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  • 1
    Electronic Resource
    Electronic Resource
    Terpene und Terpen-Derivate, XIX. Zur selektiven Epoxidierung von rac-β-Curcumen Darstellung von 1-(4-Methyl-1,4-cyclohexadien-1-yl)ethanon (1986)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1986 (1986), S. 1248-1254 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Terpenes and Terpene Derivatives, XIX. - On the Selective Epoxidation of rac-β-Curcumene. Synthesis of 1-(4-Methyl-1,4-cyclohexadien-1-yl)ethanoneExpoxidation of rac-β-curcumene (1) yields a mixture containing the monoepoxides 2 - 4, and 6 in a ratio of 4:1:5:1 besides some other products. - Birch reduction of 17 gives only the hydrocarbon 18, even via the alkoxide. - The uncatalyzed Diels-Alder reaction of isoprene (10) with 3-butyn-2-one (11) leads to a mixture of the ketones 12 - 15 with a large amount of the 1,5-isomer 13 and the acetophenones 14 and 15. By TiCl4 catalysis the regioselectivity 12/13 can be enhanced to 94:6.
    Notes: Epoxidierung von rac-β-Curcumen (1) ergibt ein Gemisch, das neben anderen Produkten die Monoepoxide 2 - 4 und 6 im Verhältnis 4:1:5:1 enthält. - Die nichtkatalysierte Diels-Alder-Reaktion von Isopren (10) mit 3-Butin-2-on (11) führt zu einem Gemisch der Ketone 12 - 15 mit einem hohen Anteil des 1,5-Isomeren 13 sowie der Acetophenone 14 und 15. Durch TiCl4-Katalyse kann die Regioselektivität 12/13 auf 94:6 verbessert werden.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198619860710
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  • 2
    Electronic Resource
    Electronic Resource
    Terpene und Terpen-Derivate, XXI. Synthese von rac-4,5-Dihydro-β-curcumen-4,5-diol (1987)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1987 (1987), S. 1013-1014 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Terpenes and Terpene Derivatives, XXI. - Synthesis of rac-4,5-Dihydro-β-curcumene-4,5-diolHydrolysis of the β-curcumene monoepoxide 1 afforded the title compound 2. - A second way started from the epoxy ketone 6. Hydrolysis (→ 7), formation of the THP ethers (→ 8, → 9), and reaction with homoprenyllithium leads to the allylic alcohol 3. After further protection (→ 4), Birch reduction, and subsequent hydrolysis a 1:4 mixture of the diols 2 and (E/Z)-11 was isolated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198719870864
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  • 3
    Electronic Resource
    Electronic Resource
    Synthese von 14,17-überbrückten 11β-Arylsteroiden (1989)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1989 (1989), S. 151-158 
    Details
    ISSN: 0170-2041
    Keywords: Antiprogestational activity ; Steroids, 11β-aryl-substituted ; Steroids, 14,17-ethano-bridged ; [4 + 2] Cycloaddition of steroidal 14,16-dienes ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis of 14,17-Bridged 11β-ArylsteroidsThe search for new progesterone antagonists led to the synthesis of 14,17-bridged 11β-arylsteroids. The key step was a stereo- and regioselective [4 + 2] cycloaddition of electron-deficient olefins to steroidal 14,16-dienes. The resulting new structures were examined with respect to progesterone receptor binding and to anti-progestational activity.
    Notes: Auf der Suche nach neuen Progesteron-Antagonisten wurden 14,17-überbrückte 11β-Arylsteroide synthetisiert. Schlüsselschritt des Verfahrens war die stereo- und regioselektive [4 + 2]-Cycloaddition elektronenarmer Olefine an steroidale 14,16-Diene. Die auf diese Weise zugänglichen neuen Strukturen wurden auf Progesteronrezeptor-Affinität und antigestagene Wirkung geprüft.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198919890130
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  • 4
    Electronic Resource
    Electronic Resource
    Friedel-Crafts-Reaktion von 2-Methylfuran mit gesättigten und α,β-ungesättigten Säureanhydriden (1985)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1985 (1985), S. 1935-1950 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Friedel-Crafts Reaction of 2-Methylfuran with Saturated and α,β-Unsaturated Acid Anhydrides2-Methylfuran (5) reacts with the saturated acid anhydrides 16 - 26 in the presence of SnCl4 to give the 2-acyl-5-methylfurans 37 - 47 selectively. The unsaturated anhydrides 27 - 32, however, yield mixtures which only in the case of senecioic acid anhydride (29) contain the respective primary product 48. Subsequent reactions lead to the addition products 55 (from 27) and 56 (from 29), and to (E,Z)-mixtures of their enol estes 57 - 62 which could partially be separated and assigned.  -  The olfactory properties of 2, 37 - 48, 50, 52, and 53 were investigated.
    Notes: 2-Methylfuran (5) reagiert mit den gesättigten Säuranhydriden 16 - 26 in Gegenwart von SnCl4, einheitlich zu den 2-Acyl-5-methylfuranen 37 - 47. Die ungesättigten Anhydride 27 - 32 ergeben dagegen Gemische, die nur im Falle von Seneciosäureanhydrid (29) auch das betreffende Primärprodukt 48 enthalten. Folgereaktionen führen zu den Additionsprodukten 55 (aus 27) und 56 (aus 29) sowie deren (E,Z)-Enol-Ester-Gemischen 57 - 62, die teilweise getrennt und zugeordnet werden konnten.  -  Die olfaktorischen Eigenschaften von 2, 37 - 48, 50, 52 und 53 wurden untersucht.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198519851003
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  • 5
    Electronic Resource
    Electronic Resource
    Terpene und Terpen-Derivate, XVIII. Zur Darstellung von rac-γ-Curcumen (1986)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1986 (1986), S. 1021-1029 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Terpenes and Terpene Derivatives, XVIII. - Concerning the Preparation of rac-γ-CurcumenePreparation of pure γ-curcumene (3) described by Birch in 1949 via dehydratization of the alcohol 5 with SOCl2/pyridine or Burgess reagent. Analogously the secondary alcohol 20 yielded mixtures of 3 and the 1,3-dienes 21 and (presumably) 22. - Li/NH3 reduction of the tert. benzyl alcohol 8 afforded after work-up directly the dienone 15 which with MeLi gave the dehydro derivative 16 of zingiberenol (17).
    Notes: Die von Birch 1949 beschriebene Darstellung reinen γ-Curcumens (3) durch Dehydratisierung des Alkohols 5 mit SOCl2/Pyridin konnte nicht reproduziert werden. Auch mit POCl3/Pyridin oder dem Burgess-Reagenz wurden aus 5 immer Gemische aus α-, β- und γ-Curcumen (1 - 3) erhalten. Analog lieferte auch der sekundäre Alkohol 20 Gemische aus 3 und den 1,3-Dienen 21 und (vermutlich) 22. - Die Li/NH3-Reduktion des tert. Benzylalkohols 8 führte nach Aufarbeitung direkt zum Dienon 15, das mit MeLi das Dehydroderivat 16 des Zingiberenols (17) ergab.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198619860607
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