CI 45430
Disodium 2-(2,4,5,7-tetraiodo-6-oxido-3-oxoxanthen-9-yl)benzoate monohydrate
Disodium; 2′,4′,5′,7′-tetraiodo-3-oxospiro[2-benzofuran-1,9′-xanthene]-3′,6′-diolate
Disodium 2′,4′,5’,7′-tetraiodofluorescein monohydrate
Class: Xanthene C20H6O5I4Na2 Formula wt: 879.86
127 [16423-68-0] PN2ZH5LOQY fd&c red no. 3
DESCRIPTION
Erythrosine occurs as red to brown powder or granules. It is principally the disodium salt of the monohydrate of 9-(o-carboxyphenyl)-6-hydroxy-2,4,5,7-tetraiodo-3H-xanthen-3-one. Erythrosine is manufactured by iodination of fluorescein, the condensation product of resorcinol and phthalic anhydride. When dissolved in water, it yields a solution that is red at neutrality, a yellow-brown precipitate in acid, and a red precipitate in the base. When dissolved in concentrated sulfuric acid, it yields a brown-yellow solution that evolves iodine and a precipitate of the free acid when heated. It is insoluble in ethanol.