Application of the Palladium(0)-Catalyzed Ullmann Cross-Coupling Reaction in a Total Synthesis of (±)-Aspidospermidine and thus Representing an Approach to the Lower Hemisphere of the Binary Indole - Indoline Alkaloid Vinblastine
作者:Martin G. Banwell、David W. Lupton、Anthony C. Willis
DOI:10.1071/ch05181
日期:——
reaction to give the bicyclic system 5. In contrast, the related compound 46, incorporating tethered enone and azide moieties, engaged in an intramolecular 1,3-dipolar cycloaddition reaction to give, presumably via an intermediate triazoline, the isolable and ring-fused aziridine 47. This was then converted, over two steps, into the previously reported tetrahydrocarbazole 4. Application of established protocols
作为针对构建抗癌剂长春碱 (1) 的正在进行的研究的一部分,已经合成了相关但结构不太复杂的天然产物 aspidospermidine (3)。针对目标 3 采用了两种方法。在第一个中,这是不成功的,制备了胺连接的烯酮 6,但这未能参与关键的分子内共轭加成反应,得到双环系统 5。相比之下,相关的化合物 46,结合了连接的烯酮和叠氮化物部分,参与分子内的 1,3-偶极环加成反应,可能通过中间体三唑啉,得到可分离的稠环氮丙啶 47。然后经过两步将其转化为先前报道的四氢咔唑 4。