Regioselective Synthesis and in Vitro Anticancer Activity of 4-Aza-podophyllotoxin Derivatives Catalyzed by L-Proline

A series of 4-aza-podophyllotoxin derivatives have been synthesized regioselectively via the three-component reaction of aldehydes, aromatic amines, and tetronic acid catalyzed by L-proline. This method has the advantages of high yield, high regioselectivity, extensive adaptability, easy operation, and environmental friendliness. These compounds were also investigated in vitro, and sonic were found to have good anticancer activity.