A process for preparing ethyl-α-(1-carboxy-ethyl)amino-γ-oxo-γ-phenylbutyrate, which comprises reacting an alkali metal salt, an alkaline earth metal salt or a quaternary ammonium salt of alanine with ethyl-β-benzoylacrylate and a process for preparing ethyl-α-(1-carboxyethyl)amino-γ-phenylbutyrate, which comprises catalytically reducing ethyl-α-(1-carboxyethyl)amino-γ-oxo-γ-phenylbutyrate.
According to the process of the present invention and by controlling the conditions of the Michael addition reaction or work-up thereof, (aS, 1S)-ethyl-α-(1-carboxyethyl)amino-γ-oxo-y-phenylbutyrate having the formula (I) can be prepared in an extremely high yield starting from low-priced trans-ethyl-β-benzoylacrylate or cis-ethyl-β-benzoylacrylate and a metal salt or a quaternary ammonium salt of (S)-alanine. Further, according to the process of the present invention, (αS,1s)-ethyl-α-(1-carboxyethyl)amino-γ-phenylbutyrate having the formula (III), which is an important intermediate compound for preparing angiotensin converting enzyme (ACE) inhibitory agents, can be prepared quite simply and efficiently.
一种制备乙基-α-(1-羧基-乙基)
氨基-γ-氧代-γ-苯基
丁酸盐的工艺,其包括碱
金属盐、碱土
金属盐或丙
氨酸的季
铵盐与乙基-β-苯甲酰基
丙烯酸酯反应、丙
氨酸的碱
金属盐、碱土
金属盐或季
铵盐与乙基-β-苯甲酰基
丙烯酸酯反应,以及制备乙基-α-(1-羧乙基)
氨基-γ-苯基
丁酸酯的工艺,该工艺包括催化还原乙基-α-(1-羧乙基)
氨基-γ-氧代-γ-苯基
丁酸酯。
根据本发明的工艺,通过控制迈克尔加成反应或其加成反应的条件,可以从价格低廉的反式-乙基-β-苯甲酰
丙烯酸酯或顺式-乙基-β-苯甲酰
丙烯酸酯和(S)-丙
氨酸的
金属盐或季
铵盐开始,以极高的产率制备具有式(I)的(aS, 1S)-乙基-α-(1-羧乙基)
氨基-γ-氧代-y-苯基
丁酸酯。此外,根据本发明的工艺,可以非常简单和高效地制备具有式(III)的(αS,1s)-乙基-α-(1-羧乙基)
氨基-γ-苯基
丁酸酯,它是制备
血管紧张素转换酶(ACE)
抑制剂的重要中间化合物。