Considering the fact that site-selective late-stage diversification of peptides and proteins remains a challenge for biochemistry, strategies targeting low-abundance natural amino acids need to be further developed. As an extremely oxidation-sensitive and low-abundance amino acid, methionine emerges as a promising target for chemo- and site-selective modification. Herein we report an efficient and highly selective modification on methionine residues by one-pot O- and N-transfer reaction, generating sulfoximine-modified peptides with near-perfect conversion within 10 min. Moreover, the great tolerance to other natural amino acids has been demonstrated in reactions with various peptide substrates. To demonstrate the generality of this protocol, we have modified natural peptides and obtained sulfoximination products with high conversion rates. This methodology provides a novel strategy as the expansion of the methionine-based peptide functionalization toolbox.

中文翻译：

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一种快速选择性甲硫氨酸氧化修饰策略

考虑到肽和蛋白质的位点选择性后期多样化仍然是生物化学的挑战，需要进一步开发针对低丰度天然氨基酸的策略。作为一种极度氧化敏感和低丰度的氨基酸，甲硫氨酸成为化学和位点选择性修饰的有前途的靶标。在此，我们报告了通过一锅 O-和 N-转移反应对甲硫氨酸残基进行高效和高选择性的修饰，在 10 分钟内生成亚砜亚胺修饰的肽，转化率近乎完美。此外，在与各种肽底物的反应中已经证明了对其他天然氨基酸的极大耐受性。为了证明该协议的普遍性，我们修改了天然肽并获得了具有高转化率的磺化产物。