Koch acid

1-Aminonaphthalene-3,6,8-trisulfonic acid [117-42-0]. (8-aminonaphthalene-1,3,6- trisulfonic acid), Koch acid, T acid, C10H9NO9S3, Mr 383.36, and its alkali-metal salts are readily soluble in water. The solutions are unusual for this class of compound in that they exhibit no fluorescence. Hydrolysis with dilute sulfuric acid produces 1-hydroxynaphthalene-3,6,8-trisulfonic acid, whereas diazotization followed by acid hydrolysis results in formation of the corresponding sultone. Reduction with zinc and alkali desulfonates 1-Aminonaphthalene-3,6,8-trisulfonic acid to give 1-amino-naphthalene-3,6-disulfonic acid. Amination gives 1,3-diaminonaphthalene-6,8- disulfonic acid.