hexasodium 7,7'-[(2-hydroxypropane-1,3-diyl)bis[imino(6-chloro-1,3,5-triazine-4,2-diyl)imino[2-[(aminocarbonyl)amino]-4,1-phenylene]azo]]bisnaphthalene-1,3,6-trisulphonate

7,7'-[(2-Hydroxy-1,3-propanediyl)bis[imino(6-chloro-1,3,5-triazine-4,2-diyl)imino[2-[(aminocarbonyl)amino]-4,1-phenylene]azo]]bis(1,3,6-naphthalenetrisulfonic acid trisodium) salt