Influence of Substrate Structure on PGA-Catalyzed Acylations. Evaluation of Different Approaches for the Enzymatic Synthesis of Cefonicid
作者:Marco Terreni、Joseph Gapesie Tchamkam、Umberto Sarnataro、Silvia Rocchietti、Roberto Fernández-Lafuente、José M. Guisán
DOI:10.1002/adsc.200404136
日期:2005.1
centre of PGA. The enzymatic acylation of these nuclei with R-methyl mandelate has been studied in order to evaluate different approaches for the enzymatic synthesis of cefonicid. The best results have been obtained in the acylation of 7-SACA. Cefonicid (8) was recovered from the reaction mixture as the disodium salt in 65% yield and about 95% of purity. Furthermore, through acylation of 7-ACA, a “one-pot”
研究了底物结构对大肠杆菌中动态控制的酰化反应中青霉素G酰基转移酶(PGA)催化性能的影响。特别地,已经考虑了合成速率(v s)与酰化酯的水解速率(v h1)之间的比率,评估了不同的β-内酰胺核对活性位点的亲和力。7-氨基头孢烷酸(7-ACA)和7-氨基-3-(1-磺甲基-1,2,3,4-四唑-5-基)硫甲基-3-头孢4-4-羧酸(7-SACA)对PGA的活性中心表现出良好的亲和力。这些核被R酶促酰化对扁桃酸甲酯进行了研究,以评估头孢烯酮酶促合成的不同方法。在7-SACA的酰化中已获得最好的结果。从反应混合物中以二钠盐的形式回收头孢烯酮(8),产率为65%,纯度为约95%。此外,通过7-ACA的酰化反应,从头孢菌素C开始,使用三种酶依次进行了“一锅法”化学酶合成:D-氨基酸氧化酶(DAO),戊二酰酰基化酶(GA)和PGA。分三步获得头孢烯二钠盐,避免了任何中间纯化,总产率为35%,纯度为约9