Total Synthesis of (±)-Didehydrostemofoline (Asparagamine A) and (±)-Isodidehydrostemofoline

详细信息    查看全文

• 作者：Markus Brü ; ggemann ; Andrew I. McDonald ; Larry E. Overman ; Mark D. Rosen ; Lothar Schwink ; and Jeremy P. Scott
• 刊名：Journal of the American Chemical Society
• 出版年：2003
• 出版时间：December 17, 2003
• 年：2003
• 卷：125
• 期：50
• 页码：15284 - 15285
• 全文大小：69K
• 年卷期：v.125,no.50(December 17, 2003)
• ISSN：1520-5126

文摘

The first total syntheses of (±)-didehydrostemofoline (1) and (±)-isodidehydrostemofoline (3) are reported. The synthesis begins with the Diels-Alder reaction of readily available pyrrole 9 and ethyl (E)-3-nitroacrylate, the latter serving as a regioinverted equivalent of ketene. After hydrogenation to prevent retro-Diels-Alder reaction, the major cycloadduct is transformed to 7-azabicyclo[2.2.1]heptanol 14. Aza-Cope-Mannich reaction of the formaldiminium derivative of 14 delivers 1-azatricyclo[5.3.0.0^4.10]decane 15, which in 15 additional steps is converted to 1 and 3.