Enantioselective Total Synthesis of (−)-Maoecrystal V
作者:Changwu Zheng、Igor Dubovyk、Kiel E. Lazarski、Regan J. Thomson
DOI:10.1021/ja5109694
日期:2014.12.24
The enantioselectivesynthesis of maoecrystal V, a cytotoxic polycyclic diterpene, is described. Key reactions in the synthesis include an intramolecular Heck reaction, an oxidative cycloetherification, and an intermolecular Diels-Alder reaction to forge the carbocyclic core in a concise and stereoselective manner. Late-stage amine and C-H oxidation is used to install the final functional groups required
作者:Wei-bin Zhang、Wen-bin Shao、Fu-zhuo Li、Jian-xian Gong、Zhen Yang
DOI:10.1002/asia.201500564
日期:2015.9
ent‐kaurane diterpene, has been accomplished. Key steps of the current strategy involve an early‐stage semipinacolrearrangement reaction for the construction of the C10 quaternary stereocenter, a rhodium‐catalyzed intramolecular O−H insertion reaction, and a sequential Wessely oxidativedearomatization/intramolecular Diels–Alder reaction to forge the pentacyclic framework of maoecrystal V.
highly congested ent-kaurane diterpene maoecrystal V is presented. This route, which has been several years in the making, is loosely modeled after a key pinacol shift in the proposed biosynthesis. Only 11 steps, many of which are strategic in that they build key skeletal bonds and incorporate critical functionalities, are required to access (−)-maoecrystal V. Several unique and unexpected maneuvers are
提出了一种通向高度拥挤的 ent-kaurane 二萜 maoecrystal V 的权宜之计、实用和对映选择性途径。这条路线已经酝酿了好几年,它是在拟议的生物合成中的关键频哪醇转变之后松散地建模的。访问 (-)-maoecrystal V 只需要 11 个步骤,其中许多步骤具有战略意义,因为它们构建了关键的骨架键并整合了关键功能。在这个潜在可扩展的途径中,有几个独特和意想不到的操作。对生物活性的重新评估使人们质疑围绕这种天然产品的最初繁荣。