U.S.-Portugal Cooperative Research: Synthesis of Medium RingHomologs of Flavonoids and Diphenyl Ethers via Nitrenium Ions

Abramovitch 9304094 该奖项将支持克莱姆森大学鲁道夫·阿布拉莫维奇和葡萄牙里斯本大学 A. P. Rauter 之间的合作研究。 该项目将开发（i）已知类黄酮和黄烷醇的中环同系物和（ii）与已知天然存在的环合成相关的大环二苯醚内酯的合成，例如考布司他汀D-2。 两位参与者的研究优势是互补的。 Rauter 博士在类黄酮化学方面的工作为合成类黄酮和黄烷醇的中环同系物提供了基础。 阿布拉莫维奇博士关于使用氮离子环化的研究提供了一种允许新颖且容易获得的方法。 该项目的葡萄牙部分将探索酮（或烯醇）是否可以捕获芳基氮离子以形成C-O-C键。 克莱姆森大学的研究将探讨分子模型研究（MMX 和 AM1）是否可以预测哪些起始材料具有进行大环化的正确几何形状。 ***

Abramovitch 9304094 This award will support collaborative research between Rudolph Abramovitch, Clemson University, and A. P. Rauter, University of Lisbon, Portugal. This project will develop the synthesis of (i) medium ring homologs of known flavonoids and flavanols and (ii) macrocyclic diphenyl ether lactones related to known naturally occurring ring synthesis, e.g. Combrestastin D-2. The research strengths of the two participants are complementary. Dr. Rauter's work on the chemistry of flavonoids has provided a basis for synthesizing medium ring homologs of flavonoids and flavanols. Dr. Abramovitch's on cyclizations using nitrenium ions provides a methodology permitting novel and ready access. The Portuguese part of the project will explore whether ketones (or enols) can trap arylnitrenium ions to form C-O-C bonds. The Clemson study will explore whether molecular modelling studies (MMX and AM1) can predict which starting materials have the right geometry to undergo macrocyclizations. ***