Why does CAS 156-43-4 appear in more than one EU cosmetic annex?

A substance identified by CAS 156-43-4 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 156-43-4?

Use the INCI Checker on CosIng Checker with INCI names, CAS numbers or EC numbers. Paste CAS 156-43-4 to screen it directly, then review every linked annex record and supplier document.

CAS 1 record

CAS 156-43-4

Q: How do I use CAS 156-43-4 for compliance screening?

Cross-reference CAS 156-43-4 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 156-43-4 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 156-43-4

CAS 156-43-4PubChem CID 9076

4-Ethoxyaniline

4-ethoxyaniline is an aromatic ether that is aniline in which the hydrogen at position 4 is replaced by an ethoxy group. It is a hydrolysis metabolite of phenacetin. It has a role as a drug metabolite. It is an aromatic ether, a substituted aniline and a primary amino compound. — ChEBI

IUPAC name: 4-ethoxyaniline

Molecular formula: C8H11NO
Molecular weight: 137.18 g/mol
Exact mass: 137.084063974 Da
XLogP3: 1.2
Topological polar surface area: 35.3 Å²
Hydrogen-bond donors: 1
Hydrogen-bond acceptors: 2
Covalent units: 1
Defined stereocentres: 0

Also known as

p-PhenetidinePhenetidine4-Aminophenetolep-Ethoxyanilinep-Phenetidinp-AminophenetoleBenzenamine, 4-ethoxy-Phenethidine

16 more reported names

1-Amino-4-ethoxybenzeneAniline, p-ethoxy-4-Phenetidine4-AminoethoxybenzeneEthyl p-aminophenol9TSL224ZSECP 5685NSC-3116CHEBI:85505RefChem:858162205-855-5Aminophenetole4-Ethoxybenzenaminep-Aminofenetolp-Fenetidin4-ETHOXY-ANILINE

Open full PubChem record PubChem annotations 3D structure image

External database identifiers

ChEBI:CHEBI:85505
ChEMBL:CHEMBL250969
EPA DTXSID:DTXSID0025864
PubMed:22940574
PubMed:22260423
PubMed:22101594
PubMed:21979970
PubMed:21589619
PubMed:21588270
PubMed:21582579
PubMed:21580427
PubMed:21579529
PubMed:21578305
PubMed:21578299
PubMed:21577967

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 156-43-4

1 total

Annex

Entry

1203

p-Phenetidine (4-Ethoxyaniline)

205-855-5

CMR

How CAS 156-43-4 is used on this site

CAS 156-43-4 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 156-43-4 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 156-43-4 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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