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

该奖项将支持克莱姆森大学Rudolph abramovich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）与已知天然环合成有关的大环二苯基醚内酯，例如Combrestastin D-2。双方研究优势互补。劳特博士在类黄酮化学方面的工作为合成类黄酮和黄烷醇的介质环同源物提供了基础。阿布拉莫维奇博士关于氮离子环化的研究提供了一种新颖的方法。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形成C-O-C键。克莱姆森的研究将探索分子模型研究（MMX和AM1）是否可以预测哪些起始材料具有合适的几何结构来进行大环化。＊＊＊

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. ***