Abstract: The present invention relates to a compound of formula (I) a N-oxide thereof, a pharmaceutically acceptable salt thereof, a stereochemically isomeric form thereof or a solvate thereof, wherein X represents N or CH; Y and Z each independently represent C(?O) or CH2 provided that at least one of Y and Z represents C(?O); R1 represents CH(R4)-aryl or CH(R4)-heteroaryl; R2 represents aryl2 or heteroaryl; R3 represents hydrogen; C1-4alkylcarbonyl; C1-6alkyl optionally substituted with C1-6alkyloxy, C1-6alkylthio, C1-6alkyloxycarbonyl or aryl1; provided that when Y and Z each represent C(?O), X represents CH, R3 represents hydrogen, R4 represents hydrogen, and R2 represents unsubstituted pyridyl or phenyl optionally substituted with one halo or with one C1-4alkyloxy or with one or two C1-4alkyl, then aryl in the definition of R1 is other than phenyl substituted with one halo or with one or two C1-4alkyl; and provided that when Y and Z each represent C(?O), X represents CH, R3 represents hydrogen, and R2 repres