Peptides as oxytocin agonists

A compound of formula

• wherein
• R1 is hydroxy or amino;
• R2 is sec-butyl or isobutyl;
• R3 is lower alkyl, lower alkyl substituted by hydroxy, —(CH2)2C(O)—NH2, —(CH2)3—NH2 or —CH2-five membered aromatic heterocyclic group;
• R4 is hydrogen or lower alkyl;
• R5 is hydrogen or lower alkyl;
• or
• R4 and R5 may form together with the N and C atom to which they are attached a pyrrolidine ring, optionally substituted by hydroxy or halogen, a piperidine ring or an azetidine ring;
• R6 is hydrogen, lower alkyl, lower alkyl substituted by hydroxy, —(CH2)2C(O)OH, —(CH2)2C(O)NH2, benzyl optionally substituted by amino or hydroxy, —CH2-five membered aromatic heterocyclic group, indolyl, —CH2-cycloalkyl, cycloalkyl, —(CH2)2—S— lower alkyl or is —(CH2)1-4—NH2;
• R6′ is hydrogen or lower alkyl;
• or
• R6 and R6′ are together cycloalkyl;
• X is —C(O)—CHR—NR′—C(O)—;
• R/R′ are independently from each other hydrogen or lower alkyl;
• m is 2;
• o is 0 or 1;
• or a pharmaceutically acceptable acid addition salt, a racemic mixture or its corresponding enantiomer thereof.