Antioxidative properties of nitroxyl radicals and hydroxyamines in reactions with triplet and deaminated kynurenine
作者:V. V. Yan’shole、I. A. Kirilyuk、I. A. Grigor’ev、S. V. Morozov、Yu. P. Tsentalovich
DOI:10.1007/s11172-010-0046-y
日期:2010.1
The reactions of triplet kynurenine and 4-(2-aminophenyl)-4-oxocrotonic acid, formed upon the thermal decomposition of kynurenine, with nitroxyl radicals and cyclic N-hydroxylamines were studied. Nitroxyl radicals were found to quench efficiently the triplet state of kynurenine (rate constant 3–6·.108 L mol-1 s-1). The quenching proceeds via the spin-exchange mechanism and affords no new products.
研究了犬尿氨酸热分解后形成的三线态犬尿氨酸和 4-(2-氨基苯基)-4-氧代巴豆酸与硝酰基自由基和环状 N-羟胺的反应。发现硝酰基自由基有效地淬灭犬尿氨酸的三重态(速率常数 3–6·.108 L mol-1 s-1)。淬灭通过自旋交换机制进行并且没有提供新产品。在类似于生理学的条件下,硝酰基自由基和羟基胺都不会与 4-(2-氨基苯基)-4-氧代巴豆酸反应。
Formation of fluorophores from the kynurenine pathway metabolite N-formylkynurenine and cyclic amines involves transamidation and carbon–carbon bond formation at the 2-position of the amine
作者:Petr Tomek、Brian D. Palmer、Jackie D. Kendall、Jack U. Flanagan、Lai-Ming Ching
DOI:10.1016/j.bbagen.2015.04.007
日期:2015.9
showed that only cyclic amines unsubstituted at both positions adjacent to nitrogen could form fluorophores efficiently. The amino acids tryptophan and kynurenine, which lack the formamide group do not form such fluorophores. CONCLUSIONS NFK forms fluorophores in a not previously published reaction with cyclic amines. GENERAL SIGNIFICANCE Our study is the first to provide evidence for concurrent transamidation