Synthesis of high molar extinction coefficient push-pull tricyanofuran-based disperse dyes: Biological activity and dyeing performance

Several push–pull tricyanofuran-based disperse dyes with high molar extinction coefficient were synthesized and fully characterized. The dyes were prepared via Knoevenagel reaction in dry pyridine under ambient conditions employing acetic acid as catalyst. The condensation process was carried out between the reactive methyl-bearing tricyanofuran moiety and tertiary amine-based arylaldehyde. The molecular structures of the synthesized chromophores were proved by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (1H and 13C NMR) and elemental analysis (C, H, N). The UV-Vis absorbance spectra of the synthesized dyes demonstrated interesting extinction coefficient values, which were found to be influenced by the aromatic-vinyl bridge and the tertiary amine donor group bonded to this aromatic-vinyl bridge moiety. The prepared tricyanofuran-based disperse colorants were dyed on polyester fabrics to afford satisfactory results. The substituents attached to the tertiary amine moiety influenced the absorption maxima. The fastness properties of the dyed polyester samples were measured. The biological activities of the synthesized dyestuffs against fungus (Candida Albican) as well as Gram-positive (S. Aureus) and Gram-negative (E. Coli) pathogens were also evaluated.