Polymethine dye derivatives of pyrazolo[4, 5-d]thiazole

Quino(2)monomethine-, carbo-, mero-, dimero-, and rhodacyanines, as well as styryl dyes containing 4-methyl-6-phenyl- and 4, 6-diphenlpyrazolo4, 5-d]thiazoles groupings are prepared. Study of the colors of the synthesized dyes, showed that dyes containing a pyrazolo4, 5-d]moiety to be considerably more deeply colored, than the corresponding benzothiazole derivatives.