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1.
Comb Chem High Throughput Screen ; 21(7): 526-532, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30152280

RESUMO

AIM AND OBJECTIVE: In this work, we synthesized and characterized a novel Brönsted acidic ionic liquid from the reaction of N, N, N', N'-tetramethylethylenediamine with chlorosulfonic acid and explored its catalytic activity in 1, 8-dioxo-octahydroxanthenes synthesis. MATERIALS AND METHODS: Dimedone, aryl aldehydes, and the ionic liquid as the catalyst were reacted under solvent-free conditions. The progressive of the reaction was monitored by a thin layer of chromatography (ethyl acetate/n-hexane = 1/5). All products were characterized as the basis of their spectra data and melting point by comparison with those reported in the literature. RESULTS: The prepared ionic liquid was successfully applied in the synthesis of 1, 8-dioxooctahydroxanthenes in good to high yields on the reaction of aryl aldehyde and dimedone at 120°C under solvent-free conditions. CONCLUSION: This research demonstrates that the catalyst is impressive for 1, 8-dioxo-octahydroxanthenes synthesis under solvent-free conditions.


Assuntos
Etilenodiaminas/química , Líquidos Iônicos/química , Xantenos/síntese química , Etilenodiaminas/síntese química , Ensaios de Triagem em Larga Escala , Líquidos Iônicos/síntese química , Estrutura Molecular , Xantenos/química
2.
Anal Bioanal Chem ; 407(20): 6127-36, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26163131

RESUMO

The effects of six synthetic imidazolium-based ionic liquids (ILs) on the Cu(II)-catalyzed chemiluminescence of lucigenin (Luc-CL) in the pH range 6.0-11 were investigated. Preliminary experiments found that the CL emission was strongly enhanced or inhibited in the presence of the ILs. The degree of enhancement or inhibition of the CL intensity in the presence of each IL was related to the molecular structure of the IL, the medium used, and the pH. The maximum enhancement of the CL intensity was observed at pH 9.0 (amplification factor = 443). This decrease in the pH at which maximum CL enhancement occurred and the substantial signal amplification of the Luc-CL may be related to a strong interaction between Cu(II) and the imidazolium ring of superior ILs at this pH. Additionally, the formation of IL microdomains in semi-aqueous media permitted more solubility of the product yielded by the Luc-CL reaction (N-methylacridone), which could increase the CL intensity. To obtain consistent data on the catalytic efficiency of Cu(II) in the presence of various ILs as well as the corresponding CL emission intensities, fluorescence quantum yields (Φ F) of lucigenin were measured under the same conditions. Comparison of the data pointed to the mechanism that controls the properties of Luc-CL in the presence of the Cu(II)/IL complexes. Based on the catalytic effect of the Cu(II)/IL complex and the measurement of the enzymatically generated H2O2, a novel, simple, and sensitive CL method for determining glucose with a detection limit (LoD) of 6.5 µM was developed. Moreover, this method was satisfactorily applied to the determination of glucose in human serum and urine samples. Graphical Abstract The lucigenin chemiluminescence assay for H2O2 and glucose using imidazolium-based ionic liquid derivatives/Cu(II) complexes as efficient catalysts at pH 9.0.


Assuntos
Acridinas/química , Glicemia/análise , Glicosúria/diagnóstico , Peróxido de Hidrogênio/análise , Líquidos Iônicos/química , Substâncias Luminescentes/química , Medições Luminescentes/métodos , Catálise , Complexos de Coordenação/química , Cobre/química , Glucose/análise , Humanos , Imidazóis/química , Limite de Detecção , Luminescência , Modelos Moleculares
3.
Org Lett ; 14(15): 3838-41, 2012 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-22823341

RESUMO

A reaction of dithiocarbamic acid salts with carbonyl compounds was investigated for the first time in the presence of BF(3)·OEt(2). The reaction is temperature dependent and gives gem-bis(dithiocarbamates) at 35-45 °C as a molecule with high equivalents of dithiocarbamate groups. At lower temperatures (15-20 °C), the 2-iminium-1,3-dithietane is obtained as the only product. The structure of a 2-iminium-1,3-dithietane was accomplished by X-ray crystallographic analysis.

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