This work describes the synthesis and characterization of a heterogeneous catalyst consisting of piperazine-functionalized reduced graphene oxide decorated with Fe3O4 nanoparticles ( Fe3O4@rGO-NH), and the study of its catalytic activity as a magnetic heterogeneous catalyst for the Pechmann synthesis of coumarins. Catalyst Fe3O4@ rGO-NH was fully characterized by various techniques, including IR, XRD, TEM, VSM, TGA, and elemental analysis. Then, the catalyst was used as an efficient and easy-separable heterogeneous catalyst for the solvent-free synthesis of some coumarins by Pechmann reaction. The reaction was optimized in terms of reaction time and temperature, catalyst dosage, and the presence/absence of the solvent. Finally, the reusability of the catalyst was studied.

Some known coumarins, decursin, nodakenetin, umbelliferone, 7-demethylsuberosin, columbianetin, decursinol angelate and decursinol, showing significant cytotoxic activities against P388 cell lines,were isolated from the roots of Angelica gigas (Umbelliferae) . 7-Demethylsuberosin and columbianetinwere obtained from Angelica gigas for the first time. Chernotaxonornic difference about coumarins com-ponents between the roots of Angelica gigas and those of A. acutiloba is also discussed.