Tyrosine
Tyrosine comes from the Greek 'tyros', which means 'cheese'. German chemist Justus von Liebig discovered this amino acid in 1846. Two years later, Warren de la Rue obtained Tyrosine during an investigation on the composition of the cochineal insect. Finally, Emil Erlenmeyer and Lipp first accomplished the synthesis of this amino acid by treating p-aminophenylalanine with nitrous acid. The optical isomers of synthetic Tyrosine were later separated by Emil Fischer by crystallization of the brucine or cinchonine salts of benzoyltyrosine.
Chemical Structure of L-Tyrosine

Identifiers and properties of Tyrosine
IUPAC Name: (2S)-2-Amino-3-(4-hydroxyphenyl)propanoic acid
Symbol: Three-letter code - Tyr. One-letter code - Y
Molecular Weight (Molar Mass): 181.18854 g/mol
Molecular Formula (Structural Formula): C9H11NO3
Canonical SMILES: C1=CC(=CC=C1CC(C(=O)O)N)O
Isomeric SMILES: C1=CC(=CC=C1C[C@@H](C(=O)O)N)O
InChIKey Identifier: OUYCCCASQSFEME-QAXLLPJCDY
CAS Number: 60-18-4
MDL Number: MFCD00002606
Melting point: 290 °C
Solubility in water: 0.45 g/L (25 °C); pKa - 2,20; pKb - 9,11
2D Molfile: Get the molfile
3D PDB file: Get the PDB file
Other names: 3-(4-Hydroxyphenyl)-L-alanine; (S)-alpha-Amino-4-hydroxybenzenepropanoic acid; (-)-alpha-Amino-p-hydroxyhydrocinnamic acid; L-p-Tyrosine; p-Tyrosine; (S)-Tyrosine; L-Beta-(p-Hydroxyphenyl)alanine; (S)-alpha-Amino-4-hydroxybenzenepropanoic acid
What is the role of Tyrosine?
Generally speaking, Tyrosine represents a starting material for neurotransmitters. This amino acid also increases plasma neurotransmitter levels, especially dopamine and noradrenalin, as well as participates in the synthesis of enkephalins providing pain-relieving effects in the body. The aforementioned compounds are very important in terms of brain health, since they are responsible for transmitting nerve impulses and preventing conditions like depression. Besides, dopamine is also essential for the mental functioning and mood, and therefore is widely used to treat mild depression and even stimulate sex drive. According to the numerous studies that were carried out throughout the world, this amino acid proved to be efficient in alleviating stress, anxiety and kept the patients generally more alert.
Tyrosine is known worldwide for supporting and assisting neurotransmitters in the brain. It is particularly important for people experiencing stress, aged, or tired, because in these people, the availability of Tyrosine is depleted. This amino acid, if obtained in full, helps reduce stress, improves mental alertness and mood, and even acts as an appetite suppressant.
Tyrosine is admitted to be essential for the production of a number of important hormones like thyroxin, which plays a key role in regulating metabolism, mental health, skin health, and the human growth rate. Besides, it is known for reducing body fat content, for helping to produce skin and hair pigment and for positively influencing thyroid, pituitary and adrenal gland.