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Published on: August 1, 2018
Azo cyclization: peptide cyclization via azo bridge formation
1Department of Organic Chemistry, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
Summary
A novel azo cyclization method efficiently creates cyclic peptides in solution. This facile technique yields pure products, expanding peptide synthesis options.
Area of Science:
- Organic Chemistry
- Peptide Chemistry
- Medicinal Chemistry
Background:
- Peptide cyclization is crucial for drug development and biological studies.
- Existing cyclization methods can be complex and yield-limited.
- Novel, efficient cyclization strategies are needed.
Purpose of the Study:
- To introduce a new method for peptide cyclization in solution using azo bridge formation.
- To demonstrate the versatility and efficiency of this novel azo cyclization technique.
- To synthesize and characterize new cyclic azo peptides.
Main Methods:
- Linear peptide precursors containing para-amino-phenylalanine (Pap) and tyrosine or histidine residues were synthesized.
- Diazotization of Pap residues in acidic media.
- Intramolecular azo cyclization in mild basic media to form the cyclic peptide.
Main Results:
- Successful synthesis of 10 new cyclic azo peptides.
- High yields and purity of the synthesized cyclic peptides.
- Demonstration of the method's applicability to various peptide sequences.
Conclusions:
- Azo cyclization is a facile and efficient new method for peptide cyclization in solution.
- This method offers a valuable addition to the peptide synthesis toolbox.
- The synthesized cyclic azo peptides may have potential applications in various fields.
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