Synthesis of novel benzimidazole-based retrochalcones and their anticancer activity against breast and colon cancer

A series of novel 3-benzimidazolyl retrochalcones (6a–g) was synthesized and evaluated for their anticancer activities against breast (MDA-MB-231, MCF-7) and human colon (Caco-2, HCT-116) cancer cell lines. The compounds demonstrated significant anticancer potential, with compound 6d exhibiting the most potent activity (IC₅₀ < 1.56 μM) across all tested cell lines. Most compounds were more active than Roscovitine but less potent than Paclitaxel (Taxol^®). Notably, compound 6e was inactive against both Caco-2 and MDA-MB-231 cell lines. The presence of electron-donating methoxy groups enhanced anticancer efficacy, while electron-withdrawing nitro groups had a detrimental effect. The high amplitude values (70%–98%) observed for the compounds indicate effective targeting of cancer cells, while lower amplitudes in fibroblasts (27%–49%) suggest selective antimitotic effects. These findings highlight the potential of benzimidazole-supported retrochalcones as promising candidates for further development as broad anticancer agents.