Patent ID: 6872803

Claim:
A peptide represented by the following formula (A): wherein X 1 represents an α-amino acid residue selected form the group consisting of Asn, Gln and His; X 2 represents an α-amino acid residue selected form the group consisting of Trp, Tyr and Phe; X 3 represents an α-amino acid residue selected form the group consisting of His, Asn and Gln; X 4 represents an α-amino acid residue selected form the group consisting GIy and Ala; X 5 represents an α-amino acid residue selected form the group consisting of Thr and Ser; X 6 represents an α-amino acid residue selected form the group consisting of Ala, Gly and Ser; M represents Gly or Cys; and n represents an integer of from 0 to 3, and Q is represented by a formula selected from the group consisting of formula (I), (II), (III) and (IV), wherein formula (I) is -(Y 1 )p 1 -Arg-Gly-Asp-(Z 1 )q 1 -W 1 (I) wherein Y 1 and Z 1 each represent an α-amino acid residue; W 1 represents a hydroxy, lower alkoxy or amino group; p 1 represents an integer of from 0 to 8; q 1 represents an integer of from 0 to 10; and the α-amino acid residues to be represented by Y 1 's when p 1 is 2 or more or by Z 1 's when q 1 is 2 or more are the same or different; formula (II) is -(Y 2 )p 2 -Cys-A 2 -B 2 -C 2 -W 2 (II) wherein A 2 , B 2 and C 2 each represent an α-amino acid residue; p2 represents an integer of from 0 to 8; Y 2 represents an α-amino residue; W 2 represents a hydroxy, lower alkoxy or amino group; and the α-amino acid residues to be represented by Y 2 's when p 2 is 2 or more are the same or different; formula (III) is -(Ala)p 3 -A 3 -B 3 -C 3 -Asp-B 3a -C 3a -D 3 -W 3 (III) wherein p 3 represents an integer of from 0 to 1; W 3 represents a hydroxy, lower alkoxy or amino group; A 3 represents Phe, Gly, Phe-Gly, Gly-Gly, Phe-Gly-Gly or a single bond; B 3 and B 3a are the same or different and each represents Arg or D-Arg; C 3 and C 3a are the same or different and each represents Ile or (N-methyl)Ile; D 3 represents Gly, Ala, Gly-Ala, Ala-Ala, Gly-Ala-Ala or a single bond; and formula (IV) is -A 4 -Arg-Pro-B 4 -Gly-Phe-C 4 -D-Phe-Leu-Arg-W 4 (IV) wherein A 4 represents Arg, D-Arg, or a single bond; B 4 represents a hydroxyproline or Pro; C 4 represents Ser or Cys; W 4 represents a hydroxy, lower alkoxy or amino group, or a pharmaceutically acceptable salt thereof.