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1,4-Benzenedisulfonic acid, 2-[2-[4-[2-[4-[2-[1-hydroxy-6-(phenylamino)-3-sulfo-2-naphthalenyl]diazenyl]-1-naphthalenyl]diazenyl]-6-sulfo-1-naphthalenyl]diazenyl]-, sodium salt (1:4)

CAS 2503-73-3

EPA and Census publish no US supply data for this chemical.

Molecular structure of 2503-73-3
4 Na⁺
US productionNot reported
Top sourceNo public record

This chemical is listed as active in US commerce, but no company reported it to EPA’s survey for 2019 or 2023. Sites may have made or imported less than the threshold amount, or none.

Why supply is unknown

Where It Comes From

EPA and Census publish no US supply data for this chemical.

Why It Matters

No EPA sector or FDA product records name a use for this chemical.

Chemical Identity

CAS2503-73-3
PubChem CIDNot recorded
DTXSIDDTXSID0041725
FormulaC42H25N7Na4O13S4
Mol. Weight1055.9 g/mol
SMILES[Na+].[Na+].[Na+].[Na+].OC1=C(N=NC2=CC=C(N=NC3=CC=C(N=NC4=CC(=CC=C4S([O-])(=O)=O)S([O-])(=O)=O)C4=C3C=C(C=C4)S([O-])(=O)=O)C3=C2C=CC=C3)C2=CC(NC3=CC=CC=C3)=CC=C2C=C1S([O-])(=O)=O

Data Sources

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Brief citations

1,4-Benzenedisulfonic acid, 2-[2-[4-[2-[4-[2-[1-hydroxy-6-(phenylamino)-3-sulfo-2-naphthalenyl]diazenyl]-1-naphthalenyl]diazenyl]-6-sulfo-1-naphthalenyl]diazenyl]-, sodium salt (1:4) (CAS 2503-73-3) https://chemicalindependence.com/chemical/2503-73-3/ EPA TSCA Inventory: CAS 2503-73-3. Retrieved 2026-10-04. https://www.epa.gov/tsca-inventory