Divergent Total Syntheses of C3 a−C7′ Linked Diketopiperazine Alkaloids (+)-Asperazine and (+)-Pestalazine A Enabled by a Ni-Catalyzed Reductive Coupling of Tertiary Alkyl Chloride
作者:Long Luo、Xiao-Yong Zhai、Ya-Wen Wang、Yu Peng、Hegui Gong
DOI:10.1002/chem.201805682
日期:2019.1.18
Short gram‐scale asymmetric syntheses of asperazine, pestalazine A, and their unnatural congeners thereof, have been achieved in ≈10 steps by using readily accessible starting materials. The nickel‐catalyzed reductive coupling protocol was utilized as a key step for the direct construction of C3asp3−C7′sp2 bond furnishing the diaryl‐substituted quaternary carbon centers with remarkable steric hindrance
通过使用容易获得的起始原料,在约10个步骤中就完成了短克级不对称阿斯巴嗪,香蒜嗪A及其非天然同源物的合成。镍催化还原偶联协议被用作的C3a的直接结构的关键步骤SP3 -C7'的sp2键家具具有显着空间位阻二芳基取代的季碳中心。在温和的反应条件下,简化了对异二聚色氨酸核心结构的访问,使该策略在具有独特C3a-C7'键的其他相关寡聚吡咯并吲哚啉生物碱的简明合成中具有广阔的前景。