Why does CAS 5413-75-2 appear in more than one EU cosmetic annex?

A substance identified by CAS 5413-75-2 may appear in multiple EU cosmetic regulation annexes when it is subject to different conditions in different contexts — for example, restricted under Annex III with specific conditions, while also appearing in Annex IV as an approved colorant under separate entry conditions. Each entry must be reviewed individually.

How do I check if my formula contains a substance with CAS 5413-75-2?

Use the INCI Checker on CosIng Checker with INCI names, CAS numbers or EC numbers. Paste CAS 5413-75-2 to screen it directly, then review every linked annex record and supplier document.

CAS 1 record

CAS 5413-75-2

Q: How do I use CAS 5413-75-2 for compliance screening?

Cross-reference CAS 5413-75-2 against your raw material specification sheets and CoA documents. When it appears in Annex II, verify absence. When it appears in Annex III, verify that concentration limits and product type conditions are met. All annex entries sharing this CAS number are listed on this page.

CAS 5413-75-2 matches 1 EU annex record across Annex II–VI of Regulation 1223/2009.

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Chemical identity and properties

PubChem 2D chemical structure for CAS 5413-75-2

CAS 5413-75-2PubChem CID 21519

1,3-naphthalenedisulfonic acid, 7-hydroxy-8-((4-(phenylazo)phenyl)azo)-, disodium salt

Woodstain scarlet is an organic sodium salt that is the disodium salt of 7-hydroxy-8-{[4-(phenyldiazenyl)phenyl]diazenyl}naphthalene-1,3-disulfonic acid. Occasionally used for the demonstration of muscle fibres in conjunction with, or as a replacement for, acid fuchsin. It has a role as a histological dye. It contains a 7-hydroxy-8-{[4-(phenyldiazenyl)phenyl]diazenyl}naphthalene-1,3-disulfonate. — ChEBI

IUPAC name: disodium;7-hydroxy-8-[(4-phenyldiazenylphenyl)diazenyl]naphthalene-1,3-disulfonate

Molecular formula: C22H14N4Na2O7S2
Molecular weight: 556.5 g/mol
Exact mass: 556.00992971 Da
Topological polar surface area: 201.0 Å²
Hydrogen-bond donors: 1
Hydrogen-bond acceptors: 11
Covalent units: 3
Defined stereocentres: 0

Also known as

Sodium 6-hydroxy-5-(4-phenylazophenylazo)naphthalene-2,4-disulphonate1,3-Naphthalenedisulfonic acid, 7-hydroxy-8-[[4-(phenylazo)phenyl]azo]-, disodium saltRefChem:4153691,3-Naphthalenedisulfonic acid, 7-hydroxy-8-4-(phenylazo)phenylazo-, disodium saltACID RED 73Brilliant croceinWoodstain ScarletC.I. Acid Red 73

16 more reported names

Crocein Scarlet MOOCrocein Scarlet 3BBrilliant Crocein MOOC.I. Acid Red 73, disodium saltBrilliant Croceine MOOC.I. 272905PLA82FV3CCI 272907-Hydroxy-8-((4-(phenylazo)phenyl)azo)-1,3-naphthalenedisulfonic acid, disodium salt1,3-Naphthalenedisulfonic acid, 7-hydroxy-8-(2-(4-(2-phenyldiazenyl)phenyl)diazenyl)-, sodium salt (1:2)1,3-Naphthalenedisulfonic acid, 7-hydroxy-8-[2-[4-(2-phenyldiazenyl)phenyl]diazenyl]-, sodium salt (1:2)NSC-7832NSC-47724UNII-5PLA82FV3CBrilliant Scarlet R (VAN)Brilliantcroceine

Open full PubChem record PubChem annotations 3D structure image

External database identifiers

ChEBI:CHEBI:87189
EPA DTXSID:DTXSID1041712

Retrieved from NIH PubChem on 2026-08-31 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.

Records for CAS 5413-75-2

1 total

Annex

Entry

1233

Acid Red 73 (CI 27290), when used as a substance in hair dye products

226-502-1

How CAS 5413-75-2 is used on this site

CAS 5413-75-2 is the Chemical Abstracts Service identifier used to pin this page to a specific substance. In the current dataset, 1 EU annex record shares this identifier, which helps you cross-check whether the same substance appears under one regulatory context or several.

Use this page when a supplier specification, SDS or raw-material dossier gives you CAS 5413-75-2 and you need to see every linked Annex II–VI record in one place. The entry cards above are the quickest route to concentration limits, warnings, annex placement and product-type conditions.

Frequently asked questions

A substance identified by CAS 5413-75-2 may appear in multiple EU cosmetic regulation annexes when it is subject to different conditions in different contexts. For example, a substance might be restricted under Annex III with specific conditions, and the same CAS might also appear in Annex IV as an approved colorant under separate entry conditions. Each entry must be reviewed individually.

Cross-reference the CAS number against your raw material specification sheets and CoA documents. When a CAS appears in Annex II, verify absence. When it appears in Annex III, verify that concentration limits and product type conditions are met in your formulation. All annex entries sharing this CAS number are listed above.

A CAS number is assigned by the Chemical Abstracts Service (USA) and is globally recognised. An EC number is a European Commission identifier from inventories such as EINECS, ELINCS or the NLP list. Both identifiers may appear in EU cosmetic annex entries. Some substances have both, some have only one, and some older entries may have neither.

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