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  • 1
    ISSN: 0749-1581
    Keywords: Caryodaphnosis tonkinensis ; Lauraceae ; eupomatenoids ; 1H and 13C chemical shift assignment ; delayed COSY ; 1D NOE difference ; HMQC ; HMBC ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Eupomatenoids 3-6 and 13 were isolated from Caryodaphnosis tonkinensis and their 1H and 13C NMR spectra were assigned using 1D and 2D NMR techniques. Different assignment strategies are presented for the 1H and 13C chemical shifts. 1D NOE difference spectra, 1D APT, HMQC, HMBC, H,H-COSY-90 and delayed H,H-COSY-45 were used.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Five flavonoids were isolated from stems of Jatropha variegata (Forsk.) Vahl, the structures of which were identified as kaempferol 3-O-α-rhamnopyranoside, 3-O-α-L-arabinopyranoside, 3-O-β-D-glucopyranoside, 3-O-β-D-galactopyranoside and kaempferol.
    Additional Material: 4 Tab.
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  • 3
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The relationship between structure and circular dichroism was studied for a series of cardenolides including some compounds with saturated lactone ring.
    Additional Material: 1 Tab.
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  • 5
    ISSN: 1052-9306
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Some trimethylsilyl derivatives of nicotianamine and related amino acids have been studied by capillary gas chromatography/mass spectrometry. This method gives useful data for structure determination.
    Additional Material: 2 Tab.
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  • 6
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 3β-Amino-5α-solanidan (IVa), 3α-Amino-5β-solanidan (Xa) und 3β-Amino-5β-solanidan (XIa) wurden synthetisiert. Die 3-Amino-Gruppe dieser Verbindungen wurde mit salpetriger Säure umgesetzt. Die dabei erzielten Ergebnisse (Tab. 2) werden diskutiert.
    Additional Material: 2 Tab.
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  • 7
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the “Normalizing Factor” for the Tomato Mutant chloronerva, XX  -  Homologues of NicotianamineThe syntheses of the nicotianamine homologues (2S,αS)-α-〈[(4S)-4-amino-4-carboxybutyl]-amino)-2-carboxy-1-azetidinepentanoic acid (8) and the corresponding proline compound 11 were achieved by stepwise combination of the ethyl esters of (S)-2-azetidinecarboxylic acid or (S)-proline with ethyl (S)-5-oxo-2-(trifluoroacetylamino)pentanoate (4) via reductive coupling. The amino acids 8 and 11 exhibit no biological effect on the phenotypical normalization of the tomato mutant chloronerva.
    Notes: Die Homologen des Nicotianamins (2S,αS)-α-〈[(4S)-4-Amino-4-carboxybutyl]amino〉-2-carboxy-1-azetidinpentansäure (8) und die entsprechende Prolin-Verbindung 11 wurden durch stufenweise reduktive Vereinigung der Ethylester von (S)-2-Azetidincarbonsäure oder (S)-Prolin mit (S)-5-Oxo-2-(trifluoracetylamino)pentansäure-ethylester (4) synthetisiert. Die Aminosäuren 8 und 11 zeigen keine biologische Wirkung auf die phänotypische Normalisierung der Tomatenmutante chloronerva.
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  • 8
    ISSN: 0170-2041
    Keywords: Teinemine and 22-isoteinemine ; Etioline and 25-isoetioline ; Solanum steroid alkaloids ; Steroids ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The rare 16α-hydroxylated steroid alkaloids teinemine [(22S,25S)-22,26-epiminocholest-5-ene-3β,16α-diol, 8], 22-isoteinemine [(22R,25S)-22,26-epiminocholest-5-ene-3β,16α-diol, 10], etioline [(25S)-22,26-epiminocholesta-5,22(N)-diene-3β,16α-diol, 12], and 25-isoetioline [(25R)-22,26-epiminocholesta-5,22(N)-diene-3β,16α-diol, 21] are synthesized from the abundant spirosolane alkaloids tomatid-5-en-3β-ol [(25S)-22βN-spirosol-5-en-3β-ol, 1] and solasodine [(25R)-22αN-spirosol-5-en-3β-ol, 15], respectively. The crucial stages of these syntheses are the conversions of 1 or 15 into the N-protected (22S,25S)-, (22R,25S)-, and (22S,25R)-22,26-epimino-3β-hydroxycholest-5-en-16-ones 6, 7, and 18 as well as their reductions with sodium/ 2-propanol to the 16α-hydroxy compounds teinemine (8), 22-isoteinemine (10), and (22S,25R)-22,26-epiminocholest-5-ene-3β,16α-diol (19), respectively. By treatment with sodium methanolate the N-chloro derivatives 9 and 11 of 8 and 10 afford etioline (12). In an analogous manner, the N-chloro derivative 20 of 19 is converted into 25-isoetioline (21).
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1992 (1992), S. 1091-1093 
    ISSN: 0170-2041
    Keywords: Solasodines ; Tomatidines ; Alkaloids ; Solanum steroid alkaloids ; Spirosolanes ; Steroids ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The N-Hydroxyspirosolane alkaloids N-hydroxysolasodine (1) and N-hydroxytomatidine (10) as well as the N-hydroxy-22,26-epiminocholestene 7 have been prepared by oxidation of the respective amines 2, 11, and 5 with hydrogen peroxide in the presence of selenium dioxide.
    Additional Material: 2 Tab.
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 723 (1969), S. 159-180 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Solanum-Alkaloids, LXXXVII1). Structure and Synthesis of SolanocapsineAccording to former investigations solanocapsine was considered to be 3β-amino-22.26-epimino-16β.23-epoxy-5α.22αH.25βH-cholestan-23β-ol (1). 1 was synthesized from solasodine (4) in 10 steps, but was shown to be not identical with solanocapsine. By NMR spectroscopy and, after transformation into the 16-hydroxy compound 34, by molecular rotation differences, the 16α-epoxy structure (3β-amino-22.26-epimino-16α.23-epoxy-5α.22αH.25βH-cholestan-23β-ol, 30 and 41) of solanocapsine was established. - The synthesis of compound 1 from solasodine (4) included the introduction of a keto group at C-23 by selenium dioxide oxidation of the cyclic azomethines 6 or 7, which are easily obtainable from 4 and 5, respectively, catalytic hydrogenation of the 23-ketones 8 and 9 to the piperidinols 10 and 14, and N-carbobenzoxylation, followed by oxidation of the hydroxy group at C-23 affording ketone 18. Hydrolysis of the acetoxy groups of ketone 18, accompanied by intramolecular hemiketalization, gave N-benzyloxycarbonyl-22.26-epimino-23β-methoxy-16β.23-epoxy-5α.22αH.25βH-cholestan-3β-ol (23). Dehydrogenation of the hydroxy group at C-3, transformation of the 3-ketone 24 into the oxime 25, cleavage of the carbobenzoxy group and hydrogenation yielded compound 1. Constitution and stereochemistry of all intermediates were proved by use of chemical and physical methods.
    Notes: Dem Steroidalkaloid Solanocapsin sollte auf Grund früherer Arbeiten die Struktur 3β-Amino-22.26-epimino-16β.23-epoxy-5α.22αH.25βH-cholestan-23β-ol (1) zukommen. Verbindung 1 wurde in 10 Stufen aus Solasodin (4) synthetisiert, erwies sich jedoch als nicht identisch mit Solanocapsin. Für dieses wurde nunmehr durch NMR-Spektroskopie und nach Überführung in die 16-Hydroxy-Verbindung 34 mit Hilfe von molaren Rotationsdifferenzen die 16α-Epoxy-Struktur (3β-Amino-22.26-epimino-16α.23-epoxy-5α.22αH.25βH-cholestan-23β-ol, 30 und 41) bewiesen. Die Stereochemie von Solanocapsin (30) und Syntheseprodukt 1 an C-22 und C-23 ergab sich auf Grund reaktionskinetischer und thermodynamischer Überlegungen sowie Kernresonanzmessungen. - Die Synthese von Verbindung 1 aus Solasodin (4) umfaßte die Einführung einer 23-Keto-Gruppe durch Selendioxid-Oxidation der aus 4 oder 5 leicht zugänglichen cyclischen Azomethine 6 bzw. 7, die katalytische Hydrierung der so gewonnenen 23-Ketone 8 und 9 zu den Piperidinolen 10 und 14, N-Carbobenzoxylierung sowie anschließende Oxidation der 23-Hydroxy-Gruppe unter Bildung von 18, das nach Hydrolyse der Acetoxygruppen unter intramolekularer Hemiketalisierung das N-Benzyloxycarbonyl-22.26-epimino-23β-methoxy-16β.23-epoxy-5α.22αH.25βH-cholestan-3β-ol (23) lieferte. Dehydrierung der 3β-Hydroxy-Gruppe, nachfolgende Oximierung des 3-Ketons 24 zu 25, Abspaltung des Carbobenzoxy-Restes und Hydrierung ergaben schließlich 1. Konstitution und Stereochemie sämtlicher Synthesezwischenprodukte wurden durch chemische und physikalische Methoden ermittelt.
    Additional Material: 2 Ill.
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