Macrocyclization of linear peptides enabled by amphoteric molecules.

Area of Science:

• Organic Chemistry
• Peptide Chemistry
• Materials Science

Background:

• Cyclic peptides are valuable scaffolds for nanomaterials, imaging agents, and therapeutics due to their rigid conformations.
• Traditional laboratory synthesis of cyclic peptides from linear precursors faces thermodynamic and kinetic challenges, leading to low yields and poor selectivity.

Purpose of the Study:

• To develop a novel and efficient method for synthesizing cyclic peptides.
• To overcome the limitations of existing cyclic peptide synthesis methods.

Main Methods:

• Utilizing amphoteric amino aldehydes as key intermediates for cyclization.
• Employing alpha-amino acids or linear peptides as starting materials.
• Performing cyclizations at high molar concentrations (0.2 M).

Main Results:

• Achieved efficient synthesis of cyclic peptides in high yields and selectivities.
• Observed no epimerization or cyclodimerization side processes.
• Demonstrated the ability to perform late-stage structural modifications on the synthesized products.

Conclusions:

• Amphoteric amino aldehydes provide an effective strategy for the efficient synthesis of cyclic peptides.
• The method overcomes common challenges in cyclic peptide synthesis, offering high yields and selectivity.
• The resulting cyclic peptides are amenable to further structural diversification.