Application of reversible amide-bond protection to suppress peptide segment epimerisation
作者:John Offer、Tony Johnson、Martin Quibell
DOI:10.1016/s0040-4039(97)10431-2
日期:1997.12
Reversible alkylation of the C-terminal amide-bond of a protected peptide segment with 2-hydroxy-4-methoxybenzyl dramatically suppresses epimerisation during activation and coupling. However, due to the formation of a 4,5-dihydro-8-methoxy-1,4-benzoxazepin-2(3H)-one species upon activation the rate of coupling is low. A safety-catch amide-bond protecting group, 6-hydroxy-5-methyl-1,3-benzoxathiolyl
受保护的肽段的C末端酰胺键与2-羟基-4-甲氧基苄基的可逆烷基化显着抑制了活化和偶联过程中的差向异构。但是,由于在活化时形成了4,5-二氢-8-甲氧基-1,4-苯并恶嗪-2(3H)-一物质,因此偶联速率很低。设计了一种安全捕获的酰胺键保护基团6-羟基-5-甲基-1,3-苯并恶硫醇,可抑制差向异构化并具有出色的收率。