摘要 |
Novel pyrazolo[3,4-d]pyrimidine derivatives represented by the general formula (I) <IMAGE> wherein R1 is an aryl or heteroaryl group which may be substituted by one to three members selected from the class consisting of halogen, C1-4alkyl, C1-4alkoxy, nitro, amino, N-C1-4alkylamino, N,N-diC1-4alkylamino, hydroxy, trifluoromethyl, carbamoyl, N-C1-4alkylcarbamoyl and N,N-diC1-4alkylcarbamoyl; R2 is C1-4 alkyl; R3 and R4 are independently hydrogen or C1-4 alkyl; R5 is hydrogen, C1-2alkyl, C1-5alkanoyl or C1-4alkoxycarbonyl, the group R5 being attached at the 1- or 2-position of the pyrazole ring; X is C1-7alkylene or a group of the formula: -(CH2)m-Y-(CH2)n- wherein m is 2 or 3, n is an integer of 0 to 3, and Y is oxygen, sulfur, imino or N-C1-4alkylimino; and the dotted line designates the presence of two double bonds in the pyrazole ring and their salts activate cerebral functions and metabolisms. |