103963-58-2Relevant articles and documents
Development of a stable isotope dilution analysis with liquid chromatography-tandem mass spectrometry detection for the quantitative analysis of di- and trihydroxybenzenes in foods and model systems
Lang, Roman,Mueller, Christoph,Hofmann, Thomas
, p. 5755 - 5762 (2006)
A straightforward stable isotope dilution analysis (SIDA) for the quantitative determination of the di-and trihydroxybenzenes catechol (1), pyrogallol (2), 3-methylcatechol (3), 4-methylcatechol (4), and 4-ethylcatechol (5) in foods by means of liquid chromatography-tandem mass spectrometry was developed. With or without sample preparation involving phenylboronyl solid phase extraction, the method allowed the quantification of the target compounds in complex matrices such as coffee beverages with quantification limits of 9 nmol/L for 4-ethylcatechol, 24 nmol/L for catechol, 3-methyl-, and 4-methylcatechol, and 31 nmol/L for pyrogallol. Recovery rates for the analytes ranged from 97 to 103%. Application of the developed SIDA to various commercial food samples showed that quantitative analysis of the target compounds is possible within 30 min and gave first quantitative data on the amounts of di- and trihydroxybenzenes in coffee beverage, coffee powder, coffee surrogate, beer, malt, roasted cocoa powder, bread crust, potato crisps, fruits, and cigarette smoke and human urine. Model precursor studies revealed the carbohydrate/amino acid systems as well as the plant polyphenols catechin and epicatechin as precursors of catechol and 5-O-caffeoylquinic acid, caffeic acid as a precursor of catechol and 4-ethylcatechol, and gallocatechin, epigallocatechin, and gallic acid as precursors of pyrogallol.
Aromatic ring favorable and efficient H-D exchange reaction catalyzed by Pt/C
Sajiki, Hironao,Ito, Nobuhiro,Esaki, Hiroyoshi,Maesawa, Tsuneaki,Maegawa, Tomohiro,Hirota, Kosaku
, p. 6995 - 6998 (2005)
An effective and applicable Pt/C-catalyzed deuteration method of aromatic rings using D2O as a deuterium source under hydrogen atmosphere was developed. Five percent Pt/C would lead to quite effective H-D exchange results on the aromatic ring systems. The reaction is general for a variety of aromatic compounds including biologically active compounds.
Elucidation of the Coordination Chemistry of the Enzyme-Substrate Complex of Catechol 1,2-Dioxygenase by NMR Spectroscopy
Que, Lawrence,Lauffer, Randall B.,Lynch, John B.,Murch, Bruce P.,Pyrz, Joseph, W.
, p. 5381 - 5385 (1987)
The coordination chemistry of the active site iron in catechol 1,2-dioxyygenase (CTD) from Pseudomonas putida (ATCC 23974) has been probed with NMR spectroscopy.The high-spin ferric center gives rise to paramagnetically shifted resonances in the range of
Efficient and selective Pt/C-catalyzed H-D exchange reaction of aromatic rings
Ito, Nobuhiro,Esaki, Hiroyoshi,Maesawa, Tsuneaki,Imamiya, Eikoh,Maegawa, Tomohiro,Sajiki, Hironao
experimental part, p. 278 - 286 (2009/03/12)
An effective and applicable deuteration method for aromatic rings using Pt/C-D2O-H2 system was established. Especially, phenol was fully deuterated even at room temperature, and other electron-rich aromatic nuclei were efficiently deuterated under mild conditions. The scope and limitations of the presence method and its application to the synthesis of deuterium-labeled biologically active compounds and deuterium-labeled building blocks for practical multi-gram scale syntheses are reported. 2008 The Chemical Society of Japan.
