Hexane-2,5-dione
| Hexane-2,5-dione | |
|---|---|
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| Other names 1,2-diacetylethane | |
| Identifiers | |
| CAS number | 110-13-4  |
| PubChem | 8035 |
| ChemSpider | 7744 |
| RTECS number | MO3150000 |
| Jmol-3D images | Image 1 |
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| Properties | |
| Molecular formula | C6H10O2 |
| Molar mass | 114.1438 g mol−1 |
| Appearance | colorless liquid |
| Density | 0.973 g cm−3, liquid |
| Melting point | −5.5 °C; 22.1 °F; 267.6 K |
| Boiling point | 191.4 °C; 376.5 °F; 464.5 K |
| Solubility in water | ≥ 10 g/100 mL (22 °C) |
| Structure | |
| Molecular shape | trigonal planar at carbonyl tetrahedral elsewhere |
| Hazards | |
| Flash point | 78 °C; 172 °F; 351 K |
| Related compounds | |
| Related diketones | acetylacetone |
(verify) (what is: / ?)Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa) | |
| Infobox references | |
Hexane-2,5-dione is an organic compound with the formula [CH3COCH2]2. This colorless liquid is classified as a diketone. It is a toxic metabolite of hexane.[1]
Symptoms
The initial symptoms of chronic hexane toxicity, attributable to hexane-2,5-dione, are tingling and cramps in the arms and legs, followed by general muscular weakness. In severe cases, atrophy of the skeletal muscles is observed, along with a loss of coordination and problems of vision.[2]
Similar symptoms are observed in animal models. They are associated with a degeneration of the peripheral nervous system (and eventually the central nervous system), starting with the distal portions of the longer and wider nerve axons.
Mechanism of action
Hexane-2,5-dione reacts with the amines to give pyrroles. Similarly it reacts with the amine groups of the side chain of lysine residues in proteins, causing cross-linking and a loss of protein function.
The lone pair on the nitrogen attacks either of the electron deficient carbonyl carbons, forming a tetrahedral hemiaminal intermediate. A heterocyclic structure is formed as the second carbonyl carbon is attacked and a 2,5-dihydroxytetrafuran forms, akin to the Paal-Knorr pyrrole synthesis. Two water molecules are expelled, creating an aromatic 2,5-dimethylpyrrole moiety. Further oxidation of the pyrrole moiety can lead to crosslinking.[3]
Related metabolytes
Hexane-2,5-dione can be dehydrated to 2,5-dimethylfuran.
References
- ↑ Carelli et al 2007 ENVIRONMENTAL HEALTH PERSPECTIVES volume 115, pages 113-115
- ↑ Couri D, Milks M. "Toxicity and metabolism of the neurotoxic hexacarbons n-hexane, 2-hexanone, and 2,5-hexanedione" Annual Rev. Pharmacol. Toxicol. 1982;22:145-66.
- ↑ LoPachin et al 2009 Journal of Toxicology and Environmental Health, Part A volume 72, pages 861-869