A chemoenzymatic synthesis of the new angiotensin converting enzyme inhibitor CV-5975 (1) is described. The optically active key intermediate for the synthesis of 1, ethyl (R) -6- (1-benzyloxycarbonyl-4-piperidyl) -2-hydroxyhexanoate ((R) -4), was prepared by kinetic resolution of the racemic α-hydroxyester ((RS) -4) with a lipase and also by asymmetric reduction of the α-oxoester (3) with baker's yeast. The enantiomeric excess (ee) of the α-hydroxyester ((R) -4) produced by these enzymatic procedures exceeded 60%. This optically active alcohol ((R) -4) was converted to its mesylate ((R) -5), which was then subjected to SN2 reaction with the aminobenzothiazepine derivative (2) followed by deprotection to yield 1.
本文描述了一种新型
血管紧张素转换酶
抑制剂 CV-5975 (1) 的
化学合成方法。合成 1 的光学活性关键中间体(R) -6-(1-苄氧羰基-4-
哌啶基) -2-羟基
己酸乙酯((R) -4)是通过外消旋α-羟酯((RS) -4)与
脂肪酶的动力学解析以及α-氧酯(3)与面包酵母的不对称还原制备的。通过这些酶解方法制得的α-羟酯((R) -4)的对映体过量(ee)超过了 60%。这种具有光学活性的醇((R) -4)被转化为其
甲磺酸酯((R) -5),然后与
氨基苯并
硫氮杂卓衍
生物(2)发生 SN2 反应,再进行脱保护,得到 1。