Synthesis and solvatochromism of dipodal and tripodal dyes derived from Brooker’s merocyanine

•Four push–pull dyes derived from Brooker’s merocyanine synthesized and characterized.•The dyes have a phenolate moiety connected to two or three N–methylpyridinium groups.•Negative solvatochromism, showing very different colors, in the solvents studied.•The longest wavelength absorption bands in the dyes are due to a π → π* transition.•The acidity is the most important contribution for the solvation of the probes.