Ring architecture not only influences molecular properties, spatial arrangement, and scaffold rigidity but also determines molecular function and regulation. Compared with the traditional construction of ring frameworks that often requires starting from scratch, the development of methods for directly editing the ring skeleton lags far behind, which is largely attributed to the inertness of chemical bonds that constitute the frameworks. This review focuses on recent progress (post 2021) in the development of ring-expanding single-atom skeletal editing via ring expansion or carbon-atom insertion, enabling a more efficient and accurate synthetic strategy for the synthesis of important scaffolds in drug discovery and beyond, as well as its application in late-stage molecular transformations and streamlined synthesis of bioactive molecules.

中文翻译：

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碳原子加成在扩环单原子骨架编辑中的最新进展


环结构不仅影响分子特性、空间排列和支架刚度，还决定分子功能和调节。与通常需要从头开始的传统环框架构建相比，直接编辑环骨架的方法的发展远远落后，这在很大程度上归因于构成框架的化学键的惰性。本文重点介绍了通过扩环或碳原子插入开发扩环单原子骨架编辑的最新进展（2021 年后），为药物发现及其他领域中重要支架的合成提供了更高效、更准确的合成策略，以及其在后期分子转化和生物活性分子的简化合成中的应用。