One-pot synthesis of new biologically active 4-(1H-benzimidazol-2-yl)benzene-l,3-diols has been developed. The compounds were prepared by the reaction of aryl-modified sulfinylbis[(2,4-dihydroxyphenyl)methanethione]s with benzene-l,2-diamines. Their structures were identified using elemental, IR, (1)H-NMR, and mass spectra analyses. The developed method offers short reaction times, relatively large-scale synthesis, easy and quick isolation of the products, and good yields. The cytotoxicity in vitro against the 4 human cancer cell lines: SW707 (rectal), HCV29T (bladder), A549 (lung), and T47D (breast) was determined. The antiproliferative properties of some compounds studies were stronger than those of cisplatin, which was used as a comparator drug.