Novel quinone cyanine dyes: synthesis and spectral studies

Novel dimethine, bis dimethine and tetramethine cyanine dyes derived from benzo [4,5-b; 4′,5′-b′] bis furo, thieno and pyrrolo-4,8-dione were prepared. The electronic visible absorption spectra of the dyes were examined in 95% ethanol. Structural confirmation is carried out by elemental analysis, IR and 1H NMR spectral data.