Hetero Diels−Alder Synthesis of 3-Hydroxypyridines: Access to the Nosiheptide Core
作者:Jin-Yong Lu、Hans-Dieter Arndt
DOI:10.1021/jo0703505
日期:2007.5.1
lead to the formation of the 6-isomer with exceptional regioselectivity (>95:5). This methodology was applied to a scaleable synthesis of the core structure of the potent antibiotic nosiheptide. Protecting groups were optimized, which led to a racemization-free seven-step synthesis of the key building block.
研究了甲硅烷基化烯醇肟与炔烃的1-氮杂二烯杂Diels-Alder反应,并对其进行了优化,以一种简单的操作即可高产率提供2,5,6-三取代的3-羟基吡啶。重要的是,发现单取代的炔基酮可导致以极高的区域选择性(> 95:5)形成6-异构体。该方法学应用于强效抗生素诺西肽核心结构的规模化合成。保护基团得到了优化,这导致关键构件的无消旋七步合成。