The invention relates to compounds 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 to pharmaceutically acceptable acid addition salt, to a racemic mixture or to its corresponding enantiomer and/or optical isomers thereof. It has been found that the present compounds are oxytocin receptor agonists for the treatment of autism, stress, including post traumatic stress disorder, anxiety, including anxiety disorders and depression, schizophrenia, psychiatric disorders and memory loss, alcohol withdrawel, drug addiction and for the treatment of Prader-Willi Syndrom.本發明係關於下式之化合物，其中：R1 為羥基或胺基；R2 為第二丁基或異丁基；R3 為低碳數烷基、經羥基取代之低碳數烷基、-(CH2)2C(O)-NH2、-(CH2)3-NH2或-CH2-五員芳族雜環基；R4 為氫或低碳數烷基；R5 為氫或低碳數烷基；或R4及R5可與其所連接的N及C原子共同形成吡咯啶環(其係視情況經羥基或鹵素取代)、哌啶環或氮雜環丁烷環；R6 為氫、低碳數烷基、經羥基取代之低碳數烷基、-(CH2)2C(O)OH、-(CH2)2C(O)NH2、視情況經胺基或羥基取代之苄基、-CH2-五員芳族雜環基、吲哚基、-CH2-環烷基、環烷基、-(CH2)2-S-低碳數烷基或為-(CH2)1-4-NH2；R6’ 為氫或低碳數烷基；或R6與R6’共同組成環烷基；X為-C(O)-CHR-NR’-C(O)-；R/R’ 彼此獨立地為氫或低碳數烷基；m為2；o 為0或1；或關於其醫藥上可接受的酸加成鹽、關於其外消旋混合物或其對應對映異構體及/或其光學異構體。已發現本發明化合物為催產素受體激動劑，其係用於治療自閉症、壓力(包括創傷後壓力症)、焦慮(包括焦慮症及抑鬱症)、精神分裂症、精神疾病及失憶症、酒精戒斷、藥物成癮及用於治療普瑞德-威利(Prader-Willi)症候群。
