【作者】 王浩然；

【导师】 王磊；

【作者基本信息】 吉林大学 ， 生物化学与分子生物学， 2015， 硕士

【摘要】 随着酶学研究的不断深入，许多酶已经被报道能够催化多种类型反应，这种特性称为酶催化非专一性。由于酶具有催化效率高、反应条件温和、无毒等优点，因此，在有机合成中越发受到化学家重视。本论文通过探究脂肪酶催化非专一性来设计多组分串联反应，为较复杂化合物的合成提供一条环保且经济可行的途径。研究脂肪酶催化α,β-不饱和醛和活性亚甲基类化合物之间发生Knoevenagel缩合反应，该反应作为制备β-烯酮/烯酮酯类物质是非常经典的C-C成键反应。对影响该反应的因素进行了筛选和优化，包括酶源、溶剂、水含量、酶量等。并且发现不同的底物结构会导致酶对E/Z选择不同，通过空白及失活实验验证脂肪酶对该反应的重要性，简单阐述了该反应的催化机制。研究脂肪酶在2H-苯并吡喃衍生物合成中的的催化非专一性，由于2H-苯并吡喃衍生物具有非常高的药用价值，因此探讨利用生物催化法制备该化合物很有必要。这个过程考察了酶源、溶剂、水含量、反应温度及底物结构对酶促反应速率的影响，并通过一系列实验（空白实验、失活的PPL及BSA）来验证酶活性中心对该反应的重要性，简单阐述了该反应的催化机制。研究脂肪酶在苯并[g]色烯衍生物合成中的催化非专一性，苯并[g]色烯衍生物是非常重要的有机前体物质，我们研究的重点在于利用单一脂肪酶将多组分物质串联在一起得到这种相对复杂的结构。这个过程系统考察了影响该反应发生的各种因素(酶源、酶量、溶剂、水含量及反应温度)。并且研究了底物结构对酶促反应速率的影响，通过空白实验、失活的CSL及BSA来验证酶空间三维结构的重要性，简单阐述了该反应的催化机制。更多还原

【Abstract】 The catalytic promiscuity of numerous enzymes have been reported recentlywith the development of enzymology. It refers to the ability of an enzyme ofcatalyzing completely different types of reactions relative to the natural reaction.Enzyme promiscuity has attracted a growing interest for chemists, because enzymepossesses the intrinsic advantages such as high catalytic efficiency, mild reactionconditions, non-toxic, etc.. In this paper, we would research an environment-friendlyand economically feasible way for organic synthesis through exploring lipasepromiscuity.Knoevenagel condensation is a useful and widely C-C bond formation reactionemployed in producing β-enones/enoesters in organic synthesis. Lipase from porcinepancreas (PPL) was firstly used to catalyze Knoevenagel condensation betweenα,β-unsaturated aldehydes and active methylene compounds. The effect of reactionconditions including enzyme sources, solvents, water content, enzyme loading, etc.,was systematically tested. And we found that PPL exhibited Z/E selectivity accordingto the structure geometry and the reactivity of substrate. We proved that lipase wasresponsible for this reaction through the blank test and completely denatured enzymetest. The proposed mechanism of the lipase-catalyzed Knoevenagel condensationbetween α,β-unsaturated aldehydes was presented.Lipase from porcine pancreas (PPL) was firstly reported to catalyzed synthesisof substituted2H-chromenes by a three component reaction. It was essential toexplore it owing to their pharmacological activities. The effect of reaction conditionsincluding enzyme sources, solvents, water content, reaction tempreture and structureof substrates, was systematically tested. We proved that the spatial structure of theenzyme was responsible for this reaction through a series of reaction including blanktest, completely denatured enzyme and BSA test. The proposed mechanism of thelipase-catalyzed synthesis of substituted2H-chromenes by a three component reactionwas presented.The synthesis of benzo[g]chromene derivatives through a multicomponent reaction catalyzed by Candida sp. lipase (CSL) was reported for the first time.Benzo[g]chromene derivatives have been reported to be the very important precursors.The key point was that using a single lipase catalyzed a multicomponent reaction toobtain relatively complex structures. The effect of reaction conditions includingenzyme sources, solvents, water content, reaction tempreture and enzyme loading,was systematically tested. And we deliberated on effect of structure of substrates onthe synthesis of benzo[g]chromene derivatives. We proved that spatial structure of theenzyme was responsible for this reaction through a series of reaction including blanktest, completely denatured enzyme and BSA test. The proposed mechanism of thelipase-catalyzed synthesis of benzo[g]chromene derivatives through amulticomponent reaction was presented.更多还原