Referring to a cyclic Peptide of formula (i), wherein R1 is NH - C (= o) or C (= o) - NH R2 is H or CH2 R3 is (CH2) 2 - (CH2) W - CH3 - (CH2) Z - NH2, R4A, among others and r4c r4b are H C1 - C10 alkyl, Halo, Halo, C1 - C10 alkoxy, Oh, among others or (r6a R5 is o (n) R6B) r6a and R6B are H or c1-c4 alkyl R7 is H (or C = o - NH2) W is an integer from 0 to 5 X, Z and y is an integer from 1 to 5.Cyclic peptides are preferred: Cycle (AC ARG Glu ASN PHE (D - (-) - arg TRP ORN) - NH2 (SEQ ID no: 48), Cycle (AC ARG Glu GLN PHE (D - (-) - arg TRP ORN) - NH2 (SEQ ID no: 51), Cycle (AC ARG Glu ASN - D - (4 - (f) - Phe ARG TRP ORN) - NH2 (SEQ ID no: 74), among others. It also relates to a Pharmaceutical composition.These cyclic peptides have activity on Melanocortin Receptors and are useful in the treatment of Type 2 diabetes, hyperlipidemia, obesity, metabolic syndrome, Cardiac disorders, among othersREFERIDA A UN PEPTIDO CICLICO DE FORMULA (I), DONDE R1 ES NH-C(=O) O C(=O)-NH R2 ES H O CH2 R3 ES (CH2)2, -(CH2)w-CH3, -(CH2)z-NH2, ENTRE OTROS R4a, R4b Y R4c SON H, HALO, ALQUILO C1-C10-HALO, ALCOXI C1-C10, OH, ENTRE OTROS R5 ES OH O N(R6a)(R6b) R6a Y R6b SON H O ALQUILO C1-C4 R7 ES H O C(=O)-NH2 w ES UN ENTERO DE 0 A 5 x, z E y SON UN ENTERO DE 1 A 5. SON PEPTIDOS CICLICOS PREFERIDOS: Ac-Arg-CICLO(Glu-Asn-D-Phe(4-CN)-Arg-Trp-Orn)-NH2 (SEQ ID NO:48), Ac-Arg-CICLO(Glu-Gln-D-Phe(4-CN)-Arg-Trp-Orn)-NH2 (SEQ ID NO:51), Ac-Arg-CICLO(Glu-Asn-D-Phe(4-F)-Arg-Trp-Orn)-NH2 (SEQ ID NO:74), ENTRE OTROS. TAMBIEN ESTA REFERIDA A UNA COMPOSICION FARMACEUTICA. DICHOS PEPTIDOS CICLICOS TIENEN ACTIVIDAD SOBRE LOS RECEPTORES DE MELANOCORTINA Y SON UTILES EN EL TRATAMIENTO DE DIABETES, TIPO 2, SOBREPESO, SINDROME METABOLICO, HIPERLIPIDEMIA, TRASTORNOS CARDIACOS, ENTRE OTROS
