Green synthesis of Fe3O4/ZnO magnetic core‐shell nanoparticles by Petasites hybridus rhizome water extract and their application for the synthesis of pyran derivatives: Investigation of antioxidant and antimicrobial activity

In this research, Fe3O4/ZnO magnetic core‐shell nanoparticles (Fe3O4/ZnO MCNPs) were synthesized through a green method using Petasites hybridus rhizome water extract as a reducing and stabilizing agent. The morphology and size of the Fe3O4/ZnO MCNPs was identified by X‐ray diffraction, scanning electron microscopy, and Energy‐dispersive X‐ray spectroscopy (EDX) analysis. The catalytic activity of the Fe3O4/ZnO MCNPs was evaluated in the efficient and green preparation of pyran derivatives in excellent yield using three‐component reactions of dimedone, aldehydes, and malononitrile in ethanol at room temperature. The ability of some synthesized compounds to scavenge the 2,2‐diphenyl‐1‐picrylhydrazyl radical was measured and the results proved this observation. Moreover, the antimicrobial activity of some synthesized compounds was proved by employing the disk diffusion test on Gram‐positive and Gram‐negative bacteria. The results for the disk diffusion test showed that compounds (4c, 4d, 4f and 4g) prevented bacterial growth. In this research, the Fe3O4/ZnO MCNPs were synthesized through a green method using Petasites hybridus rhizome water extract as a reducing and stabilizing agent. The catalytic activity of the Fe3O4/ZnO MCNPs was evaluated in the efficient and green preparation of pyran derivatives in excellent yield. The ability of some synthesized compounds to scavenge the DPPH radical was measured and the results proved this observation. Moreover, the antimicrobial activity of some synthesized compounds proved by employing the disk diffusion test on Gram‐positive and Gram‐negative bacteria.