OXOPORPHINATOIRON(V) OXIDATION OF POLYCYCLIC AROMATICS

多环芳烃(PAH)的单氧化反应 细胞色素P450是一种重要的生物反应，负责 用于将多环芳烃激活为最终致癌形式。 然而，这种反应在#年仅受到有限的关注。 使用卟啉铁催化剂的模型研究旨在模拟 细胞色素P450活性。这次会议提出的工作总目标是 研究是为了深入了解细胞色素P450介导的 通过研究一系列模型氧化反应，使用 多环芳烃、卟啉铁催化剂和过氧酸单氧供体。 过氧酸对卟啉铁络合物的作用 氧铁基卟啉阳离子自由基(正式的铁(V)络合物)。 这一物种与血红素介导的氧化有关。 模型和酶系统都有，但只有一种氧铁基卟啉 阳离子自由基络合物迄今已被表征。因此 最初的具体目标是描述一系列 氧-铁基卟啉阳离子自由基的两面衍生 受阻络合膦酸铁(III)络合物 氧化电位低。既弱又强 配位的阴离子配体将进一步调节 铁(V)中间体。物理化学相关性 紫外-可见光谱、核磁共振氢谱和穆斯堡尔谱参数的测定 将提供有关电子结构和电子产品的信息 不同轴向配体和苯环取代物的影响。 一旦生成氧铁基的条件得到优化 卟啉阳离子自由基的第二个特定目标将是 确定电荷转移在磷脂酰铁介导的过程中的作用 多环芳烃的氧化。苯并(A)芘的氧化，苯并(K)- 将对乙酰基菲和环戊二烯进行研究。收费 转移路径预计会导致介观氧化。 苯并(A)芘和苯并(K)乙基菲的位置，而 苯并(K)乙基菲和环戊烷的五元环- (Cd)芘通过亲电攻击对氧化起反应。

The monooxygenation of polycyclic aromatic hydrocarbons (PAH) by cytochrome P450 is an important biological reaction, responsible for activation of PAH to ultimate carcinogenic forms. Nevertheless, this reaction has received only limited attention in model studies employing porphinatoiron catalysts designed to mimic cytochrome P450 activity. The overall aim of work proposed in this study is to gain insight into the cytochrome P450-mediated oxidations by investigating a series of model oxidations employing PAH, porphinatoiron catalysts and peroxyacid monooxygen donors. The action of peroxyacids on porphinatoiron complexes can generate oxoferryl porphyrin cation radicals (formally iron (V) complexes). This species has been implicated in heme-mediated oxidations in both model and enzymic systems, but only one oxoferryl porphyrin cation radical complex has been characterized to-date. Therefore an initial specific objective is to characterize a series of oxoferryl porphyrin cation radicals derived from bifacially hindered phorphinatioiron (III) complexes spanning a range of high and low oxidation potentials. Both weakly and strongly coordinating anionic ligands will further modulate reactivity of the iron(V) intermediates. Correlation of physico-chemical parameters obtained by UV-vis, 1HNMR and Mossbauer spectroscopy will provide information on electronic structure and the electronic effects of varying axial ligands and phorphyrin ring substitutents. Once conditions have been optimized for the generation of oxoferryl porphyrin cation radicals, a second specific objective will be to determine the role of charge transfer in porphinatoiron-mediated PAH oxidations. The oxidation of benzo(a)pyrene, benz(k)- acephenanthrylene and cyclopenta(cd)pyrene will be studied. Charge transfer pathways are expected to result in oxidation of the meso positions of benzo(a)pyrene and benz(k)acephenanthrylene, while the 5-membered rings of benz(k)acephenanthrylene and cyclopenta- (cd)pyrene are reactive towards oxidation by electrophilic attack.