Recent advances on the synthesis of pyrido[3,4-c]coumarin derivatives as the backbone of natural product schumanniophytin scaffolds

Schumanniophytin is a natural pyrido[3,4-c]coumarin derivative. It was isolated from the root bark of Schumanniophyton magnificum. This compound displays central and autonomic system depressant properties and may possess potential antiviral activity. As both coumarin and pyridine are found in diverse natural process, coumarin fused pyridines have attracted significant attention in the field of synthetic as well as medicinal chemistry owing to their versatile applications. In the literature, various types of coumarins have been reported depending on how the pyridine ring fused to coumarin motif. This review highlights previously published reports on the synthetic strategies for the synthesis of specifically pyrido[3,4-c]coumarin derivatives covering the literature from 2008 to 2023. In most cases the key precursors mentioned in the literature are 3-cyano/formyl/carbonylcoumarins, which play a crucial role in the development of such derivatives.