6-Amino-5-cyano-3-methyl-1,4-diarylpyrano[2,3-c]pyrazole derivatives were prepared via the interaction ofα, β-unsaturated nitriles with 3-methyl-1-phenylpyrazol-5-one as starting materials in the synthesis of new asymmetrical mono-(tri)-methine cyanine dyes. The new cyanines were characterised by elemental analysis, IR and1H-NMR spectral data. The visible absorption spectra of some selected dyes were investigated in pure and mixed solvents as well as in aqueous buffer solutions.
