The 2-chlorotrityl chloride (2-CTC) resin is one of the most frequently used and most versatile resins for the large-scale manufacture of peptides. As a part of our efforts in greening solid-phase peptide synthesis, here, we disclose an efficient procedure for the loading of the first amino acid onto the 2-CTC resin using the green solvent N-butylpyrrolidinone. By applying a design of experiment models, key critical process parameters such as amino acid equivalents and water content were identified. The results obtained suggest that the conditions found can be generalized and applied to any Fmoc-amino acid. Moreover, they serve as a starting point for the optimization of green resin loading.

中文翻译：

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缺失的环节：能够在 N-丁基吡咯烷酮中加载 2-氯代三甲基氯化物树脂作为绿色溶剂

2-氯三苯甲基氯 (2-CTC) 树脂是用于大规模生产肽的最常用和最通用的树脂之一。作为我们在绿色固相肽合成方面努力的一部分，在这里，我们公开了一种使用绿色溶剂N-丁基吡咯烷酮将第一个氨基酸负载到 2-CTC 树脂上的有效程序。通过应用实验模型设计，确定了关键的关键工艺参数，例如氨基酸当量和水含量。获得的结果表明，发现的条件可以推广并应用于任何 Fmoc-氨基酸。此外，它们可作为优化绿色树脂装载量的起点。