Synonyms: 4-[(2,4-Dihydroxyphenyl)azo]-5-hydroxy-2,7-naphthalenedisulfonic acid;Einecs 222-843-5;spectrophotometricreagentforthedeterminationofbbyfia;H-Resorcinol [Spectrophotometric reagent for the determination of B by FIA];H-RESORCINOL [SPECTROPHOTOMETRIC REAGENT FOR THE DETERMINATION OF B BY FIA.];H-RESORCINOL;4-[(2,4-dihydroxyphenyl)azo]-5-hydroxynaphthalene-2,7-disulphonic acid;4-(2,4-Dihydroxyphenylazo)-5-hydroxynaphthalene-2,7-disulfonic acid;H-resorcinol;1-(2,4-Dihydroxy-1-phenylazo)-8-hydroxynaphthalene-3,6-disulfonic acid disodium salt;1-(2,4-DIHYDROXY-1-PHENYLAZO)-8-HYDROXYNAPHTHALENE-3,6-DISULFONIC ACID DISODIUM SALT;