Pyrrolo[3,2-<i>e</i>][1,4]diazepin-2-one Synthesis: A Head-to-Head Comparison of Soluble versus Insoluble Supports
作者:Nicolas Boutard、Julien Dufour-Gallant、Philippe Deaudelin、William D. Lubell
DOI:10.1021/jo200424q
日期:2011.6.3
class of aryldiazepin-2-one scaffolds, the synthesis of pyrrolo[3,2-e][1,4]diazepin-2-ones on a support was explored starting from N-(PhF)-4-hydroxyproline and featuring an acid-catalyzed Pictet–Spengler reaction to form the diazepine ring. Three supports [Wang resin, tetraarylphosphonium (TAP) soluble support, and Merrifield resin] were examined in the synthesis of the heterocycle and exhibited different
芳基二氮杂-2-酮被称为“特权结构”,因为它们以高亲和力结合多种受体类型。为了开发新型的芳基二氮杂-2-酮骨架,从N开始探索在载体上的吡咯并[3,2- e ] [1,4]二氮杂-2-酮骨架的合成。-(PhF)-4-羟基脯氨酸,具有酸催化的Pictet-Spengler反应,形成二氮杂环。在杂环的合成中检查了三种载体[Wang树脂,四芳基phosph(TAP)可溶性载体和Merrifield树脂],它们表现出不同的优缺点。通过在温和条件下裂解树脂后鉴定中间体,Wang树脂被证明对探索性合成的优化有效。但是,Pictet-Spengler反应的酸性条件导致树脂结合材料过早损失。借助TAP载体可以通过TLC,RP-HPLC-MS直接监测反应,在某些情况下还可以进行NMR光谱分析,这有助于通过沉淀纯化中间体。然而,材料的不完全沉淀导致总收率低于固相法树脂收率。事实证明,Merrifield树脂对吡咯并[3