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Annex II Entry 152 20/10/2010

Inproquone (INN)

Inproquone (INN) 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: 152

Chemical identity and properties

PubChem 2D chemical structure for CAS 436-40-8
CAS 436-40-8PubChem CID 71627

Inproquone

Inproquone is a benzoquinone-based antineoplastic agent. Inproquone was never marketed. — NCI Thesaurus (NCIt)

IUPAC name
2,5-bis(aziridin-1-yl)-3,6-dipropoxycyclohexa-2,5-diene-1,4-dione
Molecular formula
C16H22N2O4
Molecular weight
306.36 g/mol
Exact mass
306.15795719 Da
XLogP3
2.0
Topological polar surface area
58.6 Ų
Hydrogen-bond donors
0
Hydrogen-bond acceptors
6
Covalent units
1
Defined stereocentres
0

Also known as

InproquonumRP 6870inprocuonaNSC-17261E-39 (INPROQUONE)RP-6870C6Y700V0M4inprochon
16 more reported names
RefChem:148390CytostaticumZytostatikaBayer E 39E 392,5-Bis(ethyleneimino)-3,6-dipropoxy-1,4-benzoquinone2,5-Bis(ethyleneimino)-3,6-dipropoxy-p-benzoquinoneCytostatikaInprochonumNSC 17261;E 39;RP 6870Improcuona [INN-Spanish]ImprocuonaInproquone [INN:BAN]Inproquonum [INN-Latin]NSC 172616870 RP
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

Inproquone (INN)

Chemical / IUPAC name

2,5-Bis(ethyleneimino)-3,6-dipropoxy-p-benzoquinone

Regulatory information

Regulation

(EC) 2009/1223

See every entry this act set

Key data

CAS
436-40-8
EC
—
Annex
II
Entry number
152

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

Annex II 151
Nearby record in the same annex

Dinitrophenol isomers

CAS: 51-28-5 / 329-71-5 / 573-56-8 / 25550-58-7
EC: 200-087-7 / 206-348-1 / 209-357-9 / 247-096-2
Annex II 150
Nearby record in the same annex

Succinonitrile

CAS: 110-61-2
EC: 203-783-9
Annex II 149
Nearby record in the same annex

Malononitrile

CAS: 109-77-3
EC: 203-703-2

What Annex II means for Inproquone (INN)

Inproquone (INN) 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. Inproquone (INN) 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 436-40-8 is the unique numerical identifier assigned to Inproquone (INN) 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 Inproquone (INN)

This page summarizes one Annex II record for Inproquone (INN) 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 Inproquone (INN), but confirm any final regulatory decision against the current official annex wording and source files.

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