2-Methyltetrahydrofuran and cyclopentyl methyl ether for green solid-phase peptide synthesis

Area of Science:

• Green chemistry
• Organic synthesis
• Peptide chemistry

Background:

• Traditional solvents in peptide synthesis pose environmental and safety concerns.
• Developing sustainable alternatives is crucial for modern chemical research and industry.
• 2-Methyltetrahydrofuran (2-MeTHF) and Cyclopentyl methyl ether (CPME) are emerging as potentially greener solvent options.

Purpose of the Study:

• To evaluate 2-MeTHF and CPME as environmentally friendly alternatives for peptide synthesis.
• To assess the compatibility of these solvents with amino acid derivatives, coupling reagents, and resins.
• To determine the impact of these solvents on racemization and coupling efficiency.

Main Methods:

• Solubility tests for amino acid derivatives and coupling reagents in 2-MeTHF and CPME.
• Resin swelling studies using polystyrene and polyethylene glycol resins.
• Determination of racemization levels and coupling efficiencies during model peptide synthesis (Z-Phg-Pro-NH2 and Aib-enkephalin pentapeptide).

Main Results:

• 2-MeTHF demonstrated good solubility for key reagents and effective resin swelling.
• The combination of 2-MeTHF with DIC/OxymaPure resulted in minimal racemization during stepwise synthesis.
• Highest purity was achieved during solid-phase peptide synthesis (SPPS) of Aib-enkephalin pentapeptide using 2-MeTHF.

Conclusions:

• 2-MeTHF is a viable greener alternative solvent for peptide synthesis.
• The combination of 2-MeTHF with DIC/OxymaPure offers excellent control over racemization and purity.
• These findings support the adoption of greener solvents in peptide synthesis protocols.