Total synthesis of Amaryllidaceae alkaloids, (+)-vittatine and (+)-haemanthamine, starting from d-glucose
作者:Masahiro Bohno、Kazuteru Sugie、Hidetoshi Imase、Yusralina Binti Yusof、Takeshi Oishi、Noritaka Chida
DOI:10.1016/j.tet.2007.05.041
日期:2007.7
The stereoselective total synthesis of (+)-vittatine 1 and (+)-haemanthamine 2 starting from d-glucose is described. The cyclohexene ring in 1 was prepared in an optically active form from d-glucose using Ferrier's carbocyclization reaction, and the critical quaternary carbon was stereoselectively generated via chirality transfer by the Claisen rearrangement of cyclohexenol 6. The hexahydroindole skeleton
描述了从d-葡萄糖开始的(+)-vittatine 1和(+)-manmanthamine 2的立体选择性全合成。使用Ferrier的碳环化反应,由d-葡萄糖以旋光形式制备1中的环己烯环,然后通过环己烯醇6的克莱森重排通过手性转移立体选择性地生成关键的季碳。六氢吲哚骨架是通过分子内氨基汞分解14,然后经Chugaev反应生成16来有效构建的。最后,Pictet-Spengler反应完成了(+)-vittatine 1的首次手性合成。另一方面,酯5的α-羟基立体选择性地进行,得到α-羟基酯19,向其引入氨基官能团以提供4。类似的4的转化,如用于合成维生素A所提供的(+)-manemanthamine 2。