ORGN 440 |
| James H. Rigby, Weidong Zhang, Weitong Dong, and Mary J. Heeg. Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI 48202 |
| Nucleophilic carbenes have recently emerged as powerful 1,1-dipole equivalents for the construction of functionalized hydroindolone derivatives via a novel [4+1] cycloaddition with vinyl isocyanates in our laboratory. This methodology has been successfully used in the total synthesis of several alkaloids, such as tazettine and mesembrine. Currently, we are investigating the total synthesis of stenine (1), a member of Stemona alkaloids which are isolated from the root extracts of Stemona species. Our synthetic strategy involves the assembly of hydroindolone 4 by using [4+1] cycloaddition of vinyl isocyanate 2 and bisthiocarbene 3. Another key transformation of our approach is to install the 7-membered ring moiety of the azepinoindole on highly functionalized hydroindolone via a 7-endo trig radical cyclization (5→6). Current efforts are directed toward utilizing 7-endo radical cyclization to provide 6 and further elaborating it to stenine (1). |
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Total Synthesis, Asymmetric Reactions and Syntheses, Bioorganic
9:00 AM-11:00 AM, Wednesday, March 31, 2004 Anaheim Convention Center -- Hall C, Poster
Division of Organic Chemistry |
