The invention provides compounds of formula (I): wherein A and B represent the groups —(CH2)m— and —(CH2)n— respectively; R1 represents hydrogen or C1-6alkyl; R2 represents hydrogen, halogen, hydroxy, cyano, nitro, hydroxy C1-6alkyl, trifluoromethyl, trifluoromethoxy, C1-6alkyl, C1-6alkoxy, C1-6fluoroalkoxy, —(CH2)pC3-6cycloalkyl, —(CH2)pOC3-6cycloalkyl, —COC1-6alkyl, —SO2C1-6alkyl, —SOC1-6alkyl, —S—C1-6alkyl, —CO2C1-6alkyl, —CO2NR5R6, —SO2NR5R6, —(CH2)pNR5R6, —(CF)pNR5COR6, optionally substituted aryl ring, optionally substituted heteroaryl ring or optionally substituted heterocyclyl ring; R3 represents optionally substituted aryl ring or optionally substituted heteroaryl ring; R4 represents hydrogen, hydroxy, C1-6alkyl, C1-6alkoxy, trifluoromethyl, trifluoromethoxy, halogen, —OSO2CF3, —(CH2)pC3-6cycloalkyl, —(CH2)qOC1-6alkyl or —(CH2)pOC3-6cycloalkyl; R5 and R6 each independently represent hydrogen, C1-6alkyl or, together with the nitrogen or other atoms to which they are attached, form an azacycloalkyl ring or an oxo-substituted azacycloalkyl ring; Z represents —(CH2)rX— wherein the —(CH2)r— group is attached to R3, or —X(CH2)r— wherein X is attached to R3, and wherein any of the —CH2— groups may be optionally substituted by one or more C1-6alkyl groups; X represents oxygen, —NR7 or —CH2— wherein the —CH2— group may be optionally substituted by one or more C1-6alkyl groups; R7 represents hydrogen or C1-6alkyl; m and n independently represent an integer selected from 1 and 2; p independently represents an integer selected from 0, 1, 2 and 3; q independently represents an integer selected from 1, 2 and 3; r independently represents an integer selected from 0, 1, and 2; or a pharmaceutically acceptable salt or solvate thereof. The compounds are useful in therapy, in particular as antipsychotic agents.