Titan yellow is a

compound Compound may refer to: Architecture and built environments * Compound (enclosure), a cluster of buildings having a shared purpose, usually inside a fence or wall ** Compound (fortification), a version of the above fortified with defensive struct ...

with formula C₂₈H₁₉N₅Na₂O₆S₄. It is a

triazene Triazene is an unsaturated inorganic compound having the chemical formula N3 H3. It has one double bond and is the second-simplest member of the azene class of hydronitrogen compounds, after diimide. Triazenes are a class of organic compoun ...

dye A dye is a colored substance that chemically bonds to the substrate to which it is being applied. This distinguishes dyes from pigments which do not chemically bind to the material they color. Dye is generally applied in an aqueous solution an ...

used as a stain and fluorescent indicator in microscopy.Thiazole Yellow G
at

Sigma-Aldrich Sigma-Aldrich (formally MilliporeSigma) is an American chemical, life science, and biotechnology company that is owned by the German chemical conglomerate Merck Group. Sigma-Aldrich was created in 1975 by the merger of Sigma Chemical Company a ...

It is also used for the colorimetric indication of various compounds and is an acid-base indicator. As an acid-base indicator, it changes color from yellow to red between pH 12 and pH 13.

References

Sulfonates Organic sodium salts Benzothiazoles Fluorescent dyes {{organic-compound-stub