A Bioinspired Synthesis of (±)-Rubrobramide, (±)-Flavipucine, and (±)-Isoflavipucine
作者:Shoma Mizutani、Kenta Komori、Tohru Taniguchi、Kenji Monde、Kouji Kuramochi、Kazunori Tsubaki
DOI:10.1002/anie.201602910
日期:2016.8.8
A biomimetic synthesis of naturally occurring lactams rubrobramide, flavipucine, and isoflavipucine is described. The key step is a regioselective Darzens reaction between isobutyl glyoxal and an α‐bromo‐β‐ketoamide. The construction of the core tricyclic ring system of rubrobramide was achieved by a cascade reaction in a single step from an α,β‐epoxy‐γ‐lactam. Furthermore, the absolute configuration
描述了天然存在的内酰胺类溴溴酰胺,黄病毒素和异黄病毒素的仿生合成。关键步骤是异丁基乙二醛与α-溴-β-酮酰胺之间的区域选择性Darzens反应。溴溴酰胺核心三环系统的构建是通过一步法从α,β-环氧-γ-内酰胺开始的级联反应而实现的。此外,天然存在的(+)-溴溴酰胺的绝对构型由振动圆二色性确定。(±)-黄病毒嘌呤和(±)-异黄病毒嘌呤是由环氧亚胺合成的,环氧亚胺是由乙二醛异丁醛与受保护的α-溴-β-酮酰胺反应制得的。环氧酰亚胺的去保护作用和吡啶酮环的形成产生了(±)-黄素丙氨酸,通过热异构化将其转化为(±)-异黄素丙氨酸。