title: Synthesis of the C-terminal undeca- and protected docosapeptide of bovine insulin B-chain.
abstract: The synthesis of two C-terminal peptides of bovine insulin B-chain are described. Thus, insulin fragments (B9-30) and ( B20 -30) were synthesized using nitrobenzoylglycyl -poly-(oxyethylene) as the soluble support. 4-Carboxy-2-nitrobenzyl ester of Boc-alanine was coupled to glycyl-poly(oxyethylene) and the syntheses were continued employing symmetrical anhydrides of Boc-amino acids. The protected peptides were cleaved from the support by photolysis and were purified on silica gel and Sephadex LH-20. All the protecting groups of a sample of the undecapeptide were removed with liquid HF and the unprotected peptide was purified on CM-cellulose. The synthesized peptides were gas chromatographically tested for the racemization of the individual amino acids. The results indicated that no residue was significantly racemized .
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002942:Circular Dichroism; D007328:Insulin / Q000138:chemical synthesis*; D013058:Mass Spectrometry; D010446:Peptide Fragments / Q000138:chemical synthesis*; D013237:Stereoisomerism
chemical_list: D007328:Insulin; D010446:Peptide Fragments; C041902:insulin B (20-30); C041903:insulin B (9-30)