Lipase-catalyzed chemoselective n-acylation of amino-sugar derivatives in hydrophobic solvent: Acid-amine ion-pair effects
作者:Thierry Maugard、Magali Remaud-Simeon、Dominique Petre、Pierre Monsan
DOI:10.1016/s0040-4020(97)00450-x
日期:1997.6
citol) in hexane using lipase from Rhizomucor miehei (Lipozyme®) is described. N-methyl-glucamine was solubilized by oleic acid addition which resulted in the formation of an ion-pair between acid and amine function. This ion-pair, identified by Infra-Red spectroscopy, is essential for amide or ester synthesis. Its stability in hexane was also found to be the limiting factor of reaction yield which
酶促N-酰化在使用脂肪酶从己烷N-甲基葡糖胺(1-脱氧-1-甲基氨基d葡萄糖醇)的米赫根毛霉(的Lipozyme ®)进行了说明。N-甲基-葡糖胺通过添加油酸而溶解,这导致在酸和胺官能团之间形成离子对。通过红外光谱法鉴定的该离子对,对于酰胺或酯的合成是必不可少的。还发现其在己烷中的稳定性是反应产率的限制因素,其从未超过酸转化率的50%。油酸和N-甲基葡糖胺之间的反应对酰胺或酯合成的化学选择性在酸/胺比的控制下。这是第一份报告,显示了在非常规介质中操作酶催化时底物离子状态的关键作用。