aspartimide formation peptide synthesis Aspartimide formation remains one major hurdle during peptide synthesis - Aspartimide formationmass difference synthesis Mastering Aspartimide Formation in Peptide Synthesis: Strategies for Enhanced Purity and Yield

Aspartimidestructure Aspartimide formation is a well-documented and frequently encountered challenge in peptide synthesis, particularly within the realm of Fmoc solid-phase peptide synthesis (SPPS). This undesirable side reaction significantly compromises the purity and yield of synthesized peptides, necessitating robust strategies for its prevention and control. Understanding the mechanisms behind aspartimide formation is crucial for researchers and chemists aiming to achieve high-quality peptide products2022年6月9日—Aspartimide formation is still a serious challenge in peptide synthesis. This side reaction is strongly sequence dependent and preferably ....

The core issue lies in the inherent reactivity of the aspartic acid residue. When an aspartic acid residue is present in a peptide sequence, especially when followed by glycine (forming an Asp-Gly or DG sequence), it becomes highly susceptible to intramolecular cyclization.作者：K Sato·2024·被引用次数：8—Aspartimide formationis one of the major obstacles that impedes the solid phasesynthesisof largepeptidesand proteins. Until now, no cost- ... This process is often triggered by basic conditions, such as those employed during the Fmoc deprotection step using reagents like piperidine. During Fmoc deprotection, the amino group of the aspartic acid residue becomes deprotected, and the side-chain carboxyl group can then attack this newly liberated amine, forming a five-membered cyclic imide ring – the aspartimide intermediate作者：MJW Kong·2025·被引用次数：2—Aspartimide formation remains a persistent challenge in Fmoc solid phase peptide synthesis. This review surveys strategies to prevent aspartimide formation ....

This aspartimide formation is not merely a transient intermediate; it can lead to several detrimental consequences作者：JP Tam·1988·被引用次数：126—Factors affectingaspartimide formation, such as protecting groups, acidity, basicity, and temperature, were studied using the model tetrapeptide, .... Firstly, it can result in low yields, as the desired peptide bond formation is hindered. Secondly, the aspartimide can undergo further reactions, leading to the formation of undesired byproducts, such as isoaspartyl peptides作者：K Toney·1993·被引用次数：21—This cytosolic enzyme is known to preferentially methylate L-isoaspartyl residues within model substrates. Control experiments in which JP was incubated in the .... These impurities can be difficult and costly to remove, significantly impacting the overall efficiency of the peptide synthesis process. The presence of aspartimide formation can complicate the solid phase synthesis of peptides, particularly larger ones and proteins.作者：K Neumann·2020·被引用次数：80—Aspartimide formation leads to low yieldsin addition to costly purification or even inaccessible peptide sequences. Here, we report an ...

The search intent surrounding this topic highlights a clear need to comprehend the causes and solutions for aspartimide formation. Many researchers are looking to learn about aspartimide formation in peptide synthesis to effectively prevent it. Indeed, aspartimide formation remains a persistent challenge in Fmoc solid phase peptide synthesis, and it is often described as a notorious side reaction in peptide synthesis. The tendency for aspartimide formation is strongly sequence-dependent, with Aspartic Acid, Glycine (DG) being the most prone to cause aspartimide formation.Identification, occurrence and prevention of aspartimide ...

Fortunately, extensive research has yielded several effective strategies to mitigate and block aspartimide formation. One of the primary approaches involves modifying the protecting group strategy for the aspartic acid side chainAspartic Acid, Glycine (DG) is the most prone to cause aspartimide formation. Limiting the number of DG combos is a peptide can greatly simplify the .... Utilizing specific protecting groups that are less prone to activating the carboxyl group for cyclization can significantly reduce the incidence of aspartimide formation. For instance, employing sterically hindered protecting groups or those that require more stringent deprotection conditions can be beneficial.作者：D Flora·2005·被引用次数：31—In summary, we have demonstrated thataspartimide formation is predominant in the standard Fmoc peptide synthesisusing an allyl ester as the side chain ... The use of aspartic acid derivatives has been explored to achieve the minimization of base-catalyzed aspartimide formation during peptide synthesis.作者：K Neumann·2020·被引用次数：80—Aspartimide formation leads to low yieldsin addition to costly purification or even inaccessible peptide sequences. Here, we report an ...

Another critical aspect is the careful selection of coupling reagents and reaction conditions. Milder coupling reagents and optimized reaction times can minimize the exposure of aspartic acid residues to conditions that promote cyclization. Furthermore, the choice of base used for Fmoc deprotection plays a significant role. While piperidine is commonly used, exploring alternative deprotection agents or adjusting the concentration and reaction time can help reduce the extent of aspartimide formation. Some studies suggest that aspartimide formation is predominant in the standard Fmoc peptide synthesis when using an allyl ester as the side-chain protecting group.

The academic literature offers numerous publications detailing various approaches to tackle this issue. For example, some research focuses on incorporating a blocking group on the alpha-nitrogen of the amino acid preceding aspartic acid in the peptide synthesis. This can effectively prevent the cyclization.2023年2月6日—Aspartimide rearrangements are a particularly nasty side reaction thatcan occur during fmoc-based solid phase peptide synthesis. Another avenue involves strategies that restrict the ligation process in native chemical ligation (NCL) to minimize the formation of aspartimides and derived byproducts.A Systematic Comparison of Different Methods to Tackle ...

The mass difference associated with aspartimide formation can be a useful indicator for its detection and quantification using mass spectrometry.作者：K Toney·1993·被引用次数：21—This cytosolic enzyme is known to preferentially methylate L-isoaspartyl residues within model substrates. Control experiments in which JP was incubated in the ... Understanding the aspartimide structure and its potential for rearrangement is also vital for accurate analysis and characterization of synthesized peptides.

In summary, while aspartimide formation presents a significant hurdle in peptide synthesis, a comprehensive understanding of its mechanisms, coupled with the strategic implementation of appropriate protecting group chemistries, optimized reaction conditions, and careful reagent selection, allows chemists to overcome this challenge. By employing these advanced techniques, researchers can significantly enhance the purity and yield of their synthesized peptides, paving the way for more reliable and efficient peptide-based research and development作者：D Flora·2005·被引用次数：31—In summary, we have demonstrated thataspartimide formation is predominant in the standard Fmoc peptide synthesisusing an allyl ester as the side chain .... The continuous exploration of novel methodologies and reagents remains key to further improving the success rate of complex peptide synthesis.