2,2'-Thiobis[5-(p-hydroxyphenylazo)benzenesulfonic acid]

2,2'-thiobis[5-[(4-hydroxyphenyl)azo]-Benzenesulfonic acid

2,2'-thiobis[5-[(4-hydroxyphenyl)azo]benzenesulphonic] acid, sodium salt

2,2'-Thiobis[5-[(4-hydroxyphenyl)azo]benzenesulfonic acid]/sodium,(1:x) salt