Mesoxalic acid

Mesoxalic acid

Names
IUPAC name oxopropanedioic acid
Other names Ketomalonic acid Oxomalonic acid Alpha-ketomalonic acid 2-Oxopropanedioic acid
Identifiers
CAS Number	473-90-5 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:30842 Y
ChemSpider	9727 Y
DrugBank	DB03589 Y
ECHA InfoCard	100.006.796
KEGG	C00830 Y
PubChem CID	10132
InChI InChI=1S/C3H2O5/c4-1(2(5)6)3(7)8/h(H,5,6)(H,7,8) Y Key: XEEVLJKYYUVTRC-UHFFFAOYSA-N Y InChI=1/C3H2O5/c4-1(2(5)6)3(7)8/h(H,5,6)(H,7,8) Key: XEEVLJKYYUVTRC-UHFFFAOYAW
SMILES O=C(O)C(=O)C(=O)O
Properties
Chemical formula	C3H2O5
Molar mass	118.045 g/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

Mesoxalic acid, also called oxomalonic acid or ketomalonic acid, is an organic compound with formula C₃H₂O₅ or HO-(C=O)₃-OH.

Mesoxalic acid is both a dicarboxylic acid and a ketonic acid. It readily loses two protons to yield the divalent anion C₃O₅²⁻, called mesoxalate, oxomalonate, or ketomalonate. These terms are also used for salts containing this anion, such as sodium mesoxalate, Na₂C₃O₅; and for esters containing the -C₃O₅- or -O-(C=O)₃-O- moiety, such as diethyl mesoxalate, (C₂H₅)₂C₃O₅. Mesoxalate is one of the oxocarbon anions, which (like carbonate CO₃²⁻ and oxalate C₂O₄²⁻) consist solely of carbon and oxygen.

Mesoxalic acid readily absorbs and reacts with water to form a product commonly called "mesoxalic acid (mono)hydrate", more properly dihydroxymalonic acid, HO-(C=O)-C(OH)₂-(C=O)-OH. In product catalogs and other contexts, the terms "mesoxalic acid", "oxomalonic acid", etc. often refer to this "hydrated" compound. In particular, the product traded as "sodium mesoxalate monohydrate" is almost always sodium dihydroxymalonate.