Synthesis of Costunolide Derivatives by Pd-catalyzed Heck Arylation and Evaluation of Their Cytotoxic Activities

As part of pharmacological–phytochemical integrated studies of medicinal plants from Indian flora, costunolide (1) was isolated as a major compound from Saussurea lappa, plant traditionally used in different Asian traditional medicine systems. To improve the efficacy of this natural product lead, a series of analogues have been synthesized by the coupling of various aryl iodides using the standard Heck reaction conditions and evaluated for their cytotoxic activities against human cancer cell lines. The results indicated that several of the analogues were effective against the tested cell lines compared to the parent compound costunolide. Among the tested compounds, 2c and 2j demonstrated good activity against Hela cell line while compounds 2d showed potent activity against DU-145 and MCF-7 cell lines, respectively.