Synthesis and antitumor activity of novel cyclopropapyrroloindole (CPI) derivatives bearing bis(methoxycarbonyl) groups

The title synthesis was achieved by employing oxidative cyclization of the enaminodiester prepared by Michael addition of the 5-aminoindoline with dimethyl acetylenedicarboxylate, as a key step. Some of these novel bis(methoxycarbonyl)cyclopropapyrroloindole (MC2CPI) derivatives 9c, d and their seco-chlorides 18c, d were found to exhibit prominent cytotoxicity and antitumor activity against P388 murine leukemia.