The present invention discloses a compound of formula (I): wherein: R1 is an aryl or heteroaryl ring; R2 is hydroxy, C1-6 alkoxy, C1-6 alkyl, amino, NR′R″ or C1-6 alkyl-NR′R″ where R′ and R″ are independently chosen from hydrogen and C1-4 alkyl and where R′ and R″, together with the nitrogen atom to which they are attached, form a saturated nitrogen-containing 3-7 membered heterocycle optionally containing a further nitrogen atom and optionally substituted by NR′R″ as defined above or R2 is C1-6 alkoxy substituted by NR′R″ as defined above; R3 is hydrogen or C1-6 alkyl; R4 is hydrogen, C1-8 alkyl, C2-8 alkenyl, C2-8 alkynyl, C3-8 cycloalkyl, aryl or aryl C1-6 alkyl; R5 is hydrogen, C1-8 alkyl, C2-8 alkenyl, C2-8 alkynyl, C3-8 cycloalkyl, aryl, aryl C1-6 alkyl or C1-6 alkoxycarbonyl; or R4 and R5, together with the nitrogen atom to which they are attached, form a C3-C10 mono- or bicyclic saturated ring; X and Y are independently chosen from hydrogen, hydroxy, nitro, amino, cyano, CF3, halogen and C1-4 alkyl; or a pharmaceutically acceptable salt thereof; as NK-2/NK-3 ligands for treating schizophrenia, COPD, asthma or irritable bowel syndrome.