# L-Isoleucine

**CAS:** 73-32-5  
**PubChem CID:** [6306](https://pubchem.ncbi.nlm.nih.gov/compound/6306)  
**Molecular formula:** C6H13NO2  
**Molar mass:** 131.17 g/mol  
**IUPAC:** (2S,3S)-2-amino-3-methylpentanoic acid  
**SMILES:** `CC[C@H](C)[C@@H](C(=O)O)N`  
**InChIKey:** `AGPKZVBTJJNPAG-WHFBIAKZSA-N`  
**InChI:** `InChI=1S/C6H13NO2/c1-3-4(2)5(7)6(8)9/h4-5H,3,7H2,1-2H3,(H,8,9)/t4-,5-/m0/s1`  

## Physicochemical properties

| Parameter | Value |
|---|---|
| logP (XLogP3) | -1.7 |
| PSA | 63.3 Ų |
| Hydrogen bond donors | 2 |
| Hydrogen bond acceptors | 3 |
| Rotatable bonds | 3 |
| Heavy atoms | 9 |

## 3D structure

The molecule contains 22 atoms connected by 21 chemical bonds. Interactive 3D model available at: https://molgod.org/molecule/73-32-5/

## Synonyms

- l-isoleucine
- Isoleucine
- 73-32-5
- (2S,3S)-2-Amino-3-methylpentanoic acid
- 2S,3S-Isoleucine
- (S)-Isoleucine
- (S,S)-Isoleucine
- 2-Amino-3-methylvaleric acid
- erythro-L-Isoleucine
- L-Ile

## Data sources

- [PubChem CID 6306](https://pubchem.ncbi.nlm.nih.gov/compound/6306)
- [Wikidata](https://www.wikidata.org/wiki/Q484940)
- [NIST WebBook](https://webbook.nist.gov/cgi/cbook.cgi?ID=73-32-5)
- [ChEMBL](https://www.ebi.ac.uk/chembl/g/#search_results/all/query=73-32-5)

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*Last updated: 2026-09-25 · Generator: MOL-GOD v3.12.33*