The molecule is a flavonoid oxoanion that is a trianionic form of 3,3'-biflaviolin. It is the major microspecies at pH 7.3 (according to Marvin v 6.2.0.). It is a conjugate base of a 3,3'-biflaviolin 2,2'-diolate.
2-(6,8-dihydroxy-1-oxido-3,4-dioxonaphthalen-2-yl)-6-hydroxy-3,4-dioxonaphthalene-1,8-diolate