Application of Cascade Processes for the Synthesis of Polycyclic Ring Systems

这项研究的重点有三个方面。首先，采用一种新的[4+2]-环加成-重排序列来设置蛇皮草生物碱骨架的ABCE环核。其次，将采用串联硫离子/ n -酰基铵离子环化策略来获得在去乙基石叶碱中发现的吡罗[2,3-d]咔唑环框架。第三，将研究过渡金属介导的乙基重氮酮酰胺的环化，作为合成包括士的宁在内的多种生物碱的途径。有机和大分子化学项目是为了支持埃默里大学化学系阿尔伯特·帕德瓦博士的研究工作而设立的。Padwa教授将专注于开发串联或级联的方法，以在一次操作中形成几个碳-碳键和/或环系统。使用阳离子、阴离子、自由基、类碳化合物或周环过程的组合将导致制备具有有趣生物学特性的结构多样的合成靶标。该研究对研究生的培养和与制药工业相关的方法论的发展具有更广泛的影响。

The foci of this research are three-fold. First , a novel [4+2]-cycloaddition -rearrangement sequence will be used to set the ABCE cyclic core of the aspidosperma alkaloid skeleton. Second, a tandem thionium/N-acyliminium ion cyclization strategy will be used to afford the pyrrolo[2,3-d]carbazole ring framework found in deethylibophyllidene. Third, the transition metal mediated cyclization of acetylenic diazoketoamides will be studied as a route to the synthesis of a number of alkaloids including strychnine.With this Renewal award, the Organic and Macromolecular Chemistry Program is supporting the research efforts of Dr. Albert Padwa of the Department of Chemistry at Emory University. Professor Padwa will focus his work on the development of tandem, or cascade, methods for the formation of several carbon-carbon bonds and/or rings systems in a single operation. Using combinations of cationic, anionic, radical, carbenoid or pericyclic processes will lead to the preparation of structurally diverse synthetic targets possessing interesting biological properties. The research has broader impact for the training of graduate students and for the development of methodology pertinent to the pharmaceutical industry.