New Development of Enzyme Utilization in Organic Solvents

在脂肪酶Saiken 100的催化作用下，伯醇、仲醇和叔醇在有机介质中与三甲基硅基酮进行了有效的酰化反应，得到了三甲基硅乙酰酯。该酶还成功地酰化了苯酚和大体积醇以及带有羧基的底物。该酶还催化了三乙基硅基酮和二甲基苯基硅酮的酰化反应。双烯酮具有高度张力的四元环和分子内的烯醇酯结构，是脂肪酶在有机溶剂中催化醇的酰化反应的有效试剂。脂肪酶Amano PS的立体选择性很高，这否定了传统的蛋白质表面催化的观点。通过简单的分步蒸馏，可以很容易地分离出剩余的醇类和生成酯。具有相似结构的β-内酯还具有立体选择性的开环转酯化反应，是合成天然产物和生物可降解共聚物的重要原料。

By the catalytic action of a lipase, Saiken 100, primary, secondary, and tertiary alcohols were effectively acylated with trimethylsilylketene in organic media, to give trimethylsilylacetyl esters. The enzyme also successfully acylated a phenol and bulky alcohols as well as a substrate bearing a carboxyl group. The acylation with triethylsilylketene and dimethylphenylsilylketene was also catalyzed by the enzyme.Diketene having a highly strained 4-membered ring and intramolecular enol-ester structure was found to be a powerful acylating agent for lipase mediate acylation of alcohols in organic solvents. The stereoselectivity with a lipase, Amano PS,was extremely high which denied the conventional propose of the catalysis on the protein surface. The remaining alcohols and generated esters were able to be separated easily by simple fractional distilllation. beta-Lactones having the similar structure was also trans-esterified with ring opening stereoselectively which were very important starting materials for natural products synthesis and bio-degradable copolymers.