Orientation in the synthesis and absorption spectra of 1H-pyrazolo[4,3-d][1,3]oxazole methine cyanine dyes

3,5Dimethyl-1-phenyl-1H-pyrazolo[4,3-d][1,3]oxazole was prepared and orient ed as starting material in the synthesis of some mono-, di-, and trimethine cyanine dyes. The new cyanines were characterized, by IR and H-1 NMR spect ral data. The visible absorption spectra of the cyanine dyes are discussed.