Oxyma-based phosphates for racemization-free peptide segment couplings

Area of Science:

• Organic Chemistry
• Medicinal Chemistry
• Biochemistry

Background:

• Amide bond formation is crucial in peptide synthesis.
• Existing coupling reagents face limitations with N-acyl-protected amino acids and peptide segment couplings.
• Glyceroacetonide-Oxyma (1) shows promise as a peptide-forming additive.

Purpose of the Study:

• To develop a novel coupling reagent for challenging peptide synthesis scenarios.
• To evaluate the efficacy of Diethylphosphoryl-glyceroacetonide-oxyma (DPGOx) (3) in forming amide bonds.
• To assess DPGOx's utility in lactam formation and its purification profile.

Main Methods:

• Synthesis and characterization of Diethylphosphoryl-glyceroacetonide-oxyma (DPGOx) (3).
• Application of DPGOx in amide-forming reactions with N-acyl-protected α-amino acids.
• Utilizing DPGOx for segment couplings of oligopeptides.
• Testing DPGOx in lactam-forming reactions.

Main Results:

• DPGOx (3) demonstrated stability in aprotic solvents.
• Effective coupling of N-acyl-protected α-amino acids and oligopeptide segments was achieved using DPGOx.
• The reagent facilitated lactam formation under the reported conditions.
• Simple aqueous work-up allowed for easy removal of DPGOx and by-products.

Conclusions:

• DPGOx (3) is a versatile and effective coupling reagent for peptide synthesis, particularly for challenging substrates.
• The reagent's stability and ease of purification offer significant advantages over existing methods.
• DPGOx broadens the scope of efficient amide and lactam bond formation in organic synthesis.