The chemistry of peptides related to metabolites of Trichoderma spp. 2. An improved method of characterization of peptides of 2-methylalanine

• Published in: Canadian journal of chemistry Vol. 64; no. 1; pp. 164 - 173
• Main Authors: Shaw, I. M, Taylor, A
• Format: Journal Article
• Language: English
• Published: Ottawa, Canada NRC Research Press 01.01.1986; National Research Council of Canada
• Subjects: 2-methylalanine; Aminoacids, peptides. Hormones. Neuropeptides; Analytical, structural and metabolic biochemistry; Applied sciences; Biological and medical sciences; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Other techniques and industries; Proteins; Trichoderma; Fungi; Fungi Imperfecti; Peptides; Metabolite; Thallophyta
• ISSN: 0008-4042; 1480-3291
• DOI: 10.1139/v86-028

4-Chlorobenzoylazide reacts with amino acid and peptide esters to give the 4-chlorobenzoyl derivatives in 60-90% yield, at room temperature, without measurable racemization. The reaction also proceeds smoothly with hindered amines such as methyl 2-methylalaninate and with secondary amines, e.g. methyl L -prolyl- L -valinate. Ten examples of the reaction are reported with peptides, synthesized for the purpose, that might be accessible from hydrolysates of the numerous fungal metabolites now known, which contain a high proportion of 2-methylalanine. The derivatives of di-, tri-, tetra-, and pentapeptides were highly crystalline, with sharp melting points, and could be detected and integrated in the effluent from chromatography columns at about the 10-ng level. This simple method of derivatization might be usefully applied to the resolution of discrepancies in the physical properties of ostensibly the same 2-methylalanyl peptide prepared in different laboratories.