A compound of formula (I) for use in the treatment or prevention of a pathological condition or disease liable to be relieved by inhibition of dihydroorotate dehydrogenase in which: R2 R4 R 1 is selected from the group consisting of hydrogen atoms, halogen atoms, C1-4 alkyl, C3-4 cycloalkyl, -CF3 and -OCF3, R2 is selected from the group consisting of hydrogen atoms, halogen atoms and C1-4 alkyl group, R3 is selected from the group consisting of -COOR 5 groups , -CONHR 5, tetrazolyl, -SO2NHR 5 and -CONHSO2R 5, where R 5 is selected from the group consisting of a hydrogen atom and linear or branched C1-4 alkyl groups, R 4 is selected from the group consisting of a hydrogen atom and a C1-4 alkyl group, R 9 is selected from the group consisting of a hydrogen atom and a phenyl group, G 1 represents a group selected from N and CR 6, where R 6 is selected from the group consisting of hydrogen atoms, halogen atoms, C1-4 alkyl groups, C3-4 cycloalkyl, C1-4 alkoxy, -CF3, -OCF3, C5-7 heteroaryl containing monocyclic N, C3-7 heterocyclyl containing monocyclic N and a C6-10 aryl group which is optionally substituted With one or more substituents selected from halogen atoms and a C1-4 alkyl group, G 2 represents a group selected from: - a hydrogen atom, a hydroxy group, a halogen atom, a C3-4 cycloalkyl group, a group C1-4 alkoxy and -NR a R b, where R a represents a C1-4 alkyl group and R b is selected from a group consisting of C1-4 alkyl group and C1-4 alkoxy group-C1-4 alkyl, or R a and R b together with the nitrogen atom to which they are attached form a saturated 6 to 8 membered heterocyclic ring that optionally contains an oxygen atom as an additional heteroatom, - a monocyclic or bicyclic 5 to 10 membered heteroaromatic ring containing one or more nitrogen atoms that is optionally substituted with one or more substituents selected from halogen atoms, C1-4 alkyl, C1-4 alkoxy, C3-4 cycloalkyl, C3-4 cycloalkoxy, -CF3 and -CONR 7 R 8, where R 7 and R 8 are independently selec
