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单词 ketone
释义 ketone Chem.|ˈkiːtəʊn|
[a. Ger. keton (pl. ketone), a modification of acetone, introduced by Gmelin, Handbuch d. Chem. (ed. 4, 1848) IV. 40, 187.]
1. The name of a class of chemical compounds formed by oxidation of the secondary alcohols or carbinols, to which they stand in some respects in the relation of aldehydes. The lowest of the series, dimethyl ketone, is common acetone.
‘The ketones, in their simplest form, contain a carbonyl group CO attached to two monad hydrocarbon radicles. If the two radicles are identical as in acetone, the compound is a simple ketone; if different, as in methyl-ethyl-ketone CH3·CO·CH2·CH3, it is a mixed ketone. Compounds containing two carbonyl groups are termed diketones; those containing three triketones’ (Morley & Muir Watts' Dict. Chem. III. 102/2).
1851Brazier & Gossleth in Q. Jrnl. Chem. Soc. III. 215 A new class of bodies known under the name of acetones or ketones.Ibid. In preparing the ketone of caproic acid.1852Watts tr. Gmelin's Handbk. Chem. VII. 214 (heading) Acetones in general or Ketones. All ketones are highly combustible.1872Dict. Chem. VI. 764 A peculiar penetrating smell, which deserves to be called the ketone-smell.1873Fownes' Chem. (ed. 11) 595 The formation of a ketone by oxidation is the essential characteristic of a secondary alcohol.1897Allbutt's Syst. Med. III. 200 Glucose (C6H12O6) now regarded as a ketone of a hexatomic alcohol.
2. Special combs.: ketone body, any of the three related compounds acetone, acetoacetic acid, and β-hydroxybutyric acid, which are produced in the body in fatty- and amino-acid metabolism; an ‘acetone body’.
1915Arch. Internal Med. XV. 40 There are in the literature only casual references to the influence of organotherapy on the formation and excretion of ketone bodies.1936Jrnl. Nutrition XII. 647 The term ‘rate of ketogenesis’{ddd}takes into account both the ketonemia, or level of ketone bodies in the blood, and the ketonuria, or the rate of ketone body excretion in the urine.1959A. White et al. Princ. Biochem. (ed. 2) xix. 479 The total ketone body concentration in blood, expressed as β-hydroxybutyrate, is normally below 1 mg. per 100 ml., and the average total daily excretion in the urine is approximately 20 mg.1974Nature 18 Jan. 161/2 Urine samples were tested for ‘ketone bodies’ with a commercial preparation that contains sodium nitroprusside.
Hence keˈtonic a., of or pertaining to ketones, as in ketonic acid, a compound containing the radical carbonyl, CO, and having the characteristic properties of both a ketone and an acid. So ˈketol, a ketonic alcohol; ˈketose, a sugar which is a ketonic alcohol, e.g. lævulose, or fruit sugar.
1876Jrnl. Chem. Soc. XXIX. 926 The ketonic acids are converted by nascent hydrogen into oxy-acids.1891Ibid. LX. 1176 Ketoses.1892Morley & Muir Watts Dict. Chem. III. 103/1 Certain ketonic acids part with carbon dioxide, forming ketones.1892E. F. Smith tr. V. von Richter's Chem. Carbon Compounds (ed. 2) 498 Bromine water..oxidises the aldoses to their corresponding monocarboxylic acids..whereas the ketoses (fructose and sorbinose) are not attacked.1894G. McGowan tr. Bernthsen's Text-bk. Org. Chem. (ed. 2) 237 (heading) Ketone-alcohols (ketols).1899M'Gowan tr. Beruthsen's Organ. Chem. 245 These alkylated aceto-acetic ethers..undergo either the ‘ketonic decomposition’ or the ‘acid decomposition’.1938M. L. Wolfram in H. Gilman Org. Chem. I. xvi. 1442 The Lobry de Bruyn dilute alkali interconversion reaction was used..in obtaining the crystalline ketose of lactose (lactulose).1968R. O. C. Norman Princ. Org. Synthesis xvi. 501 Treatment [of an epoxide] with dimethyl sulphoxide gives an α-ketol.1972New Phytologist LXXI. 475 The phenomenon of ketose formation in polyol media is much better documented for bacteria where, for example, fructose may be formed from mannitol in yields of up to..95%.
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