Investigation on the chemoenzymatic synthesis of threo- and erythro-β-hydroxy-l-glutamic acid derivatives
作者:Francesca Sagui、Carlo De Micheli、Gabriella Roda、Pietro Magrone、Rachele Pizzoli、Sergio Riva
DOI:10.1016/j.molcatb.2011.11.004
日期:2012.3
of the malonic semialdehyde was transformed by means of a bioconversion catalyzed by the enzyme l-threonine aldolase from E. coli into a 6:4 epimeric mixture of two precursors of β-hydroxy glutamic acid. The enzyme was selective for the formation of the (S)-configuration at C-2, whereas the configuration at C-3 was not controlled. The two epimers were separated exploiting a diastereoselective acylation
丙二醛半醛的衍生物通过酶I-苏氨酸醛缩酶催化的生物转化从大肠杆菌转化为两种β-羟基谷氨酸前体的6:4差向异构体混合物。该酶对形成(S)-C-2处的配置,而C-3处的配置不受控制。利用脂肪酶PS催化的有机溶剂中的非对映选择性酰化作用分离了两种差向异构体。在Kazslauskas提出的脂肪酶PS的立体偏好模型的基础上,并通过比较两个同系物的H-2和H-3质子的化学位移,初步确定了产物的相对和绝对构型。证明了通过常规化学反应将获得的产物转化为β-羟基谷氨酸衍生物的可能性。