Alloxan[1]
IUPAC name	1,3-Diazinane-2,4,5,6-tetrone
Other names	Mesoxalylurea 5-Oxobarbituric acid
Identifiers
CAS number	50-71-5 N, 2244-11-3 (Monohydrate)
PubChem	5781
MeSH	Alloxan
SMILES	C1(=O)C(=O)NC(=O)NC1=O
Properties
Molecular formula	C4H2N2O4
Molar mass	142.07 g/mol
Melting point	256 °C (decomposition)
Solubility in water	Freely soluble
Hazards
MSDS	MSDS
N(what is this?)  (verify) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Alloxan (2,4,5,6-tetraoxypyrimidine; 2,4,5,6-pyrimidinetetrone) is an oxygenated pyrimidine derivative. It is present as alloxan hydrate in aqueous solution.^[2]

[edit] History

Alloxan was originally isolated in 1818 by Brugnatelli and got its name in 1838 by Friedrich Wöhler and Justus von Liebig. The name "Alloxan" emerged from an amalgamation of the words "Allantoin" and "Oxalsäure" (oxaluric acid).^[3]

[edit] Biological effects

Alloxan is a toxic glucose analogue, which selectively destroys insulin-producing cells in the pancreas when administered to rodents and many other animal species. This causes an insulin-dependent diabetes mellitus (called "Alloxan Diabetes") in these animals, with characteristics similar to type 1 diabetes in humans. Alloxan is selectively toxic to insulin-producing pancreatic beta cells because it preferentially accumulates in beta cells through uptake via the GLUT2 glucose transporter. Alloxan, in the presence of intracellular thiols, generates reactive oxygen species (ROS) in a cyclic reaction with its reduction product, dialuric acid. The beta cell toxic action of alloxan is initiated by free radicals formed in this redox reaction. One study suggests that alloxan does not cause diabetes in humans.^[2] Others show some correlation between alloxan plasma levels and diabetes Type 1 in children. ^[4]

[edit] Synthesis

The original preparation for alloxan was by oxidation of uric acid by nitric acid. Alloxan is a strong oxidizing agent and it forms a hemiacetal with its reduced reaction product dialuric acid (in which a carbonyl group is reduced to a hydroxyl group) which is called alloxantin.^[5]

Alloxan (left) with dialuric acid (right) and alloxantin (center)

[edit] References

1. ^ Merck Index, 11th Edition, 281.
2. ^ ^{a b} Lenzen, S: The mechanisms of alloxan- and streptozotocin-induced diabetes. Diabetologia 51, 216-226, 2008 (Review)
3. ^ Lenzen, S, Panten, U: Alloxan: history and mechanism of action. Diabetologia 31, 337-342, 1988 (Review)
4. ^ A. Mrozikiewicz, D. Kielstrokczewska-Mrozikiewicz, Z. Lstrokowicki, E. Chmara, K. Korzeniowska and P. M. Mrozikiewicz: Blood levels of alloxan in children with insulin-dependent diabetes mellitus. Acta Diabetologica 31, 236-237, 1994 (Review)
5. ^ Alloxantin dihydrate R. Stuart Tipson Organic Syntheses, Coll. Vol. 4, p.25; Vol. 33, p.3 Online article

[edit] External links

• Alloxan and Streptozotocin Diabetes
• Blood levels of alloxan in children with insulin-dependent diabetes mellitus