Arora A, Valcic S, Cornejo S, Nair M G, Timmermann B N, Liebler D C
Department of Pharmacology and Toxicology and Southwest Environmental Health Sciences Center, College of Pharmacy, The University of Arizona, Tucson 85721, USA.
Chem Res Toxicol. 2000 Jul;13(7):638-45. doi: 10.1021/tx000015a.
Antioxidant actions of the soy isoflavone genistein are believed to contribute to its overall chemopreventive activity. However, the mechanisms of its antioxidant reactions remain unknown. The objective of this study was to characterize the reaction products of genistein (5,7,4'-trihydroxyisoflavone) with peroxyl radicals generated by thermolysis of 2,2'-azobis(2,4-dimethylvaleronitrile) (AMVN). Genistein oxidations with AMVN-derived peroxyl radicals yielded orobol (5,7,3',4'-tetrahydroxyisoflavone), a hydroxylated derivative of genistein, and several stable adducts of 4'-oxogenistein with AMVN-derived radicals. Some of these adducts include novel structures resulting from secondary oxidations of the AMVN-derived moiety. For all the observed oxidation products, the modifications occurred on the B-ring of the molecule. Genistein oxidation product structures provide potentially useful markers of genistein antioxidant chemistry.
大豆异黄酮染料木黄酮的抗氧化作用被认为有助于其整体化学预防活性。然而，其抗氧化反应的机制仍不清楚。本研究的目的是表征染料木黄酮（5,7,4'-三羟基异黄酮）与2,2'-偶氮二（2,4-二甲基戊腈）（AMVN）热解产生的过氧自由基的反应产物。染料木黄酮与AMVN衍生的过氧自由基氧化反应生成了刺芒柄花素（5,7,3',4'-四羟基异黄酮），它是染料木黄酮的一种羟基化衍生物，以及几种4'-氧代染料木黄酮与AMVN衍生自由基的稳定加合物。其中一些加合物包括由AMVN衍生部分的二次氧化产生的新结构。对于所有观察到的氧化产物，修饰都发生在分子的B环上。染料木黄酮氧化产物结构为染料木黄酮抗氧化化学提供了潜在有用的标记物。
