Synthesis and Anticancer Activity of Quinoline–Benzimidazole Hybrids

New quinoline–benzimidazole hybrids 3a–3d have been synthesized from 1-(quinolin-5-yl)­ethanone and benzene-1,2-diamine and converted to the corresponding N-tosyl (4a–4d) and N-methyl derivatives (5a–5d). The synthesized compounds were characterized by IR, NMR, and mass spectra. Compounds 4a and 4c demonstrated exceptional anticancer efficacy against HeLa cell line. Compounds 4a and 4d, however, were more active against HT-29 cell line.