Fmoc-Asn(Trt)-Ser[Ψ(Me,Me)Pro]-OH | CAS 920519-33-1

Fmoc-Asn(Trt)-Ser[Psi(Me,Me)Pro]-OH | CAS 920519-33-1

Fmoc-Asn(Trt)-Ser[Psi(Me,Me)Pro]-OH, also written as Fmoc-Asn(Trt)-Ser[Ψ(Me,Me)Pro]-OH, is a pseudoproline dipeptide building block designed for Fmoc-based solid-phase peptide synthesis (SPPS).

The product provides a protected Asn-Ser motif in a preassembled dipeptide form. Its pseudoproline structure temporarily modifies the local conformation of the growing peptide chain and is commonly used in synthesis strategies where aggregation, limited resin solvation, or difficult chain elongation may affect peptide assembly.

During appropriate final acidic cleavage and deprotection, the pseudoproline structure can be converted back to the native serine residue. This makes the building block particularly useful in aggregation-prone peptide synthesis, difficult Fmoc-SPPS sequences, peptide route development, and process optimization.

Basic Information

Product Features

Pseudoproline Building Block for Asn-Ser Motifs

Fmoc-Asn(Trt)-Ser[Psi(Me,Me)Pro]-OH contains the Asn-Ser sequence in a protected pseudoproline form.

The temporary cyclic structure modifies the conformational behavior of the peptide chain during solid-phase synthesis. This feature makes pseudoproline dipeptides useful tools when conventional amino acid-by-amino acid assembly encounters sequence-dependent synthesis difficulties.

Designed for Aggregation-Prone Peptide Synthesis

As peptide chains grow on resin, certain sequences may develop intermolecular interactions or secondary structures that reduce accessibility to coupling and deprotection reagents.

The pseudoproline strategy is used to interrupt this tendency temporarily and may help improve chain accessibility during SPPS.

For this reason, the product can be evaluated in difficult peptide synthesis where Asn-Ser-containing regions are associated with:

• On-resin aggregation
• Reduced coupling performance
• Difficult Fmoc deprotection
• Limited resin solvation
• Complex crude peptide profiles

Actual performance depends on the complete peptide sequence, resin system, coupling chemistry, and process conditions.

Preassembled Asn-Ser Dipeptide

Instead of introducing Asn and Ser as two separate residues, this product provides them as a preformed protected dipeptide building block.

The approach can be useful during peptide route development when researchers are comparing sequential residue incorporation with short-fragment or pseudoproline-assisted synthesis strategies.

Reversible Pseudoproline Protection

The pseudoproline unit is intended as a temporary structural element during peptide assembly rather than a permanent modification of the final peptide.

Under suitable acidic cleavage and deprotection conditions, the pseudoproline ring can be converted back to the corresponding native serine residue, restoring the intended Asn-Ser sequence.

Research and Process Applications

Fmoc Solid-Phase Peptide Synthesis

Fmoc-Asn(Trt)-Ser[Psi(Me,Me)Pro]-OH can be incorporated as a specialized Fmoc-SPPS peptide building block when an Asn-Ser motif occurs in the target sequence.

After coupling the protected dipeptide to the growing peptide chain, standard Fmoc-based chain-extension procedures can continue according to the selected synthesis route.

Difficult Peptide Sequence Development

The product is particularly relevant for peptide chemists working with sequences that show poor behavior during conventional SPPS.

A pseudoproline-containing route can be evaluated alongside the standard synthesis route to compare parameters such as:

• Coupling performance
• Deprotection efficiency
• Resin behavior
• Crude peptide profile
• Impurity formation
• Downstream purification performance

This makes Asn-Ser pseudoproline dipeptides useful not only as synthesis reagents but also as tools in peptide process development.

Peptide Route Optimization

For development and scale-up projects, the decision to introduce a pseudoproline dipeptide should be based on the behavior of the complete target sequence.

Fmoc-Asn(Trt)-Ser[Psi(Me,Me)Pro]-OH can be evaluated when process teams are seeking alternative approaches to difficult chain elongation, aggregation-prone sequences, or inefficient residue-by-residue synthesis.

Fragment-Based Peptide Synthesis

As a preassembled protected dipeptide, the product can also be considered in fragment-based peptide synthesis strategies where short protected peptide segments are introduced as defined building blocks.

This approach may be useful when the synthesis route is being optimized for fewer individual coupling operations or improved control of a problematic sequence region.

Custom Synthesis Support

Shandong Juntai Pharmaceutical supports the supply and custom development of pseudoproline dipeptides, Fmoc-protected amino acids, protected peptide fragments, and peptide synthesis intermediates for R&D and process-development projects.

For projects involving difficult or aggregation-prone peptide sequences, technical requirements can be discussed around:

• Target pseudoproline structure
• Sequence-specific protected peptide fragments
• Purity and impurity specifications
• Analytical requirements
• Custom batch quantities
• Scale-up feasibility
• Repeat supply planning
• Customized packaging

For customers searching for a pseudoproline dipeptide supplier or custom peptide building block manufacturer, project feasibility can be evaluated according to the target structure, protecting-group strategy, required specification, and expected order volume.

FAQ

What information should I provide when requesting a quotation?

Please provide the required quantity, target purity or specification, destination country, packaging requirements, and any special analytical requirements. For repeat or scale-up projects, estimated future demand is also helpful for supply planning.

Can I purchase an evaluation quantity before moving to larger-scale procurement?

Evaluation quantities can be discussed according to current product availability and project requirements. This is particularly useful when assessing an Asn-Ser pseudoproline dipeptide in a new peptide synthesis route before larger-volume purchasing.

What analytical documentation can be provided?

Available batch documentation can include a Certificate of Analysis and relevant analytical results according to the agreed specification. Requirements for HPLC, MS, moisture, residual solvents, or other project-specific tests should be confirmed before order placement.

Can specifications be customized for peptide process-development projects?

Project-specific requirements can be evaluated according to technical feasibility. Customers may discuss target purity, impurity limits, analytical methods, moisture control, or other specification items when a standard catalogue specification does not fully meet process-development needs.

Can Juntai supply other pseudoproline dipeptides or protected peptide building blocks?

Yes. Juntai can evaluate custom synthesis requirements for pseudoproline dipeptides, Fmoc-protected amino acid derivatives, protected dipeptide fragments, and sequence-specific peptide intermediates. Providing the target structure or sequence, protection strategy, quantity, and required purity will help accelerate project assessment.

For research, process development, and industrial applications only. Product specifications and supply arrangements should be confirmed according to individual project requirements.