pyrann.

Brit.

/ˈpʌɪran/, U.S.

/ˈpaɪˌræn/

Forms: 1900s– pyran, 1900s– pyrane.

Origin: Formed within English, by derivation. Etymons: pyrone n., -an suffix.

Etymology: < pyr- (in pyrone n.) + -an suffix.With the form pyrane compare -ane suffix².

Chemistry.

Each of two unsaturated, heterocyclic compounds having the formula C₅H₆O, whose molecules have a six-membered ring consisting of five carbon atoms and one oxygen atom with two double bonds between carbon atoms; spec. γ-pyran (see note below). Also: a substituted derivative of such a compound; any compound containing a pyran ring.There are two possible isomeric forms of pyran, differing in the positions of the double bonds. Of these isomers, only one (more fully γ-pyran), CH₂CHCHCHCHO, has been prepared; it is a colourless, unstable oil.Recorded earliest as a formative element in names and in pyran ring n. at Compounds.

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pyran1904

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pyran1904

1901 Jrnl. Chem. Soc. 80 i. 559 7-Hydroxy-2-phenyl-4-methylbenzopyran.]

1904 Jrnl. Chem. Soc. 86 i. 816 (heading) Properties of oxygen in the pyran ring.

1920 Jrnl. Industr. & Engin. Chem. 13 275/2 The number of commercially useful derivatives in which the γ-pyran nucleus is present.

1953 J. S. Fruton & S. Simmonds Gen. Biochem. xvii. 374 The ring in the cyclic form of glucose is related to the heterocyclic compound pyrane.

1965 J. L. Kice & E. N. Marvell Mod. Princ. Org. Chem. xix. 360 Like enol ethers in general these rings are unstable, and α-pyran itself is unknown.

1989 Science 26 May 974/2 Superoxide dismutase, a specific superoxide radical scavenger, which was conjugated with a pyran copolymer.

Compounds

pyran ring n. a ring of five carbon atoms and one oxygen atom.Used to denote both saturated and unsaturated rings of this type.

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the world > matter > chemistry > organic chemistry > hydrocarbons > [noun] > cyclic hydrocarbons > pyran ring

pyran ring1904

1904*Pyran ring [see main sense].

1952 K. Venkataraman Chem. Synthetic Dyes II. xxiv. 742 The γ-pyran ring..occurs in the anthocyanins, the red, violet and blue coloring matters of flowers and fruits.

1983 F. J. McQuillin & M. S. Baird Alicyclic Chem. (ed. 2) ii. 47 The pyran ring is structurally analogous with cyclohexane, and pyran adopts the chair conformation.

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

单词	pyran
释义	pyrann. Brit. /ˈpʌɪran/, U.S. /ˈpaɪˌræn/ Forms: 1900s– pyran, 1900s– pyrane. Origin: Formed within English, by derivation. Etymons: pyrone n., -an suffix. Etymology: < pyr- (in pyrone n.) + -an suffix.With the form pyrane compare -ane suffix². Chemistry. Each of two unsaturated, heterocyclic compounds having the formula C₅H₆O, whose molecules have a six-membered ring consisting of five carbon atoms and one oxygen atom with two double bonds between carbon atoms; spec. γ-pyran (see note below). Also: a substituted derivative of such a compound; any compound containing a pyran ring.There are two possible isomeric forms of pyran, differing in the positions of the double bonds. Of these isomers, only one (more fully γ-pyran), CH₂CHCHCHCHO, has been prepared; it is a colourless, unstable oil.Recorded earliest as a formative element in names and in pyran ring n. at Compounds. ΘΚΠ the world > matter > chemistry > organic chemistry > hydrocarbons > [noun] > cyclic hydrocarbons > derivatives pyran1904 the world > matter > chemistry > organic chemistry > organic compounds > [noun] > heterocyclic compounds > pyrans pyran1904 1901 Jrnl. Chem. Soc. 80 i. 559 7-Hydroxy-2-phenyl-4-methylbenzopyran.] 1904 Jrnl. Chem. Soc. 86 i. 816 (heading) Properties of oxygen in the pyran ring. 1920 Jrnl. Industr. & Engin. Chem. 13 275/2 The number of commercially useful derivatives in which the γ-pyran nucleus is present. 1953 J. S. Fruton & S. Simmonds Gen. Biochem. xvii. 374 The ring in the cyclic form of glucose is related to the heterocyclic compound pyrane. 1965 J. L. Kice & E. N. Marvell Mod. Princ. Org. Chem. xix. 360 Like enol ethers in general these rings are unstable, and α-pyran itself is unknown. 1989 Science 26 May 974/2 Superoxide dismutase, a specific superoxide radical scavenger, which was conjugated with a pyran copolymer. Compounds pyran ring n. a ring of five carbon atoms and one oxygen atom.Used to denote both saturated and unsaturated rings of this type. ΘΚΠ the world > matter > chemistry > organic chemistry > hydrocarbons > [noun] > cyclic hydrocarbons > pyran ring pyran ring1904 1904Pyran ring [see main sense]. 1952 K. Venkataraman Chem. Synthetic Dyes* II. xxiv. 742 The γ-pyran ring..occurs in the anthocyanins, the red, violet and blue coloring matters of flowers and fruits. 1983 F. J. McQuillin & M. S. Baird Alicyclic Chem. (ed. 2) ii. 47 The pyran ring is structurally analogous with cyclohexane, and pyran adopts the chair conformation. This entry has been updated (OED Third Edition, December 2007; most recently modified version published online March 2022). < n.1904
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