A compound of formula or a pharmaceutically acceptable salt thereof: wherein: A is hydrogen, C 1-4 alkyl, C 1-3 alkoxy, C 1-2 fluoroalkyl, halogen, NR 6 R 7, Het, or phenyl wherein the phenyl is optionally substituted by one, two or three substituents independently being fluorine, chlorine, C 1-3 alkyl or methoxy; wherein Het is: i) a 6-membered heteroaromatic monocyclic ring containing one, two or three ring-nitrogen atoms, or ii) a 5-membered heteroaromatic monocyclic ring containing one, two or three ring heteroatoms independently being N, O or S, wherein no more than one of the 5-membered ring heteroatoms is O or S; and wherein Het is optionally substituted with one or two substituents independently being C 1-3 alkyl, fluorine, chlorine, OH (including a tautomer thereof), or methoxy; and wherein: R 1 is hydrogen, chlorine, fluorine, bromine, C 1 fluoroalkyl, cyano or C 1-3 alkyl; R 2 is hydrogen, fluorine, chlorine, bromine, C 1 fluoroalkyl, cyano or C 1-3 alkyl; R 3 is hydrogen, fluorine or chlorine; R 4 is hydrogen; R 5 is hydrogen, fluorine, chlorine or methyl; and R 6 and R 7 independently are hydrogen or C 1-3 alkyl; or R 6 and R 7 are taken together and are -(CH 2) 2 -O-(CH 2) 2 -, -(CH 2) 2 -O-(CH 2) 3 -, or -(CH 2)n 1 - wherein n 1 is 3, 4, 5 or 6; wherein, when A is hydrogen, C 1-4 alkyl, C 1-3 alkoxy, C 1-2 fluoroalkyl, halogen or NR 6 R 7, then R 1 is chlorine, fluorine, bromine, C 1 fluoroalkyl, cyano or C 1-3 alkyl, and at least one of R 2 and R 3 is other than hydrogen; and when A is Het or optionally substituted phenyl, then R 1 is hydrogen, chlorine, fluorine, bromine, C 1 fluoroalkyl, cyano or C 1-3 alkyl, and at least one of R 1, R 2 and R 3 is other than hydrogen; and wherein, when R 5 is fluorine, chlorine or methyl, then R 1 is chlorine, fluorine, C 1 fluoroalkyl or methyl and R 2 is hydrogen. A is hydrogen, C 1-4 alkyl, C 1-3 alkoxy, C 1-2 fluoroalkyl, halogen, NR 6 R 7, Het, or phenyl wherein the phenyl is optionally substituted by one, two or three substituents independently being fluorine, chlorine, C 1-3 alkyl or methoxy; i) a 6-membered heteroaromatic monocyclic ring containing one, two or three ring-nitrogen atoms, or ii) a 5-membered heteroaromatic monocyclic ring containing one, two or three ring heteroatoms independently being N, O or S, wherein no more than one of the 5-membered ring heteroatoms is O or S; R 1 is hydrogen, chlorine, fluorine, bromine, C 1 fluoroalkyl, cyano or C 1-3 alkyl; R 2 is hydrogen, fluorine, chlorine, bromine, C 1 fluoroalkyl, cyano or C 1-3 alkyl; R 3 is hydrogen, fluorine or chlorine; R 4 is hydrogen; R 5 is hydrogen, fluorine, chlorine or methyl; and R 6 and R 7 independently are hydrogen or C 1-3 alkyl; or R 6 and R 7 are taken together and are -(CH 2) 2 -O-(CH 2) 2 -, -(CH 2) 2 -O-(CH 2) 3 -, or -(CH 2)n 1 - wherein n 1 is 3, 4, 5 or 6; wherein, when A is hydrogen, C 1-4 alkyl, C 1-3 alkoxy, C 1-2 fluoroalkyl, halogen or NR 6 R 7, then R 1 is chlorine, fluorine, bromine, C 1 fluoroalkyl, cyano or C 1-3 alkyl, and at least one of R 2 and R 3 is other than hydrogen; and when A is Het or optionally substituted phenyl, then R 1 is hydrogen, chlorine, fluorine, bromine, C 1 fluoroalkyl, cyano or C 1-3 alkyl, and at least one of R 1, R 2 and R 3 is other than hydrogen; and wherein, when R 5 is fluorine, chlorine or methyl, then R 1 is chlorine, fluorine, C 1 fluoroalkyl or methyl and R 2 is hydrogen.