Phenylalanine

Phenylalanine (symbol Phe or F) is an essential α-amino acid.

Phenylalanine

Skeletal formula of L-phenylalanine
L-Phenylalanine at physiological pH
ball-and-stick model space-filling model
Names
Pronunciation	US: /ˌfɛnəlˈæləniːn/, UK: /ˌfiːnaɪl-/
IUPAC name Phenylalanine
Systematic IUPAC name (S)-2-Amino-3-phenylpropanoic acid
Identifiers
CAS Number	L: 63-91-2 Y D/L: 150-30-1 Y D: 673-06-3 Y
3D model (JSmol)	L: Interactive image L Zwitterion: Interactive image
ChEBI	L: CHEBI:17295 Y D: CHEBI:16998 Y
ChEMBL	L: ChEMBL301523 Y
ChemSpider	L: 5910 Y D/L: 969 Y D: 64639 Y
DrugBank	L: DB00120 Y
ECHA InfoCard	100.000.517
IUPHAR/BPS	L: 3313
KEGG	L: D00021 Y
PubChem CID	L: 6140 D/L: 994 D: 71567
UNII	L: 47E5O17Y3R Y D/L: 8P946UF12S Y D: 032K16VRCU Y
CompTox Dashboard (EPA)	L: DTXSID4040763
SMILES L: c1ccc(cc1)C[C@@H](C(=O)O)N L Zwitterion: [NH3+][C@@H](CC1=CC=CC=C1)C([O-])=O
Properties
Chemical formula	C9H11NO2
Molar mass	165.19 g·mol−1
Acidity (pKa)	1.83 (carboxyl), 9.13 (amino)
Hazards
NFPA 704	1 2 0
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

This essential amino acid is neutral and nonpolar. This is because of the inert and hydrophobic nature of the benzyl side chain.

The L-isomer is used to biochemically form proteins coded for by DNA.

Phenylalanine is a precursor for tyrosine, the monoamine neurotransmitters dopamine, norepinephrine (noradrenaline), epinephrine (adrenaline), and the skin pigment melanin. It is encoded by the codons UUU and UUC.