Methionine (Met) offers a valuable handle to achieve peptide chemical modification owing to its unique thioether functional group. In contrast with cysteine, the site-selective functionalization of the hydrophobic and redox-sensitive thioether motif on peptides is still challenging, and strategies for diversification on the Met residue are rarely disclosed. Herein we report a transition-metal-free and redox-neutral approach for Met diversification with substrate diversity, which could be applied to synthesize cyclic peptides.

中文翻译：

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以锍为关键中间体的蛋氨酸残基脱甲基烷基化

由于其独特的硫醚官能团，蛋氨酸 (Met) 为实现肽化学修饰提供了一种有价值的方法。与半胱氨酸相比，肽上疏水和氧化还原敏感的硫醚基序的位点选择性功能化仍然具有挑战性，并且很少公开 Met 残基多样化的策略。在这里，我们报告了一种无过渡金属和氧化还原中性方法，用于具有底物多样性的 Met 多样化，可用于合成环肽。