Synthesis of novel benzofuran-4,7-quinones from 4,6-dimethoxybenzofurans specifically targeting breast and lung cancer cells

4,6-Dimethoxy-2-phenylbenzofurans were synthesized from the one-pot reactions of 3,5-dimethoxyphenol and a range of alpha-bromoacetophenones. The dimethoxybenzofurans were then selectively formylated at C7 using Vilsmeier-Haack method to generate 4,6-dimethoxybenzofuran-7-carbaldehydes which have been effectively converted to 6-dimethoxybenzofuran-4,7-quinones by Dakin oxidation. The cytotoxic potentials of the targeted compounds in MDA-MB-231 breast cancer and A549 lung cancer cell lines were investigated and compared to the cytotoxicity profiles of normal breast and bronchial cells. 2-Phenylbenzofurans mostly targeted lung cancer cells whereas benzofuran-7-carbaldehydes were specifically cytotoxic for metastatic breast cancer cells. The targeted benzofuran derivatives were found to be the most effective compounds for lung and breast cancer. ADME analyses showed lethal doses of all compounds excluding benzofuran-4,7-quinones are around 4000 mg/kg.