Applications of Irreversible Photooxidation

在有机和高分子化学计划的支持下，亚利桑那州立大学化学和生物化学系的Ian Gould教授正在研究不可逆光氧化在阐明DNA氧化过程机制中的应用。N-烷氧基杂环的N-O键断裂提供母体杂环的自由基阳离子和烷氧基。这些不可逆的光裂解反应允许探索这些反应物种中的每一个的反应化学。在阐明N-烷氧基杂环光化学的机制和范围之后，Gould教授将确定双链DNA中嘌呤自由基阳离子的氧化电位和寿命，并探索控制其反应性的因素。最后，将使用基于量子产率准确测量的机械方法研究DNA的氧化损伤，通过嘌呤碱基的单电子氧化和通过糖骨架的自由基提取来量化单链切割的绝对和相对效率。DNA的氧化导致反应性中间体物质。这些活性中间体的基本反应化学的探索将导致更详细地了解氧化过程，这是在DNA化学和生物化学的核心重要性。亚利桑那州立大学化学和生物化学系的Ian Gould教授通过开发独特的试剂，使氧化的DNA物质能够有效地形成，正在探索这些重要但只是短暂存在的反应中间体的反应化学。

With the support of the Organic and Macromolecular Chemistry Program, Professor Ian Gould, of the Department of Chemistry and Biochemistry at Arizona State University, is studying applications of irreversible photooxidation in the elucidation of the mechanisms of oxidative processes in DNA. N-O bond cleavage of N-alkoxyheterocycles affords the radical cation of the parent heterocycle and an alkoxy radical. These irreversible photocleavage reactions allow exploration of the reaction chemistry of each of these reactive species. Following elucidation of the mechanisms and scope of the photochemistry of N-alkoxyheterocycles, Professor Gould will determine the oxidation potentials and lifetimes of purine radical cations in duplex DNA and explore the factors controlling their reactivity. Finally, oxidative damage in DNA will be studied using a mechanistic approach based on accurate measurements of quantum yields, quantifying the absolute and relative efficiencies of single-strand cleavage via one-electron oxidation of purine bases and via radical abstraction from the sugar backbone.Oxidation of DNA leads to reactive intermediate species. Exploration of the fundamental reaction chemistry of these reactive intermediates will lead to a more detailed understanding of oxidative processes which are of central importance in DNA chemistry and biochemistry. By developing unique reagents allowing the efficient formation of oxidized DNA species, Professor Ian Gould, of the Department of Chemistry and Biochemistry at Arizona State University, is exploring the reaction chemistry of these important but only transiently existent reactive intermediates.