生物碱合成中的长链氨基甲酸酯。外消旋吲哚并啶209B及其(5 R *,8 S *,8a S *)-(±)非对映异构体的合成应用以及对(-)-吲哚唑烷209B的应用
摘要:
外消旋体(5 R *,8 R *,8a S *)-8-甲基-5-戊基吲哚并咪唑(吲哚并立定209B)(±)-1及其迄今未知的(5 R *,8 S *,8a S *)的合成非对映体(±)-20由8个步骤完成吡咯烷-2-硫酮 和 辛-2-烯酸乙酯。关键步骤包括利用衍生自乙烯基类氨基甲酸酯的亲核性进行环化反应(2 E)-{1- [1- [1-(2-羟乙基)己基]吡咯烷-2-亚乙基}乙酸乙酯 8,立体选择减少 双环乙烯基碳-碳双键的合成 氨基甲酸酯 11。对路线的对映体选择性修饰,涉及初始共轭加成(R)-(+)- N-苄基-1-苯基乙胺的阴离子与叔丁基(2E)-辛-2-烯酸叔丁酯的合成导致(-)-吲哚并啶209B的形式合成。
生物碱合成中的长链氨基甲酸酯。外消旋吲哚并啶209B及其(5 R *,8 S *,8a S *)-(±)非对映异构体的合成应用以及对(-)-吲哚唑烷209B的应用
摘要:
外消旋体(5 R *,8 R *,8a S *)-8-甲基-5-戊基吲哚并咪唑(吲哚并立定209B)(±)-1及其迄今未知的(5 R *,8 S *,8a S *)的合成非对映体(±)-20由8个步骤完成吡咯烷-2-硫酮 和 辛-2-烯酸乙酯。关键步骤包括利用衍生自乙烯基类氨基甲酸酯的亲核性进行环化反应(2 E)-{1- [1- [1-(2-羟乙基)己基]吡咯烷-2-亚乙基}乙酸乙酯 8,立体选择减少 双环乙烯基碳-碳双键的合成 氨基甲酸酯 11。对路线的对映体选择性修饰,涉及初始共轭加成(R)-(+)- N-苄基-1-苯基乙胺的阴离子与叔丁基(2E)-辛-2-烯酸叔丁酯的合成导致(-)-吲哚并啶209B的形式合成。
An Efficient Sequential Reaction Process to Polysubstituted Indolizidines and Quinolizidines and Its Application to the Total Synthesis of Indolizidine 223A
作者:Wei Zhu、Dapeng Dong、Xiaotao Pu、Dawei Ma
DOI:10.1021/ol047476y
日期:2005.2.1
The reaction of iodides 1 with delta-chloropropylamines 5 in MeCN assisted with K2CO3 undergoes a sequential S(N)2/Michael addition/SN2/SN2 reactionprocess to give polysubstituted indolizidines and quinolizidines. Using this method, indolizidine 223A is synthesized from 2-ethyl-2-hexenoic acid in 12 linear steps and 14.5% overall yield. [Reaction: see text]
A sequential reaction process to assemble polysubstituted indolizidines, quinolizidines and quinolizidine analogues
作者:Guorong Cai、Wei Zhu、Dawei Ma
DOI:10.1016/j.tet.2006.03.068
日期:2006.6
The omega-iodo-alpha,beta-alkynoates and their ketone, sulfone or phosphonate analogues react with delta-chloropropylamines in MeCN assisted with K2CO3 to undergo a sequential S(N)2/Michael addition/S(N)2/S(N)2 reaction process, giving polysubstituted indolizidines or quinolizidines in good to excellent yields. This sequential reaction process is also compatible with three other substituted alpha,beta-alkynoates, affording quinolizidine analogues in moderate to good yields. (c) 2006 Elsevier Ltd. All rights reserved.