There are described Compounds of formula (I) in which R3 to R8 are independently selected from hydrogen, halogen, trihaloalkyl, alkyl having 1, 2, 3, 4 or 5 carbon atoms, electron donor groups selected from alkoxy having 1, 2, 3, 4 or 5 carbon atoms, trihaloalkoxy, hydroxy or amino, electron acceptor groups selected from cyano, sulphonic, nitro, or amide； R1 is an optionally substituted phenyl, benzyl or cyclohexyl group； R2 is selected from amino, substituted amino or guanidino groups, Z is a saturated or unsaturated C1-5 hydrocarbon chain, and salts thereof. A process for their preparation and compositions containing them are also described. The Compounds are either agonists or antagonists of a specific adenosine receptor or a number of adenosine receptors and have usefulness for the treatment of inflammation, arthritic conditions, rheumatoid arthritis, osteoarthritis, mental disorders, or for inducing central nerve regeneration.
