JPH051798B

57 There are disclosed a novel polypeptide represented by the formula shown below or its acid addition salt or complex:wherein Ala represents alanine, Ser serine, Leu leucine, Thr threonine, Val valine, Gly glycine, Lys lysine, Gln glutamine, Glu glutamic acid, His histidine, Tyr tyrosine, Pro proline, Arg arginine, Asp aspartic acid, and n represents an integer of 3 to 7. and a process for producing the same comprising forming a peptide or polypeptide represented by the above formula and subjecting the structural units containing a peptide residue represented by the formula:wherein R represents an active ester residue, Ala, Ser. Leu, Thr and n have the same meanings as defined above, formed in any step of the reaction to cyclization reaction.