Site-Selective Rhodium(III)-Catalyzed C−H Amination of 7-Azaindoles with Anthranils: Synthesis and Anticancer Evaluation

The site-selective C–H amination reaction of 7-azaindoles with various benzisoxazoles as amination surrogates under cationic rhodium(III) catalysis is described. This transformation efficiently provides a range of ortho-aminated N-aryl-7-azaindoles with excellent site-selectivity and functional group compatibility. The formed ortho-aminated 7-azaindoles were readily transformed into biologically relevant heterocycles such as azaindoloacridine, azaindoloacridone, and bis-indole compounds. Moreover, the synthetic derivatives were tested for in vitro anticancer activity against human breast adenocarcinoma cells (MCF-7), human renal carcinoma cells (786-O), and human prostate adenocarcinoma cells (DU145). Notably, some synthetic compounds were found to display most potent anticancer activity, compared to that of anticancer doxorubicin as a positive control.