Albericio F, Andreu D, Giralt E, Navalpotro C, Pedroso E, Ponsati B, Ruiz-Gayo M
Department of Organic Chemistry, University of Barcelona, Spain.
Int J Pept Protein Res. 1989 Aug;34(2):124-8. doi: 10.1111/j.1399-3011.1989.tb01500.x.
The protection of the thiol function of cysteine with the 3-nitro-2-pyridylsulfenyl (Npys) group has been successfully applied in the solid phase synthesis of nine peptides. A reexamination of the chemical stability of the protecting group has shown that, while Npys is essentially suitable for standard Boc/benzyl synthesis conditions, it is inadequate for the Fmoc strategy. Its proven stability to "high" HF acidolysis can not be extended to "low-high" conditions without significant thiol deprotection. On the other hand, the Npys group is quite compatible with standard photolytical cleavage conditions. The stability of Npys to HF and its thiol-activating character allow its application in peptide-carrier protein conjugation reactions by specific coupling through cysteine residues in the peptide.
用3-硝基-2-吡啶基亚磺酰基（Npys）基团保护半胱氨酸的硫醇官能团已成功应用于9种肽的固相合成。对该保护基团化学稳定性的重新研究表明，虽然Npys基本上适用于标准的Boc/苄基合成条件，但它不适用于Fmoc策略。其已证实的对“高”HF酸解的稳定性不能扩展到“低-高”条件而不发生显著的硫醇脱保护。另一方面，Npys基团与标准的光解切割条件相当兼容。Npys对HF的稳定性及其硫醇活化特性使其能够通过肽中半胱氨酸残基的特异性偶联应用于肽-载体蛋白偶联反应。
