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CAS 1 record

CAS 101-31-5

CAS 101-31-5 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 101-31-5
CAS 101-31-5PubChem CID 154417

Benzeneacetic acid, alpha-(hydroxymethyl)-, (3-endo)-8-methyl-8-azabicyclo(3.2.1)oct-3-yl ester, (alphaS)-

(S)-atropine is an atropine with a 2S-configuration. It is functionally related to a (S)-tropic acid. It is a conjugate base of a (S)-atropinium. — ChEBI

IUPAC name
[(1R,5S)-8-methyl-8-azabicyclo[3.2.1]octan-3-yl] (2S)-3-hydroxy-2-phenylpropanoate
Molecular formula
C17H23NO3
Molecular weight
289.4 g/mol
Exact mass
289.16779360 Da
XLogP3
1.8
Topological polar surface area
49.8 Ų
Hydrogen-bond donors
1
Hydrogen-bond acceptors
4
Covalent units
1
Defined stereocentres
3

Also known as

Benzeneacetic acid, .alpha.-(hydroxymethyl)-, (3-endo)-8-methyl-8-azabicyclo[3.2.1]oct-3-yl ester, (.alpha.S)-Benzeneacetic acid, alpha-(hydroxymethyl)-, (3-endo)-8-methyl-8-azabicyclo[3.2.1]oct-3-yl ester, (alphaS)-BENZENEACETIC ACID, .ALPHA.-(HYDROXYMETHYL)-, (3-ENDO)-8-METHYL-8-AZABICYCLO(3.2.1)OCT-3-YL ESTER, (.ALPHA.S)-RefChem:562898Benzeneacetic acid, .alpha.-(hydroxymethyl)-, (3-endo)-8-methyl-8-azabicyclo3.2.1oct-3-yl ester, (.alpha.S)-Benzeneacetic acid, alpha-(hydroxymethyl)-, (3-endo)-8-methyl-8-azabicyclo3.2.1oct-3-yl ester, (alphaS)-hyoscyamineL-Hyoscyamine
16 more reported names
Daturine(-)-HyoscyamineDuboisine(-)-AtropineL-Tropine tropate(S)-(-)-HyoscyamineCystospazl-Atropine(S)-AtropineHyoscyamine (L)LevsinBellafolineHyoscyaminumAtropine, (s)-ENDO-ATROPINETropine, (-)-tropate
Open full PubChem recordPubChem annotations3D structure image
External database identifiers

Evidence from additional scientific databases

EMBL-EBI ChEBI
Exact identifier matchCHEBI:17486

(S)-atropine

An atropine with a 2S-configuration.

Formula
C17H23NO3
Average mass
289.375 g/mol
Monoisotopic mass
289.16779 Da
Formal charge
0
  • tropan-3α-yl 3-hydroxy-2-phenylpropanoate — is a (CHEBI:78734)
  • (S)-tropic acid — has functional parent (CHEBI:30766)
  • tropan-3α-yl 3-hydroxy-2-phenylpropanoate — is a (CHEBI:78734)
  • (S)-atropinium — is conjugate base of (CHEBI:58164)
Additional curated names
(3-endo)-8-methyl-8-azabicyclo[3.2.1]oct-3-yl (2S)-3-hydroxy-2-phenylpropanoatetropan-3alpha-yl (2S)-3-hydroxy-2-phenylpropanoate[3(S)-endo]-alpha-(hydroxymethyl)benzeneacetic acid 8-methyl-8-azabicyclo[3.2.1]oct-3-yl ester(-)-atropineDaturineDuboisinel-hyoscyamine(-)-hyoscyaminehyoscyamine(S)-(-)-hyoscyamineL-HyoscyamineL-Tropine tropatetropine, (-)-tropate
Cross-references from this source
  • CAS: 101-31-5 — KEGG COMPOUND
  • CAS: 101-31-5 — ChemIDplus
  • CAS: 101-31-5 — NIST Chemistry WebBook
  • MANUAL_X_REF: 1402 — DrugCentral
  • MANUAL_X_REF: C00002293 — KNApSAcK
  • MANUAL_X_REF: C02046 — KEGG COMPOUND
  • MANUAL_X_REF: D00147 — KEGG DRUG
  • MANUAL_X_REF: DB00424 — DrugBank
  • MANUAL_X_REF: OIN — PDBeChem
  • REGISTRY_NUMBER: 91259 — Reaxys

Mapped by: Exact CAS cross-reference in the ChEBI compound record. Source updated: 2017-02-22. Retrieved: 2026-08-31. Open source record

NIH PubChem PUG-View
Exact identifier match154417

Attributed physical-property, hazard, environmental and use annotations.

Mapped by: Existing checksum-valid CAS to unique PubChem CID match. Retrieved: 2026-08-31. Open source record

Scientific classifications and hazard annotations provide context and do not replace the market-specific regulatory decision shown above.

Additional source coverage and match status
SourceResultChecked
EMBL-EBI ChEBIExact match2026-08-31
NIH PubChem PUG-ViewExact match2026-08-31

A recorded no-match is useful evidence that the source was checked; it is not a claim that the substance does not exist elsewhere.

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 101-31-5

1 total

How CAS 101-31-5 is used on this site

CAS 101-31-5 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 101-31-5 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 101-31-5 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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