Toward Enantiomerically Pure β‑Seleno-α-amino Acids via Stereoselective Se-Michael Additions to Chiral Dehydroalanines

The first totally chemo- and diastereoselective 1,4-conjugate additions of Se-nucleophiles to a chiral bicyclic dehydroalanine (Dha) are described. The methodology is simple and does not require any catalyst, providing exceptional yields at room temperature, and involves the treatment of the corresponding diselenide compound with NaBH4 in the presence of the Dha. These Se-Michael additions provide an excellent channel for the synthesis of enantiomerically pure selenocysteine (Sec) derivatives, which pose high potential for chemical biology applications.

本文报道了首例硒亲核试剂与手性双环脱氢丙氨酸（Dha）发生完全化学选择性及非对映选择性的1,4-共轭加成反应。该合成方法简便无需催化剂，室温下即可获得优异产率，具体操作为在Dha存在下，用硼氢化钠（NaBH₄）处理相应的二硒化合物。此类硒代迈克尔加成反应为合成对映体纯的硒代半胱氨酸（Sec）衍生物提供了高效途径，这类衍生物在化学生物学领域具有极高应用潜力。