L-Proline

L-Proline is an organic compound with the molecular formula C5H9NO2.

Formula
C5H9NO2
Functional group
Amino acids
Molar mass
115.13 g/mol
Also known as
(2S)-pyrrolidine-2-carboxylic acid, proline, L-(-)-Proline, (S)-Pyrrolidine-2-carboxylic acid, (-)-Proline, 2-pyrrolidinecarboxylic acid

Overview

L-Proline is an organic compound with the molecular formula C5H9NO2.

Identifiers

Formula
C5H9NO2
Functional group
Amino acids
Molar mass
115.13 g/mol
Also known as
(2S)-pyrrolidine-2-carboxylic acid, proline, L-(-)-Proline, (S)-Pyrrolidine-2-carboxylic acid, (-)-Proline, 2-pyrrolidinecarboxylic acid
Chemical identifiers
SMILES
C1C[C@H](NC1)C(=O)O
InChI
InChI=1S/C5H9NO2/c7-5(8)4-2-1-3-6-4/h4,6H,1-3H2,(H,7,8)/t4-/m0/s1
PubChem CID
145742

Properties

Melting / decomposition
220-222 °C, decomposes
Water solubility
Solubility in 100 mL of water: 127 g at 0 °C; 162 g at 25 °C; 206.7 g at 50 °C; 239 g at 65 °C
Data availability

Not published: Boiling Point, Density.

Related compounds

  • Amino acids

    L-Proline is an organic compound with the molecular formula C5H9NO2.

References

  1. PubChem Compound Summary: L-Proline (CID 145742)National Center for Biotechnology Information · PubChem

    Identity, molecular formula, molecular weight and aliases retrieved via PUG REST on 2026-09-08.

  2. Hazardous Substances Data Bank (HSDB): L-Proline — melting pointHazardous Substances Data Bank (HSDB)

    Retrieved through PubChem PUG View on 2026-09-08. https://pubchem.ncbi.nlm.nih.gov/compound/145742#section=Melting-Point. Source value, complete property clause or compact miscibility statement retained; absent pressure, temperature or phase conditions are not inferred. Original reference: O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1393

  3. Hazardous Substances Data Bank (HSDB): L-Proline — solubilityHazardous Substances Data Bank (HSDB)

    Retrieved through PubChem PUG View on 2026-09-08. https://pubchem.ncbi.nlm.nih.gov/compound/145742#section=Solubility. Source value, complete property clause or compact miscibility statement retained; absent pressure, temperature or phase conditions are not inferred. Original reference: O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1393