Development of a Unified Enantioselective, Convergent Synthetic Approach Toward the Furanobutenolide-Derived Polycyclic Norcembranoid Diterpenes: Asymmetric Formation of the Polycyclic Norditerpenoid Carbocyclic Core by Tandem Annulation Cascade
作者:Robert A. Craig、Russell C. Smith、Jennifer L. Roizen、Amanda C. Jones、Scott C. Virgil、Brian M. Stoltz
DOI:10.1021/acs.joc.7b02825
日期:2018.4.6
enantioselective and diastereoselective approach toward the synthesis of the tetracyclic scaffold of the furanobutenolide-derived polycyclic norditerpenoids is described. Focusing on synthetic efforts toward ineleganolide, the synthetic approach utilizes a palladium-catalyzed enantioselective allylic alkylation for the construction of the requisite chiral tertiary ether. A diastereoselective cyclopropanation–Cope
描述了对呋喃丁烯内酯衍生的多环降二萜类化合物的四环支架的合成的对映选择性和非对映选择性方法。着眼于针对烯丙基醇的合成努力,合成方法利用钯催化的对映选择性烯丙基烷基化反应来构建所需的手性叔醚。非对映选择性的环丙烷化-Cope重排级联使ineleganolide [6,7,5,5]-四环支架的会聚组装成为可能。讨论了用于此关键串联环化工艺的底物的研究,以及[6,7,5,5]-四环支架的合成操作以及[6,7,5,5]-四环支架的伊莱诺醇内酯向内酯的相互转化的尝试。 ca虫内酯A及其天然异构体的[7,6,5,5]核异构体。