Synonyms: 4H-Pyrazolo[3,4-d]pyrimidine-4,6(5H)-dione,1,7-dihydro- (6CI);1H,3H,9H-Alloxanthine;1H-Pyrazolo[3,4-d]pyrimidin-4,6-diol;4,6-Dihydroxypyrazolo[3,4-d]pyrimidine;4,6-Dioxopyrazolo[3,4-d]pyrimidine;Alloxanthine;BW 55-5;NSC 76239;Oxipurinol;Oxoallopurinol;Oxyprim;Oxypurinol;