L-Ornithine

Description

L-Ornithine · CAS 70-26-8 · C5H12N2O2. UNII E524N2IXA3. Melting Point: 140; Melting Point: 140 °C; Solubility: 620 mg/mL.

Identification

CAS Registry Number	70-26-8
PubChem CID	6262
Molecular formula	C5H12N2O2
IUPAC name	(2S)-2,5-diaminopentanoic acid
UNII (FDA)	E524N2IXA3

Computed Descriptors

Molecular Weight	132.16
XLogP3	-4.4
Hydrogen Bond Donor Count	3
Hydrogen Bond Acceptor Count	4
Rotatable Bond Count	4
Exact Mass	132.089877630
Monoisotopic Mass	132.089877630
Topological Polar Surface Area	89.3
Heavy Atom Count	9
Formal Charge	0

Physical & Chemical Properties

Melting Point	140
Melting Point	140 °C
Solubility	620 mg/mL
LogP	-4.22
Dissociation Constants	1.94 (at 25 °C)

Physical description & handling notes

• Colorless solid; [Merck Index]
• Solid
• Appreciable
• 127.7 Ų [M+H]+ [CCS Type: DT; Method: single field calibrated with ESI Low Concentration Tuning Mix (Agilent)]
• 129.79 Ų [M+H]+ [CCS Type: DT; Method: stepped-field]
• 136.8 Ų [M-H]- [CCS Type: DT; Method: stepped-field]

Regulatory Status

Regulatory & Food Contact	CIR / INCI: Skin conditioning
GHS notification summary	100% (6 / 6)

GHS Hazard Classification

GHS notification summary	100% (6 / 6)

Documented Uses

• A non-essential amino acid; Has been used in the treatment of hyperammonemia; [Merck Index]
• Use (kg; approx.) in Germany (2009): >25000
• Consumption (g per capita; approx.) in Germany (2009): 0.305
• Used for nutritional supplementation, also for treating dietary shortage or imbalance. It has been claimed that ornithine improves athletic performance, has anabolic effects, has wound-healing effects, and is immuno-enhancing.
• Absorbed from the small intestine via a sodium-dependent active transport process
• Ornithine undergoes extensive metabolism in the liver to L-arginine, polyamines, and proline, and several other metabolites.

Synonyms

L-ornithine; ornithine; 70-26-8; (S)-2,5-Diaminopentanoic acid; (S)-Ornithine; (S)-2,5-diaminovaleric acid; (2S)-2,5-diaminopentanoic acid; (S)-alpha,delta-Diaminovaleric acid; Ornitina; (+)-S-Ornithine; Ornithinum; (S)-2,5-Diaminopentanoate; L-(-)-Ornithine; NSC-758894; E524N2IXA3; CHEBI:15729

Frequently Asked Questions

What are the CAS number and molecular formula of L-Ornithine?

CAS 70-26-8; molecular formula C5H12N2O2; molecular weight — g/mol.

What other names is L-Ornithine known by?

L-ornithine, ornithine, 70-26-8, (S)-2,5-Diaminopentanoic acid, (S)-Ornithine, (S)-2,5-diaminovaleric acid.

What is the regulatory status of L-Ornithine?

Documented regulatory listings: CIR / INCI: Skin conditioning.

Is L-Ornithine classified as hazardous?

100% of GHS notifications report no hazard classification (6 of 6).

What are the key physical properties of L-Ornithine?

Melting Point: 140; Melting Point: 140 °C; Solubility: 620 mg/mL; LogP: -4.22.

Facts on this page are taken from PubChem (US National Library of Medicine) and Wikidata. Grade-specific data — assay, moisture, particle size, packaging, shelf life — is issued per batch on the COA and is not published here.