| 摘要 |
PURPOSE:In a reaction wherein a carboxyl component is condensed with a basic component using a dialkylcarbodiimide, to obtain the titled compound useful as a physiologically active substance in high yield, by adding a strong acid to a reaction system. CONSTITUTION:An amino acid shown by the formula (R is alkyl at 1- or 3- position of imidazole nucleus) or a partial peptide (e.g., consisting of amino acid such as pyroglutamic acid, etc.) having a C-terminal group is condensed with an amino acid (e.g., glutamic acid) having an N-terminal group or an liberated imino group or peptide in the presence of a strong acid (e.g., sulfuric acid) using a dialkylcarbodimide, to give a histidine-containing peptide derivative. The reaction is carried out in a solvent such as THF, etc. in the presence of about 0.01-2mol based on the basic component of the strong acid at -30-90 deg.C. The reaction speed is promoted, the yield is improved, and the racemization of histidine residue is suppressed. |
