Yang Xiaoxiao, Lin Hao, Lu Wen, Wang Dexin
Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing City Key Laboratory of Active Substances Discovery and Drugability Evaluation, Beijing, China.
Protein Pept Lett. 2013 Feb;20(2):140-5. doi: 10.2174/092986613804725343.
The stability of Merrifield linker in Fmoc deprotection process was quantitatively investigated by establishing working curve of two major decomposition components from two resin bound dipeptide models. By sampling reaction solution and analyzing with RP-HPLC, decomposition rate was determined. The results indicated that either α-amino acid or β-amino acid anchored Merrifield linker was endurable for Fmoc strategy peptide synthesis in common de-Fmoc conditions such as 20% piperidine/DMF and 2% DBU/2% piperidine/DMF under room temperature treatments. However, Fmoc-deprotection with microwave assistance of α-amino acid anchored peptide resin with 20% piperidine/DMF more than 20 times or β-amino acid anchored peptide resin with 2% DBU/2% piperidine/DMF more than 30 times is not recommended. Feasibility of the proposed compatibility was verified by design and synthesis of a thymic humoral factor derived peptide via Fmoc strategy on Merrifield resin. Thus by choosing moderate de-Fmoc protocol, Merrifield resin is feasible for Fmoc strategy oligopeptide synthesis.
通过建立两种树脂结合二肽模型中两种主要分解成分的工作曲线，对梅里菲尔德连接体在Fmoc脱保护过程中的稳定性进行了定量研究。通过对反应溶液进行取样并用反相高效液相色谱法（RP-HPLC）分析，确定了分解速率。结果表明，无论是α-氨基酸还是β-氨基酸锚定的梅里菲尔德连接体，在室温处理下的常见脱Fmoc条件（如20%哌啶/二甲基甲酰胺（DMF）和2%二丁基脲（DBU）/2%哌啶/DMF）下，对于Fmoc策略的肽合成都是耐受的。然而，不建议对α-氨基酸锚定的肽树脂用20%哌啶/DMF进行超过20次的微波辅助Fmoc脱保护，或对β-氨基酸锚定的肽树脂用2%DBU/2%哌啶/DMF进行超过30次的微波辅助Fmoc脱保护。通过在梅里菲尔德树脂上采用Fmoc策略设计和合成一种胸腺体液因子衍生肽，验证了所提出的兼容性的可行性。因此，通过选择适度的脱Fmoc方案，梅里菲尔德树脂对于Fmoc策略的寡肽合成是可行的。
