Analogues and derivatives of nucleic acid components have been used as key drugs in different areas of medicine over the past decades. The replacement of one or more nitrogen atoms of the heterocyclic base with a CH group affords deazapurine nucleoside analogues, and the replacement of the methine group with a nitrogen atom gives azapurine derivatives. A combination of aza and deaza moieties in the purine base leads to aza(deaza)-modified bases. Some nucleoside analogues were found to exhibit pronounced anticancer and antiviral activity. The synthesis and evaluation of biological activity of aza- and deazapurine nucleoside analogues have attracted interest from researchers four decades ago. This review describes and integrates the studies concerning certain aspects of the synthesis and(or) activity of various representatives of this class of compounds. The structure–biological activity relationships are analyzed. The successful approaches to the design of aza- and deazapurine nucleoside analogues are considered. A comparison is given for the methods of chemical and enzymatic synthesis of these compounds.The bibliography includes 161 references.

中文翻译：

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嘌呤核苷氮杂和脱氮杂类似物的合成及生物活性

在过去的几十年中，核酸成分的类似物和衍生物已被用作不同医学领域的关键药物。杂环碱基的一个或多个氮原子被 CH 基团取代得到脱氮杂嘌呤核苷类似物，而次甲基被氮原子取代得到氮杂嘌呤衍生物。嘌呤碱基中氮杂和脱氮杂部分的组合产生氮杂（脱氮杂）修饰的碱基。发现一些核苷类似物表现出显着的抗癌和抗病毒活性。40 年前，氮杂和脱氮嘌呤核苷类似物的生物活性的合成和评价已经引起了研究人员的兴趣。这篇综述描述并整合了关于这类化合物的各种代表的合成和（或）活性的某些方面的研究。分析了结构-生物活性关系。考虑了设计氮杂和脱氮嘌呤核苷类似物的成功方法。对这些化合物的化学合成和酶促合成方法进行了比较。参考书目包括 161 篇参考文献。