Compounds of following general formula (Ia): in which X is N characterized in that - the phenyl group is substituted by n Y-B group(s), n varying from 1 to 5, said Y-B group being such that: - Y represents a linear or branched, saturated or unsaturated alkylene group, comprising from 1 to 6 carbon atoms, preferably from 2 to 4 carbon atoms, and - B represents a group chosen from: - an aryl or heteroaryl group, in particular a phenyl or naphthyl group - a C 5 -C 10 heterocyclic group, preferentially in C 5 -C 6, comprising 1 to 6 heteroatoms chosen from the elements of the chalcogen and pnictogen families, and - a C 3 -C 6 cycloalkyl group, said B group being substituted by one or more substituent(s), preferentially by one substituent, said substituent(s) being chosen from the group comprising: ∘ a halogen atom, ∘ an alkoxy group comprising from 1 to 4 carbon atoms, ∘ an aryloxy group, in particular a phenyloxy group ∘ a saturated or unsaturated, linear, branched or cyclic alkyl group, comprising from 1 to 6 carbon atoms, preferably from 2 to 4 carbon atoms, optionally substituted by one or more halogen atoms, and ∘ an aryl group, preferentially a phenyl group, optionally substituted by a C 1 -C 4 alkyl, ∘ a hydroxyl group, ∘ a thiol group, ∘ an amine group, ∘ an amide group, ∘ a carboxylic acid group, ∘ a cyano group, ∘ an azide group, and ∘ a nitro group, said compounds being in the form of a racemate, of any one of their enantiomers, or any one of the different tautomers corresponding to said racemates and enantiomers, as well as in the form of their pharmaceutically acceptable salts. - the phenyl group is substituted by n Y-B group(s), n varying from 1 to 5, said Y-B group being such that: - Y represents a linear or branched, saturated or unsaturated alkylene group, comprising from 1 to 6 carbon atoms, preferably from 2 to 4 carbon atoms, and - B represents a group chosen from: - an aryl or heteroaryl group, in particular a phenyl or naphthyl group - a C 5 -C 10 heterocyclic group, preferentially in C 5 -C 6, comprising 1 to 6 heteroatoms chosen from the elements of the chalcogen and pnictogen families, and - a C 3 -C 6 cycloalkyl group, said B group being substituted by one or more substituent(s), preferentially by one substituent, said substituent(s) being chosen from the group comprising: ∘ a halogen atom, ∘ an alkoxy group comprising from 1 to 4 carbon atoms, ∘ an aryloxy group, in particular a phenyloxy group ∘ a saturated or unsaturated, linear, branched or cyclic alkyl group, comprising from 1 to 6 carbon atoms, preferably from 2 to 4 carbon atoms, optionally substituted by one or more halogen atoms, and ∘ an aryl group, preferentially a phenyl group, optionally substituted by a C 1 -C 4 alkyl, ∘ a hydroxyl group, ∘ a thiol group, ∘ an amine group, ∘ an amide group, ∘ a carboxylic acid group, ∘ a cyano group, ∘ an azide group, and ∘ a nitro group, - Y represents a linear or branched, saturated or unsaturated alkylene group, comprising from 1 to 6 carbon atoms, preferably from 2 to 4 carbon atoms, and - B represents a group chosen from: - an aryl or heteroaryl group, in particular a phenyl or naphthyl group - a C 5 -C 10 heterocyclic group, preferentially in C 5 -C 6, comprising 1 to 6 heteroatoms chosen from the elements of the chalcogen and pnictogen families, and - a C 3 -C 6 cycloalkyl group, - an aryl or heteroaryl group, in particular a phenyl or naphthyl group - a C 5 -C 10 heterocyclic group, preferentially in C 5 -C 6, comprising 1 to 6 heteroatoms chosen from the elements of the chalcogen and pnictogen families, and - a C 3 -C 6 cycloalkyl group, ∘ a halogen atom, ∘ an alkoxy group comprising from 1 to 4 carbon atoms, ∘ an aryloxy group, in particular a phenyloxy group ∘ a saturated or unsaturated, linear, branched or cyclic alkyl group, comprising from 1 to 6 carbon atoms, preferably from 2 to 4 carbon atoms, optionally substituted by one or more halogen atoms, and ∘ an aryl group, preferentially a phenyl group, optionally substituted by a C 1 -C 4 alkyl, ∘ a hydroxyl group, ∘ a thiol group, ∘ an amine group, ∘ an amide group, ∘ a carboxylic acid group, ∘ a cyano group, ∘ an azide group, and ∘ a nitro group,