Biuret
| |
| |
| |
| Names | |
|---|---|
| Preferred IUPAC name
2-Imidodicarbonic diamide[citation needed] | |
| Systematic IUPAC name
(Carbamoylamino)methanamide[citation needed] | |
Other names
| |
| Identifiers | |
3D model (JSmol)
|
|
| 3DMet | |
| 1703510 | |
| ChEBI | |
| ChemSpider | |
| ECHA InfoCard | 100.003.236 |
| EC Number |
|
| 49702 | |
| KEGG | |
| MeSH | Biuret |
PubChem CID
|
|
CompTox Dashboard (EPA)
|
|
| |
| |
| Properties | |
| C2H5N3O2 | |
| Molar mass | 103.081 g·mol−1 |
| Appearance | White crystals |
| Odor | Odourless |
| Density | 1.467 g/cm3 |
| Melting point | 190 °C (decomposes) |
| Thermochemistry | |
Heat capacity (C)
|
131.3 J K−1 mol−1 |
Std molar
entropy (S⦵298) |
146.1 J K−1 mol−1 |
Std enthalpy of
formation (ΔfH⦵298) |
−565.8–−561.6 kJ mol−1 |
Std enthalpy of
combustion (ΔcH⦵298) |
−940.1–−935.9 kJ mol−1 |
| Hazards | |
| GHS labelling: | |
| |
| Warning | |
| H315, H319, H335 | |
| P261, P305+P351+P338 | |
| Related compounds | |
Related compounds
|
urea, triuret, cyanuric acid |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
| |
Biuret is a chemical compound with the chemical formula C2H5N3O2. It is also known as carbamylurea. It is the result of condensation of two molecules of urea and is an impurity in urea-based fertilizers. This white solid is soluble in hot water. Biuret was first prepared and studied by Gustav Heinrich Wiedemann (1826 - 1899) for his doctoral dissertation, which was submitted in 1847. His findings were reported in several articles.[2][3][4][5]
The term "biuret" also describes a family of organic compounds with the functional group -(HN-CO-)2N-. Thus dimethyl biuret is CH3HN-CO-NR'-CO-NHCH3. A variety of organic derivatives are possible.
Preparation
The parent compound can be prepared by heating urea above the melting point at which temperature ammonia is expelled:[6]
- 2 CO(NH2)2 → H2N-CO-NH-CO-NH2 + NH3
Under related conditions, pyrolysis of urea affords triuret ((H2N-CO-NH)2CO).[6] In general, organic biurets (those with alkyl or aryl groups in place of one or more H atoms) are prepared by trimerization of isocyanates. For example the trimer of 1,6-hexamethylene diisocyanate is also known as HDI-biuret.
Applications
Biuret is also used as a non-protein nitrogen source in ruminant feed,[7] where it is converted into protein by gut microorganisms.[8] It is less favored than urea, due to its higher cost and lower digestibility[9] but this characteristic also slows down its digestion and so decreases the risk of ammonia toxicity.[9][10]
Biuret test
The biuret test is a chemical test for proteins and polypeptides. It is based on the biuret reagent, a blue solution that turns violet upon contact with proteins, or any substance with peptide bonds. The test and reagent do not actually contain biuret; they are so named because both biuret and proteins have the same response to the test.
Related compounds
References
- ^ a b c d e Scifinder, version 2007.1; Chemical Abstracts Service: Columbus, OH; RN 108-19-0 (accessed June 15, 2012)
- ^ Wiedemann, G. (1848). "Ueber ein neues Zersetzungsproduct des Harnstoffs". Annalen der Physik. 150 (5): 67–84. doi:10.1002/andp.18491500508.
{{cite journal}}: Unknown parameter|trans_title=ignored (|trans-title=suggested) (help) - ^ Wiedemann, G. (1847). "Neues Zersetzungsproduct des Harnstoffs". Journal für Praktische Chemie. 42 (3–4): 255–256.
{{cite journal}}: Unknown parameter|trans_title=ignored (|trans-title=suggested) (help) This notice reports that biuret reacts with alkaline copper sulfate to produce a red solution -- the so-called "Biuret test" - ^ Wiedemann, G. (1848). "Ueber eine neue, aus dem Harnstoff entstehende Verbindung". Journal für Praktische Chemie. 43 (5): 271–280.
{{cite journal}}: Unknown parameter|trans_title=ignored (|trans-title=suggested) (help) - ^ Wiedemann, G. (1848). "Biuret. Zersetzungsprodukt des Harnstoffs". Justus Liebig's Annalen der Chemie. 68 (3): 323–326. doi:10.1002/jlac.18480680318.
{{cite journal}}: Unknown parameter|trans_title=ignored (|trans-title=suggested) (help) - ^ a b Meessen, J. H.; Petersen, H. "Urea". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a27_333. ISBN 978-3527306732.
{{cite encyclopedia}}: CS1 maint: multiple names: authors list (link) - ^ Beef cattle feed, Encyclopædia Britannica Online
- ^ Kunkle, B.; Fletcher, J.; Mayo, D. (2013). "Florida Cow-Calf Management, 2nd Edition - Feeding the Cow Herd". IFAS Extension, University of Florida. Publication #AN117.
{{cite web}}: CS1 maint: multiple names: authors list (link) - ^ a b Oltjen, R. R.; Williams, E. E.; Slyter, L. L.; Richardson, G. V. (1969). "Urea versus biuret in a roughage diet for steers". Journal of Animal Science. 29 (5): 816–822. PMID 5391979.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Fonnesbeck, P. V.; Kearl, L. C.; Harris, L. E. (1975). "Feed Grade Biuret as a Protein Replacement for Ruminants. A Review". Journal of Animal Science. 40 (6): 1150–1184.
{{cite journal}}: CS1 maint: multiple names: authors list (link)