2-Hydroxyphenylacetic acid (2-HPAA)

2-Hydroxyphenylacetic acid is a hydroxylated phenolic acid with a structure similar to other phenolic acids. It is an acetic acid in which one methyl hydrogen is replaced by a 2-hydroxyphenyl group. Its synthesis can be achieved by reacting ethylenediamine with sodium hydroxide solution or hydrochloric acid. It is an important intermediate in the metabolism of phenylalanine, tyrosine, and other aromatic amino acids, as well as a key intermediate in the synthesis of other important compounds such as dopamine, serotonin, and melatonin. It is a metabolite of phenylalanine, excreted in the urine of patients with diseases such as phenylketonuria. It has the functions of human metabolites and mouse metabolites. It is a member of phenolic and hydroxy monocarboxylic acids. It is functionally related to acetic acid and phenol.