2-styryl-benzimidazole 45 showed broad spectrum solar protection against UVA and UVB rays. The antiproliferative effect of the benzimidazoles was tested on human skin melanoma Colo-38 cells. The styrylbenzimidazole 45 exhibited antiproliferative effect at low micromolar concentration against Colo-38 cells and very low antiproliferative activity on normal HaCat keratinocyte cells.