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  • 1
    ISSN: 1520-4804
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 95 (1962), S. 985-995 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Racem. Tetralin-p-chinol wird über die Strychninsalze der sauren 3-Nitro-phthal-säureester in die optischen Antipoden zerlegt. Die Konfiguration und Konformation der Antipoden wird diskutiert und zur Konfiguration und Konformation der östra-p-chinole auf Grund des optische Verschiebungssatzes und der Rotationsdispersion in Beziehung gesetzt. Daraus ergibt sich die absolute Konfiguration der Antipoden des Tetralin-p-chinols.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 105 (1972), S. 2800-2804 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Alkoxysulfonyl IsocyanatesThermal decomposition of compounds of the general structure 4 affords alkoxysulfonyl isocyanates 5, a new class of highly reactive isocyanates.
    Notes: Durch thermische Zersetzung von Verbindungen der allgemeinen Struktur 4 werden Alkoxy-sulfonylisocyanate 5, eine neue Klasse hochreaktiver Isocyanate, gewonnen.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 96 (1963), S. 639-650 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die tertiäre Hydroxylgruppe von p-Chinolen läßt sich in schwach saurem Milieu veräthern. In schwach basischem Medium bilden sich mit genügend reaktionsfähigen Säurechloriden und -anhydriden p-Chinolester, die sich durch basenkatalysierte Umesterung in Methanol spalten lassen, Bildungs- und Spaltungsgeschwindigkeiten von p-Chinolacetaten zeigen, daß die tertiäre Sauerstoffunktion in der Reihe Tolu-p-chinol, Tetralin-p-chinol, Östra-p-chinol-(10β) zunehmend sterisch gehindert ist.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 0947-3440
    Keywords: Cephalosporin, prodrug of ; Antibiotics ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: HR 916 K (5), the 1-(S)-(pivaloyloxy)ethyl prodrug ester of the cephalosporin cefdaloxime, exhibits a significantly higher oral bioavailability than the 1-(R) diastereomer HR 916 J. An efficient synthesis of HR 916 K was developed. The separation of the diastereomers was achieved by precipitation of the 1-(R)-hydrochloride 9 followed by crystallization of the 1-(S)-amine 10 (de 〉 96%). The 1-(R) diastereomer 9 was recycled by acidic saponification or enzymatic cleavage to AMCA (7). The amine 10 was acylated with mercaptobenzothiazole thioesters or mixed anhydrides, prepared from carboxylic acids 13 and 14, in almost quantitative yield. Deprotection of the oxime and formation of the tosylate proceeded in one step. Using thioester 18, we obtained HR 916 K (5) from AMCA (7) in 42% yield.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 722 (1969), S. 132-141 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloaddition Reactions with α,β-Diheterosubstituted Olefins, I. Reactions with Sulfonyl IsocyanatesThe reaction of sulfonyl isocyanates with α,β-dialkoxy substituted olefins yields N-sulfonyl-3,4-dialkoxy-2-azetidinon compounds 3 as main products and N-sulfonylcarboxylamide compounds 4. Kinetic studies on the formation of β-lactams 3 are reported and the reactions of these compounds with methanol are described. The formation of β-lactams from α,β-sulfur and nitrogen substituted olefins can be detected by i.r.spectroscopy.
    Notes: Sulfonylisocyanate reagieren mit α.β-disauerstoffsubstituierten Olefinen unter 1.2-Addition zu 1-Sulfonyl-3.4-dialkoxy-azetidinon-(2)-Verbindungen 3. Daneben bilden sich durch Substitution α.β-ungesättigte N-Sulfonyl-carbonsäureamid-Verbindungen 4. Mit Schwefel-und Stickstoff-substituierten Olefinen wird eine Azetidinon-Bildung IR-spektroskopisch nachgewiesen. Reaktionsweisen sowie kinetische Untersuchungen zur Bildung der β-Lactam-Derivate 3 werden beschrieben.
    Additional Material: 7 Tab.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1974 (1974), S. 1361-1390 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 4-Mercapto-2-azetidinones, II. - Synthesis and Reactions of 4-Mercapto-2-azetidinones4-Tritylthio-2-azetidinones 1 react with mercury salts and with methoxycarbonylmercury acetate to yield the thio compounds 2 and the 4-(methoxycarbonylmercurythio)-2-azetidinones 3, respectively. Compounds 1 react with silver salts to give the thio compounds of silver 5. 4-Mercapto-2-azetidinones 4 can be prepared by reaction of the compounds 2, 3, and 5 with hydrogen sulfide. Both the reaction of these new β-lactam derivatives with alkylating agents to yield compounds 12 and addition reactions of double bonds are described. The direct alkylation of the thio compounds of mercury 2, 3, and of the thio compounds of silver 5 also yields the alkylation products 12. Solvolysis of the mercury compounds 2 and 3 with excess mercury(II) acetate leads to the methoxy compound 15 and the acetoxy compounds 16. 4-Mercapto-2-azetidinones containing an α-isopropylidene acetate function on nitrogen are investigated regarding their possible occurrence in penicillin chemistry.
    Notes: 4-Tritylthio-2-azetidinone 1 reagieren mit Quecksilbersalzen zu den Thioverbindungen 2, mit Methoxycarbonylquecksilberacetat zu den 4-(Methoxycarbonylquecksilberthio)-2-azetidinonen 3, sowie mit Silbersalzen zu den Silberthioverbindungen 5. Aus den Thioverbindungen 2, 3 und 5 werden mit Schwefelwasserstoff die 4-Mercapto-2-azetidinone 4 freigesetzt. Die Alkylierung der SH-Gruppe dieser reaktiven, neuen β-Lactamderivate zu den Verbindungen 12 sowie Additionen an Doppelbindungen werden beschrieben. Die direkte Alkylierung der Quecksilberthioverbindungen 2 und 3 sowie der Silberthioverbindungen 5 führt ebenfalls zu den Alkylierungsprodukten 12. Die Solvolyse der Quecksilberverbindungen 2 und 3 mit überschüssigem Quecksilberacetat führt zur Methoxyverbindung 15 und den Acetoxyverbindungen 16. 4-Mercapto-2-azetidinone mit einer α-Isopropylidenacetatfunktion am Stickstoff werden hinsichtlich ihres möglichen Auftretens in der Penicillinchemie untersucht.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 722 (1969), S. 142-154 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloaddition Reactions with α,β-Diheterosubstituted Olefins, II1). Reactions with Acyl IsocyanatesAcylisocyanates react with α,β-dialkoxy substituted olefins to yield 1,2-adducts, N-acyl-3,4-dialkoxy-azetidin-2-ones 3 together with 1,4-adducts, 5,6-dihydro-4H-1,3-oxazin-4-ones 4. Kinetic studies on the formation of compounds 4 are reported and some of their reactions are described. - Enamines and some alkyl substituted olefins give similar cycloaddition products with acyl isocyanates.
    Notes: Acylisocyanate reagieren mit α.β-disauerstoff-substituierten Olefinen nebeneinander unter 1.2-Addition zu N-Acyl-3.4-dialkoxy-azetidinonen-(2) 3 und 1.4-Addition zu 5.6-Dihydro-4H-1.3-oxazinonen-(4) 4. Reaktionsweisen der dargestellten Verbindungen sowie kinetische Untersuchungen ihrer Bildung werden beschrieben. - Enamine und einige Alkyl-substituierte Olefine ergeben ähnliche Cycloadditionsprodukte mit Acylisocyanaten.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Studies on the Total Synthesis of Cephalosporin Derivatives, III1). - Synthesis of Cephem Derivatives by Ring Closure Reactions of cis-3-Phenylacetamido-4-alkylthio-2-azetidinonescis-3-Phenylacetamido-4-alkylthio-2-azetidinones 1 with ketone functions in the side chains attached to sulfur and nitrogen can be cyclized to yield Δ3- and Δ2-cephem derivatives 2 and 3, respectively. The isomeric compounds 4 are also obtained. The transformation of the Δ2-cephem compounds 3 into the Δ3-cephem compounds 4 is described.
    Notes: cis-3-Phenylacetamido-4-alkylthio-2-azetidinone 1 mit Ketonfunktionen in den Seitenketten an Schwefel und Stickstoff können zu Δ3- und Δ2-Cephemverbindungen 2 bzw. 3 cyclisiert werden. Daneben werden die isomeren Verbindungen 4 erhalten. Die Umwandlung der Δ2-Cephemverbindungen 3 in die Δ3-Cephemverbindungen 4 wird beschrieben.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1974 (1974), S. 870-900 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Studies on the Total Synthesis of Cephalosporin Derivatives, I. - Synthesis of trans-3-Sulfonyloxy-4-alkylthio-2-azetidinonesThe reaction of sulfonyloxyacetyl chlorides 1 with thioformimidates 2 in the presence of triethylamine yields trans-3-sulfonyloxy-4-alkylthio-2-azetidinones 3. These new β-lactam derivatives are also prepared by the reaction of acyloxyacetyl chlorides 8 with thioformimidates 2 to give 3-acyloxy-2-azetidinones 9. Subsequent saponification affords 3-hydroxy compounds 10 which are esterified with sulfonyl chlorides. Ozone oxidation of unsaturated residues in these β-lactams leads to the corresponding carbonyl derivatives. The reaction of Δ2-thiazolines and 5,6-dihydro-4H-1,3-thiazines with sulfonyloxyacetyl chlorides to yield bicyclic β-lactam derivatives is also described.
    Notes: Sulfonyloxyacetylchloride 1 reagieren mit Thioimidsäureestern 2 in Gegenwart von Triäthylamin zu trans-3-Sulfonyloxy-4-alkylthio-2-azetidinonen 3. Ein weiterer Weg zu dieser neuen Klasse von β-Lactamderivaten besteht in der Reaktion von Acyloxyacetylchloriden 8 mit Thioimidsäureestern 2, Verseifung der gebildeten 3-Acyloxy-2-azetidinone 9 zu den 3-Hydroxyverbindungen 10 und deren Veresterung mit Sulfonsäurechloriden. Ungesättigte Reste an Schwefel und Stickstoff in den dargestellten β-Lactamen werden mit Ozon unter Bildung von Carbonylfunktionen oxidiert. Die Reaktion von Δ2-Thiazolinen und 5,6-Dihydro-4H-1,3-thiazinen mit Sulfonyloxyacetylchloriden zu bicyclischen β-Lactamderivaten wird beschrieben.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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