Patent ID: 7238775

Claim:
A cyclic somatostatin(SRIF) analog peptide which selectively binds the SRIF receptor SSTR4 in contrast to its affinity for SSTR1, SSTR2, SSTR3 and SSTR5, which peptide comprises the amino acid sequence (cyclo)Xaa 1 -Xaa 2 -Xaa 3 -Xaa 4 -Xaa 5 -Phe-Xaa 7 -Xaa 8 -Lys-Thr-Xaa 11 -Xaa 12 -Xaa 13 -Cys (SEQ ID NO:2) wherein Xaa 1 is des-Xaa, D-Ala, Ala, L-Hor, Cbm, an acyl group having up to 20 carbon atoms or alkyl(C 1 to C 6 ); Xaa 2 is Tyr, D-Tyr, Gly or des-Xaa; Xaa 3 is Cys or D-Cys; Xaa 4 is des-Xaa; Xaa 5 is des-Xaa; Xaa 7 is an amino acid selected from the group consisting of Ala, Aph, Amp, Iamp, and Val; Xaa 8 is an amino acid selected from the group consisting of (A)Trp, (A)D-Trp, and 2Nal, wherein A is H, Cl, F, Br, Me, NO 3 , OMe or formyl; Xaa 11 is Ala, Gly, Val, Phe or Tyr; Xaa 12 is des-Xaa; and Xaa 13 is des-Xaa.