An essential aromatic amino acid that is a precursor of MELANIN; DOPAMINE; noradrenalin (NOREPINEPHRINE), and THYROXINE.

Synonyms: 0, L-Phenylalanine, 47E5O17Y3R, Phenylalanine, Phenylalanine, L Isomer, Phenylalanine, L-Isomer, L-Isomer Phenylalanine, Endorphenyl