DECARBOXYLATION

'Decarboxylation' is any chemical reaction in which a carboxyl group (-COOH) is split off from a compound as carbon dioxide (CO₂).

Contents

In biochemistry

In organic chemistry

See also

In biochemistry

Common biosynthetic decarboxylations of amino acids to amines are:

★ tryptophan to tryptamine

★ phenylalanine to phenylethylamine

★ tyrosine to tyramine

★ histidine to histamine

★ serine to ethanolamine

★ glutamic acid to GABA

★ lysine to cadaverine

★ arginine to agmatine

★ ornithine to putrescine

★ 5-HTP to serotonin

★ L-DOPA to dopamine
Other decarboxylation reactions from the citric acid cycle include:

★ pyruvate to acetyl-CoA

★ oxalosuccinate to α-ketoglutarate

★ α-ketoglutarate to succinyl-CoA.
Enzymes that catalyze decarboxylations are called decarboxylases or, more formally, carboxy-lyases (EC number 4.1.1).

In organic chemistry

Chemical decarboxylations reactions often require extensive heating in high-boiling solvents. Copper salts are often added as catalysts. Also the addition of catalytic amounts of cyclohexen-2-one has been reported to catalyze the decarboxylation of amino acids. Decarboxylations are especially easy for beta-keto acids due to the formation of a cyclic transition state for instance in Knoevenagel condensations. The Barton decarboxylation and Hunsdiecker reaction are radical reactions.

See also

★ Oxidative decarboxylation