Sodium indigo sulfonate;UNII-91197VC7OT;27414-69-3;91197VC7OT;Sodium salt of 2-(1,3-dihydro-3-oxo-2H-indol-2-ylidene)- 2,3-dihydro-3-oxo-1H-indole-5-sulfonic acid;Sodium salt of 2-(1,3-dihydro-3-oxo-2H-indol-2-ylidene)-2,3-dihydro-3-oxo-1H-indole-5-sulfonic acid;DTXSID50181838;SODIUM INDIGO-5-SULFONATE;Q27271357;sodium;3-hydroxy-2-(3-oxoindol-2-yl)-1H-indole-5-sulfonate