Synthesis and Biological Evaluation of 3-Chloro-4-(indol-3-yl)-2,5- pyrroledione Derivatives as Antitumor Agents

A series of 3-chloro-4-(indol-3-yl)-2,5-pyrroledione derivatives were synthesized and evaluated for their cytotoxic activities in vitro against five human cancer cell lines (K562, A549, ECA-109, KB and SMMC-7721). Most compounds displayed potent cytotoxicity with IC50 values in low micromolar range. The results showed that the existence of the chlorine atom at 3-position on the pyrroledione ring was crucial for the activity. Compound 6a, the most potent one (IC50: 0.67∼3.93 μM), would be a promising template for further development of novel antitumor agents