Synonyms: 2H-Naphtho(1,2-d)triazole-5-sulfonic acid, 2-(4-(2-(4-nitro-2-sulfophenyl)ethenyl)-3-sulfophenyl)-, sodium salt (1:3);2H-Naphtho(1,2-d)triazole-5-sulfonic acid, 2-(4-(2-(4-nitro-2-sulfophenyl)ethenyl)-3-sulfophenyl)-, trisodium salt;Trisodium 2-(4-(2-(4-nitro-2-sulphonatophenyl)vinyl)-3-sulphonatophenyl)-2-H-naphtho(1,2-d)triazole-5-sulphonate;trisodium 2-{4-[(E)-2-(4-nitro-2-sulfonatophenyl)ethenyl]-3-sulfonatophenyl}-2H-naphtho[1,2-d][1,2,3]triazole-5-sulfonate