4-氯-1H-吡唑并[3,4-D]嘧啶-6-胺

6-氯-1,5-二氢-4H-吡唑并[3,4-d]嘧啶-4-酮

羟基嘌呤

4,6-二氯-1H-吡唑并[3,4-C]嘧啶

6-Amino-1-(2-deoxy-β-D-erythro-pentofuranosyl)-1,5-dihydro-4H-pyr azolo[3,4-d]pyrimidin-4-one