1,2,4-Diazo acid

2-Naphthol-1-diazo-4-sulfonic acid

2-Hydroxy-4-sulfo-1-naphthalenediazonium

4-Diazonio-3-hydroxy-1-naphthalenesulfonic acid

Naphth[1,2-d]-(1,2,3)-oxadiazole-4-sulfonic acid