Squarylium cyanine dyes are compounds 1,3-disubstituted that have a central four-carbon ring, derived from squaric acid, attached to aromatic or heterocyclic rings. These compounds have a zwiteronic structure, that typically absorbs in the visible to near-infrared region and, normally, present high molar absorption coefficient, high photochemical stability, and good photoconductivity. Considering these properties and depending on the potential application of this class of compounds, changes in their structure can be made.
In this work, two squarylium cyanine dyes were synthesized and characterized by the usual analytical techniques, including by UV-Vis-NIR absorption and emission spectroscopy. Their antifungal activity was evaluated, through the obtention of MIC values, using yeasts of the species Saccharomyces cerevisiae as a biological model and the results will be presented.