lactone

American  

[lak-tohn] / ˈlæk toʊn /

noun

Chemistry.

1. any of a group of internal esters derived from hydroxy acids.

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lactone British  

/ ˈlæktəʊn, lækˈtɒnɪk /

noun

1. any of a class of organic compounds formed from hydroxy acids and containing the group -C(CO)OC-, where the carbon atoms are part of a ring

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lactone Scientific  

/ lăk′tōn′ /

1. Any of various organic esters derived from organic acids by removal of water. Lactones are formed when the carboxyl (COOH) group of the acid reacts with a hydroxyl (OH) group in the same acid, releasing water and causing the carbon atom to join to the hydroxyl's remaining oxygen atom, forming a ring. Vitamin C, the antibiotic erythromycin, and many commercially important substances are lactones.

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Other Word Forms

• lactonic
  adjective

Etymology

Origin of lactone

First recorded in 1840–50; lact- + -one

Example Sentences

In a recent paper in the Journal of the American Chemical Society, researchers from the Monash Warwick Alliance Combatting Emerging Superbug Threats Initiative reported the discovery of a potent new antibiotic called pre-methylenomycin C lactone.

From Science Daily • Oct. 29, 2025

With its straightforward chemical structure, strong antibacterial power, apparent resistance-proof profile, and scalable production process, pre-methylenomycin C lactone stands out as a promising new candidate.

From Science Daily • Oct. 29, 2025

Acyl-homoserine lactone acylase from Ralstonia strain XJ12B represents a novel and potent class of quorum-quenching enzymes.

From Nature • Nov. 14, 2017

In dogs experimentally infected with two different heartworm isolates taken from suspected lack-of-efficacy cases from the Delta region, the parasites survived repeated treatment with a macrocyclic lactone.

From Nature • Mar. 28, 2017

The cyanhydrin is hydrolysable to an acid, the lactone of which may be reduced by sodium amalgam to a glucoheptose, a non-fermentable sugar containing seven carbon atoms.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 2 "Gloss" to "Gordon, Charles George" by Various