作者:Michael T. Crimmins、Rima S. Al-awar、Isabelle M. Vallin、W. Gary Hollis、Rosemary O'Mahony、John G. Lever、Danute M. Bankaitis-Davis
DOI:10.1021/ja961071u
日期:1996.1.1
The enantioselective total synthesis of the potent antiparasitic agent milbemycin D (1) has been achieved. The spiroketal fragment is prepared through a novel spiroketalization of a hydroxy pyrone to set the anomeric stereocenter and establish functionality for the stereocontrolled attachment and subsequent extension of the connecting chain between the spiroketal and the hexahydrobenzofuran fragment
已经实现了强效抗寄生虫剂米尔倍霉素 D (1) 的对映选择性全合成。螺缩酮片段是通过羟基吡喃酮的新型螺缩酮化来制备的,以设置异头立体中心并建立螺缩酮和六氢苯并呋喃片段之间连接链的立体控制连接和后续延伸的功能。六氢苯并呋喃片段是通过利用顺序亲电环化-[2,3]-sigmatropic 重排关闭含氧环并结合 C5 羟基来构建的。溴化锂加速 Wittig 烯化以高产率在 C10,11 双键处连接含螺缩酮的亚基和六氢苯并呋喃亚基。C1 羟基的后续氧化提供了对 seco 酸的访问,顺利地进行大环内酯化。敏感的 C2 立体化学和 C3,4 双键的结合没有在 C2 或迁移...