Selenocysteine (Sec) residue cannot be directly attached to a peptide sequence unless the selenol form is protected beforehand and several problems have been reported in the preparation of Sec building blocks. In this article a series of selenocystine, the oxidized form of Sec, containing peptides has been synthesized using a new methodology, where Boc-NH-chloroalanine is coupled with methyl ester protected residues (Ala, Met, Phe) using DCC/HOBt as the coupling reagents providing di- and tripeptides. Further, the treatment of disodium diselenide with chloroalanine peptides (Boc-ClAla-Ala-OMe, Boc-ClAla-Met-OMe and Boc-ClAla-Ala-Phe-OMe) afforded the respective selenocystine-containing peptides (Boc-Sec-Ala-OMe, Boc-Sec-Met-OMe and Boc-Sec-Ala-Phe-OMe).

中文翻译：

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硒肽的合成：并入硒代胱氨酸的另一种方法。

除非事先保护硒醇形式，并且在制备Sec结构单元中已报道了几个问题，否则硒代半胱氨酸（Sec）残基不能直接与肽序列相连。在本文中，已使用一种新方法合成了一系列硒代半胱氨酸（Sec的氧化形式），这些肽含有肽，其中Boc-NH-氯丙氨酸与甲酯保护的残基（Ala，Met，Phe）结合使用DCC / HOBt作为提供二肽和三肽的偶联剂。此外，用氯丙氨酸肽（Boc-ClAla-Ala-OMe，Boc-ClAla-Met-OMe和Boc-ClAla-Ala-Phe-OMe）处理二硒化二钠可分别得到含硒代半胱氨酸的肽（Boc-Sec-Ala -OMe，Boc-Sec-Met-OMe和Boc-Sec-Ala-Phe-OMe）。