potassium hydrogen 9,10-dihydro-1,5-dihydroxy-4,8-dinitro-9,10-dioxoanthracene-2,6-disulphonate

9,10-Dihydro-1,5-dihydroxy-4,8-dinitro-9,10-dioxo-2,6-anthracenedisulfonic acid 2-potassium salt