Pyrazolo[4,3-d]pyrimidine, a fused heterocycle bearing pyrazole and pyrimidine portions has gained a significant attention in the field of bioorganic and medicinal chemistry. Pyrazolo[4,3-d]pyrimidine derivatives have demonstrated numerous pharmacological activities particularly, anti-cancer, anti-infectious, phosphodiesterase inhibitors, adenosine antagonists and cytokinin antagonists etc. This review extensively unveils the synthetic and pharmacological diversity with special emphasis on structural variations around pyrazolo[4,3-d]pyrimidine scaffold. This endeavour has thus uncovered the medicinal worthiness of pyrazolo[4,3-d]pyrimidine framework. To the best of our knowledge this review is the first compilation on synthetic, medicinal and structure activity relationship (SAR) aspects of pyrazolo[4,3-d]pyrimidines since 1956.

吡唑并[4，3- d ]嘧啶是带有吡唑和嘧啶部分的稠合杂环，在生物有机和药物化学领域引起了广泛关注。吡唑并[4,3- d ]嘧啶衍生物已显示出许多药理活性，特别是抗癌，抗感染，磷酸二酯酶抑制剂，腺苷拮抗剂和细胞分裂素拮抗剂等。该综述广泛揭示了合成和药理学多样性，特别着重于结构变异围绕吡唑并[4,3- d ]嘧啶骨架。因此，这项努力发现了吡唑并[4,3- d]嘧啶骨架。据我们所知，本综述是自1956年以来关于吡唑并[4,3- d ]嘧啶的合成，药物和结构活性关系（SAR）方面的第一本汇编。