The γ-Phenacyl and γ-p-Nitrobenzyl Esters to Minimize Side Reactions during Treatment of Glutamyl Peptides with Hydrogen Fluoride-Anisole Mixture

• Published in: Chemical & pharmaceutical bulletin Vol. 25; no. 10; pp. 2613 - 2616
• Main Authors: SUZUKI, KENJI, SASAKI, YUSUKE, ENDO, NOBUYOSHI
• Format: Journal Article
• Language: English
• Published: The Pharmaceutical Society of Japan 1977
• Subjects: zinc in 90% AcOH
• ISSN: 0009-2363; 1347-5223
• DOI: 10.1248/cpb.25.2613

For the synthesis of peptide containing glutamic acid residue (s) by solid phase peptide synthesis, γ-phenacyl or γ-nitrobenzyl ester group, which is stable to anhydrous hydrogen fluoride (HF), was used as γ-carboxyl protecting group of glutamic acid to minimize the side reactions. The protected peptide resins were treated with HF-anisole mixture followed by deprotection of the γ-carboxyl protecting group under mild conditions. This strategy gave a satisfactory result without detectable side reactions in the preparations of two model dipeptides, H-Ala-Glu-OH and H-Asn-Glu-OH, by solid phase peptide synthesis.