4-Hydroxyphenylacetaldehyde, also known as ''p''-hydroxyphenylacetaldehyde, is a

natural product A natural product is a natural compound or substance produced by a living organism—that is, found in nature. In the broadest sense, natural products include any substance produced by life. Natural products can also be prepared by chemical s ...

with the formula HOC₆H₄CH₂CHO. It is a derivative of

phenylacetaldehyde Phenylacetaldehyde is an organic compound used in the synthesis of fragrances and polymers. Phenylacetaldehyde is an aldehyde that consists of acetaldehyde bearing a phenyl substituent; the parent member of the phenylacetaldehyde class of compound ...

and occurs as a white solid at room temperature.

Synthesis

4-Hydroxyphenylacetaldehyde can be synthesized from (

L-tyrosine -Tyrosine or tyrosine (symbol Tyr or Y) or 4-hydroxyphenylalanine is one of the 20 standard amino acids that are used by cells to synthesize proteins. It is a conditionally essential amino acid with a polar side group. The word "tyrosine" is ...

) via a parsley

tyrosine -Tyrosine or tyrosine (symbol Tyr or Y) or 4-hydroxyphenylalanine is one of the 20 standard amino acids that are used by cells to synthesize proteins. It is a conditionally essential amino acid with a polar side group. The word "tyrosine" is ...

decarboxylase Carboxy-lyases, also known as decarboxylases, are carbon–carbon lyases that add or remove a carboxyl group from organic compounds. These enzymes catalyze the decarboxylation of amino acids and alpha-keto acids. Classification and nomenclature ...

Occurrence

4-Hydroxyphenylacetaldehyde is produced from the

metabolism Metabolism (, from ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the co ...

tyramine Tyramine ( ) (also spelled tyramin), also known under several other names, is a naturally occurring trace amine derived from the amino acid tyrosine. Tyramine acts as a catecholamine releasing agent. Notably, it is unable to cross the bl ...

monoamine oxidase Monoamine oxidases (MAO) () are a family of enzymes that catalyze the oxidation of monoamines, employing oxygen to clip off their amine group. They are found bound to the outer membrane of mitochondria in most cell types of the body. The fi ...

(MAO)

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

s in humans and the tyramine oxidase (tynA) enzyme in ''

Escherichia coli ''Escherichia coli'' ( )Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. is a gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus '' Escherichia'' that is commonly fo ...

''. In both species, it is subsequently metabolized into 4-hydroxyphenylacetate by

aldehyde dehydrogenase Aldehyde dehydrogenases () are a group of enzymes that catalyse the oxidation of aldehydes. They convert aldehydes (R–C(=O)) to carboxylic acids (R–C(=O)). The oxygen comes from a water molecule. To date, nineteen ALDH genes have ...

(ALDH) enzymes in humans and the

phenylacetaldehyde dehydrogenase In enzymology, a phenylacetaldehyde dehydrogenase () is an enzyme that catalyzes the chemical reaction :phenylacetaldehyde + NAD+ + H2O \rightleftharpoons phenylacetate + NADH + 2 H+ The 3 substrates of this enzyme are phenylacetaldehyde, NAD+, ...

(feaB) enzyme in ''E. coli''. The condensation of 4-hydroxyphenylacetaldehyde and

dopamine Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic chemical of the catecholamine and phenethylamine families. It is an amine synthesized ...

is a key step in the biosynthesis of

benzylisoquinoline alkaloids The benzylisoquinoline alkaloids are natural products that can be classified as isoquinoline alkaloids and are derived from benzylisoquinoline. They also include the benzyl(tetrahydro)isoquinoline alkaloids. Occurrence Benzylisoquinoline alkal ...

. These natural products include

berberine Berberine is a Quaternary ammonium cation, quaternary ammonium salt from the protoberberine group of benzylisoquinoline alkaloids, occurring naturally as a secondary metabolite in some plants including species of ''Berberis'', from which its name ...

and

morphine Morphine, formerly also called morphia, is an opiate that is found naturally in opium, a dark brown resin produced by drying the latex of opium poppies (''Papaver somniferum''). It is mainly used as an analgesic (pain medication). There are ...

References

{{DEFAULTSORT:Hydroxyphenylacetaldehyde, 4- 4-Hydroxyphenyl compounds Aldehydes Phenolic human metabolites