Oxaloacetic acid

Oxaloacetic acid
Names


IUPAC name Oxobutanedioic acid
Other names Oxaloacetic acid Oxalacetic acid 2-Oxosuccinic acid Ketosuccinic acid
Identifiers
CAS Number	328-42-7^Y
3D model (Jmol)	Interactive image
ChEBI	CHEBI:30744^Y
ChemSpider	945^Y
ECHA InfoCard	100.005.755
EC Number	206-329-8
IUPHAR/BPS	5236
PubChem CID	970
InChI InChI=1S/C4H4O5/c5-2(4(8)9)1-3(6)7/h1H2,(H,6,7)(H,8,9)^Y Key: KHPXUQMNIQBQEV-UHFFFAOYSA-N^Y
SMILES O=C(O)C(=O)CC(=O)O
Properties
Chemical formula	C₄H₄O₅
Molar mass	132.07 g/mol
Density	0,18 g/cm³
Melting point	161 °C (322 °F; 434 K)
Thermochemistry
Std enthalpy of formation (Δ_fH^o₂₉₈)	-943.21 kJ/mol
Std enthalpy of combustion (Δ_cH^o₂₉₈)	-1205.58 kJ/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y (what is ^YN ?)
Infobox references

Oxaloacetic acid (also known as oxalacetic acid) is a crystalline organic compound with the chemical formula HO₂CC(O)CH₂CO₂H. Oxaloacetic acid, in the form of its conjugate base oxaloacetate, is a metabolic intermediate in many processes that occur in animals. It takes part in the gluconeogenesis, urea cycle, glyoxylate cycle, amino acid synthesis, fatty acid synthesis and citric acid cycle.

Oxaloacetic acid undergoes successive deprotonations to give the dianion:

At high pH, the enolizable proton is ionized:

The enol forms of oxaloacetic acid are particularly stable, so much so that the two tautomer have different melting points (152 °C for the cis isoform and 184 °C for the trans isoform).

Oxaloacetate forms in several ways in nature. A principal route is upon oxidation of L-malate, catalysed by malate dehydrogenase, in the citric acid cycle. Malate is also oxidized by succinate dehydrogenase in a slow reaction with the initial product being enol-oxaloacetate.
It also arises from the condensation of pyruvate with carbonic acid, driven by the hydrolysis of ATP:

Occurring in the mesophyll of plants, this process proceeds via phosphoenolpyruvate, catalysed by pyruvate carboxylase.
Oxaloacetate can also arise from trans- or de- amination of aspartic acid.

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Wikipedia