The invention relates to compounds of formula (I) wherein R1 is (A), or is phenyl, pyridinyl or pyridazinyl, wherein phenyl, pyridinyl and pyridazinyl may optionally be substituted by cyano, lower alkyl, halogen-substituted phenyl, lower alkyl-substituted [1,2,4]oxadiazol-3-yl or by 2-oxo-piperidin-1-yl X is NR or O R is C(O)-lower alkyl, -C(O)-cycloalkyl substituted by lower alkyl, cycloalkyl or is phenyl, pyridinyl or pyridazinyl, wherein phenyl, pyridinyl and pyridazinyl may optionally be substituted by lower alkyl, lower alkoxy, cyano, -C(O)-lower alkyl, halogen or lower alkyl substituted by halogen R2 is hydrogen or lower alkyl R3 is hydrogen, halogen, cyano, lower alkyl or lower alkyl substituted by halogen R4 is hydrogen or lower alkyl wherein R2 and R4 are not simultaneously hydrogen or lower alkyl R5 is lower alkyl R6 halogen, hydroxy, lower alkyl, lower alkoxy, lower alkyl substituted by halogen, S(O)2-lower alkyl or cyano or to a pharmaceutically suitable acid addition salt thereof. It has been found that the present compounds are high potential NK-3 receptor antagonists for the treatment of depression, pain, psychosis, Parkinsons disease, schizophrenia, anxiety and attention deficit hyperactivity disorder (ADHD).La presente invención se refiere a los compuestos de la fórmula (I) en donde R1 es (A) o es fenilo, piridinilo o piridazinilo, en donde fenilo, piridinilo y piridazinilo pueden ser sustituidos opcionalmente por ciano, alquilo inferior, fenilo sustituido con halógeno, [1,2,4]oxadiazol-3-ilo sustituido por alquilo inferior o por 2-oxo-piperidin-1-ilo X es NR u O R es -C(O)-alquilo inferior, -C(O)-cicloalquilo substituido por alquilo inferior, cicloalquilo o es fenilo, piridinilo o piridazinilo, en donde fenilo, piridinilo y piridazinilo pueden estar sustituidos opcionalmente por alquilo inferior, alcoxi inferior, ciano, -C(O)-alquilo inferior, halógeno o alquilo inferior substituido por halógeno R2 es hidrógeno o alquilo inferior R3 es hidrógeno, h
