1,3,6-Naphthalenetrisulfonic acid, 8-amino- 1-Aminonaphthalene-3,6,8-trisulfonic acid 1-Naphthylamine, 3,6,8-trisulfo- 117-42-0 8-Amino-1,3,6-naphthalenetrisulfonic acid Koch acid Koch's acid NSC227195