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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 104 (1971), S. 3556-3566 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Configuration of the Jaborosalactones, a New Degradation Scheme for WithanolidesThe 14α.17αH.20S-configuration in the Jaborosalactones was demonstrated by the degradation of Jaborosalactone D (4a) to known steroids. A new degradation scheme was used, the crucial steps of which were the hydrogenation of 6 to give 7, the hydrogenolysis of 9, and the ether cleavage in 15.
    Notes: Die 14α.17αH.20S-Konfiguration der Jaborosalactone wurde durch Verknüpfung von Jaborosalacton D (4a) mit bekannten Steroiden bewiesen. Es wurde ein neuer Withanolid-Abbau entwickelt, dessen entscheidende Schritte die Reduktion von 6 zu 7, die Hydrogenolyse von 9 und die Ätheröffnung bei 15 sind.
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 106 (1973), S. 576-586 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Hydrogenolysis of Some 6β-Acetoxy- and 6β-Hydroxy-Steroid Δ4-OlefinsThe hydrogenolysis of the compounds 1, 4, 8, 9, and 10 with palladium as catalyst furnished a mixture of the corresponding Δ4- and Δ5-olefins. The results can be rationalized by assuming the formation of an intermediate π-allyl complex which is reduced to form the Δ4- and the Δ5-olefin. Hydrogenation of 8 with platinum in acetic acid gave the two 5β-steroids 6 and 7.
    Notes: Die Hydrogenolyse der Verbindungen 1, 4, 8, 9 und 10 über einem Palladium-Katalysator lieferte ein Gemisch der entsprechenden Δ4- und Δ5-Olefine. Die Ergebnisse können so interpretiert werden, daß intermediär ein π-Allyl-Komplex auftritt, der zum Δ4- und zum Δ5-Olefin reduziert wird. Über Platin in Eisessig ergab 8 die beiden 5β-Steroide 6 und 7.
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 111 (1978), S. 3086-3093 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Conversion of 17α-Ethinyl-17β-nitrooxy Steroids into 17α-Hydroxy-20-oxopregnane DerivativesTreatment of the 17α-ethinyl steroids 1a, b and their 17β-acetates 1c, d in alcoholic solution in the presence of mercury salt catalysts leads to the formation of 20-oxoisopregnenes 2a-d. Under the same conditions, 17β-nitrates 3a and b react with inversion of the side chain to yield the 17α-alkoxy-20-ketones 4a-c. In formic or acetic acid solution from 3a, b the 17-acyloxy-20-ketones 4d, e, and h are obtained which can be converted into the 17α-hydroxy derivatives 4f, g by saponification. When silver acetate is used as catalyst in formic acid/hexamethylphosphoric triamide solutions, from 3a and b the 17β-ethinyl-17α-formyloxy compounds 6a and b are formed which can be hydrated to the 20-ketones 4d and e by subsequent treatment with mercury acetate.
    Notes: Die 17α-Ethinyl-Steroide 1a, b und deren 17β-Acetate 1c, d lassen sich in alkoholischer Lösung unter Quecksilbersalzkatalyse in die 20-Oxoisopregnene 2a-d überführen. Dagegen reagieren die 17β-Nitrooxy-Steroide 3a, b bei analogen Reaktionsbedingungen unter Inversion der Seitenkette zu den 17α-Alkoxy-20-ketonen 4a-c. Mit Ameisen- oder Essigsäure werden aus 3a, b die 17-Acyloxy-20-ketone 4d, e und h erhalten, die sich zu den 17-Hydroxy-Verbindungen 4f und g verseifen lassen. Verwendet man Silberacetat als Katalysator, so bilden sich im Ameisensäure/Hexamethylphosphorsäuretriamid-Gemisch aus 3a und b die 17β-Ethinyl-17α-formyloxy-Steroide 6a und b, die mit Quecksilber(II)-acetat zu den 20-Ketonen 4d und e hydratisieren.
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 113 (1980), S. 3827-3836 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Steroidal Butyrolactones from 3β,21-Diacetoxy-16α,17-epoxy-5-pregnen-20-oneChemical and microbiological rearrangement from 1 to 2 is described. The configurations of C-16, C-17 and C-20 have been determined by chemical transformations of 2 and spectroscopic data of their reaction products.
    Notes: Es wird die chemische und mikrobiologische Umlagerung des Epoxids 1 zum Lacton 2 beschrieben. In 2 werden die Konfigurationen an C-16, C-17 und C-20 durch chemische Reaktionen und spektroskopische Daten von Reaktionsprodukten bestimmt.
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 111 (1978), S. 3094-3104 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A Novel, Simple Cyclopropane SynthesisOlefins RR′C = CXY in which X and Y are electron attracting substituents (CN or CO2R″), can be transformed in good yields with nitromethane and bases into the corresponding cyclopropyl derivatives. The mechanism, steric course, and limits of the reaction are discussed.
    Notes: Die Olefine RR′C = CXY, in denen X und Y elektronenanziehende Substituenten (CN oder CO2R″) sind, lassen sich mit Nitromethan und Basen in guten Ausbeuten in die entsprechenden Cyclopropylverbindungen umwandeln. Mechanismus. sterischer Verlauf und Grenzen der Reaktion werden diskutiert.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1989 (1989), S. 997-1001 
    ISSN: 0170-2041
    Keywords: Steroids ; Androstane, derivative ; Antialdosteron test ; Vasoconstriction test ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Steroids with 17-Spiro-dithiolanone StructureUtilizing a newly developed cyclization reaction in the pregnane side chain, the compound 3 was transformed into the dithiolanones 6 and 7 which are of interest as potential diuretic agents. Compounds 13a - 13c, possessing a structural similarity to corticosteroids, can be prepared from the corresponding 17-(acyloxy)-21-(mesyloxy) derivatives 12a - 12c by treatment with a 10-fold excess of potassium thioacetate.
    Notes: Mit Hilfe einer neuen Abwandlung in der Pregnan-Seitenkette von 3 wird die Synthese der Dithiolanone 6 und 7 als potentiell wirksame Diuretica beschrieben. Die corticoidnahen Strukturen 13a - 13c mit einer Dithiolanon-Seitenkette lassen sich aus den entsprechenden 17-(Acyloxy)-21-(mesyloxy)-Derivaten 12a - 12c durch Behandlung mit einem 10fachen molaren Überschuß an Kaliumthioacetat darstellen.
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1983 (1983), S. 705-711 
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 17-Pivalate Derivatives of PregnaneThe sterically hindered hydroxy group at C-17 of pregnane derivatives can be esterified by pivalic anhydride/4-(dimethylamino)pyridine only in the presence of an acetoxy group at C-21. Starting from 4c, the synthesis of corticosteroid 6 can be achieved via 5c by application of this method. However, the 21-deoxypivalate 2e can be obtained only by intramolecular transesterification of 1d to yield 2b, followed by mesylation, and reduction of the corresponding bromide 2d. Further transformation of 2e into the 6α-methyl compound 8 proceeds by transfer hydrogenation and isomerization of the intermediate 6-methylene steroid 7.
    Notes: Die sterisch gehinderte 17-Hydroxygruppe in Pregnanen läßt sich nur in Gegenwart einer 21-Acetoxygruppe mit Pivalinsäureanhydrid/4-(Dimethylamino)pyridin verestern. Nach dieser Methode wird aus 4c über 5c das Corticosteroid 6 synthetisiert. Dagegen kann das 21-Desoxy-17-pivalat 2e nur auf Umwegen aus dem 21-Pivalat 1d über das Umlagerungsprodukt 2b, das Mesylat 2c und das 21-Bromid 2d hergestellt werden. Die weitere Überführung in das 6α-Methylderivat 8 erfolgt über das 6-Methylensteroid 7.
    Additional Material: 1 Tab.
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  • 8
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A One-step Synthesis of 17-Acetoxy-6-methyl-4,6-pregnadiene-3,20-dione (Megestrol Acetate) from 17-Acetoxy-4-pregnene-3,20-dioneStarting from 17-Acetoxy-4-pregnene-3,20-dione (3), a one-step synthesis of megestrol acetate (5) is described.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1981 (1981), S. 1973-1981 
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis of 3-Methoxy-18-methyl-1,3,5(10),15-östratetraen-17α-olThe transformation of the 16α,17-epoxide 4 into the allyl alcohol 9 has been achieved via the bromohydrin 5 and the tetrahydropyranyl ether 6 or in a „one-pot“ procedure by oxidation of the 16β-phenyl selenide 12 to the products 14, 16, and 18. From the two 16β-phenyl sulfoxides 13 and 15, only the sulfoxide 13 with R configuration reacts thermally to yield the allyl alcohol 9 which can also be prepared from the piperidine N-oxide 8. The configuration of the phenyl sulfoxides 13 and 15 as well as of the corresponding phenyl selenoxides 14 and 16 has been determined by circular dichroism investigations. For the first time it has been possible to isolate a steroidal selenium analog 18 corresponding to the phenyl sulfone 17.
    Notes: Die Überführung des 16α,17-Epoxids 4 in den Allylalkohol 9 gelingt über das Bromhydrin 5 und den Pyranylether 6 oder im Eintopfverfahren über das 16β-Phenylselenid 12 und dessen Oxidationsprodukte 14, 16 und 18. Von den 16β-Phenylsulfoxiden 13 und 15 reagiert thermisch nur das (R)-konfigurierte 13 zum Allylalkohol 9, der sich ebenfalls aus dem Piperidin-N-oxid 8 herstellen läßt. Die konfigurative Zuordnung der Phenylsulfoxide 13 und 15 sowie der entsprechenden Phenylselenoxide 14 und 16 ließ sich durch CD-Spektren ermitteln. Erstmalig konnte bei Steroiden ein dem Phenylsulfon 17 entsprechendes Selen-Analogon 18 isoliert werden.
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1989 (1989), S. 991-995 
    ISSN: 0170-2041
    Keywords: Steroids ; Pregnane, derivatives ; Androstane, derivatives ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: New Rearrangements in the Pregnane Side ChainReaction of 17-acetoxy-21-(acetylthio)-4-pregnene-3,20-dione (3) with a large excess of sodium azide in methanol yields a mixture of rearrangement products consisting of the methyl etianate 11 and the spirodithiolanone 12. The influence of temperature and solvent on the progress of the reaction has been studied. In order to obtain further informations pertaining to the mechanism of rearrangement, the compounds 4-10, the 6α-methyl and the D-homo substances 13b and 13d have been synthesized and subjected to the conditions of rearrangement.
    Notes: 17-Acetoxy-21-(acetylthio)-4-pregnen-3,20-dion (3) reagiert mit einem großen Überschuß an Natriumazid in Methanol zu einem Gemisch der Umlagerungsprodukte Etiansäure-methylester 11 und Spirodithiolanon 12. Der Reaktionsablauf wird in Abhängigkeit von Reaktionstemperatur und Lösungsmittel untersucht. Um weitere Einblicke in einen möglichen Umlagerungsmechanismus zu gewinnen, werden die Verbindungen 4-10, die 6α-Methyl- und die D-Homoverbindungen 13b und 13d als Modellsubstanzen synthetisiert und den Umlagerungsbedingungen unterworfen.
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