The molecule is an organosulfonate oxoanion obtained by the removal of three protons from Fast green FCF(1+). It is a conjugate base of a Fast green FCF(1+).
2-[[4-[ethyl-[(3-sulfonatophenyl)methyl]amino]phenyl]-[4-[ethyl-[(3-sulfonatophenyl)methyl]azaniumylidene]cyclohexa-2,5-dien-1-ylidene]methyl]-5-hydroxybenzenesulfonate