摘要 |
<p>A peptide of the formula:wherein R1 represents His, Tyr, Trp or p-NH2-Phe, R2 represents Tyr or Phe, R3 represents an optionally substituted Gly or an optionally substituted alpha-D-amino acid residue, R4 represents Leu, Ile or Nle, R6 represents (1) Gly-NH-R7, wherein R7 represents a hydrogen atom or an alkyl group which may optionally be substituted with a hydroxyl group, or (2) NH-R8, wherein R8 represents a hydrogen atom, an alkyl group which may optionally be substituted with a hydroxyl group or an ureido group (-NH-CO-NH2), is produced advantageously in an industrial scale by reacting a peptide of the formula:wherein R1, R2 and R3 have the same meanings as defined above or its salts, with a peptide of the formula:wherein R4 and R6 have the same meaning as defined above and R5 represents Arg which has been protected or its salts, to produce a peptide of the formula:wherein R1, R2, R3, R4, R5 and R6 have the same meanings as defined above or its salt, and then subjecting thus obtained peptide (I') to a de-protecting group reaction.</p> |