a-Tertiary amino acids are essential components of drugs and agrochemicals, yet traditional syntheses are step-intensive and provide access to a limited range of structures with varying levels of enantioselectivity. Here, we report the α-alkylation of unprotected alanine and glycine by pyridinium salts using pyridoxal (PLP)-dependent threonine aldolases with a Rose Bengal photoredox catalyst. The strategy efficiently prepares various a-tertiary amino acids in a single chemical step as a single enantiomer. UV–vis spectroscopy studies reveal a ternary interaction between the pyridinium salt, protein, and photocatalyst, which we hypothesize is responsible for localizing radical formation to the active site. This method highlights the opportunity for combining photoredox catalysts with enzymes to reveal new catalytic functions for known enzymes.

中文翻译：

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协同光酶催化可利用苏氨酸醛缩酶合成α-叔氨基酸


α-叔氨基酸是药物和农用化学品的重要组成部分，但传统的合成方法步骤密集，只能获得有限范围的具有不同对映选择性水平的结构。在这里，我们报道了使用吡哆醛（PLP）依赖性苏氨酸醛缩酶和玫瑰红光氧化还原催化剂，通过吡啶鎓盐对未保护的丙氨酸和甘氨酸进行α-烷基化。该策略在单个化学步骤中有效地制备各种α-叔氨基酸作为单一对映体。紫外可见光谱研究揭示了吡啶鎓盐、蛋白质和光催化剂之间的三元相互作用，我们假设这种相互作用将自由基形成定位到活性位点。该方法强调了将光氧化还原催化剂与酶结合以揭示已知酶的新催化功能的机会。