Aggregation during Peptide-Chain Elongation and Solvents for Its Minimization

4 AGGREGATION DURING PEPTIDE-CHAIN ELONGATION AND SOLVENTS FOR ITS MINIMIZATION 

A completely different tactic is the use of microwave energy absorption of this energy by a peptide results in decreased aggregation. Lithium salts facilitate the solution of peptides in these polar solvents, increase the rate of swelling of polar resins, and improve coupling yields. Sometimes the order of addition of two solvents to a peptide makes a difference. The inclusion of pyridine can also have a beneficial 

C Reichardt. Solvent effects in organic chemistry. Verlag Chemie, Weinheim, 1979, p 242. 

WA Klis, JM Stewart. Chaotropic salts improve SPPS coupling reactions, in JR Rivier, GR Marshall, eds. Peptides Chemistry, Structure, and Biology. Proceedings of the 11th American Peptide Symposium. Escom, Leiden, 1990, pp 904-906. 

A Thaler, D Seebach, FC Cardinaux. Lithium-salt effects in peptide synthesis. Part II. Improvement of degree of resin swelling and efficiency of coupling in solid-phase synthesis. Helv ChimActa 74, 628, 1991. 

---