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Pesquisa : H01.181.404 [Categoria DeCS]
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  1 / 4556 MEDLINE  
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[PMID]:29367488
[Au] Autor:Autthanit C; Jongsomjit B
[Ad] Endereço:Center of Excellence on Catalysis and Catalytic Reaction Engineering, Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University.
[Ti] Título:Production of Ethylene through Ethanol Dehydration on SBA-15 Catalysts Synthesized by Sol-gel and One-step Hydrothermal Methods.
[So] Source:J Oleo Sci;67(2):235-243, 2018 Feb 01.
[Is] ISSN:1347-3352
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:The present work deals with the catalytic performance of SBA-15 supported catalysts in the gas phase catalytic dehydration of ethanol in the temperature range of 200 to 400°C. The SBA-15 support was incorporated on a zirconium (Zr) and bimetal of zirconium and lanthanum (Zr-La) prepared by sol-gel (SG) and hydrothermal (HT) methods. The catalysts were characterized by means of N physisorption, SEM/EDX, and NH -TPD. The experimental results demonstrated that the Zr-La/SBA-15-HT exhibited the highest catalytic activity. Ethanol conversion and ethylene selectivity were found to increase with increased reaction temperature. The best catalytic results were achieved for Zr-La/SBA-15-HT indicating values of ethanol conversion and ethylene yield of ca. 84% and 80%, respectively at 400°C. The most important parameter influencing their catalytic properties appears to be the interaction between metal and support depending on different methods. The metal dispersion inside the siliceous matrix of SBA-15 has a direct influence on their surface acidity. Meanwhile, the performance of these SBA-15 supported catalysts in ethanol dehydration is also related with the alteration of surface acidity caused by the introduction of Zr and Zr-La.
[Mh] Termos MeSH primário: Química Orgânica/métodos
Etanol/química
Etilenos/síntese química
Dióxido de Silício/química
[Mh] Termos MeSH secundário: Catálise
Dessecação
Lantânio/química
Temperatura Ambiente
Zircônio/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ethylenes); 0 (SBA-15); 3K9958V90M (Ethanol); 6I3K30563S (Lanthanum); 7631-86-9 (Silicon Dioxide); 91GW059KN7 (ethylene); C6V6S92N3C (Zirconium)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180126
[St] Status:MEDLINE
[do] DOI:10.5650/jos.ess17167


  2 / 4556 MEDLINE  
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[PMID]:29311461
[Au] Autor:Nambu H
[Ad] Endereço:Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama.
[Ti] Título:[Novel Methods for the Synthesis of Heterocycles Using Highly Reactive Spirocyclopropanes].
[So] Source:Yakugaku Zasshi;138(1):19-25, 2018.
[Is] ISSN:1347-5231
[Cp] País de publicação:Japan
[La] Idioma:jpn
[Ab] Resumo:This review describes our recent efforts to develop efficient methods for the synthesis of heterocyclic compounds, such as indoles and benzofurans, employing ring-opening cyclization of cyclohexane-1,3-dione-2-spirocyclopropanes, which were prepared by the reaction of 1,3-cyclohexanediones with sulfonium salts. Ring-opening cyclization of cyclohexane-1,3-dione-2-spirocyclopropanes with primary amines proceeded at room temperature to provide 2-substituted tetrahydroindol-4(5H)-ones in good to excellent yield. The obtained product was readily converted into a 2-substituted 4-hydroxyindole derivative. Furthermore, acid-catalyzed ring-opening cyclization of cyclohexane-1,3-dione-2-spirocyclopropanes proceeded smoothly at room temperature to provide 2-substituted tetrahydrobenzofuran-4(2H)-ones in excellent yield. The obtained product was converted into a 2-substituted 4-hydroxybenzofuran derivative. The synthetic utility of this catalytic protocol was demonstrated by the total synthesis of cuspidan B.
[Mh] Termos MeSH primário: Química Orgânica/métodos
Compostos Heterocíclicos/síntese química
[Mh] Termos MeSH secundário: Aminas/química
Benzofuranos/síntese química
Catálise
Ciclização
Cicloexanos/síntese química
Cicloexanonas/química
Ciclopropanos/síntese química
Indóis/síntese química
Fenômenos de Química Orgânica
Alimentos de Soja
Estilbenos/síntese química
Compostos de Sulfônio/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Amines); 0 (Benzofurans); 0 (Cyclohexanes); 0 (Cyclohexanones); 0 (Cyclopropanes); 0 (Heterocyclic Compounds); 0 (Indoles); 0 (Stilbenes); 0 (Sulfonium Compounds); 0 (cuspidan B); 6UK3D2BXJT (1,3-cyclohexanedione)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180110
[St] Status:MEDLINE
[do] DOI:10.1248/yakushi.17-00188


  3 / 4556 MEDLINE  
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[PMID]:29311462
[Au] Autor:Takagi A
[Ad] Endereço:Graduate School of Pharmaceutical Sciences, Osaka University.
[Ti] Título:[Development of Efficient Methods for Benzyne Generation].
[So] Source:Yakugaku Zasshi;138(1):27-35, 2018.
[Is] ISSN:1347-5231
[Cp] País de publicação:Japan
[La] Idioma:jpn
[Ab] Resumo:2-[(Neopentyl glycolato)boryl]phenyl triflates, readily synthesized from 2-iodophenol derivatives via halogen-magnesium exchange or Miyaura borylation, were developed as new benzyne precursors. Benzynes were generated under fluoride-ion-mediated conditions and reacted immediately with various arynophiles. Herein, we describe the generation of benzynes having reactive functional groups, such as methoxycarbonyl, acetyl, bromo, and amino groups, as well as their [4+2], (3+2), and [2+2] cycloaddition reactions which produce corresponding benzo-fused compounds.
[Mh] Termos MeSH primário: Derivados de Benzeno/síntese química
Química Orgânica/métodos
[Mh] Termos MeSH secundário: Reação de Cicloadição
Fluoretos
Halogênios/química
Iodobenzenos/química
Íons
Magnésio/química
Fenômenos de Química Orgânica
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Benzene Derivatives); 0 (Halogens); 0 (Iodobenzenes); 0 (Ions); 0 (benzyne); F27L34A8B9 (2-iodophenol); I38ZP9992A (Magnesium); Q80VPU408O (Fluorides)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180110
[St] Status:MEDLINE
[do] DOI:10.1248/yakushi.17-00157


  4 / 4556 MEDLINE  
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[PMID]:29199256
[Au] Autor:Saito N
[Ad] Endereço:Graduate School of Pharmaceutical Sciences, Tohoku University.
[Ti] Título:[Synthesis, Aggregation, Self-assembly, and Dynamic Properties of Helicene Oligomers].
[So] Source:Yakugaku Zasshi;137(12):1483-1490, 2017.
[Is] ISSN:1347-5231
[Cp] País de publicação:Japan
[La] Idioma:jpn
[Ab] Resumo:Biological systems exhibit dynamic phenomena at the macroscopic level as a result of the hierarchical integration of phenomena at the molecular level. For example, a number of amino acids compose actin proteins, which form three-dimensional structures determined by the sequence of amino acids. They form fibers by self-assembly, which then form ordered structures such as meshes, lyotropic liquid crystals (LCs), and bundles. The dynamic and reversible polymorphism between these nano- to centimeter-sized ordered structures is essential for biological functions such as cell division, contraction, and locomotion. To understand biological systems and create new functional materials, it is essential to develop a methodology to integrate phenomena at the molecular level into those at the macroscopic level using synthetic molecules. In this research, synthetic oligomers containing helicenes, which exhibit reversible structural transitions between cylindrical double helices and random coils in response to thermal stimuli, were employed as building blocks for the development of such a methodology. The properties of homo- and hetero-double helices at the molecular level were first controlled by taking advantage of the diversity of their molecular structures. Then, nano- to micrometer-sized structures were constructed by the self-assembly of hetero-double helices, which include fibers/gels, vesicles, and lyotropic LCs, and their dynamic properties were controlled by molecular design.
[Mh] Termos MeSH primário: Fenômenos Biológicos
Compostos Policíclicos
[Mh] Termos MeSH secundário: Animais
Disciplinas das Ciências Biológicas
Biopolímeros
Fenômenos Fisiológicos Celulares
Química Orgânica
Sequências Hélice-Alça-Hélice
Seres Humanos
Biologia Molecular
Estrutura Molecular
Nanopartículas
Compostos Policíclicos/química
Compostos Policíclicos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Biopolymers); 0 (Polycyclic Compounds); 0 (helicenes)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180112
[Lr] Data última revisão:
180112
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171205
[St] Status:MEDLINE
[do] DOI:10.1248/yakushi.17-00130


  5 / 4556 MEDLINE  
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[PMID]:28748936
[Au] Autor:Thompson SK; Hoye TR
[Ad] Endereço:Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA.
[Ti] Título:Organic chemistry: Molecular structure assignment simplified.
[So] Source:Nature;547(7664):410-411, 2017 07 26.
[Is] ISSN:1476-4687
[Cp] País de publicação:England
[La] Idioma:eng
[Mh] Termos MeSH primário: Química Orgânica
[Mh] Termos MeSH secundário: Estrutura Molecular
[Pt] Tipo de publicação:NEWS; COMMENT
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171128
[Lr] Data última revisão:
171128
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170728
[St] Status:MEDLINE
[do] DOI:10.1038/547410a


  6 / 4556 MEDLINE  
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[PMID]:28906494
[Au] Autor:Dallinger D; Kappe CO
[Ad] Endereço:Institute of Chemistry, University of Graz, NAWI Graz, Graz, Austria.
[Ti] Título:Lab-scale production of anhydrous diazomethane using membrane separation technology.
[So] Source:Nat Protoc;12(10):2138-2147, 2017 Oct.
[Is] ISSN:1750-2799
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Diazomethane is among the most versatile and useful reagents for introducing methyl or methylene groups in organic synthesis. However, because of its explosive nature, its generation and purification by distillation are accompanied by a certain safety risk. This protocol describes how to construct a configurationally simple tube-in-flask reactor for the in situ on-demand generation of anhydrous diazomethane using membrane separation technology and thus avoiding distillation methods. The described reactor can be prepared from commercially available parts within ∼1 h. In this system, solutions of Diazald and aqueous potassium hydroxide are continuously pumped into a spiral of membrane tubing, and diazomethane is generated upon mixing of the two streams. Pure diazomethane gas diffuses out of the reaction mixture through the membrane tubing (made of gas-permeable Teflon AF-2400). As the membrane tubing is immersed in a flask filled with the substrate solution, diazomethane is instantly consumed, which minimizes the risk of diazomethane accumulation. For this protocol, the reaction of diazomethane with benzoic acid on a 5-mmol scale has been selected as a model reaction and is described in detail. Methyl benzoate was isolated in an 88-90% yield (597-611 mg) within ∼3 h.
[Mh] Termos MeSH primário: Técnicas de Química Sintética/instrumentação
Técnicas de Química Sintética/métodos
Diazometano/química
Diazometano/isolamento & purificação
Membranas Artificiais
[Mh] Termos MeSH secundário: Química Orgânica
Diazometano/análise
Diazometano/metabolismo
Desenho de Equipamento
Politetrafluoretileno/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Membranes, Artificial); 60A625P70P (Diazomethane); 9002-84-0 (Polytetrafluoroethylene)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170925
[Lr] Data última revisão:
170925
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170915
[St] Status:MEDLINE
[do] DOI:10.1038/nprot.2017.046


  7 / 4556 MEDLINE  
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[PMID]:28406205
[Au] Autor:Mathew T
[Ad] Endereço:Loker Hydrocarbon Research Institute at the University of Southern California in Los Angeles, California, USA. He joined George Olah's group in 1996 and remained a close associate in the years afterwards.
[Ti] Título:George Andrew Olah (1927-2017).
[So] Source:Nature;544(7649):162, 2017 04 12.
[Is] ISSN:1476-4687
[Cp] País de publicação:England
[La] Idioma:eng
[Mh] Termos MeSH primário: Química Orgânica/história
[Mh] Termos MeSH secundário: Canadá
Dióxido de Carbono/química
Evolução Química
Química Verde/história
História do Século XX
Hungria
Los Angeles
Metanol/síntese química
Metanol/química
Prêmio Nobel
[Pt] Tipo de publicação:BIOGRAPHY; HISTORICAL ARTICLE; JOURNAL ARTICLE; PORTRAITS
[Ps] Nome de pessoa como assunto:Olah GA
[Nm] Nome de substância:
142M471B3J (Carbon Dioxide); Y4S76JWI15 (Methanol)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170822
[Lr] Data última revisão:
170822
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170414
[St] Status:MEDLINE
[do] DOI:10.1038/544162a


  8 / 4556 MEDLINE  
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[PMID]:28257120
[Au] Autor:Lenardão EJ; Borges EL; Stach G; Soares LK; Alves D; Schumacher RF; Bagnoli L; Marini F; Perin G
[Ad] Endereço:Laboratório de Síntese Orgânica Limpa (LASOL), Centrop de Ciências Químicas, Farmacêuticas e de Alimentos (CCQFA), Universidade Federal de Pelotas (UFPel), P.O. Box 354, 96010-900 Pelotas, RS, Brazil. lenardao@ufpel.edu.br.
[Ti] Título:Glycerol as Precursor of Organoselanyl and Organotellanyl Alkynes.
[So] Source:Molecules;22(3), 2017 Mar 02.
[Is] ISSN:1420-3049
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Herein we describe the synthesis of organoselanyl and organotellanyl alkynes by the addition of lithium alkynylchalcogenolate (Se and Te) to tosyl solketal, easily obtained from glycerol. The alkynylchalcogenolate anions were generated in situ and added to tosyl solketal in short reaction times, furnishing in all cases the respective products of substitution in good yields. Some of the prepared compounds were deprotected using an acidic resin to afford new water-soluble 3-organotellanylpropane-1,2-diols. The synthetic versatility of the new chalcogenyl alkynes was demonstrated in the iodocyclization of 2,2-dimethyl-1,3-dioxolanylmethyl(2-methoxyphenylethynyl)selane , which afforded 3-iodo-2-(2,2-dimethyl-1,3-dioxolanylmethyl) selenanylbenzo[ ]furan in 85% yield, opening a new way to access water-soluble Se-functionalized benzo[ ]furanes.
[Mh] Termos MeSH primário: Alquinos/química
Glicerol/química
Compostos Organometálicos/química
Compostos Organosselênicos/química
[Mh] Termos MeSH secundário: Química Orgânica
Fenômenos de Química Orgânica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alkynes); 0 (Organometallic Compounds); 0 (Organoselenium Compounds); PDC6A3C0OX (Glycerol)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170518
[Lr] Data última revisão:
170518
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170304
[St] Status:MEDLINE


  9 / 4556 MEDLINE  
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[PMID]:28250322
[Au] Autor:Itoh Y; Suzuki T
[Ad] Endereço:Graduate School of Medical Science, Kyoto Prefectural University of Medicine.
[Ti] Título:"Drug" Discovery with the Help of Organic Chemistry.
[So] Source:Yakugaku Zasshi;137(3):283-292, 2017.
[Is] ISSN:1347-5231
[Cp] País de publicação:Japan
[La] Idioma:jpn
[Ab] Resumo:The first step in "drug" discovery is to find compounds binding to a potential drug target. In modern medicinal chemistry, the screening of a chemical library, structure-based drug design, and ligand-based drug design, or a combination of these methods, are generally used for identifying the desired compounds. However, they do not necessarily lead to success and there is no infallible method for drug discovery. Therefore, it is important to explore medicinal chemistry based on not only the conventional methods but also new ideas. So far, we have found various compounds as drug candidates. In these studies, some strategies based on organic chemistry have allowed us to find drug candidates, through 1) construction of a focused library using organic reactions and 2) rational design of enzyme inhibitors based on chemical reactions catalyzed by the target enzyme. Medicinal chemistry based on organic chemical reactions could be expected to supplement the conventional methods. In this review, we present drug discovery with the help of organic chemistry showing examples of our explorative studies on histone deacetylase inhibitors and lysine-specific demethylase 1 inhibitors.
[Mh] Termos MeSH primário: Química Orgânica
Descoberta de Drogas/métodos
Descoberta de Drogas/tendências
[Mh] Termos MeSH secundário: Inibidores Enzimáticos
Inibidores de Histona Desacetilases
Histona Desmetilases/antagonistas & inibidores
Fenômenos de Química Orgânica
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Enzyme Inhibitors); 0 (Histone Deacetylase Inhibitors); EC 1.14.11.- (Histone Demethylases); EC 1.5.- (KDM1A protein, human)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:171016
[Lr] Data última revisão:
171016
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170303
[St] Status:MEDLINE
[do] DOI:10.1248/yakushi.16-00231-1


  10 / 4556 MEDLINE  
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[PMID]:28208825
[Au] Autor:Han YF; Yuan YX; Wang HB
[Ad] Endereço:Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education, School of Chemical and Environmental Engineering, Jianghan University, Wuhan 430056, Hubei, China. 15200828166@163.com.
[Ti] Título:Porous Hydrogen-Bonded Organic Frameworks.
[So] Source:Molecules;22(2), 2017 Feb 13.
[Is] ISSN:1420-3049
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Ordered porous solid-state architectures constructed via non-covalent supramolecular self-assembly have attracted increasing interest due to their unique advantages and potential applications. Porous metal-coordination organic frameworks (MOFs) are generated by the assembly of metal coordination centers and organic linkers. Compared to MOFs, porous hydrogen-bonded organic frameworks (HOFs) are readily purified and recovered via simple recrystallization. However, due to lacking of sufficiently ability to orientate self-aggregation of building motifs in predictable manners, rational design and preparation of porous HOFs are still challenging. Herein, we summarize recent developments about porous HOFs and attempt to gain deeper insights into the design strategies of basic building motifs.
[Mh] Termos MeSH primário: Química Orgânica
Ligações de Hidrogênio
Hidrogênio/química
Fenômenos de Química Orgânica
[Mh] Termos MeSH secundário: Modelos Químicos
Modelos Moleculares
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
7YNJ3PO35Z (Hydrogen)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170509
[Lr] Data última revisão:
170509
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170218
[St] Status:MEDLINE



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