According to the invention there is provided a compound of formula A1 which may be useful in the treatment of a condition or disorder ameliorated by the inhibition of the A1-A2b or, particularly, the A2a receptor wherein the compound of formula A1 has the structure, wherein, A represents Cy1 or HetA； Cy1 represents a 5- to 14-membered aromatic, fully saturated or partially unsaturated carbocyclic ring system comprising one, two or three rings, which Cy1 group is optionally substituted by one or more R4a substituents； HetA represents a 5- to 14-membered heterocyclic group that may be aromatic, fully saturated or partially unsaturated, and which contains one or more heteroatoms selected from O, S and N, which heterocyclic group may comprise one, two or three rings and which HetA group is optionally substituted by one or more R4b substituents； B represents a Cy2 or HetB； Cy2 represents a 3- to 10-membered aromatic, fully saturated or partially unsaturated carbocyclic ring system comprising one or two rings, which Cy2 group is optionally substituted by one or more R4c substituents； HetB represents a 3- to 10-membered heterocyclic group that may be aromatic, fully saturated or partially unsaturated, and which contains one or more heteroatoms selected from O, S and N, which heterocyclic group may comprise one or two rings and which HetB group is optionally substituted by one or more R4d substituents.L'invention concerne un composé de formule A1 qui peut être utile pour le traitement d'un état ou trouble amélioré par l'inhibition d'A1-A2b ou, particulièrement, du récepteur A2a. Selon l'invention, le composé de formule A1 a la structure dans laquelle A représente Cy1 ou HetA ； Cy1 représente un système cyclique carbocyclique aromatique, complètement saturé ou partiellement insaturé de 5 à 14 éléments comprenant un, deux ou trois cycles, ledit groupe Cy1 étant éventuellement substitué par un ou plusieurs substituants R4a ； HetA représente un groupe hétérocyclique de 5 à 14 é
