3-hydroxybutyric acid

beta-Hydroxybutyric acid

Names
IUPAC name 3-Hydroxybutanoic acid
Identifiers
CAS Number	300-85-6 Y
3D model (JSmol)	Interactive image Interactive image
3DMet	B00239
Beilstein Reference	773861
ChEBI	CHEBI:20067 Y
ChEMBL	ChEMBL1162496 Y
ChemSpider	428 Y
ECHA InfoCard	100.005.546
IUPHAR/BPS	1593
KEGG	C01089
MeSH	beta-Hydroxybutyrate
PubChem CID	441
InChI InChI=1S/C4H8O3/c1-3(5)2-4(6)7/h3,5H,2H2,1H3,(H,6,7) Y Key: WHBMMWSBFZVSSR-UHFFFAOYSA-N Y InChI=1/C4H8O3/c1-3(5)2-4(6)7/h3,5H,2H2,1H3,(H,6,7) Key: WHBMMWSBFZVSSR-UHFFFAOYAO
SMILES O=C(O)CC(O)C CC(CC(=O)O)O
Properties
Chemical formula	C4H8O3
Molar mass	104.11 g·mol−1
Appearance	white solid
Melting point	44-46
Related compounds
Other anions	hydroxybutyrate
Related carboxylic acids	propionic acid lactic acid 3-hydroxypropanoic acid malonic acid hydroxypentanoic acid butyric acid β-methylbutyric acid β-hydroxy β-methylbutyric acid
Related compounds	erythrose threose 1,2-butanediol 1,3-butanediol 2,3-butanediol 1,4-butanediol
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

β-Hydroxybutyric acid, also known as 3-hydroxybutyric acid, is an organic compound and a beta hydroxy acid with the chemical formula CH₃CH(OH)CH₂CO₂H; its conjugate base is β-hydroxybutyrate, also known as 3-hydroxybutyrate. β-Hydroxybutyric acid is a chiral compound with two enantiomers: D-β-hydroxybutyric acid and L-β-hydroxybutyric acid. Its oxidized and polymeric derivatives occur widely in nature.

In humans, D-β-hydroxybutyrate can be synthesized in the liver via the metabolism of fatty acids (e.g., butyrate), β-hydroxy β-methylbutyrate, and ketogenic amino acids through a series of reactions that metabolize these compounds into acetoacetate, which is the first ketone body that is produced in the fasting state. The biosynthesis of D-β-hydroxybutyrate from acetoacetate is catalyzed by the β-hydroxybutyrate dehydrogenase enzyme.

Butyrate can also be metabolized into D-β-hydroxybutyrate via a second metabolic pathway that does not involve acetoacetate as a metabolic intermediate. This metabolic pathway is as follows:

The last reaction in this metabolic pathway, which involves the conversion of D-β-(D-β-hydroxybutyryloxy)-butyrate into D-β-hydroxybutyrate, is catalyzed by the hydroxybutyrate-dimer hydrolase enzyme.