Triazol[4,5-d] pyramidine derivatives and their use as purinergic receptor antagonists

The use of a compound of formula (I): wherein R 1 is selected from H, alkyl, aryl, alkoxy, aryloxy, alkylthio, arylthio, halogen, CN, NR 5 R 6 , NR 4 COR 5 , NR 4 CONR 5 R 6 , NR 4 CO 2 R 7 and NR 4 SO 2 R 7 ; R 2 is selected from aryl attached via an unsaturated carbon; R 3 is selected from H, alkyl, COR 5 , CO 2 R 7 , CONR 5 R 6 , CONR 4 NR 5 R 6 and SO 2 R 7 ; R 4 , R 5 and R 6 are independently selected from H, alkyl and aryl or where R 5 and R 6 are in an NR 5 R 6 group, R 5 and R 6 may be linked to form a heterocyclic group, or where R 4 , R 5 and R 6 are in a (CONR 4 NR 5 R 6 ) group, R 4 and R 5 may be linked to form a heterocyclic group; and R 7 is selected from alkyl and aryl, or a pharmaceutically acceptable salt thereof or prodrug thereof, in the treatment or prevention of a disorder in which the blocking of purine receptors, particularly adenosine receptors and more particularly A 2A receptors, may be beneficial, particularly wherein said disorder is a movement disorder such as Parkinson's disease or said disorder is depression, cognitive or memory impairment, acute or chronic pain, ADHD or narcolepsy, or for neuroprotection in a subject; compounds of formula (I) for use in therapy; and novel compounds of formula (I) per se.