Why does CAS 55-65-2 appear in more than one EU cosmetic annex?

A substance identified by CAS 55-65-2 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 55-65-2?

Use the INCI Checker on CosIng Checker with INCI names, CAS numbers or EC numbers. Paste CAS 55-65-2 to screen it directly, then review every linked annex record and supplier document.

CAS 1 record

CAS 55-65-2

Q: How do I use CAS 55-65-2 for compliance screening?

Cross-reference CAS 55-65-2 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 55-65-2 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 55-65-2

CAS 55-65-2PubChem CID 3518

Guanethidine

Guanethidine is a member of the class of guanidines in which one of the hydrogens of the amino group has been replaced by a 2-azocan-1-ylethyl group. It has a role as an antihypertensive agent, an adrenergic antagonist and a sympatholytic agent. It is a member of guanidines and a member of azocanes. It is functionally related to a guanidine. It derives from a hydride of an azocane. — ChEBI

IUPAC name: 2-[2-(azocan-1-yl)ethyl]guanidine

Molecular formula: C10H22N4
Molecular weight: 198.31 g/mol
Exact mass: 198.18444672 Da
XLogP3: 0.5
Topological polar surface area: 67.6 Å²
Hydrogen-bond donors: 2
Hydrogen-bond acceptors: 2
Covalent units: 1
Defined stereocentres: 0

Also known as

AbapresinSanotensinEutensolOktadinOctatensineOktatensinOktatenzinDopom

16 more reported names

GuanetidinaOctadineGuanethidinum2-(1'-Azacyclooctyl)ethylguanidineN-(2-Perhydroazocin-1-ylethyl)guanidineAzocine, 1-(2-guanidinoethyl)octahydro-2-(1-N,N-Heptamethyleneimino)ethylguanidineGuanidine, (2-(hexahydro-1(2H)-azocinyl)ethyl)-(2-(Octahydro-1-azocinyl)ethyl)guanidine1-[2-(azocan-1-yl)ethyl]guanidineHeptamethylenimine, 1-(2-guanidinoethyl)-ZTI6C33Q2Q1-(2-(Azocan-1-yl)ethyl)guanidineAzocine, 1-((2-(aminoiminomethyl)amino)ethyl)octahydro-CHEBI:5557(2-(hexahydro-1(2h)-azocinyl)ethyl)guanidine

Open full PubChem record PubChem annotations 3D structure image

External database identifiers

ChEBI:CHEBI:5557
ChEMBL:CHEMBL765
EPA DTXSID:DTXSID5023116
PubMed:23058054
PubMed:22994938
PubMed:22853187
PubMed:22785022
PubMed:22752269
PubMed:22701081
PubMed:22666386
PubMed:22611415
PubMed:22540017
PubMed:22510969
PubMed:22473744
PubMed:22450195

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 55-65-2

1 total

Annex

Entry

259

Guanethidine (INN) and its salts

200-241-3

How CAS 55-65-2 is used on this site

CAS 55-65-2 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 55-65-2 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 55-65-2 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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