Process Development of a Scaleable Route to (2<i>R</i>)-[3-(2-Aminopropyl)-1<i>H</i>-indol-7-yloxy]-<i>N,N</i>-diethylacetamide: A Key Intermediate for AJ-9677, a Potent and Selective Human and Rat β<sub>3</sub>-Adrenergic Receptor Agonist
作者:Hiroshi Harada、Akihito Fujii、Osamu Odai、Shiro Kato
DOI:10.1021/op0341869
日期:2004.3.1
attention on the nucleophilic substitution reaction of the indole Grignard reagent 12 with acid chlorides. At the outset of our synthesis, reaction of 12 with acetyl chloride as a simple acid chloride was examined. Treatment of 12generated from4 and methylmagnesium bromide with acetyl chloride in CH2Cl2 along with a small amount of Et 2O needed for methylmagnesium bromide under ice-cooling or at room temperature
(2R)-[3-(2-Aminopropyl)-1H-indol-7-yloxy]乙酸 (2) 是 AJ-9677 的左侧片段,它是一种有效且选择性的人和大鼠 3-肾上腺素能受体激动剂。在此,我们描述了从 7-苄氧基-1H-吲哚 (4) 合成相应的 N,N-二乙基乙酰胺衍生物 3 的可规模化合成路线的工艺开发。由 4 和甲基溴化镁生成的吲哚格氏试剂 12 与 N-Fmoc-D-丙氨酰氯 22 反应,然后在回流温度下在 MeCN 和 2-PrOH 的混合物中用 NaBH4 还原所得粗品 3-酰基吲哚 26随后用草酸处理得到N-脱保护产物的草酸盐,(2R)-3-(2-氨基丙基)-7-苄氧基-1Hindole [(R)-7],为结晶材料,产率为60%。在 Boc 基团对 (R)-7 进行 N-保护后,(2R)-3-[2-(Bocamino)丙基]-1H-吲哚30被氢化以提供(2R)-3-(2-氨