1-Amino-4-hydroxy-2-[4-[(2-methylphenyl)sulfonyloxy]phenoxy]anthracene-9,10-dione

4-[(1-amino-9,10-dihydro-4-hydroxy-9,10-dioxo-2-anthryl)oxy]phenyl o-toluenesulphonate

2-Methylbenzenesulfonic acid 4-[[(1-amino-9,10-dihydro-4-hydroxy-9,10-dioxoanthracen)-2-yl]oxy]phenyl ester