| 释义 |
lactone Chem.|ˈlæktəʊn|
[f. L. lact-, lac milk + -one.]
1. (See quot.)
1848Fownes Chem. (ed. 2) 389 Another product of the action of heat on lactic acid, is lactone, a colourless volatile liquid.
2. [ad. G. lacton (R. Fittig 1880, in Ann. d. Chem. CC. 62).] Any of the class of cyclic esters formed (in theory) by the elimination of a molecule of water from a hydroxyl and a carboxyl group of an organic acid, and characterized by the group {b1}O·CO{b1} as part of a ring; freq. with preceding Gr. letter corresponding to the size of the ring (an α-lactone having a three-membered ring, a β-lactone a four-membered one, etc.).
1880Jrnl. Chem. Soc. XXXVIII. 378 Pyroterebic acid..is the internal anhydride of hydroxyisocaproic acid... It is the first representative of its class in the lactic series. For this class of anhydrides the author proposes the name ‘lactones’. 1929Jrnl. Pharmacol. & Exper. Therap. XXXVI. 355 The pharmacological study of a series of lactones with a view to their possible usefulness as anthelmintics pointed towards beta angelica lactone and the dilactone of the diacetone diacetic acid as the most promising. 1936L. J. Desha Org. Chem. xxi. 414 All hydroxy acids lose water when heated..: α-Hydroxy acids yield lactides; β-hydroxy acids are converted into unsaturated acids; γ- and δ-hydroxy acids form lactones. 1971G. A. Taylor Org. Chem. for Students Biol. & Med. xiii. 188 α- and β-hydroxy-acids cannot be converted directly into the corresponding α- and β-lactones (three- and four-membered rings). |