作者:William T. Lambert、Gregory H. Hanson、Farid Benayoud、Steven D. Burke
DOI:10.1021/jo051479m
日期:2005.11.1
steps and 4% overall yield. In a separate route, 7 was also synthesized in 18 steps and 2% overall yield from a derivative of α-d-glucoheptonic acid γ-lactone (62). While the former route installs the fully elaborated C-ring endowed with the correct C12 stereochemistry early in the synthesis, the latter features a late-stage introduction of the C12 stereocenter during the ultimate one-pot Michael addition/ketalization
描述了两种到蛇绿蛋白B C1-C22亚基的有效途径。笼式缩酮7由18个步骤由(+)-conduritol E(27)组装而成,其中包含11个嵌入ABCDEF环框架内的不对称中心,总产率为4%。在单独的路线中,还通过18个步骤合成了7种化合物,由α - d-葡萄糖庚酸γ-内酯的衍生物合成的总收率为2%(62)。前一种方法在合成初期就安装了完全精巧的C环,并具有正确的C12立体化学,而后者则采用了在最终的一锅迈克尔加成/缩酮化级联反应中后期引入C12立体中心以形成CDE-的方法。笼的环形系统。通过比较这两种策略,讨论了C12立体中心对于关键缩酮化事件的重要性。