The molecule is an organic sodium salt that is the monosodium salt of 4-amino-1,3-dihydroxy-9,10-dioxo-9,10-dihydroanthracene-2-sulfonic acid. It forms bright red lakes with calcium and is a useful red nuclear staining lake with aluminum. It has a role as a histological dye and a fluorochrome. It contains a nuclear fast red(1-).
sodium;4-amino-1,3-dihydroxy-9,10-dioxoanthracene-2-sulfonate