Base de dados : MEDLINE
Pesquisa : D02.092.877.674 [Categoria DeCS]
Referências encontradas : 2 [refinar]
Mostrando: 1 .. 2   no formato [Detalhado]

página 1 de 1

  1 / 2 MEDLINE  
              next record last record
para imprimir
[Au] Autor:Kikuchi T; Okamura T; Fukushi K; Irie T
[Ad] Endereço:Molecular Probe Group, Molecular Imaging Center, National Institute of Radiological Sciences, Japan.
[Ti] Título:Piperidine-4-methanthiol ester derivatives for a selective acetylcholinesterase assay.
[So] Source:Biol Pharm Bull;33(4):702-6, 2010.
[Is] ISSN:1347-5215
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:The activity of acetylcholinesterase (AChE) is measured to obtain pathological information about the cholinergic system in various disease states and to assess the effect of AChE inhibitors. Using Ellman's method that is commonly used in such examinations, butyrylcholinesterase inhibitors must be added to measure AChE-specific activity because of low selectivity of AChE toward traditional substrates; however, such inhibitors also inhibit AChE. Therefore, it is desirable to obtain an AChE selective substrate that can be used with the Ellman's method. Here, we synthesized novel AChE substrates, 1-methyl-4-acetylthiomethylpiperidine and 1,1-dimethyl-4-acetylthiomethylpiperidine, and evaluated the hydrolysis rate and AChE selectivity by comparison with the results obtained when traditional substrates were used. The hydrolysis rate of the novel compounds by human AChE was one order of magnitude lower than that of the traditional substrates, acetylthiocholine and acetyl-beta-methylthiocholine, whereas the hydrolysis rate using human butyrylcholinesterase was two orders of magnitude lower than that of the traditional substrates. This indicated that AChE showed selectivity towards the novel substrates which was one order of magnitude higher than that of the traditional substrates. The hydrolysis of the novel compounds in a rat cerebral cortical homogenate and a monkey whole blood was completely inhibited by 1 muM of the specific AChE inhibitor, 1,5-bis(4-allyldimethylammoniumphenyl)pentan-3-one, indicating the high specificity of AChE towards the novel substrates in a crude tissue sample. From these results, we conclude that the novel compounds developed would be suitable AChE-selective substrates for Ellman's method.
[Mh] Termos MeSH primário: Acetilcolinesterase/metabolismo
[Mh] Termos MeSH secundário: Animais
Córtex Cerebral/metabolismo
Inibidores da Colinesterase/farmacologia
Ácido Ditionitrobenzoico
Seres Humanos
Compostos de Fenilamônio
Piperidinas/síntese química
Ratos Wistar
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cholinesterase Inhibitors); 0 (Phenylammonium Compounds); 0 (Piperidines); 625-00-3 (Thiocholine); 9BZQ3U62JX (Dithionitrobenzoic Acid); EC (Acetylcholinesterase); EC (Butyrylcholinesterase)
[Em] Mês de entrada:1011
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:100423
[St] Status:MEDLINE

  2 / 2 MEDLINE  
              first record previous record
para imprimir
Texto completo
[Au] Autor:Lee DR; Galant NJ; Wang H; Mucsi Z; Setiadi DH; Viskolcz B; Csizmadia IG
[Ad] Endereço:Department of Chemistry, University of Toronto, Toronto, Ontario, Canada M5S 3H6.
[Ti] Título:Thermodynamic functions of molecular conformations of (2-fluoro-2-phenyl-1-ethyl)ammonium ion and (2-hydroxy-2-phenyl-1-ethyl)ammonium ion as models for protonated noradrenaline and adrenaline: first-principles computational study of conformations and thermodynamic functions for the noradrenaline and adrenaline models.
[So] Source:J Phys Chem A;113(11):2507-15, 2009 Mar 19.
[Is] ISSN:1520-5215
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:This paper reports the structural and thermodynamic consequences of substitution of the OH group by the isoelectronic F-atom in the case of the adrenaline family of molecules. The conformational landscapes were explored for the two enantiomeric forms of N-protonated-beta-fluoro-beta-phenyl-ethylamine, also called (2-fluoro-2-phenyl-1-ethyl)-ammonium ion (Model 1) and that of N-protonated-beta-hydroxy-beta-phenyl-ethylamine, also referred to as (2-hydroxy-2-phenyl-1-ethyl)-ammonium (Model 2) models of noradrenaline and adrenaline molecules. These full conformational studies were carried out by first principles of quantum mechanical computations at the B3LYP/6-31G(d,p) and G3MP2B3 levels of theory, using the Gaussian03 program. Also, frequency calculations of the stable structures were performed at the B3LYP/6-31G(d,p), and G3MP2B3 levels of theory. The thermodynamic functions (U, H, S, and G) of the various stable conformations of the title compounds were calculated at these levels of theory for the R and S stereoisomers. Relative values of the thermodynamic functions have been calculated with respect of the chosen reference conformers in which all relevant dihedral angles assumed anti orientation for the Model 1 and Model 2. Through the combination of both point and axis chirality, the enantiomeric and diastereomeric relationships of the six structures for each molecule investigated were established. Intramolecular hydrogen bonding interactions have been studied by the atoms in molecules (AIM) analysis of the electron density. The aromaticity of phenyl group has been determined by a selective hydrogenation protocol. The pattern of the extent of aromacity, due intramolecular interactions, varies very little between the two models studied.
[Mh] Termos MeSH primário: Epinefrina/química
Compostos de Fenilamônio/química
[Mh] Termos MeSH secundário: Modelos Moleculares
Conformação Molecular
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Phenylammonium Compounds); X4W3ENH1CV (Norepinephrine); YKH834O4BH (Epinephrine)
[Em] Mês de entrada:0905
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:090226
[St] Status:MEDLINE
[do] DOI:10.1021/jp807353n

página 1 de 1

Refinar a pesquisa
  Base de dados : MEDLINE Formulário avançado   

    Pesquisar no campo  

Search engine: iAH v2.6 powered by WWWISIS

BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde