碳酸酯把手改构Wang树脂及其性能

Carbonate Handle Modified Wang Resin and Its Function

基于碳酸酯结构易于亲核脱除的原理,使用氯甲酸氯甲酯改构Wang树脂,并探究了改构树脂与首位氨基酸的缩合效率.实验结果表明,改构后的Wang树脂与20种Fmoc保护氨基酸均能达到70%以上的缩合效率;且对于带有较大侧链基团的Fmoc保护氨基酸,通过降低树脂取代度或延长反应时间可提高其连接率.为了验证改构后的碳酸酯型树脂在裂解时侧链未受到影响,设计合成了3种模型肽,并用温和裂解剂3-吡啶甲醛肟铯盐进行裂解.实验结果表明,利用改构树脂能得到侧链全保护的肽片段,可初步应用到长链困难肽的合成中.

Because of the carbonate structure is removed by nucleophilic agents easily, methyl chloroformate was used to modify Wang resin, and the condensation efficiency of modified Wang resin with the first amino acid was studied. The results showed the condensation efficiency of the modified resin to 20 kinds of Fmoc amino acids could run up to 70%. In order to increase the condensation efficiency of the modified resin with the Fmoc amino acids achieving larger side chain groups, the degree of resin substitution was reduced and the reaction time was prolonged. In order to prove the protected side chain group would not be damaged under cleavage conditions of the modified Wang resin, three model peptides were resigned and synthesized, and cleaved by 3-pyridinecarboxaldehyde sulfonium salt. The results showed that the peptides with side chain fully protected could be obtained by using the modified Wang resin, and could also be preliminary applied to the synthesis of long-chain peptides.