Coumarins (benzopyran-2-ones) and benzofurans belong to an important class of natural compounds and have long attracted significant scientific attention due to their diverse biological properties and high synthetic potential for structural modification. Introducing functional groups and pharmacophoric substituents into the structure of coumarins with a benzofuran fragment is a relevant and practically oriented task. The aim of the presented study was to explore the possibilities of structural modification of 3-(5-hydroxybenzofuran-3-carbonyl)-2H-chromen-2-one and to introduce additional functional groups into its structure, such as amino groups, hydroxyl groups, amidoxime fragments, and oxadiazole rings – key moieties for the creation of new pharmaceuticals, agrochemicals, and functional materials. The objects of study include alkylation, amidation, heterocyclization, and epoxide ring-opening as approaches to create structurally diverse derivatives based on 3-(5-hydroxybenzofuran-3-carbonyl)coumarin, along with the spectral characteristics of the synthesized compounds