标题: Toward sustainable solid-phase peptide synthesis strategy – in situ Fmoc removal

发表时间: 2024

发表作者: Ndumiso Mthethwa, K. P. Nandhini, Ashish Kumar, Anamika Sharma, Beatriz G. de la Torre, Fernando Albericio

发表机构:

• Peptide Science Laboratory, School of Chemistry and Physics, University of KwaZulu-Natal, Durban, South Africa
• KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), School of Laboratory Medicine and Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
• Department of Organic Chemistry, University of Barcelona, Barcelona, Spain

关键词: green chemistry, in situ coupling deprotection, peptide, 4-methylpiperidine, sustainable chemistry

ABSTRACT
Solid-phase peptide synthesis (SPPS) is the method of choice for the synthesis of peptides for research and production purposes. Despite having several positive features, it remains a challenge to reduce the amount of solvent waste generated during the synthesis. We proposed a 3-step protocol (in-situ Fmoc removal) where washing after coupling was eliminated. Here, the in-situ Fmoc removal protocol was optimized by adding an extra 4-methylpiperidine (4-MP) treatment to ensure the removal of the Fmoc. Additionally, a second addition of the  carbodiimide during the coupling step is performed to form an in situ more active ester of the Fmoc-amino acid. The number of washings has been kept to a minimum of three adding in two of them 1% of OxymaPure to ensure the total removal of the 4-MP. This strategy, which saves up to 60% of solvent, was successfully demonstrated in two important Active Pharmaceutical Ingredients (APIs), angiotensin II and afamelanotide synthesis, with high purity. This strategy will be added to the green toolbox of SPPS making the approach more sustainable.


摘要：
固相肽合成（SPPS）是合成研究和生产用肽的首选方法。尽管具有几个积极特征，但在合成过程中减少溶剂废物的生成仍然是一个挑战。我们提出了一种3步协议（原位Fmoc去除），其中消除了偶联后的洗涤步骤。在这里，通过添加额外的4-甲基哌啶（4-MP）处理来优化原位Fmoc去除协议，以确保去除Fmoc。此外，在偶联步骤中进行第二次加入碳二亚胺以形成原位更活跃的Fmoc-氨基酸酯。洗涤次数最少为三次，其中两次添加1%的OxymaPure以确保完全去除4-MP。这种策略可以节省高达60%的溶剂，并已成功应用于两种重要的活性药物成分（APIs），即血管紧张素II和阿法诺肽的合成，并且纯度很高。这一策略将被添加到SPPS的绿色工具箱中，使该方法更加可持续。