A secretoglobin 3A2 type C (98–139) peptide was synthesized by native chemical ligation between ¹¹⁵Ile and ¹¹⁶Cys residues using Dawson’s linker. The peptide-N-acyl-benzimidazolinone-glycine amide, a C-terminal thioesters precursor, was provided from 3-amino-4-(methylamino)benzoic acid. In addition, an N-terminal cysteine fragment, the (116–139) peptide, was prepared by ordinary Fmoc-solid phase peptide synthesis. Native chemical ligation of the (98–115) fragment with the Dawson’s linker and the (116–139) peptide smoothly proceeded to give SCGB3A2 type C (98–139) peptide.

中文翻译：

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通过道森的天然化学连接合成分泌性珠蛋白3A2 C型（98–139）片段

通过使用Dawson接头在¹¹⁵ Ile和¹¹⁶ Cys残基之间进行天然化学连接，可以合成C型分泌球蛋白3A2（98-139）肽。由3-氨基-4-（甲基氨基）苯甲酸提供肽-N-酰基-苯并咪唑啉酮-甘氨酸酰胺，其为C-末端硫酯的前体。此外，通过常规的Fmoc-固相肽合成可以制备N端半胱氨酸片段（116-139）肽。（98-115）片段与Dawson's接头和（116-139）肽的天然化学连接顺利进行，得到了SCGB3A2 C型（98-139）肽。