9,10-Dihydro-1,8-dihydroxy-4,5-dinitro-9,10-dioxo-2,7-anthracenedisulfonic acid

1,8-Dihydroxy-4,5-dinitro-9,10-dihydro-9,10-dioxoanthracene-2,7-disulfonic acid

9,10-dihydro-1,8-dihydroxy-4,5-dinitro-9,10-dioxoanthracene-2,7-disulphonic acid