Pyrazolo[3,4-b]pyridines are a group of heterocyclic compounds presenting two possible tautomeric forms: the 1H- and 2H-isomers. More than 300,000 1H-pyrazolo[3,4-b]pyridines have been described which are included in more than 5500 references (2400 patents) up to date. This review will cover the analysis of the diversity of the substituents present at positions N1, C3, C4, C5, and C6, the synthetic methods used for their synthesis, starting from both a preformed pyrazole or pyridine, and the biomedical applications of such compounds.

中文翻译：

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1H-吡唑并[3,4-b]吡啶：合成和生物医学应用

吡唑并[3,4- b ]吡啶是一组杂环化合物，具有两种可能的互变异构形式：1 H - 和 2 H - 异构体。超过 300,000 种 1 H-吡唑并[3,4- b ] 吡啶已被描述，它们包含在最新的 5500 多份参考文献（2400 项专利）中。这篇综述将涵盖对 N1、C3、C4、C5 和 C6 位置上取代基的多样性的分析，用于合成它们的合成方法，从预先形成的吡唑或吡啶开始，以及这些化合物的生物医学应用.