Tetrahydropyranyl Backbone Protection for Enhanced Fmoc Solid-Phase Peptide Synthesis

Area of Science:

• Organic Chemistry
• Biochemistry
• Materials Science

Background:

• Fmoc solid-phase peptide synthesis is crucial for peptide and API manufacturing.
• Aggregation and solubility issues limit the synthesis of peptides longer than 40 amino acids.
• Existing backbone protecting groups like benzyl and pseudoproline have limitations.

Purpose of the Study:

• To evaluate the tetrahydropyranyl (Thp) group as an acid-labile alternative to benzyl protecting groups.
• To improve the efficiency of solid-phase peptide synthesis for aggregation-prone sequences.

Main Methods:

• Introduction of Thp-protected dipeptides onto the resin-bound peptide chain.
• Acid-labile cleavage and scavenging of the Thp group post-synthesis.
• Assessment of Thp group's efficacy in synthesizing amyloid-β and prion-derived peptide fragments.

Main Results:

• Thp groups significantly enhance the solid-phase assembly of aggregation-prone peptide fragments.
• Efficient introduction and cleavage of Thp groups were demonstrated.
• Drastic improvements in synthesizing challenging peptide sequences were observed.

Conclusions:

• Thp is a valuable, acid-labile backbone protecting group for solid-phase peptide synthesis.
• Thp-protected dipeptides are promising building blocks for peptide manufacturing.
• This strategy complements existing methods for overcoming peptide synthesis limitations.