Synthesis of aspidospermidine alkaloids from 1,2,3,4-tetrahydrocarbazole: Total stereoselective synthesis of (±)-18-noraspidospermidine
作者:Anahí Urrutia、J.Gonzalo Rodríguez
DOI:10.1016/s0040-4020(99)00614-6
日期:1999.9
of the 1,2,3,4-tetrahydrocarbazol-4-one derivatives has been analysed and applied to the synthesis of (±)-18-noraspidospermidine (1b). This was synthesised, starting from 4-(1′,3′-dioxolan-2′-yl)cyclohexanone which was successively transformed to 3-methyl-3-(3′-nitropropyl)-1,2,3,4-tetrahydrocarbazol-4-one and to the imine tetracycle 13 by means of nickel boride catalyst. The reduction of 13 to the natural
已经分析了1,2,3,4-四氢咔唑-4-酮衍生物的反应活性,并将其用于合成(±)-18-去甲亚哌啶(1b)。从4-(1',3'-dioxolan-2'-yl)环己酮开始合成,然后依次转化为3-甲基-3-(3'-硝基丙基)-1,2,3,4-四氢咔唑-4-一和通过硼化镍催化剂连接至亚胺四环13。用该系统将13还原为天然的顺式D环连接。E环的构建是通过Pummerer型反应从顺式-7-甲苯磺酰基-1-苯基硫代乙酰胺衍生物17进行的通过氧化,然后进行分子内环化,脱硫和还原为1b。