pyronen.

Brit.

/ˈpʌɪrəʊn/, U.S.

/ˈpaɪˌroʊn/

Origin: Formed within English, by derivation; modelled on a German lexical item. Etymons: pyro- comb. form, -one suffix.

Etymology: < pyro- comb. form + -one suffix, after German Pyron (L. Haitinger & A. Lieben 1885, in Sitzungsberichte der Kaiserlichen Akad. der Wissensch. Wien: Math.-Naturwissensch. Classe: Abtheilung II 91 923).

Chemistry.

Each of two unsaturated, heterocyclic ketones having the formula C₅H₄O₂, spec. γ-pyrone (see note below). Also: a substituted derivative of such a compound. Cf. pyran n.The pyrones are keto derivatives of the pyrans; the commoner isomer, γ-pyrone, is a colourless, basic, crystalline solid, CH=CHOCH=CHCO.

ΘΚΠ

the world > matter > chemistry > organic chemistry > ketones > [noun] > cyclic ketones

pinacone1866

menthone1889

fenchone1891

pyrone1891

tropinone1896

humulone1916

lupulone1919

isoflavone1925

irone1948

tropone1951

1891 Jrnl. Chem. Soc. 60 i. 458 The pyrone is almost insoluble in water or alkalis.

1891 Jrnl. Chem. Soc. 60 ii. 939 The conversion of α-pyrone into pyridine derivatives.

1913 T. H. Pope tr. E. Molinari Treat. Org. Chem. 626 Chelidonic acid,..which is found in celandine, loses CO₂ giving comanic acid and pyrone.

1938 G. H. Richter Textbk. Org. Chem. xxxi. 659 The pyrones are interesting also because the hetero oxygen atom is basic forming oxonium salts with strong acids.

1963 L. F. Fieser & M. Fieser Topics in Org. Chem. ii. 104 Representative natural γ-pyrones are kojic acid, formed by bacterial fermentation of carbohydrates; maltol, isolated from the bark of the larch tree; and yangonin, from the roots of the kava shrub.

1992 Jrnl. Org. Chem. 57 324/1 Pyrones have been formed by analogous condensations and eliminations.

Compounds

pyrone ring n. the six-membered ring present in the pyrones; (also) = pyran ring n. at pyran n. Compounds.

ΚΠ

1905 Jrnl. Amer. Chem. Soc. 27 1311 Meyer attributes the fluorescence of organic compounds in solution to..a so-called ‘fluorophore’ group. In the fluoresceins, for example, it is the pyrone ring.

1962 K. Venkataraman in T. A. Geissman Chem. Flavonoid Compounds iv. 94 Isoflavones undergo hydrolysis with opening of the pyrone ring under mild conditions of alkali treatment.

2004 I. Ramzan & Van Hoan Tran in Y. N. Singh Kava v. 97 Replacement of the methoxy group on the pyrone ring of methysticin with an ethoxy group yielded an active compound that produced mild sedation.

This entry has been updated (OED Third Edition, December 2007; most recently modified version published online March 2022).

单词	pyrone
释义	pyronen. Brit. /ˈpʌɪrəʊn/, U.S. /ˈpaɪˌroʊn/ Origin: Formed within English, by derivation; modelled on a German lexical item. Etymons: pyro- comb. form, -one suffix. Etymology: < pyro- comb. form + -one suffix, after German Pyron (L. Haitinger & A. Lieben 1885, in Sitzungsberichte der Kaiserlichen Akad. der Wissensch. Wien: Math.-Naturwissensch. Classe: Abtheilung II 91 923). Chemistry. Each of two unsaturated, heterocyclic ketones having the formula C₅H₄O₂, spec. γ-pyrone (see note below). Also: a substituted derivative of such a compound. Cf. pyran n.The pyrones are keto derivatives of the pyrans; the commoner isomer, γ-pyrone, is a colourless, basic, crystalline solid, CH=CHOCH=CHCO. ΘΚΠ the world > matter > chemistry > organic chemistry > ketones > [noun] > cyclic ketones pinacone1866 menthone1889 fenchone1891 pyrone1891 tropinone1896 humulone1916 lupulone1919 isoflavone1925 irone1948 tropone1951 1891 Jrnl. Chem. Soc. 60 i. 458 The pyrone is almost insoluble in water or alkalis. 1891 Jrnl. Chem. Soc. 60 ii. 939 The conversion of α-pyrone into pyridine derivatives. 1913 T. H. Pope tr. E. Molinari Treat. Org. Chem. 626 Chelidonic acid,..which is found in celandine, loses CO₂ giving comanic acid and pyrone. 1938 G. H. Richter Textbk. Org. Chem. xxxi. 659 The pyrones are interesting also because the hetero oxygen atom is basic forming oxonium salts with strong acids. 1963 L. F. Fieser & M. Fieser Topics in Org. Chem. ii. 104 Representative natural γ-pyrones are kojic acid, formed by bacterial fermentation of carbohydrates; maltol, isolated from the bark of the larch tree; and yangonin, from the roots of the kava shrub. 1992 Jrnl. Org. Chem. 57 324/1 Pyrones have been formed by analogous condensations and eliminations. Compounds pyrone ring n. the six-membered ring present in the pyrones; (also) = pyran ring n. at pyran n. Compounds. ΚΠ 1905 Jrnl. Amer. Chem. Soc. 27 1311 Meyer attributes the fluorescence of organic compounds in solution to..a so-called ‘fluorophore’ group. In the fluoresceins, for example, it is the pyrone ring. 1962 K. Venkataraman in T. A. Geissman Chem. Flavonoid Compounds iv. 94 Isoflavones undergo hydrolysis with opening of the pyrone ring under mild conditions of alkali treatment. 2004 I. Ramzan & Van Hoan Tran in Y. N. Singh Kava v. 97 Replacement of the methoxy group on the pyrone ring of methysticin with an ethoxy group yielded an active compound that produced mild sedation. This entry has been updated (OED Third Edition, December 2007; most recently modified version published online March 2022). < n.1891
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