Patent ID: 8440793

Claim:
A substantially pure compound that selectively binds melanocortin 1 receptor (MC1R) but not MC3R, MC4R or MC5R, said compound comprising a polypeptide (SEQ ID NO:9) having the sequence: Xaa 1 Xaa 2 Xaa 3 Xaa 4 Xaa 5 Xaa 6 Xaa 7 Xaa 8 Xaa 9 Xaa 10 Xaa 11 Xaa 12 Xaa 13 , wherein Xaa 1 is D-Val, D-Ala or D-Lys; Xaa 2 is D-Pro, D-Ala or D-Lys; Xaa 3 is D-Lys, D-Orn, D-Nle, D-Ala or D-Lys; Xaa 4 is Gly, or D-Ala; Xaa 5 is D-Trp, Trp, D-3-benzothienyl-Ala, D-5-hydroxy-Trp, D-5-methoxy-Trp, D-Phe, or D-Ala; Xaa 6 is D-Arg, D-His, or D-Ala; Xaa 7 is D-Cha, D-Phe, Phe, D-4-fluoro-Phg, D-3-pyridyl-Ala, D-Thi, D-Trp, D-4-nitro-Phe, or D-Ala; Xaa 8 is D-His, His, D-Arg, Phe, or D-Ala; Xaa 9 is D-Glu, D-Asp, D-citrulline, D-Ser, or D-Ala; Xaa 10 is D-Met, D-buthionine, D-Ile, or D-Ala; Xaa 11 is D-Ser, D-Ile or D-Ala; Xaa 12 is D-Tyr, D-Ser, or D-Ala; and Xaa 13 is D-Ser or D-Ala; wherein no more than one Xaa 1-13 is D-Ala except when Xaa 1-3 are all D-Ala, and no more than one Xaa 1-13 is an L-amino acid; or a pharmaceutically acceptable salt thereof.