Iron-Catalyzed PhotoinducedDecarboxylative CascadeProcess for the Synthesis of Functionalized Pyrazolones and Evaluationof Biological Activity

Abstract In this work, we established a decarboxylative cascade process to achieve functionalized pyrazolones. This approach directly employs carboxylic acids as alkylating reagents. An inexpensive iron photocatalyst enables this process when irradiated by visible light. The reaction demonstrated a broad substrate scope, proving compatible with various carboxylic acids and N-acrylohydrazones. Furthermore, biological activity evaluation revealed that compound 3ak acted as a potent inhibitor of NO production, while compound 3al exhibited potent antiproliferative activity against the PANC-1 cell line, with an IC50 value of 14.3 μM.