Sebacic acid is a naturally occurring

dicarboxylic acid In organic chemistry, a dicarboxylic acid is an organic compound containing two carboxyl groups (). The general molecular formula for dicarboxylic acids can be written as , where R can be aliphatic or aromatic.Boy Cornils, Peter Lappe "Dicarbox ...

with the chemical formula . It is a white flake or powdered solid. ''Sebaceus'' is Latin for tallow candle, ''sebum'' is Latin for tallow, and refers to its use in the manufacture of candles. Sebacic acid is a derivative of

castor oil Castor oil is a vegetable oil pressed from castor beans, the seeds of the plant ''Ricinus communis''. The seeds are 40 to 60 percent oil. It is a colourless or pale yellow liquid with a distinct taste and odor. Its boiling point is and its den ...

. In the industrial setting, sebacic acid and its homologues such as

azelaic acid Azelaic acid (AzA), or nonanedioic acid, is an organic compound with the formula HOOC(CH2)7carboxylic acid, COOH. This saturated dicarboxylic acid exists as a white powder. It is found in wheat, rye, and barley. It is a precursor to diverse ind ...

can be used as a monomer for

nylon Nylon is a family of synthetic polymers characterised by amide linkages, typically connecting aliphatic or Polyamide#Classification, semi-aromatic groups. Nylons are generally brownish in color and can possess a soft texture, with some varieti ...

610, plasticizers, lubricants,

hydraulic fluid A hydraulic fluid or hydraulic liquid is the medium by which power is transferred in hydraulic machinery. Common hydraulic fluids are based on mineral oil or water. Examples of equipment that might use hydraulic fluids are excavators and backho ...

s, cosmetics, candles, etc. It can be used as a surfactant in the lubricating oil industry to increase the antirust properties of lubricating oils on metals.

Production and reactions

Sebacic acid is produced from

by cleavage of

ricinoleic acid Ricinoleic acid, formally called 12-hydroxy-9-''cis''-octadecenoic acid, is a fatty acid. It is an Unsaturated fatty acid, unsaturated omega-9 fatty acid and a hydroxy acid. It is a major component of the seed oil obtained from the seeds of casto ...

, which is obtained from castor oil. Octanol and

glycerin Glycerol () is a simple triol compound. It is a colorless, odorless, sweet-tasting, viscous liquid. The glycerol backbone is found in lipids known as glycerides. It is also widely used as a sweetener in the food industry and as a humectant in pha ...

are byproducts. It can also be obtained from decalin via the a

hydroperoxide Hydroperoxides or peroxols are Chemical compound, compounds of the form ROOH, where R stands for any group, typically Organic compound, organic, which contain the hydroperoxy functional group (). Hydroperoxide also refers to the hydroperoxide anio ...

, which rearranges to give a hydroxycyclodecanone, which dehydrates to give cyclodecenone, a precursor to sebacic acid. Sebacic acid has also been produced commercially by Kolbe electrolysis of

adipic acid Adipic acid or hexanedioic acid is the organic compound with the formula C6H10O4. It a white crystalline powder at standard temperature and pressure. From an industrial perspective, it is the most important dicarboxylic acid at about 2.5 billion ...

Potential medical significance

Sebum is a secretion by skin

sebaceous gland A sebaceous gland or oil gland is a microscopic exocrine gland in the skin that opens into a hair follicle to secrete an oily or waxy matter, called sebum, which lubricates the hair and skin of mammals. In humans, sebaceous glands occur in ...

s. It is a waxy set of

lipids Lipids are a broad group of organic compounds which include fats, waxes, sterols, fat-soluble vitamins (such as vitamins Vitamin A, A, Vitamin D, D, Vitamin E, E and Vitamin K, K), monoglycerides, diglycerides, phospholipids, and others. The fu ...

composed of

triglycerides A triglyceride (from ''wikt:tri-#Prefix, tri-'' and ''glyceride''; also TG, triacylglycerol, TAG, or triacylglyceride) is an ester derived from glycerol and three fatty acids. Triglycerides are the main constituents of body fat in humans and oth ...

(≈41%), wax esters (≈26%),

squalene Squalene is an organic compound. It is a triterpene with the formula C30H50. It is a colourless oil, although impure samples appear yellow. It was originally obtained from shark liver oil (hence its name, as '' Squalus'' is a genus of sharks). ...

(≈12%), and free fatty acids (≈16%). Included in the free fatty acid secretions in sebum are

polyunsaturated fatty acid In biochemistry and nutrition, a polyunsaturated fat is a fat that contains a polyunsaturated fatty acid (abbreviated PUFA), which is a subclass of fatty acid characterized by a backbone with two or more carbon–carbon double bonds. Some polyunsa ...

s and sebacic acid. Sebacic acid is also found in other lipids that coat the skin surface. Human neutrophils can convert sebacic acid to its 5-oxo analog, i.e., , a

structural analog A structural analog, also known as a chemical analog or simply an analog, is a chemical compound, compound having a chemical structure, structure similar to that of another compound, but differing from it in respect to a certain component. It can ...

of 5-oxo-eicosatetraenoic acid and like this oxo-eicosatetraenoic acid is an exceptionally potent activator of eosinophils,

monocytes Monocytes are a type of leukocyte or white blood cell. They are the largest type of leukocyte in blood and can differentiate into macrophages and monocyte-derived dendritic cells. As a part of the vertebrate innate immune system monocytes also i ...

, and other pro-inflammatory cells from humans and other species. This action is mediated by the OXER1 receptor on these cells. It is suggested that sebacic acid is converted to its 5-oxo analog during, and thereby stimulates pro-inflammatory cells to contribute to the worsening of, various inflammatory skin conditions.

References

{{Authority control Dicarboxylic acids