Is ISOQUERCITRIN safe to use in EU cosmetics?

ISOQUERCITRIN is listed in the EU CosIng ingredient inventory with no direct annex restriction records linked at this time. Always verify against the current official CosIng database before formulating.

What other records share CAS 21637-25-2?

CAS 21637-25-2 may appear across multiple EU annex records. The CAS lookup page shows all Annex II–VI entries sharing this identifier, useful for identifying cross-annex regulatory status of the same chemical substance.

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InventoryRef 3471515/10/2010

ISOQUERCITRIN

2-(3,4-dihydroxyphenyl)-3-(.beta.-D-glucofuranosyloxy)-5,7-dihydroxy-4H-1-benzopyran-4-one

ISOQUERCITRIN is listed in the EU CosIng inventory, but no direct annex records are linked on this page yet.

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Regulatory evidence by market

No rule for this ingredient has been imported for any of the 13 markets tracked here.

That describes this inventory, not the law. No imported rule is not evidence that an ingredient is permitted: a rule may exist under another name or identifier, or in a dataset not yet imported here.

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Chemical identity and properties

PubChem 2D chemical structure for CAS 21637-25-2

CAS 21637-25-2PubChem CID 5484006

Isoquercitrin

Quercetin 3-O-beta-D-glucofuranoside is a quercetin O-glucoside in which a glucofuranosyl residue is attached at position 3 of quercetin via a beta-glycosidic linkage. It has a role as a metabolite. It is a beta-D-glucoside, a tetrahydroxyflavone, a monosaccharide derivative and a quercetin O-glucoside. — ChEBI

IUPAC name: 3-[(2S,3R,4R,5R)-5-[(1R)-1,2-dihydroxyethyl]-3,4-dihydroxyoxolan-2-yl]oxy-2-(3,4-dihydroxyphenyl)-5,7-dihydroxychromen-4-one

Molecular formula: C21H20O12
Molecular weight: 464.4 g/mol
Exact mass: 464.09547607 Da
XLogP3: 0.4
Topological polar surface area: 207.0 Å²
Hydrogen-bond donors: 8
Hydrogen-bond acceptors: 12
Covalent units: 1
Defined stereocentres: 5

Also known as

IsoquercitrosideIsotrifolin0YX10VRV6Jquercetin 3-O-beta-D-glucofuranoside3,3',4',5,7-Pentahydroxyflavone 3-beta-D-glucofuranoside2-(3,4-Dihydroxyphenyl)-3-(beta-D-glucofuranosyloxy)-5,7-dihydroxy-4H-1-benzopyran-4-oneCHEBI:282994H-1-Benzopyran-4-one, 2-(3,4-dihydroxyphenyl)-3-(beta-D-glucofuranosyloxy)-5,7-dihydroxy-

16 more reported names

Flavone, 3,3',4',5,7-pentahydroxy-, 3-beta-D-glucofuranoside2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4-oxo-4H-chromen-3-yl beta-D-glucofuranosideRefChem:5924quercetin 3-(beta-D-glucofuranoside)ISOQUERCETIN ENZYMATICALLY MODIFIED4H-1-benzopyran-4-one, 2-(3,4-dihydroxyphenyl)-3-(beta-D-glucofuranosyloxy)-5,7-dihydroxy2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-3-((2S,4R,5S)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl)oxychromen-4-one244-488-5Isotrifoliin3-(((2S,3R,4R,5R)-5-((R)-1,2-Dihydroxyethyl)-3,4-dihydroxytetrahydrofuran-2-yl)oxy)-2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4H-chromen-4-oneC21H20O12CCRIS 70933-[[(2S,3R,4R,5R)-5-[(R)-1,2-Dihydroxyethyl]-3,4-dihydroxytetrahydrofuran-2-yl]oxy]-2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4H-chromen-4-oneEINECS 244-488-5quercetin 3-O-|A-D-glucofuranosideUNII-0YX10VRV6J

Open full PubChem record PubChem annotations 3D structure image

External database identifiers

ChEBI:CHEBI:28299
EPA DTXSID:DTXSID80904976
PubMed:17003167
PubMed:10852961

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

Inventory details for ISOQUERCITRIN

INCI name

ISOQUERCITRIN

Description

2-(3,4-dihydroxyphenyl)-3-(.beta.-D-glucofuranosyloxy)-5,7-dihydroxy-4H-1-benzopyran-4-one

Record provenance

Inventory reference: 34715
Imported identity: ISOQUERCITRIN
Source update: 15/10/2010

European Commission CosIng source notes

Annex records for ISOQUERCITRIN

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Key data

CAS

21637-25-2

244-488-5

Restriction

—

Function

ANTIOXIDANT: Inhibiting reactions promoted by oxygen, thus avoiding oxidation and rancidity.

Official EU ingredient-name evidence

The ingredient name exactly matches the official 2025 EU glossary of common ingredient names.

#13899 · ISOQUERCITRIN

Ingredients with overlapping formulation functions

ISOMERIZED LINOLEYL GALLATEANTIOXIDANT, SKIN CONDITIONING, SKIN CONDITIONING - EMOLLIENT, SKIN PROTECTING

ISOOCTYL CAPRYLATE/CAPRATEANTIOXIDANT, PLASTICISER, SKIN CONDITIONING, SKIN CONDITIONING - EMOLLIENT

ISOPROPYLCHROMENAMIDO FLUOROBENZYL METHANESULFONAMIDEANTIOXIDANT, BLEACHING, SKIN PROTECTING

ISOQUERCETINANTIOXIDANT

ISOTRIACONTANEANTIOXIDANT, ASTRINGENT, HAIR CONDITIONING, HUMECTANT, SKIN CONDITIONING - EMOLLIENT, SKIN CONDITIO…

JACARANDA CAUCANA LEAF EXTRACTANTIMICROBIAL, ANTIOXIDANT

JACARANDA MIMOSIFOLIA FLOWER EXTRACTANTIOXIDANT, HAIR CONDITIONING, SKIN CONDITIONING

JACOBAEA VULGARIS EXTRACTANTIOXIDANT

Additional official and scientific sources

11 external databases to check this identity in

Each link searches that source for this identity. What each source is, and its legal weight

ECHA CHEM / Information on chemicals PubChem PUG REST EU Safety Gate cosmetic product alerts ECHA CHEM US EPA CompTox Cosmetic Ingredient Review safety assessments FDA Global Substance Registration System ILO/WHO International Chemical Safety Cards Japan NITE-CHRIP NIOSH Pocket Guide to Chemical Hazards OECD eChemPortal

How ISOQUERCITRIN appears in the CosIng inventory

The CosIng inventory lists ISOQUERCITRIN as a cosmetic ingredient and this page links it to 0 annex records. The inventory entry captures names and identifiers, while the annex records show where the substance is prohibited, restricted or positively listed in EU cosmetics law.

ISOQUERCITRIN is also tagged with 1 cosmetic function in the official data. Function labels describe intended use, but they do not replace regulatory review of linked annex records before formulation or labelling work.

Frequently asked questions

ISOQUERCITRIN is listed in the EU CosIng ingredient inventory with no direct annex restriction records linked at this time. Absence of an annex link does not guarantee unrestricted use — always verify against the current official CosIng database before formulating.

According to the EU CosIng inventory, ISOQUERCITRIN carries the following function designation(s):

ANTIOXIDANT

CAS 21637-25-2 may appear across multiple EU annex records. Viewing the CAS lookup page shows all Annex II–VI entries sharing this identifier, which is useful for identifying cross-annex regulatory status of the same chemical substance.

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Source note for ISOQUERCITRIN

This page reproduces the CosIng inventory entry for ISOQUERCITRIN from public European Commission cosmetic ingredient materials and shows linked identifiers even when no direct annex match is currently attached.

Use this inventory page to research ISOQUERCITRIN and compare linked records, but verify restrictions and legal status against the current official source text and law before making regulatory decisions.

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