Synthesis, cytotoxic and antioxidant activities of new n-substituted 3-(benzimidazol-2-yl)-chromones containing 2,6-di-tert-butylphenol fragment

The reaction of 3-formylchromones and 4-((2-aminophenyl)imino)-2,6-di‑tert-butylcyclohexa-2,5-dienone gave a series of N-substituted benzimidazole derivatives, characterized by 1H and 13C NMR spectroscopy, mass spectrometry and elemental analysis. The molecular structures of compounds 1 and 4 were determined by single crystal X-ray diffraction studies. Compounds 1–8 exhibit cytotoxic activity against human colon cancer cells HCT116 and breast cancer cells MCF7 at submicromolar concentrations. Compound 6 is more active against tumor cells than non-malignant fibroblasts. Compounds 1, 3, 5 and 7 exhibit antioxidant activity comparable to the reference drug Trolox.