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Annex II Entry 443 20/10/2010

4-(4-Methoxyphenyl)-3-butene-2-one (Anisylidene acetone), when used as a fragrance ingredient

4-(4-Methoxyphenyl)-3-butene-2-one (Anisylidene acetone), when used as a fragrance ingredient is listed in Annex II as a prohibited substance for cosmetic products placed on the EU market.

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Prohibited substance— Annex II, EU Regulation 1223/2009
Entry: 443

Chemical identity and properties

PubChem 2D chemical structure for CAS 943-88-4
CAS 943-88-4PubChem CID 736889

p-Methoxybenzylideneacetone

IUPAC name
(E)-4-(4-methoxyphenyl)but-3-en-2-one
Molecular formula
C11H12O2
Molecular weight
176.21 g/mol
Exact mass
176.083729621 Da
XLogP3
2.1
Topological polar surface area
26.3 Ų
Hydrogen-bond donors
0
Hydrogen-bond acceptors
2
Covalent units
1
Defined stereocentres
0

Also known as

1-(p-Methoxyphenyl)-1-buten-3-one3815-30-34-(4-Methoxyphenyl)-3-buten-2-onep-Anisalacetone4-MethoxybenzalacetoneAnisalacetone4-Methoxybenzylideneacetonep-Methoxybenzalacetone
16 more reported names
Methyl p-methoxystyryl ketone3-Buten-2-one, 4-(4-methoxyphenyl)-4'-Methoxybenzylideneacetonep-Methoxystyryl methyl ketone4-Methoxystyryl methyl ketone3-Buten-2-one, 4-(p-methoxyphenyl)-trans-4-MethoxybenzalacetoneNSC 79464-(p-Methoxyphenyl)-3-buten-2-oneMethyl-p-methoxycinnamylketoneNSC 317524-(p-Methoxyphenyl)-3-butene-2-oneAnisylidene acetoneEINECS 213-404-9BRN 152553579U9LYF10I
Open full PubChem recordPubChem annotations3D structure image
External database identifiers

Retrieved from NIH PubChem on 2026-09-02 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.

Record details

Chemical name

4-(4-Methoxyphenyl)-3-butene-2-one (Anisylidene acetone), when used as a fragrance ingredient

Regulatory information

Regulation

(EC) 2009/1223

See every entry this act set

SCCS opinions

Key data

CAS
943-88-4
EC
213-404-9
Annex
II
Entry number
443

Direct matches are limited for this record, so nearby entries from Annex II are shown as well.

What Annex II means for 4-(4-Methoxyphenyl)-3-butene-2-one (Anisylidene acetone), when used as a fragrance ingredient

4-(4-Methoxyphenyl)-3-butene-2-one (Anisylidene acetone), when used as a fragrance ingredient is listed as a prohibited substance under Annex II of EU Cosmetics Regulation 1223/2009 and must not be intentionally added. Article 17 separately addresses unintended small quantities that are technically unavoidable under good manufacturing practice and compatible with the Article 3 safety requirement.

Formulators must screen their ingredients and raw materials to ensure none contain this substance. Suppliers should provide documentation confirming absence when requested.

The page also surfaces 12 related annex records with overlapping identifiers, annex logic or naming patterns.

Compliance checklist

  • Verify this substance is absent from all raw materials and finished formulations.
  • Request absence confirmation or CoA from raw material suppliers.
  • Document the screening result in the Product Information File (PIF).

Frequently asked questions

Yes. 4-(4-Methoxyphenyl)-3-butene-2-one (Anisylidene acetone), when used as a fragrance ingredient is listed in Annex II of EU Cosmetics Regulation 1223/2009 and is prohibited as an intentionally added cosmetic ingredient. Article 17 provides a narrow exception for unintended small quantities that are technically unavoidable under good manufacturing practice, provided the product remains safe under Article 3.

CAS 943-88-4 is the unique numerical identifier assigned to 4-(4-Methoxyphenyl)-3-butene-2-one (Anisylidene acetone), when used as a fragrance ingredient by the Chemical Abstracts Service. In cosmetic compliance work, the CAS number is used to cross-reference the substance across regulatory databases, raw material specifications and safety assessment reports. Multiple EU annex entries may share the same CAS number if the same substance appears under different conditions or in different annexes.

Use the INCI Checker tool on this site to paste your full ingredient list (INCI) and scan it against all Annex II–VI entries. The tool highlights any ingredients that match restricted, prohibited or allergen-flagged records. This is useful for rapid compliance screening of finished product formulas or raw material declarations.
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Source note for Annex II record 4-(4-Methoxyphenyl)-3-butene-2-one (Anisylidene acetone), when used as a fragrance ingredient

This page summarizes one Annex II record for 4-(4-Methoxyphenyl)-3-butene-2-one (Anisylidene acetone), when used as a fragrance ingredient from public European Commission cosmetic materials and adds linked inventory or identifier matches when available.

Use this record page to review Annex II conditions for 4-(4-Methoxyphenyl)-3-butene-2-one (Anisylidene acetone), when used as a fragrance ingredient, but confirm any final regulatory decision against the current official annex wording and source files.

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