Large-Scale Asymmetric Synthesis of the 3,6,7,8-Tetrahydrochromeno[7,8-<i>d</i>]imidazole BYK 405879: A Promising Candidate for the Treatment of Acid-Related Diseases
作者:Andreas M. Palmer、Matthias Webel、Christian Scheufler、Dieter Haag、Bernd Müller
DOI:10.1021/op800177x
日期:2008.11.21
te instead of 1-[1-(2-methylphenyl)vinyl]pyrrolidine, a reagent that was difficult to prepare and possesses limited shelf life. The catalyst loading of the asymmetric hydrogenation step was reduced significantly from a S/C ratio of 100:1 to a S/C ratio of 2500:1 by benzyl protection of ketone 15. After the Mitsunobu cyclization, the removal of byproduct was easily accomplished through acid−base extraction
基于药物化学使用的方法(前手性酮15的不对称加氢和所得醇34的Mitsunobu环化),建立了钾竞争酸阻滞剂BYK 405879(8)的合成方法。优化了几个关键的反应步骤。前手性酮的合成是使用3-(2-甲基苯基)-3-氧代丙酸乙酯代替1- [1-(2-甲基苯基)乙烯基]吡咯烷来完成的,该试剂难于制备且保存期限有限。通过酮15的苄基保护,不对称加氢步骤的催化剂负载量从100:1的S / C比率显着降低到2500:1的S / C比率。。在Mitsunobu环化后,通过酸碱萃取可轻松完成副产物的去除,然后在琥珀酸存在下通过结晶获得纯BYK 405879(8)。