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

Encouragingly, the research team found no evidence of bacterial resistance to pre-methylenomycin C lactone in Enterococcus under conditions that typically lead to resistance against vancomycin.

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

Solution in dilute alkali was supposed to be accompanied by the rupture of the lactone ring with the formation of the quinonoid salt shown in 2.

From Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 1 "Châtelet" to "Chicago" by Various