Synthetic approach to (±)-vincamine via cleavage of an α-diketone monothioacetal. Alternative synthesis of (±)-eburnamine, (±)-isoeburnamine, and (±)-eburnamenine
作者:Seiichi Takano、Susumi Hatakeyama、Kunio Ogasawara
DOI:10.1039/p19800000457
日期:——
The half ester (8) prepared from cleavage of 2-(1,3-dithian-2-yl)-4-ethoxycarbonyl-4-ethylcyclohexanone (7) has been converted into (±)-eburnamine (20), (±)-isoeburnamine (21), and (±)-eburnamenine (22) by a stereospecific reaction sequence proceeding via the dithian intermediate (16). However an attempted conversion of (16) into (±)-vincamine (6) was unsuccessful.
由2-(1,3-二硫-2-基)-4-乙氧基羰基-4-乙基环己酮(7)的裂解制得的半酯(8)已转化为(±)-乙胺(20) -异异丁胺(21)和(±)-依伯南宁(22)的立体定向反应序列是通过二硫杂中间体(16)进行的。但是,尝试将(16)转化为(±)-长春胺(6)失败。