The present invention provides a new approach to the synthesis of 2-amino-tetrahydrocarbazole-propanoic acid, a key intermediate for the synthesis of Ramatroban. More specifically, a synthesis of 2-amino-tetrahydrocarbazole- propanoic acid which includes oxidizing an aminocyclohexanol to form an aminocyclohexanone, condensing the aminocyclohexanone to form a tetrahydrocarbazole, deprotecting the tetrahydrocarbazole to yield a racemic mixture of a tetrahydrocarbazole, resolving the racemic mixture to obtain a yield mixture with an enantiomeric excess of one enantiomer over another, alkylating the excess enantiomer to yield an alkyl ester, and hydrolyzing the alkyl ester to yield 2-amino-tetrahydrocarbazole-propanoic acid.
本发明提供了一种合成2-
氨基-四氢
吲哚-
丙酸的新方法,这是合成Ramatroban的关键中间体。更具体地说,合成2-
氨基-四氢
吲哚-
丙酸的方法包括将
氨基
环己醇氧化形成
氨基
环己酮,将
氨基
环己酮缩合形成四氢
吲哚,去保护四氢
吲哚以得到一种四氢
吲哚的外消旋混合物,将外消旋混合物拆分以获得具有一种对映体过剩的混合物,烷基化过剩对映体以得到烷基酯,然后
水解烷基酯以得到2-
氨基-四氢
吲哚-
丙酸。