摘要:手性醇拥有独特的功能基团,它是构成具有手性的药物和各种具有手性的化学产品的必不可少的中间体。使用生物催化的方法构成手性醇的有利的方面有对环境无害,反应的条件不激烈,催化率较高等。本论文研究了埃切毕赤酵母细胞在水相反应体系中催化2-羟基苯乙酮还原为单一构型的羟基苯乙二醇的反应,系统考察了底物浓度、温度、添加剂及反应体系对酶催化活性和选择性的影响。发现在反应体系中加入不同的添加剂可以影响酶的活性和选择性,其中添加甲醇可以提高产物的光学纯度。经过系统优化得到的最佳反应条件为:底物浓度20mM、不添加或添加甲醇为最适添加剂,甲醇浓度为5%,最适反应pH值为6.5、最适反应温度为30℃,经过20小时反应,得到单一构型的羟基苯乙二醇的产率为99.9%,ee值为98.3%(未加添加剂时ee值为98.2%)。为进一步的研究“一锅煮”的化学-酶法去消旋化奠定了基础。24076
毕业论文关键词:手性醇;生物催化剂;不对称还原;手性药物
Chemo-enzymatic de-racemization of chiral diols
Abstract: Chiral alcohols with specific functional groups are important intermediates for the synthesis of chiral drugs and chiral chemicals. The synthesis of chiral alcohols by biocatalytic method has several advantages such as high catalytic efficiency, mild reaction conditions and environmental friendliness. In this thesis, we studied the reduction of 2-hydroxyphenyl ethanone to hydroxyphenyl glycol by whole cells of Pichia etchellsii in aqueous phase system, and the effect of substrate concentration, temperature ,additives on the enzyme activity and reaction system. It was found that adding different additives to the reaction system can affect enzyme activity and selectivity. After systematic optimization, the best reaction condition is the following: substrate concentration of 20mM, methanol was the most suitable additives,methanol concentration of 5%, the optimum pH value of 6.5, optimum temperature was 30 °C. After 20 hours of reaction, single configuration hydroxyphenyl glycol was obtained in 99.9% yield and 98.3% ee value (it was 98.2% in the system without additive). These results formed a basis for additional investigation of the chemo-enzymatic de-racemization of diols in “one-pot”.
Key Words:Chiral alcohols; biocatalyst; asymmetric reduction; chiral drugs
目 录
1 研究背景 1
1.1 手性合成研究的意义 1
1.1.1 手性合成在制药领域中的应用 1
1.1.2 手性合成在其他领域的应用 2
1.2 获得单一对映体的手性化合物的方法 2
1.2.1 手性源 2
1.2.2 不对称合成 2
1.2.3 外消旋体拆分 3
1.3 手性醇类化合物的研究现状 3
1.4 本课题研究的意义及思路 5
1.4.1 研究意义 5
1.4.2 研究思路 5
2 实验原理和流程 7
2.1实验原理 7
2.1.1选择性化学氧化的原理 7
2.1.2 生物催化羰基不对称还原原理 8
2.1.3 化学氧化偶合生物还原去消旋化原理 9
2.2 实验方案的确定 9
3 试验方法与材料 10
3.1 实验材料 10
3.1.1 菌种 10
3.1.2 培养基 10
3.1.3 主要试剂 10
3.1.4 主要仪器 12
3.2 试验方法 12
3.2.1 分析方法 12 手性二醇的化学-酶法去消旋化研究:http://www.youerw.com/yixue/lunwen_17408.html