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CAS 1 record

CAS 2610-11-9

CAS 2610-11-9 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 2610-11-9
CAS 2610-11-9PubChem CID 17462

C.I. Direct Red 81 disodium salt

Sirius red 4B is an organic sodium salt resulting from the formal condensation of Sirius red 4B (acid form) with two equivalents of sodium hydroxide. Used as the plasma stain in some trichrome staining methods. It has a role as a fluorochrome, a poison, a histological dye and an environmental contaminant. It contains a Sirius red 4B(2-). — ChEBI

IUPAC name
disodium;7-benzamido-4-hydroxy-3-[[4-[(4-sulfonatophenyl)diazenyl]phenyl]diazenyl]naphthalene-2-sulfonate
Molecular formula
C29H19N5Na2O8S2
Molecular weight
675.6 g/mol
Exact mass
675.04704349 Da
Topological polar surface area
230.0 Ų
Hydrogen-bond donors
2
Hydrogen-bond acceptors
12
Covalent units
3
Defined stereocentres
0

Also known as

RefChem:1080560DIRECT RED 81Chlorantine Fast Red 5BSolaminrot 4BAiredale Red KDC.I. Direct Red 81Sirius Red 4BCalcodur Red 8BL
16 more reported names
Triantine Light Red 4BNCHLORANTINEFASTRED5BDirect Fast Red 5BBordeaux EMBLSaturn Red BSolar Red BDurazol Red 2BDurazol Red 2BPFenaluz Red 4BSumilight Red 4BSuprazo Red 4BEliamina Red 8BLHelion Red 8BHispaluz Red 8BLSirius Red 4BASolius Red 4B
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External database identifiers

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 2610-11-9

1 total

How CAS 2610-11-9 is used on this site

CAS 2610-11-9 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 2610-11-9 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 2610-11-9 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.

The INCI Checker accepts ingredient names, CAS numbers and EC numbers. Check this CAS number directly, then verify the result against supplier specification sheets and every linked annex condition.
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