2,2'-[(9,10-dihydro-9,10-dioxo-1,5-anthrylene)bis(thio)]bisbenzoic acid

2,2'-[(9,10-Dihydro-9,10-dioxoanthracene-1,5-diyl)bisthio]bisbenzoic acid

2,2'-[[(9,10-Dihydro-9,10-dioxoanthracene)-1,5-diyl]bis(thio)]bisbenzoic acid