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  • Chemistry  (18)
  • Rose pigments  (1)
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  • 11
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Carotenoids from Hips of Rosa pomifera: Discovery of (5Z)-Neurosporene; Synthesis of (3R, 15Z)-RubixanthinExtensive chromatographic separations of the mixture of carotenoids from ripe hips of R. pomifera have led to the identification of 43 individual compounds, namely (Scheme 2): (15 Z)-phytoene (1), (15 Z)-phytofluene (2), all-(E)-phytofluene (2a), ξ-carotene (3), two mono-(Z)-ξ-carotenes (3a and 3b), (6 R)-∊, ψ-carotene (4), a mono-(Z)-∊, ψ-carotene (4a), β, ψ-carotene (5), a mono-(Z)-β, ψ-carotene (5a), neurosporene (6), (5 Z)-neurosporene (6a), a mono-(Z)-neurosporene (6b), lycopene (7), five (Z)-lycopenes (7a-7e), β, β-carotene (8), two mono-(Z)-β, β-carotenes (probably (9 Z)-β, β-carotene (8a) and (13 Z)-β, β-carotene (8b)), β-cryptoxanthin (9), three (Z)-β-cryptoxanthins (9a-9c), rubixanthin (10), (5′ Z)-rubixanthin (=gazaniaxanthin; 10a), (9′ Z)-rubixanthin (10b), (13′ Z)- and (13 Z)-rubixanthin (10c and 10d, resp.), (5′ Z, 13′ Z)- or (5′ Z, 13 Z)-rubixanthin (10e), lutein (11), zeaxanthin (12), (13 Z)-zeaxanthin (12b), a mono-(Z)-zeaxanthin (probably (9 Z)-zeaxanthin (12a)), (8 R)-mutatoxanthin (13), (8 S)-mutatoxanthin (14), neoxanthin (15), (8′ R)-neochrome (16), (8′ S)-neochrome (17), a tetrahydroxycarotenoid (18?), a tetrahydroxy-epoxy-carotenoid (19?), and a trihydroxycarotenoid of unknown structure.Rubixanthin (10) and (5′ Z)-rubixanthin (10a) can easily be distinguished by HPLC. separation and CD. spectra at low temperature. The synthesis of (3 R, 15 Z)-rubixanthin (29) is described.The isolation of (5 Z)-neurosporene (6a) supports the hypothesis that the ∊-end group arises by enzymatic cyclization of precursors having a (5 Z)- or (5′ Z)-configuration.
    Additional Material: 9 Ill.
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  • 12
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Diastereoisomeric Mutatochromes: Separation, Absolute Configuration, and Spectra and Chromatographic Behaviour(5S, 6R)-5, 6-Epoxy-5, 6-dihydro-β, β-carotent (2), prepared from azafrinal (1) was rearranged in an acid-catalyzed reaction into the mixture of (5S, 8S)- and (5S, 8 R)-5, 8-epox-5, 8-dihydro-β, β-carotenes = ‘mutatochrome’. HPLC separation of the individual diastereoisomers led to the pure isomers for the first time. Their structures were assigned by analysis of the characteristic pattern of the signals of H—C(7) and H—C(8), respectively, in 1H-NMR spectra. Although many reports of the occurrence of ‘mutatochrome’ exist, it is as yet not clear whether optically active or racemic forms predominate in nature. Combination of HPLC separations with UV/VIS and CD spectra should now allow an unambigous identification of the isomer in question.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 13
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 10′-Apolycopen-10′-ol and 10′-Apolycopen-10′-oic Acid from the Petals of the Rose Hybrid ‘Maréchal Niel’The novel 10′-apolycopen-10′-ol (1) and 10′-apolycopen-10′-oic acid (4) were isolated from the yellow petals of the once world-renowned rose hybrid ‘Maréchal Niel’. The relative amount of either 1 or 4 produced by the plant depends upon the climatic conditions. Both 1 and 4 together with related compounds were synthetisized and characterized by spectral data.
    Additional Material: 1 Ill.
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  • 14
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 71 (1988), S. 1689-1696 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: (all-E)-12′-Apozeanthinol, Persicaxanthine, and PersicachromesReexamination of the so-called ‘persicaxanthins’ and ‘persicachromes’, the fluorescent and polar C25-apocarotenols from the flesh of cling peaches, led to the identification of the following components: (3R)-12′-apo-β-carotene-3,12′-diol (3), (3S,5R,8R, all-E)- and (3S,5R,8S,all-E)-5,8-epoxy-5,8-dihydro-12′-apo-β-carotene-3,12′-diols (4 and 5, resp.), (3S,5R,6S,all-E)-5,6-epoxy-5,6-dihydro-l2′-apo-β-carotene-3,12′-diol =persicaxanthin; (6), (3S,5R,6S,9Z,13′Z)-5,6-dihydro-12′apo-β-carotene-3,12′-diol (7; probable structure), (3S,5R,6S,15Z)-5,6-epoxy-5,6-dihydro-12′-apo-β-carotene-3,12′-diol (8), and (3S,5R,6S,13Z)-5,6-epoxy-5,6-dihydro-12′-apo-β-carotene-3,12′-diol (9). The (Z)-isomers 7-9 are very labile and, after HPLC separation, isomerized predominantly to the (all-E)-isomer 6.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 15
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Absolute Configuration of Antheraxanthin, ‘cis-Aritheraxanthin’ and of the Stereoisomeric MutatdxanthinsThe assignement of structure 2 to antheraxanthin (all-E)-(3 S, 5 R, 6 S, 3′ R)-5,6-epoxy-5,6-dihydro-β,β-carotene-3,3′-diol and of 1 to ‘cis-antheraxanthin’ (9Z)-(3 S, 5 R, 6 S, 3′ R)-5,6-epoxy-5,6-dihydro-β,β-carotene-3,3′-diol is based on chemical correlation with (3 R, 3′ R)-zeaxanthin and extensive 1H-NMR. measurements at 400 MHz. ‘Semisynthetic antheraxanthin’ ( = ‘antheraxanthin B’) has structure 6. For the first time the so-called ‘mutatoxanthin’, a known rearrangement product of either 1 or 2, has been separated into pure and crystalline C(8)-epimers (epimer A of m.p. 213° and epimer B of m.p. 159°). Their structures were assigned by spectroscopical and chiroptical correlations with flavoxanthin and chrysanthemaxanthin. Epimer A is (3 S, 5 R, 8 S, 3′ R)-5,8-epoxy-5,8-dihydro-β,β-carotene-3,3′-diol (4; = (8 S)mutatoxanthin) and epimer B is (3 S, 5 R, 8 R, 3′ R)-5,8-epoxy-5,8-dihydro-β,β-carotene-3,3′-diol (3; = (8 R)-mutatoxanthin). The carotenoids 1-4 have a widespread occurrence in plants. We also describe their separation by HPLC. techniques. CD. spectra measured at room temperature and at - 180° are presented for 1-4 and 6. Antheraxanthin (2) and (9Z)-antheraxanthin (1) exhibit a typical conservative CD. The CD. Spectra also allow an easy differentiation of 6 from its epimer 2. The isomeric (9Z)-antheraxanthin (1) shows the expected inversion of the CD. curve in the UV. range. The CD. spectra of the epimeric mutatoxanthins 3 and 4 (β end group) are dissimilar to those of flavoxanthin/chrysanthemaxanthin (ε end group). They allow an easy differentiation of the C (8)-epimers.
    Additional Material: 10 Ill.
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  • 16
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 73 (1990), S. 468-475 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Structure of the Valenciaxanthins and ValenciachromesValenciaxanthin, a carotenoid first isolated from Californian Valencia orange juice in 1952/1954 by American scientists, was re-isolated from fresh Spanish ‘Navelinas’ and shown, by spectroscopical and chiroptical examination, to have the unexpected (9Z)-10′-apo-11′,12′-dihydroviolaxantin-10′-ol structure 6. A further, very minor component represents the (all-E)-structure 7. Therefore, the Valenciachromes are the furanoid rearrangement products of 6 and 7 and, thus, stereoisomers of the 10′-apo-11′,12′-dihydroauroxanthiiv 10′-ols 8. Valenciaxanthin represents a modification of the common cleavage of carotenoids in higher plants according to the scheme C40 → C27 + C13, insofar as the reduction step not only includes the aldehyde function but also the subsequent conjugated double bond.
    Additional Material: 4 Ill.
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  • 17
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 103 (1991), S. 671-689 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Wir geben einen Überblick Über Farbstoffe aus Blüten und Früchten alter und moderner Rosen und können zeigen, daß die gelben Farben der Rosen durch Carotinoide, die roten durch Anthocyanine und die modernen orangeroten durch ein Gemisch beider erzeugt werden. Der großen strukturellen Vielfalt bei Carotinoiden steht eine überraschend geringe bei Anthocyaninen gegenüber. Bei den Carotinoiden aus Rosenblüten ist der Zusammenhang zwischen Struktur und verwendetem Kreuzungspartner evident: alte gelbe Rosen, entstanden durch Einkreuzen von chinesischen Sorten, besitzen vorwiegend Carotinoide aus frühen Biogenesestufen, neuere gelbe Rosen mit Abstammung von mittelasiatischen Foetida-Typen führen dagegen weiterführende Hydroxylierungen, Epoxidierungen und Epoxidtransformationen mit Leichtigkeit aus. Ein neuer Carotinoidabbau verläuft nach dem Schema C40 → C13 + C27 → C13 + C14, wobei die C13-Verbindungen Duftstoffe sind. Für die Stabilisierung der Anthocyanin-Chromophore im physiologischen pH-Bereich ist die Copigmentierung mit Flavonolglycosiden wesentlich. Viele Rosenblüten, so auch diejenigen der früher medizinisch verwendeten Apothekerrose, enthalten große Mengen von stark adstringierend wirkenden Ellagitanninen, die Ester aus Monosacchariden und Gallussäure sind.
    Additional Material: 15 Ill.
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  • 18
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 30 (1991), S. 654-672 
    ISSN: 0570-0833
    Keywords: Flower colors ; Anthocyanins ; Rose pigments ; Color ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In this article we present a survey of the pigments found in the flowers and fruits of old and modern varieties of roses. The yellow colors are produced by carotenoids, the reds by anthocyanins, and the modern oranges by a mixture of the two. The great structural diversity of the carotenoids contrasts with a surprisingly small number of anthocyanins. For the carotenoids found in roses, a clear correspondence exists between the structure and the breeding partners used; the old yellow roses, which arose from crosses with Chinese varieties, mainly contain carotenoids from early stages in the biosynthesis, while in the modern yellow roses, which are descended from Central Asian foetida types, hydroxylations, epoxidations, and epoxide transformations readily occur. A recently elucidated carotenoid degradation sequence follows the scheme C40 → C13 + C27 → C13 + C14. The C13 compounds are odoriferous substances that contribute to the scent of roses. In the physiological pH region, copigmentation with flavonol glycosides is crucial for stabilization of the anthocyanin chromophores. Many roses, including the “apothecary's rose”, which was once used medicinally, contain large amounts of strongly astringent ellagitannins, monosaccharide esters of gallic acid.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
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