3-((Hetero)arylsulfonyl)-8-'(aminoalkyl)oxyquinolines as 5-ht6 receptor antagonists for the treatment of cns disorders

A compound of formula (I) or a pharmaceutically acceptable salt thereof:

• wherein:
• R1 represents a group of formula —NRaRb or a nitrogen containing heterocyclyl group optionally substituted by one or more (eg. 1 to 4) C1-6 alkyl groups;
• X represents a bond, —(CRcRd)—, —(CRcRd)—(CReRf)—, —(CRcRd)—(CReRf)—(CRgRh)—, or -heterocyclyl-, wherein said heterocyclyl group may be optionally substituted by one or more (eg. 1 to 4) C1-6 alkyl groups;
• such that when R1 represents —NRaRb, X does not represent a bond nor —(CRcRd)—;
• Ra, Rb, Rc, Rd, Re, Rf, Rg and Rh independently represent hydrogen or C1-6 alkyl;
• R2 represents halogen, cyano, —CF3, —CF3O, C1-6 alkyl, C1-6 alkoxy, C1-6 alkanoyl or a group —CONR5R6;
• n represents 0 to 3;
• R3 and R4 independently represent hydrogen, halogen, cyano, —CF3, —CF3O, C1-6 alkyl, C1-6 alkoxy, C1-6 alkanoyl or a group —CONR5R6;
• R5 and R6 independently represent hydrogen or C1-6 alkyl or together with the N atom to which they are attached may be fused to form a 5- to 7- membered N-containing aromatic or non-aromatic heterocyclic ring optionally interrupted by an O or S atom;
• A represents an -aryl, -heteroaryl, -aryl-aryl, -aryl-heteroaryl, -heteroaryl-aryl or -heteroaryl-heteroaryl group;
• wherein said aryl and heteroaryl groups of A may be optionally substituted by one or more (eg. 1, 2 or 3) substituents which may be the same or different, and which are selected from the group consisting of halogen, hydroxy, cyano, nitro, trifluoromethyl, trifluoromethoxy, C1-6 alkyl, trifluoromethanesulfonyloxy, pentafluoroethyl, C1-6 alkoxy, arylC1-6 alkoxy, C1-6 alkylthio, C1-6 alkoxyC1-6 alkyl, C3-7 cycloalkylC1-6 alkoxy, C1-6 alkanoyl, C1-6 alkoxycarbonyl, C1-6 alkylsulfonyl, C1-6 alkylsulfinyl, C1-6 alkylsulfonyloxy, C1-6 alkylsulfonylC1-6 alkyl, arylsulfonyl, arylsulfonyloxy, arylsulfonylC1-6 alkyl, C1-6 alkylsulfonamido, C1-6 alkylamido, C1-6 alkylsulfonamidoC1-6 alkyl, C1-6 alkylamidoC1-6 alkyl, arylsulfonamido, arylcarboxamido, arylsulfonamidoC1-6 alkyl, arylcarboxamidoC1-6 alkyl, aroyl, aroylC1-6 alkyl, arylC1-6 alkanoyl, or a group CONR7R8 or SO2NR7R8, wherein R7 and R8 independently represent hydrogen or C1-6 alkyl or R7 and R8 together with the nitrogen atom to which they are attached may form a nitrogen containing heterocyclyl or heteroaryl group.