The combination of heterocycles offers a new opportunity to create novel multicyclic compounds having improved biological activity. Coumarins are ubiquitous natural heterocycle widely adopted in the design of various biologically active compounds. Fusing different heterocycles with coumarin ring is one of the interesting approaches to generating novel hybrid molecules having highlighted biological activities. In the efforts to develop heterocyclic-fused coumarins, a wide range of 3,4-heterocycle-fused coumarins have been introduced bearing outstanding biological activity. The effect of heterocycles annulation at 3,4-positions of coumarin ring on the biological activity of the target structures were discussed. This review focuses on the important progress of 3,4-heterocycle-fused coumarins providing better insight for medicinal chemists on the design and preparation of biologically active heterocycle-fused coumarins with a significant therapeutic effect in the future.

杂环的组合为创造具有改善的生物活性的新型多环化合物提供了新的机会。香豆素是无处不在的天然杂环，广泛用于各种生物活性化合物的设计中。将不同的杂环与香豆素环融合是产生具有突出生物活性的新型杂合分子的有趣方法之一。在开发杂环融合的香豆素的努力中，已经引入了具有优异生物活性的各种各样的3，4-杂环融合的香豆素。讨论了香豆素环3,4-位杂环杂环化对目标结构生物学活性的影响。这项审查着重于3的重要进展，