Formation of <i>N</i>-Nitrosamines and <i>N</i>-Nitramines by the Reaction of Secondary Amines with Peroxynitrite and Other Reactive Nitrogen Species: Comparison with Nitrotyrosine Formation
作者:Mitsuharu Masuda、Howard F. Mower、Brigitte Pignatelli、Irena Celan、Marlin D. Friesen、Hoyoku Nishino、Hiroshi Ohshima
DOI:10.1021/tx990120o
日期:2000.4.1
mechanism, involving one-electron oxidation by peroxynitrite of secondary amines to form amino radicals (R(2)N(*)), which react with nitric oxide ((*)NO) or nitrogen dioxide ((*)NO(2)) to yield nitroso and nitro secondary amines, respectively. Reaction of morpholine with NO(*) and superoxide anion (O(2)(*)(-)), which were concomitantly produced from spermine NONOate and by the xanthine oxidase systems, respectively
活性氮物质包括氮氧化物(N(2)O(3)和N(2)O(4)),过氧亚硝酸盐(ONOO(-))和硝酰氯(NO(2)Cl)被暗示为引起炎症和癌症的原因。我们研究了仲胺与过氧亚硝酸盐的反应,发现同时形成了N-亚硝胺和N-硝胺。在碱性pH下,过氧亚硝酸盐比在中性pH下更容易被亚硝酸盐亚硝化,而在pH 8.5下,过氧亚硝酸盐的硝化作用是最佳的。该反应中亚硝基吗啉的收率是碱性pH下亚硝基吗啉的3倍,而在pH <7.5下形成的亚硝基吗啉是亚硝基吗啉的2倍。对于吗啉-过亚硝酸盐反应,低浓度的碳酸氢盐可增强硝化作用,但过量的碳酸氢盐可抑制硝化作用。亚硝酸盐被过量的碳酸氢盐抑制。在此基础上,我们提出了一种自由基机理,涉及一种通过仲胺的过氧亚硝酸盐单电子氧化形成氨基(R(2)N(*))的基团,该基团与一氧化氮((*)NO)或二氧化氮反应((*)NO(2))分别产生亚硝基和硝基仲胺。吗啉与NO(*)和超氧阴离子(