The molecule is dianion of 3,3'-biflaviolin arising from selective deprotonation of the OH groups at the 2- and 2'-positions. It is a conjugate base of a 3,3'-biflaviolin. It is a conjugate acid of a 3,3'-biflaviolin(3-).
2-(6,8-dihydroxy-1-oxido-3,4-dioxonaphthalen-2-yl)-6,8-dihydroxy-3,4-dioxonaphthalen-1-olate