1 1XM 4-amino-1,7-dihydro-6h-pyrazolo[3,4-D]pyrimidine-6-thione 1.000 2 TVW 1h-pyrazolo[3,4-D]pyrimidin-4-amine 0.909 3 A1I5U 6-sulfanylidene-1,7-dihydropyrazolo[3,4-D]pyrimidin-4-one 0.833 4 A1I5V 3-methyl-1~{H}-pyrazolo[3,4-D]pyrimidin-4-amine 0.833 5 A1BD4 Allopurinol 0.750