrazoles 被引量:1
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作者 Khodabakhsh Niknam Abolhassan Piran 《Green and Sustainable Chemistry》 2013年第2期1-8,共8页
Silica-grafted N-propyl-imidazolium hydrogen sulfate ([Sipim]HSO4) is employed as a recyclable heterogeneous ionic liquid catalyst for the synthesis of 3,4-dihydropyrano[c]-chromenes by the reaction of aromatic aldehy... Silica-grafted N-propyl-imidazolium hydrogen sulfate ([Sipim]HSO4) is employed as a recyclable heterogeneous ionic liquid catalyst for the synthesis of 3,4-dihydropyrano[c]-chromenes by the reaction of aromatic aldehydes, malononitrile and 4-hydroxycoumarin at 100°C under solvent-free conditions. Also, heterogeneous ionic liquid catalyst was used for the synthesis of pyrano[2,3-c]-pyrazoles by the reaction of aromatic aldehydes, malononitrile and 3-methyl-l-phenyl-5-pyrazolone at 110°C under solvent-free conditions. The heterogeneous ionic liquid showed much the same efficiency when used in consecutive reaction runs. 展开更多
关键词 Silica-Grafted N-Propyl-Imidazolium Hydrogen Sulfate Aldehydes Pyrano[2 3-c]-pyrazoles 3 4-Dihydropyrano[c]-chromenes Solvent-Free Heterogeneous Ionic Liquid Catalysts
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Syntheses,Structures,and Luminescent Properties of Zinc(Ⅱ)and Silver(Ⅰ)Complexes Based on 1-(4′-Carboxylatobenzyl)-3-(pyrazin-2-yl)pyrazole
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作者 杨明星 黄妹金 +2 位作者 黄美丽 杨秀红 林深 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第5期786-794,共9页
Two novel coordination compounds, [Zn(CBPP)2(H2O)2]·3H2O(1) and[Ag(CBPP)·2H2O](2)(HCBPP = 1-(4?-carboxylatobenzyl)-3-(pyrazin-2-yl)pyrazole), were hydrothermally synthesized and characterize... Two novel coordination compounds, [Zn(CBPP)2(H2O)2]·3H2O(1) and[Ag(CBPP)·2H2O](2)(HCBPP = 1-(4?-carboxylatobenzyl)-3-(pyrazin-2-yl)pyrazole), were hydrothermally synthesized and characterized. Compound 1 crystallizes in monoclinic, space group C2 with a = 26.221(4), b = 8.4211(7), c = 14.295(3)A, β = 114.561(8)°, V = 2705.9(2) A3, Dc = 1.587 g/cm3, C28H28Cl2N8O9 Zn, Mr = 685.97 F(000) = 1416, μ(Mo Kα) = 0.926 mm-1, Z = 4, R = 0.0287, w R = 0.1076 for 2818 observed reflections(I 〉 2σ(I)), and R = 0.0300, w R = 0.1110 for all data. In 1, each deprotonated CBPP-ligand with a bidentate coordination mode connects two Zn(II) atoms to generate a 1D helical chain along the b axis. The adjacent chains intersect with each other through hinged Zn(II) ions to build up an interesting two-dimensional network. Compound 2 crystallizes in monoclinic, space group P21/n with a = 6.3544(1), b = 11.7195(3), c = 19.3188(4)A, β = 94.297(2)°, V = 1434.64(5) A3, Dc = 1.894 g/cm3, C14H13 Ag N4O4, Mr = 409.15 F(000) = 816, μ(Mo Kα) = 11.536 mm-1, Z = 4, R = 0.0456 and w R = 0.1184 for 2402 observed reflections(I 〉 2σ(I)), and R = 0.0517, w R = 0.1275 for all data. In 2, each ligand binds two Ag(I) atoms in a tridentate coordination mode to form an infinite zigzag chain. Their thermal and photoluminescent properties were also investigated. 展开更多
关键词 coordination polymer fluorescence 4?-carboxylatobenzyl)-3-(pyrazin-2-yl)pyrazole ligand zinc(Ⅱ) silver(Ⅰ)
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Two New Schiff Bases Based on 5-Chloro-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde: Syntheses, Crystal Structures and Properties
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作者 SUN Feng-Mei HAN Qiong +4 位作者 JIANG Zheng-Jing ZHAO Pan-Xiang WANG Jia RUI Jia-Yi XU Ji-Ming 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第3期408-415,共8页
Two new Schiff bases based on 5-chloro-3-methyl-1-phenyl-1 H-pyrazole-4-carbaldehyde, namely, N-((5-chloro-3-methyl-1-phenyl-1 H-pyrazol-4-yl)methylene)-4-morpholinoaniline(Ⅲa) and N-((5-chloro-3-methyl-1-phenyl-1 H-... Two new Schiff bases based on 5-chloro-3-methyl-1-phenyl-1 H-pyrazole-4-carbaldehyde, namely, N-((5-chloro-3-methyl-1-phenyl-1 H-pyrazol-4-yl)methylene)-4-morpholinoaniline(Ⅲa) and N-((5-chloro-3-methyl-1-phenyl-1 H-pyrazol-4-yl)methylene)-3-fluoro-4-morpholinoaniline(Ⅲb), were synthesized and characterized by IR, LC-MS, 1 H NMR and 13 C NMR spectroscopy. Meanwhile, the three-dimensional configurations of the two title compounds were further characterized by single-crystal X-ray diffraction analyses. Both the compounds are thermodynamically stable trans-isomers. Moreover, the fluorescence properties and antioxidant activities against DPPH of the two target compounds have been investigated, and the results showed that the title compounds both have fluorescence performance and certain antioxidant activities against DPPH radical. 展开更多
关键词 Schiff base 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde synthesis CRYSTAL structure property
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Design and Synthesis of Novel Pyrazolo[3,4-c]pyrazol and Pyrrolo[2,3-c]pyrazol Derivatives as Potential BTK Inhibitors
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作者 ZHENG Nan PAN Jing +2 位作者 HAO Qun LIN Kuaile ZHOU Weicheng 《中国医药工业杂志》 CAS CSCD 北大核心 2018年第10期1361-1372,共12页
A novel series of pyrazolo[3,4-c]pyrazol and pyrrolo[2,3-c]pyrazol derivatives were designed,synthesized and biologically evaluated as potential Bruton's tyrosine kinase(BTK)inhibitors.Ten compounds exhibited vari... A novel series of pyrazolo[3,4-c]pyrazol and pyrrolo[2,3-c]pyrazol derivatives were designed,synthesized and biologically evaluated as potential Bruton's tyrosine kinase(BTK)inhibitors.Ten compounds exhibited variant inhibitory activities against BTK in vitro,and 8a showed the highest potency(IC50=127 nmol/L against BTK enzyme).The molecular docking of compound 8a was performed to understand the probable binding mode for this novel pyrazolo[3,4-c]pyrazol derivatives with BTK,which provided a comprehensive guide for further structural modification. 展开更多
关键词 BTK inhibitors pyrazolo[3 4-c]pyrazole pyrrolo[2 3-c]pyrazole molecular docking inhibitory activity
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Synthesis and Crystal Structure of 2(1-Phenyl-3-methyl-5-chloro-1H-pyrazol- 4-yl)-3-(1-naphthoylamido)-4-thiazolidinone 被引量:4
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作者 李明 文丽荣 +2 位作者 景淑霞 赵桂龙 杨华铮 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第4期366-370,共5页
The crystal structure of 2(1-phenyl-3-methyl-5-chloro-1H-pyrazol-4-yl)-3-(1- naphthoylamido)-4-thiazolidinone (C24H19ClN4O2S, Mr = 462.94) has been determined by single- crystal X-ray diffraction method. The crystal b... The crystal structure of 2(1-phenyl-3-methyl-5-chloro-1H-pyrazol-4-yl)-3-(1- naphthoylamido)-4-thiazolidinone (C24H19ClN4O2S, Mr = 462.94) has been determined by single- crystal X-ray diffraction method. The crystal belongs to monoclinic, space group P21/c with a = 11.623(5), b = 11.579(5), c = 16.619(7) ? b = 90.112(8), V = 2237(2) 3, Z = 4, Dc = 1.375 g/cm3, m = 0.294 mm-1, F(000) = 960, R = 0.0492 and wR = 0.0768 for 3932 unique reflections with 1897 observed ones (I > 2s(I)). X-ray analysis reveals that there exist both intra-and intermolecular hydrogen bonds in the crystal lattice. 展开更多
关键词 pyrazole 4-THIAZOLIDINONE crystal structure synthesis
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中空骨料对轻质MgO-MgAl_(2)O_(4)-C耐火材料力学性能的影响
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作者 黄科 殷超凡 +6 位作者 王黎 于仁红 董宾宾 臧云飞 梁艳晨 李满仓 秦峰 《耐火材料》 北大核心 2025年第1期38-44,共7页
为了有效降低内衬材料的热量损失,保持钢液温度稳定,以高纯电熔镁砂、自制镁铝尖晶石中空骨料、α-Al_(2)O_(3)微粉、镁铝尖晶石粉、Si粉、Al粉和鳞片石墨为主要原料,以热固性酚醛树脂为结合剂,经1 200℃和1 400℃埋碳热处理制备了MgO-M... 为了有效降低内衬材料的热量损失,保持钢液温度稳定,以高纯电熔镁砂、自制镁铝尖晶石中空骨料、α-Al_(2)O_(3)微粉、镁铝尖晶石粉、Si粉、Al粉和鳞片石墨为主要原料,以热固性酚醛树脂为结合剂,经1 200℃和1 400℃埋碳热处理制备了MgO-MgAl_(2)O_(4)-C耐火材料。探究了自制镁铝尖晶石中空骨料加入量(加入质量分数分别为0、3%、6%、9%)对轻质MgO-MgAl_(2)O_(4)-C耐火材料力学性能的影响。结果表明:经1 200℃热处理后试样中有SiC和AlN产生,升温至1 400℃时生成了片状MgAlON。随着镁铝尖晶石中空骨料加入量的增加,试样的显气孔率上升,体积密度下降。当热处理温度为1 400℃时,加入6%(w)镁铝尖晶石中空骨料试样的常温抗折强度和耐压强度均达到最大值,分别为14.8 MPa和121 MPa,抗折强度保持率高达80%。中空骨料的引入改变了应力分布方向,形成了不同的耗散机制,实现了对材料的增强增韧。 展开更多
关键词 MgO-MgAl_(2)O_(4)-c耐火材料 中空骨料 MgAl_(2)O_(4) 力学性能
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废旧锂电有价元素提取热处理炉用SiC-Si_(3)N_(4)-C质耐侵蚀材料研究
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作者 姜悦纳 叶欣健 +6 位作者 陶天一 杨梦瑶 林凡凯 郑晓洪 孙振华 吴小文 黄朝晖 《耐火材料》 北大核心 2025年第3期224-228,共5页
回收废旧锂电池有价元素常用火法结合湿法冶金回收工艺,为提高回收工艺中热处理炉衬材料的耐腐蚀性能,以用后铁水包砖细颗粒(1~0.5、≤0.5 mm)、碳化硅(2~1、1~0.5、<0.5 mm)、氮化硅(<0.045 mm)和石墨为原料,将用后铁水包砖细颗... 回收废旧锂电池有价元素常用火法结合湿法冶金回收工艺,为提高回收工艺中热处理炉衬材料的耐腐蚀性能,以用后铁水包砖细颗粒(1~0.5、≤0.5 mm)、碳化硅(2~1、1~0.5、<0.5 mm)、氮化硅(<0.045 mm)和石墨为原料,将用后铁水包砖细颗粒替代同等粒度的氮化硅经800~1400℃保温3 h制备SiC-Si_(3)N_(4)-C复相耐火材料。研究了用后铁水包砖细颗粒加入量(加入质量分数分别为0、12.12%、26.25%、36.38%和48.5%)和热处理温度(800、1000、1200、1400℃)对复相耐火材料性能的影响。结果表明:1)随着用后铁水包砖细颗粒加入量的增加,试样体积密度变化较小,显气孔率呈现出逐渐减小的趋势,常温耐压强度和常温抗折强度先减小后增大;2)随着热处理温度的增加,试样体积密度先增加后减小,显气孔率呈现出逐渐减小的趋势,常温耐压强度和常温抗折强度增加;3)当热处理温度为1400℃,用后铁水包砖细颗粒全部取代碳化硅细颗粒时,试样综合性能最佳,其体积密度、显气孔率、常温耐压强度和常温抗折强度分别为2.37 g·cm^(-3)、14.3%、31.6 MPa和9.0 MPa,且1000℃抗废旧锂电池破碎料侵蚀性能良好。 展开更多
关键词 废旧锂电池回收 热处理 SiC-Si_(3)N_(4)-c 用后铁水包砖 抗侵蚀性能
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Key Intermediates: A Simple and Highly Selective Synthesis of 5-<i>Amino</i>-1-<i>aryl</i>-1<i>H</i>-<i>pyrazole</i>-4-<i>carbonitriles</i>for Applications in the Crop Protection 被引量:11
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作者 Silvana C. Plem Diana M. Müller Marcelo C. Murguía 《Advances in Chemical Engineering and Science》 2015年第3期239-261,共23页
A series of six pyrazoles was synthesized by Michael-type addition reaction. The molecules 5-amino-1-aryl-1H-pyrazole-4-carbonitrile (3a-f) were synthesized from (ethoxymethylene)malo-nonitrile (1) and fluorinated and... A series of six pyrazoles was synthesized by Michael-type addition reaction. The molecules 5-amino-1-aryl-1H-pyrazole-4-carbonitrile (3a-f) were synthesized from (ethoxymethylene)malo-nonitrile (1) and fluorinated and non-fluorinated aryl hydrazines (2a-f) using ethanol and fluorinated ethanol as solvents at reflux. An excellent regio-selectivity was found when pyrazole derivatives were formed as an exclusive product. No other regioisomer or uncyclised hydrazide was observed. Their structures were confirmed by spectroscopy data (1H, 13C, 19F, COSY (correlation spectroscopy), HSQC (heteronuclear single-quantum correlation spectroscopy) and HMBC (heteronuclear multiple-bond correlation spectroscopy);MS (mass-spectrometry). The yields ranged from good to excellent (47% - 93%) under mild reaction conditions. It would indicate a high selectivity in the one-step work procedure. These products (3a-f) and derivatives have a potential academic and industrial use as key intermediates, in special, for application in crop protection. 展开更多
关键词 ARYL pyrazole ARYL HYDRAZINE AMINO pyrazole 5-Amino-1-aryl-1H-pyrazole-4-carbonitriles
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Morpholine triflate promoted one-pot,four-component synthesis of dihydropyrano[2,3-c]pyrazoles 被引量:3
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作者 Chen-Feng Zhou Jian-Jun Li Wei-Ke Su 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第11期1686-1690,共5页
A one-pot, four-component reaction of ethyl acetoacetate, hydrazine hydrate, aldehydes, and malononitrile was discussed using Lewis acid catalyst morpholine triflate (MorT) to afford a series of dihydropyrano[2,3-c]... A one-pot, four-component reaction of ethyl acetoacetate, hydrazine hydrate, aldehydes, and malononitrile was discussed using Lewis acid catalyst morpholine triflate (MorT) to afford a series of dihydropyrano[2,3-c]pyrazoles, which were generally catalyzed by organic alkalis. Moderate to excellent yields, no chromatographic purification, and evasion of environmentally hazardous solvents in the reaction process make this protocol very useful for academia and industry. 展开更多
关键词 Dihydropyrano[2 3-c]pyrazole MCRs Morpholine triflate Green chemistry Lewis acid
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Bovine serum albumin:An efficient and green biocatalyst for the one-pot four-component synthesis of pyrano[2,3-c]pyrazoles 被引量:1
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作者 Xingtian Huang Zhipeng Li +1 位作者 Dongyang Wang Yiqun Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第9期1461-1468,共8页
The use of biocatalysts is attracting an increasing amount of attention in chemical catalysis.Here,we have shown that bovine serum albumin(BSA),a ubiquitous,inexpensive,non-enzymatic transport protein,can serve as a... The use of biocatalysts is attracting an increasing amount of attention in chemical catalysis.Here,we have shown that bovine serum albumin(BSA),a ubiquitous,inexpensive,non-enzymatic transport protein,can serve as an efficient,retrievable catalyst in the one-pot four-component reaction of aryl aldehydes,malononitrile,hydrazine hydrate,and ethyl acetoacetate for the synthesis of pyrano[2,3-c]pyrazoles under mild reaction conditions.The BSA biocatalyst also displayed a high catalytic affinity for acyclic/cyclic ketones to yield the corresponding pyrano[2,3-c]pyrazoles or their spirocyclic variants.The BSA could be used for at least five cycles without serious loss of catalytic activity.This novel,efficient protocol has the merits of high yield,operational simplicity,and a relatively benign environmental impact.Moreover,the method extends the promiscuity of BSA as a biocatalyst. 展开更多
关键词 Bovine serum albumin BIOCATALYST Multicomponent reaction Pyrano[2 3-c]pyrazole Biocatalytic promiscuity
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L-Proline catalyzed one-pot multi-component synthesis of 2-(1,3-diphenyl-1H-pyrazol-4-yl)quinazolin-4(3H)-one derivatives and their biological studies 被引量:1
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作者 Hemal B. Mehta Bharat C. Dixit Ritu B. Dixit 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第5期741-744,共4页
A new series of quinazolin-4(3H)-one derivatives containing a(1 3-diphenyl-1H-pyrazol-4-yl) core with substituents at the 2-position and aromatic or heteroaromatic substituents at the 3-position were synthesized u... A new series of quinazolin-4(3H)-one derivatives containing a(1 3-diphenyl-1H-pyrazol-4-yl) core with substituents at the 2-position and aromatic or heteroaromatic substituents at the 3-position were synthesized using an L-proline catalyzed one-pot multi-component reaction approach.All the synthesized compounds were characterized and screened for their antimicrobial,antifungal and anti-tubercular activities. 展开更多
关键词 Quinazolin-4(3H)-one pyrazole L-Proline Antimicrobial Antifungal Anti-tubercular activity
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Synthesis and in vitro antimicrobial screening of new pyrano[4,3-b]pyrane derivatives of 1H-pyrazole 被引量:4
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作者 Chetan B.Sangani Divyesh C.Mungra +1 位作者 Manish P.Patel Ranjan G.Patel 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第1期57-60,共4页
A new series of pyrano[4,3-b]pyrane 4a-l bearing 1H-pyrazole has been synthesized by one pot base catalyzed cyclocondensation reaction of 1H-pyrazole-4-carbaldehyde la-1,malononitrile 2 and 4-hydroxy-6-methylpyrone 3.... A new series of pyrano[4,3-b]pyrane 4a-l bearing 1H-pyrazole has been synthesized by one pot base catalyzed cyclocondensation reaction of 1H-pyrazole-4-carbaldehyde la-1,malononitrile 2 and 4-hydroxy-6-methylpyrone 3.All the synthesized compounds were screened against six bacterial pathogens,namely B.subtilis,C.tetani,S.pneumoniae,S.typhi,V.cholerae, E.coli and antifungal activity against,two fungal pathogens,A.fumigatus and C.albicans using broth microdilution MIC method. Some of the compounds are found to be equipotent or more potent than that of commercial drugs,against most of employed strains. 展开更多
关键词 Pyranopyrane MCR pyrazole-4-carbaldehyde Antimicrobial activity
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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-3(2H)-one SYNTHESIS insecticidal activity crystal structure structural disorder
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A Novel Tandem Reaction for the Synthesis of Thieno[2,3-C] Pyrazole
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作者 Zhong Wen WANG Jun REN +1 位作者 Han Song CHEN Zheng Ming LI(State Key Laboratory of Elemento-organic Chemistry. Institute of Elemento-organic Chemistry.Nankai University Tianjin 300071) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第3期189-190,共2页
A new method was found for the synthesis of pyrazoleacetate esters from pyrazolaldehyde. By a new tandem reaction, in which methyl 4-pyrazoleacetate reacted with carbon disulfide and iodomethane, thieno[2,3-c] pyrazol... A new method was found for the synthesis of pyrazoleacetate esters from pyrazolaldehyde. By a new tandem reaction, in which methyl 4-pyrazoleacetate reacted with carbon disulfide and iodomethane, thieno[2,3-c] pyrazole was synthesized. This was an easy method for the synthesis of this type of heterocycles. 展开更多
关键词 thieno[2.3-c]pyrazole HETEROCYCLES SYNTHESIS
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Synthesis, Spectroscopy and Electrochemistry of New 3-(5-Aryl-4,5-Dihydro-1H-Pyrazol-3-yl)-4-Hydroxy-2H-Chromene-2-One 4, 5 as a Novel Class of Potential Antibacterial and Antioxidant Derivatives
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作者 Abdullah Sulaiman Al-Ayed 《International Journal of Organic Chemistry》 2011年第3期87-96,共10页
3-((2E)-3(aryl)prop-2-enoyl)-2H-chromen-2-one 3 was synthesized from 4-hydroxy coumarin by refluxing 3-acetyl-4-hydroxy coumarin with aromatic aldehydes in chloroform in the presence of a catalytic amount of piperidin... 3-((2E)-3(aryl)prop-2-enoyl)-2H-chromen-2-one 3 was synthesized from 4-hydroxy coumarin by refluxing 3-acetyl-4-hydroxy coumarin with aromatic aldehydes in chloroform in the presence of a catalytic amount of piperidine. 3 was converted to pyrazoles 4, 5 by treatment with hydrazine and phenylhydrazine in toluene, respectively. The structures of the new compounds were confirmed by elemental analysis, IR, and multinuclear/multidimensional NMR spectroscopy (1H, 13C-NMR, NOESY, HMBC) which allowed us to assign the complete network of proton and carbon atoms. All the compounds exhibited one quasireversible redox process. All the newly synthesized compounds were screened for their antibacterial and antioxidant activities. Antimicrobial studies revealed that 3-(5-(2,5-dimethylphenyl)-1-phenyl-4,5-dihydro-1H-pyrazol-3-yl)-4- hydroxy-2H-chromene-2-one 5c showed significant antibacterial activity against Escherichia coli and Pseudomonas Aeruginosa 27853. Furthermore, 3-(5-(aryl)-4,5-dihydro-1H-pyrazol-3-yl)-4-hydroxy-2H-chromene- 2-ones 4, 5 showed antioxidant activities of different extents with respect to individual compounds as well as to the antioxidant methods. The 3-(5-(phenyl)-4,5-dihydro-1H-pyrazol-3-yl)-4-hydroxy-2H-chromene-2-ones 4a was found to be the most active antioxidant in the series and more active than trolox which makes the investigated complexes a new promising class of antibacterial compounds. 展开更多
关键词 4-HYDROXYCOUMARIN pyrazole ANTIBACTERIAL ACTIVITY Antioxydant ACTIVITY
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