Complementary Asymmetric Routes to (<i>R</i>)-2-(7-Hydroxy-2,3-dihydro-1<i>H</i>-pyrrolo[1,2-<i>a</i>]indol-1-yl)acetate
作者:Thomas O. Schrader、Benjamin R. Johnson、Luis Lopez、Michelle Kasem、Tawfik Gharbaoui、Dipanjan Sengupta、Daniel Buzard、Christine Basmadjian、Robert M. Jones
DOI:10.1021/ol303070k
日期:2012.12.21
the tricyclic indole (R)-2-(7-hydroxy-2,3-dihydro-1H-pyrrolo[1,2-a]indol-1-yl)acetate, an important synthon for a preclinical S1P1 receptor agonist, are reported. Route 1 employs a modified version of Smith’s modular 2-substituted indole synthesis as the key transformation. Route 2 involves a highly enantioselective CuH-catalyzed 1,4-hydrosilylation as the stereodefining step. Both routes can be performed
对三环吲哚(R)-2-(7-羟基-2,3-二氢-1 H-吡咯并[1,2 - a ]吲哚-1-基)乙酸酯(一种重要的合成子)的两种不同且可扩展的对映选择性方法报道了临床前S1P 1受体激动剂。路线1采用Smith的模块2取代的吲哚合成的修改版本作为关键转换。路线2涉及高度对映选择性的CuH催化的1,4-氢化硅烷化作为立体定义步骤。两种方法都可以在不进行色谱的情况下进行,以提供≥98%ee的三克多克量。