RADICAL MEDIATED CYCLIZATION REACTIONS

许多具有重要治疗作用的天然产品和药剂 可由官能化的环戊烷和二氧杂环戊烷衍生物制备。 不断发展的方法，以实现高效和 提出了这些环系的立体选择性合成方法。这 方法学是基于自由基介导的加成反应 官能化的碳碳键上的烯烃或相关物种 适当活化的乙烯基环丙烷直接合成环戊烷 单位。重点是提高目前的糖尿病水平-- 成键时的立体选择性和对映体选择性。此外， 基于自由基环化/异构化反应的新进展 用于构建高度官能化的环戊醇物种的是 有计划的。最后，非对映选择性遥控器(Gamma)功能化 将探索仲醇类化合物。 抗肿瘤抗生素布雷菲尔丁A和抗白血病药物的合成 试剂洛格拉米特，每种都利用环状-环状-环状的分子内变体- 戊二酰化过程，将进行研究。成功完成 这些合成将以最有效的方式提供靶标(或类似物) 到目前为止的态度。

Many therapeutically important natural products and pharmaceutical agents can be prepared from functionalized cyclopentane and dioxolane derivatives. The continued development of methodology for the efficient and stereoselective synthesis of these ring systems is proposed. This methodology is based on the free radical mediated addition of functionalized olefins or related species across the carbon-carbon bond of suitably activated vinylcyclopropanes to afford directly the cyclopentane units. Emphasis is placed on enhancing current levels of dia- stereoselectivity and enantioselectivity upon bond formation. Further, the development of novel free radical-based annelation/isomerization reactions for the construction of highly functionalized cyclopentanol species is planned. Finally, diastereoselective remote (Gamma) functionalization of secondary alcohols will be explored. Syntheses of the antitumor antibiotic brefeldin A and The antileukemic agent rocaglamide, which each utilize intramolecular variants of the cyclo- pentannelation process, will be investigated. Successful completion of these syntheses will afford the targets (or analogs) in the most efficient manner to date.