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单词 pyrrole
释义 pyrrole Chem.|ˈpɪrəʊl|
Also -ol, pyrrhol.
[f. Gr. πυρρός reddish + L. oleum oil.]
a. A feebly basic, colourless transparent liquid, C4H5N, contained in bone-oil and coal-tar, having an odour like chloroform. Also, any derivative of this containing a pyrrole ring.
1835F. F. Runge in R. D. & T. Thomson's Rec. Gen. Sc. I. 48 Pyrrol (red oil) in a pure state is a gaseous body possessing the odour of turnips.1842E. Turner's Elem. Chem. (ed. 7) 1180 Runge has described under the names of carbolic acid,..pyrrole, and cyanol,..compounds derived from coal tar.1902Jrnl. Chem. Soc. LXXXII. i. 54 Better yields of pyrroline are obtained by reducing pyrroles with zinc and hydrochloric acid than by using zinc and acetic acid.1926H. G. Rule tr. J. Schmidt's Text-bk. Org. Chem. 521 Pyrroles are aromatic in character and possess points in common with both phenols and aromatic amines.1954New Biol. XVI. 33 The tendency of the related pyrroles to combine with metal atoms to form highly coloured reactive compounds, such as hydrogenase and cytochrome, and probably later chlorophyll and haemin, points the way to the evolution of enzyme systems and photosynthesis.1972J. M. Tedder et al. Basic Org. Chem. IV. ix. 454 On reduction with hydriodic acid haem yields eight comparatively simple pyrroles.
b. attrib. and Comb., as pyrrole base, any of a series of bases containing a pyrrole ring; pyrrole nucleus, ring, a doubly unsaturated ring of four carbon atoms and one nitrogen atom; pyrrole red: see quot. 1877.
1851T. Anderson in Trans. Roy. Soc. Edin. (1853) XX. 249 A series of bases..which I designate provisionally by the name of pyrrol bases.1875Watts Dict. Chem. VII. 1035 Pyrrol-bases appear to be present, together with bases of the pyridine series, in tobacco-smoke.1877Fownes' Chem. II. 375 By heating an acid solution of pyrrol, a red, flaky substance, pyrrol-red, is produced, containing C12H14N2O.1913Bloxam & Lewis Bloxam's Chem. (ed. 10) 782 The metals are not present as bases, but as integral parts of the complex molecules, probably exercising their subsidiary valencies, and uniting a number of pyrrol nuclei.1926H. G. Rule tr. J. Schmidt's Text-bk. Org. Chem. 523 This oxidation has recently been recognised as a valuable means of determining the orientation of substituents in the pyrrole nucleus, and also for detecting the presence of a pyrrole ring in substances of unknown constitution.1970R. W. McGilvery Biochem. xxi. 494 The basic unit of porphyrins is the pyrrole ring, with four of these linked to form the large porphyrin ring.
Hence pyˈrrolic a.
1909in Cent. Dict. Suppl.1912Chem. Abstr. VI. 2749 Pyrrolic α-, β- and γ-diketones.1955Endeavour July 135/2 (caption) Porphobilinogen, the simplest pyrrolic substance known to be a precursor of haem and porphyrins.1972J. M. Tedder et al. Basic Org. Chem. IV. ix. 464 The blood-red, tripyrrole microbial pigment, prodigiosin, provides an example of the biogenesis of pyrrolic compounds.
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