Valine

Valine

Names
IUPAC name Valine
Other names 2-amino-3-methylbutanoic acid
Identifiers
CAS Number	516-06-3 Y 72-18-4 (L-isomer) Y 640-68-6 (D-isomer) Y
3D model (Jmol)	Interactive image
ChEBI	CHEBI:57762 Y
ChEMBL	ChEMBL43068 Y
ChemSpider	6050 Y
DrugBank	DB00161 Y
ECHA InfoCard	100.000.703
EC Number	208-220-0
IUPHAR/BPS	4794
KEGG	D00039 Y
PubChem	1182
UNII	4CA13A832H Y
InChI InChI=1S/C5H11NO2/c1-3(2)4(6)5(7)8/h3-4H,6H2,1-2H3,(H,7,8)/t4-/m0/s1 Y Key: KZSNJWFQEVHDMF-BYPYZUCNSA-N Y InChI=1/C5H11NO2/c1-3(2)4(6)5(7)8/h3-4H,6H2,1-2H3,(H,7,8)/t4-/m0/s1 Key: KZSNJWFQEVHDMF-BYPYZUCNBW
SMILES CC(C)[C@@H](C(=O)O)N
Properties
Chemical formula	C5H11NO2
Molar mass	117.15 g·mol−1
Density	1.316 g/cm3
Melting point	298 °C (568 °F; 571 K) (decomposition)
Solubility in water	soluble
Acidity (pKa)	2.32 (carboxyl), 9.62 (amino)
Magnetic susceptibility (χ)	-74.3·10−6 cm3/mol
Supplementary data page
Structure and properties	Refractive index (n), Dielectric constant (εr), etc.
Thermodynamic data	Phase behaviour solid–liquid–gas
Spectral data	UV, IR, NMR, MS
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

Valine (abbreviated as Val or V) encoded by the codons GUU, GUC, GUA, and GUG is an α-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated −NH₃⁺ form under biological conditions), an α-carboxylic acid group (which is in the deprotonated −COO⁻ form under biological conditions), and a side chain isopropyl variable group, classifying it as a non-polar amino acid. It is essential in humans, meaning the body cannot synthesize it and thus it must be obtained from the diet. Human dietary sources are any proteinaceous foods such as meats, dairy products, soy products, beans and legumes.

Along with leucine and isoleucine, valine is a branched-chain amino acid. In sickle-cell disease, valine substitutes for the hydrophilic amino acid glutamic acid in β-globin. Because valine is hydrophobic, the hemoglobin is prone to abnormal aggregation.

Valine was first isolated from casein in 1901 by Hermann Emil Fischer. The name valine comes from valeric acid, which in turn is named after the plant valerian due to the presence of the acid in the roots of the plant.

According to IUPAC, carbon atoms forming valine are numbered sequentially starting from 1 denoting the carboxyl carbon, whereas 4 and 4' denote the two terminal methyl carbons.