m-tolyl p-[(1-amino-9,10-dihydro-4-hydroxy-9,10-dioxo-2-anthryl)oxy]benzenesulphonate

4-[(1-Amino-9,10-dihydro-4-hydroxy-9,10-dioxoanthracen-2-yl)oxy]benzenesulfonic acid 3-methylphenyl ester