What Is a Glutaric Acid?
Glutaric acid is a type of carboxylic acid whose molecular formula is C5H8O4.
It is also called “pentanedioic acid” or “1,3-propanedicarboxylic acid. Its molecular weight is 132.11 g/mol, its melting point is 95-98 °C, and its CAS number is 110-94-1. Since it is a dicarboxylic acid, it shows relatively strong acidity when dissolved in water.
Uses of Glutaric Acids
Glutaric acid is used in the preparation of solder flux and the manufacture of solder paste because of its high solubility and low residue. It is also useful as a raw material for organic synthesis of polyester polyols and polyamides. Glutaric acid reduces the elasticity of polymers.
In addition, it is used as a pharmaceutical intermediate, initiator of glutaric anhydride, l-ketoglutaric acid, and peroxyglutaric acid, as well as a flavoring agent and pH adjuster.
Properties of Glutaric Acids
1. Physical Properties
Glutaric acid is a white or light yellow crystalline powder. It is well soluble in water and soluble in alcohol, ether, and chloroform.
Glutaric acid is synthesized by the action of sodium cyanide on 1,3-dibromopropane to produce glutaronitrile, which is then hydrolyzed. This reaction utilizes two reactions: first, the SN2 reaction, which is formed by the nucleophilic attack of a cyanide ion on carbon, and then hydrolysis of the cyanide to form a carboxylic acid.
2. Biochemical Properties
Glutaric acid is produced in mammals as an intermediate by catabolism of lysine, hydroxylysine, and tryptophan in an intermediate metabolic process. Deficiency of glutaryl CoA dehydrogenase, which produces glutaric acid in this process, results in a disease called Glutaric Acidemia Type I.
This disease causes severe symptoms such as dystonia, dyskinesia, degeneration of the caudate nucleus and putamen, frontotemporal atrophy, and arachnoid cysts due to the inability to metabolize amino acids normally. The disease is considered incurable, and since the biochemical profile of the disease is elevated urinary glutaric acid and 2-hydroxyglutaric acid concentrations, urinary and plasma glutaric acid is an indicator of glutaric aciduria type 1.
There is also a disorder called Glutaric Aciduria Type 2. This disease is caused by an inherited deficiency of electron transfer flavin protein (ETF) and ETF dehydrogenase (ETFDH) in the mitochondria, which supply electrons to the electron transfer system resulting from multiple dehydrogenase reactions within the mitochondria, including the beta-oxidation pathway. When these enzymes are deficient, metabolism fails. As a result, many cases of ETFDH in newborns present with severe cardiomyopathy, heart failure, and nonketotic hypoglycemia beginning shortly after birth.
Other Information on Glutaric Acids
1. Glutamic Acid Derivatives in the Body
Glutaric acid is obtained by replacing one hydrogen atom on the second carbon of glutaric acid with an amino group. The carbonyl group attached to the carbon at position 2 of glutaric acid is called α-ketoglutaric acid.
α-Ketoglutaric acid is a substance that plays an important role as an intermediate in the citric acid circuit, one of the metabolic pathways in mammals. The metabolic pathway of amino acids such as glutamic acid also passes through α-ketoglutaric acid as an intermediate.
2. Industrially Used Glutaric Acid Derivatives
Glutaric aldehyde, which is produced by treating glutaric acid with a reducing agent, is a substance often used industrially. Imports in Japan in 2007 amounted to less than 100-1,000 tons/year.
Major uses include tanning agents for hides, fixing agents for paper and rastik, disinfectants for endoscopes and surgical instruments, algaecides for cooling towers, disinfectants for poultry houses and equipment, and developers for radiographs.