New asymmetrical mono-(tri)-methine and azomethine cyanine dyes of pyrazolo[5,4-b] quinolino [a, b]-1,4-pyra-(oxa)-zinium bromide salts were prepared. The new synthesized cyanines were identified by elemental and spectral analyses. The visible absorption spectra of some selected dyes were investigated in single and mixed solvents, and also in aqueous buffer solutions. The spectral shifts were studied in relation to molecular structure and in terms of medium effects. Molecular complex formation with DMF was verified through mixed-solvent studies.
