2,5-Diaminobenzene sulfonic acid 2,5-Diaminobenzenesulfonic acid 2,5-Diaminobenzenesulphonic acid 2-Sulfo-p-phenylenediamine 4-14-00-02771 (Beilstein Handbook Reference) 77847-12-2 88-45-9 BRN 2970398 Benzenesulfonic acid, 2,5-diamino- CCRIS 2884 EINECS 201-832-9 p-Phenylenediaminesulfonic acid