Concise Chemoenzymatic Three-Step Total Synthesis of Isosolenopsin through Medium Engineering
作者:Robert C. Simon、Christine S. Fuchs、Horst Lechner、Ferdinand Zepeck、Wolfgang Kroutil
DOI:10.1002/ejoc.201300157
日期:2013.6
A short and efficient total synthesis of the alkaloid isosolenopsin and its enantiomer has been achieved. In the key step, a omega-transaminase catalyzed the regioselective mono-amination of the diketone pentadecane-2,6-dione which was obtained in a single step via Grignard reaction. Initial low conversions in the biotransformation could be overcome by optimisation of the reaction conditions employing
已经实现了生物碱异麦芽酚肽及其对映异构体的短而有效的全合成。在关键步骤中,ω-转氨酶催化了通过格氏反应在一步中获得的二酮十五烷-2,6-二酮的区域选择性单胺化。通过使用合适的助溶剂优化反应条件,可以克服生物转化中最初的低转化率。在存在20%(体积)DMF或正庚烷的情况下,使用两种源自节杆菌的对映体互补的ω-转氨酶在30-40摄氏度之间可获得最佳结果。在这些条件下,转化率> 99%,立体声控制效果最佳(ee> 99%)。生物催化产物的非对映化学还原(H2 / Pd / C)得到目标化合物。