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CAS 51-35-4

CAS 51-35-4 matches 0 EU annex records across Annex II–VI of Regulation 1223/2009.

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Chemical identity and properties

PubChem 2D chemical structure for CAS 51-35-4
CAS 51-35-4PubChem CID 5810

L-Hydroxyproline

Trans-4-hydroxy-L-proline is an optically active form of 4-hydroxyproline having L-trans-configuration. It has a role as a mouse metabolite, a plant metabolite and a human metabolite. It is a tautomer of a trans-4-hydroxy-L-proline zwitterion. — ChEBI

IUPAC name
(2S,4R)-4-hydroxypyrrolidine-2-carboxylic acid
Molecular formula
C5H9NO3
Molecular weight
131.13 g/mol
Exact mass
131.058243149 Da
XLogP3
-3.3
Topological polar surface area
69.6 Ų
Hydrogen-bond donors
3
Hydrogen-bond acceptors
4
Covalent units
1
Defined stereocentres
2

Also known as

trans-4-Hydroxy-L-prolinehydroxyprolineHyprohydroxy-L-proline(4R)-4-hydroxy-L-prolinetrans-L-HydroxyprolineL-Proline, 4-hydroxy-, (4R)-trans-Hydroxyproline
16 more reported names
4-Hydroxy-2-pyrrolidinecarboxylic aciddelta-HydroxyprolineL-Proline, 4-hydroxy-, trans-(2S,4R)-4-hydroxyprolineRMB44WO89XLUMISTORL-threo-4-hydroxyprolineNSC-46704(2S,4R)-4-hydroxy-2-pyrrolidinecarboxylic acidCHEBI:18095[2S,4R]-4-HYDROXY-2-PYRROLIDINECARBOXYLIC ACIDCHEBI:18240oxyproline(2S,4R)-4-hydroxypyrrolidin-1-ium-2-carboxylateNMH-Procis 4 Hydroxyproline
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External database identifiers

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 51-35-4

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How CAS 51-35-4 is used on this site

CAS 51-35-4 is the Chemical Abstracts Service identifier used to pin this page to a specific substance. In the current dataset, 0 EU annex records share 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 51-35-4 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.