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1.
Org Biomol Chem ; 11(45): 7869-76, 2013 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-24129548

RESUMO

A palladium(II)-catalyzed direct acylation of acetophenone N-Boc hydrazones with aldehydes via C-H bond activation is described. This protocol provides direct access to a range of 1,2-diacylbenzenes, which are useful precursors to construct biologically interesting and pharmaceutically important compounds.


Assuntos
Aldeídos/química , Benzofenonas/síntese química , Hidrazonas/química , Compostos Organometálicos/química , Paládio/química , Acilação , Benzofenonas/química , Catálise , Estrutura Molecular
2.
Org Biomol Chem ; 11(17): 2766-71, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23493982

RESUMO

A palladium-catalyzed ortho-acylation of N-benzyltriflamides from the alcohol oxidation level via C-H bond activation is described. These transformations have been applied to a wide range of substrates, and typically proceed with excellent levels of chemoselectivity and with high functional group tolerance.


Assuntos
Álcoois/química , Amidas/química , Cetonas/síntese química , Catálise , Cetonas/química , Estrutura Molecular , Oxirredução , Paládio/química
3.
Chem Commun (Camb) ; 49(16): 1654-6, 2013 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-23334232

RESUMO

A palladium-catalyzed decarboxylative acylation of phenylacetamides with α-oxocarboxylic acids via C-H bond activation is described. This protocol provides efficient access to a range of ortho-acyl phenylacetamides, which can be easily converted to 3-isochromanone derivatives.


Assuntos
Acetamidas/química , Ácidos Carboxílicos/química , Cromonas/síntese química , Compostos Organometálicos/química , Paládio/química , Acilação , Catálise , Cromonas/química , Descarboxilação , Estrutura Molecular
4.
Chem Commun (Camb) ; 49(9): 925-7, 2013 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-23247196

RESUMO

A mild, practical and efficient palladium-catalyzed decarboxylative ortho-acylation of O-methyl ketoximes with α-keto acids via C-H bond activation is described. In these reactions, a broad range of O-methyl ketoximes and α-keto acids undergoes the decarboxylative cross-coupling reactions with high selectivities and good tolerance.


Assuntos
Cetoácidos/química , Oximas/química , Paládio/química , Acilação , Catálise
5.
Bioorg Med Chem Lett ; 22(11): 3653-5, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22543029

RESUMO

The synthesis and biological evaluation of a series of novel norlignans are described. Norlignans were evaluated for their inhibitory activity on the release of ß-hexosaminidase, a marker of degranulation, from RBL-2H3 cells induced by the IgE-antigen complex. The results showed that norlignans 4c and 4e potently inhibited degranulation, with IC(50) values of 18.3 and 17.9 µM, respectively.


Assuntos
Complexo Antígeno-Anticorpo/imunologia , Degranulação Celular/efeitos dos fármacos , Lignanas/química , Animais , Basófilos/fisiologia , Linhagem Celular Tumoral , Imunoglobulina E/química , Imunoglobulina E/metabolismo , Lignanas/síntese química , Lignanas/farmacologia , Ratos , Relação Estrutura-Atividade , beta-N-Acetil-Hexosaminidases/metabolismo
6.
Org Lett ; 13(16): 4390-3, 2011 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-21793534

RESUMO

A rhodium-catalyzed oxidative acylation of benzamides with aryl aldehydes via direct sp(2) C-H bond cleavage is described. In the presence of [Cp*RhCl(2)](2), AgSbF(6), and silver carbonate as an oxidant, N,N-diethyl benzamides can be effectively carbonylated to yield ortho-acyl benzamides.


Assuntos
Aldeídos/química , Benzamidas/química , Carbono/química , Hidrogênio/química , Ródio/química , Acilação , Catálise , Estrutura Molecular , Oxirredução
7.
J Org Chem ; 76(7): 2214-9, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21370932

RESUMO

One-pot synthesis of symmetric 1,4-disubstituted 1,3-diynes from iodoarenes and propiolic acid via Sonogashira reaction followed by Pd-catalyzed decarboxylative homocoupling is developed in high yields. Also, this system allows the one-pot synthesis of unsymmetric 1,4-disubstituted 1,3-diynes by cross-coupling of two different 3-substituted propiolic acids.


Assuntos
Alcinos/química , Di-Inos/química , Di-Inos/síntese química , Paládio/química , Propionatos/química , Catálise , Técnicas de Química Combinatória , Reagentes de Ligações Cruzadas/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
8.
Mol Cells ; 31(4): 343-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21359677

RESUMO

Interphasic chromatin condenses into the chromosomes in order to facilitate the correct segregation of genetic information. It has been previously reported that the phosphorylation and methylation of the N-terminal tail of histone H3 are responsible for chromosome condensation. In this study, we demonstrate that the deacetylation and methylation of histone H3 lysine 9 (H3K9) are required for proper chromosome condensation. We confirmed that H3K9ac levels were reduced, whereas H3K9me3 levels were increased in mitotic cells, via immunofluorescence and Western blot analysis. Nocodazole treatment induced G2/M arrest but co-treatment with TSA, an HDAC inhibitor, delayed cell cycle progression. However, the HMTase inhibitor, AdoX, had no effect on nocodazole-induced G2/M arrest, thereby indicating that sequential modifications of H3K9 are required for proper chromosome condensation. The expression of SUV39H1 and SETDB1, H3K9me3-responsible HMTases, are specifically increased along with H3K9me3 in nocodazole-arrested buoyant cells, which suggests that the increased expression of those proteins is an important step in chromosome condensation. H3K9me3 was highly concentrated in the vertical chromosomal axis during prophase and prometaphase. Collectively, the results of this study indicate that sequential modifications at H3K9 are associated with correct chromosome condensation, and that H3K9me3 may be relevant to the condensation of chromosome length.


Assuntos
Ciclo Celular , Cromossomos Humanos/metabolismo , Histonas/metabolismo , Hidroximetil e Formil Transferases/metabolismo , Lisina/metabolismo , Processamento de Proteína Pós-Traducional , Acetilação , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cromatina/química , Cromatina/metabolismo , Cromossomos Humanos/química , Histonas/química , Humanos , Lisina/química , Metilação , Nocodazol/farmacologia , Conformação de Ácido Nucleico
9.
BMB Rep ; 43(2): 133-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20193133

RESUMO

We have performed analyses using ancient DNA extracted from 25 excavated human bones, estimating around the 1(st) century B.C. Ancient human bones were obtained from Nukdo Island, which is located off of the Korean peninsula of East Asia. We made concerted efforts to extract ancient DNA of high quality and to obtain reproducible PCR products, as this was a primary consideration for this extensive kind of undertaking. We performed PCR amplifications for several regions of the mitochondrial DNA, and could determine mitochondrial haplogroups for 21 ancient DNA samples. Genetic information from mitochondrial DNA belonged to super-haplogroup M, haplogroup D or its sub-haplogroups (D4 or D4b), which are distinctively found in East Asians, including Koreans or Japanese. The dendrogram and principal component analysis based on haplogroup frequencies revealed that the Nukdo population was close to those of the East Asians and clearly distinguished from populations shown in the other regions. Considering that Nukdo is geologically isolated in the southern part of them Korean peninsula and is a site of commercial importance with neighboring countries, these results may reflect genetic continuity for the habitation and migration of ethnic groups who had lived in a particular area in the past. Therefore, we suggest that phylogenetic analyses of ancient DNA have significant advantages for clarifying the origins and migrations of ethnic groups, or human races.


Assuntos
DNA Mitocondrial/classificação , Osso e Ossos/química , DNA Mitocondrial/química , Haplótipos , Humanos , Filogenia , Análise de Componente Principal , República da Coreia , Análise de Sequência de DNA
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