We describe a simple and robust oxidation strategy for preparing N-terminal thiazolidine-containing peptide thioesters from peptide hydrazides. We find for the first time that l-thioproline can be used as a protective agent to prevent the nitrosation of N-terminal thiazolidine during peptide hydrazide oxidation. The thioproline-based oxidation strategy has been successfully applied to the chemical synthesis of CC chemokine ligand-2 (69aa) and omniligase-C (113aa), thereby demonstrating its utility in hydrazide-based native chemical ligation.

中文翻译：

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基于硫代脯氨酸的氧化策略从肽酰肼直接制备含N端噻唑烷的肽硫酯


我们描述了一种简单而稳健的氧化策略，用于从肽酰肼制备含 N 末端噻唑烷的肽硫酯。我们首次发现L-硫代脯氨酸可以作为保护剂来阻止肽酰肼氧化过程中N端噻唑烷的亚硝化。基于硫代脯氨酸的氧化策略已成功应用于CC趋化因子配体-2 (69aa)和omniligase-C (113aa)的化学合成，从而证明了其在基于酰肼的天然化学连接中的实用性。