Tricyclic fused pyrimidine derivatives, their production and use

Abstract From the Canadian patent

Novel tricyclic fused pyrimidine derivatives of the formula (I):, (see formula I), wherein either one of R1 and R2 is hydrogen or an optionally substituted aralkyl group and the other is hydrogen, an optionally substituted aralkyl group or an aliphatic hydrocarbon group; R3 is hydrogen an, aliphatic hydrocarbon group or acyl group; and A is an optionally substituted divalent hydrocarbon chain having 2 to 4 carbon atoms and salts thereof are strong adenosine antagonists and activate cerebral functions and metabolisms, thus being useful as therapeutic or prophylactic agents for neurological or psychic changes caused by cerebral apoplexy, brain injury or cerebral atrophy.