4-aminopyrimidine derivatives and their as as adenosine A2a receptor antagonists

A compound of formula (I):

• wherein
• R1 represents a five-membered heteroaryl ring selected from the group consisting of a pyrazole, a thiazole, and a triazole ring optionally substituted by one or two halogen atoms or by one or two methyl groups;
• R2 represents a hydrogen atom;
• R3 represents bromine or chlorine atom;
• R4 represents independently:
• a) a five-membered heteroaryl group optionally substituted by one or more halogen atoms or by one or more groups selected from the group consisting of alkyl, cycloalkyl, alkoxy, alkylthio, amino, mono- or dialkylamino
• b) a group —N(R5)(R6) in which R5 and R6 represent independently:
• a hydrogen atom;
• an alkyl or cycloalkyl group of 3 to 6 carbon atoms, linear or branched, optionally substituted by one or more halogen atoms or by one or more groups selected from the group consisting of cycloalkyl (3-8 carbon atoms), hydroxy, alkoxy, amino, mono- and dialkylamino (1-8 carbon atoms);
• or R5 and R6 form together with the nitrogen atom to that they are attached a saturated heterocyclic group of 4 to 6 members in which further heteroatom may be inserted, which is optionally substituted by one or more halogen atoms or by one or more alkyl groups (1-8 carbon atoms), hydroxy, lower alkoxy, amino, mono- or dialkylamino, or
• c) a group —OR7 or —SR7, where R7 represents independently:
• an alkyl (1-8 carbon atoms) or cycloalkyl (3-8 carbon atoms) group, linear or branched, optionally substituted by one or more halogen atoms or by one or more groups selected from the group consisting of alkyl (1-8 carbon atoms), alkoxy (1-8 carbon atoms), amino, mono- or dialkylamino (1-8 carbon atoms);
• or
• a Phenyl ring optionally substituted with one or more halogen atoms.