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  • 1
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    Unknown
    Berlin : Periodicals Archive Online (PAO)
    Deutsche Zeitschrift für Philosophie. 25:10 (1977) 1279 
    ISSN: 0012-1045
    Topics: Philosophy
    Description / Table of Contents: REZENSIONEN
    Notes: Zum 60. Jahrestag der Grossen Sozialistischen Oktoberrevolution
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 309 (1979), S. 109-117 
    ISSN: 1432-1912
    Keywords: Oxyfedrine ; Partial agonist at β-adrenoceptors ; Norephedrine ; 3-Methoxyacrylophenone ; Theophylline
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Oxyfedrine, at concentrations of 10−7 to 3×10−6 mol/l, increased the force of contraction of the isolated papillary muscle of the guinea pig. It was difficult to abolish this effect by repeated exchange of the bath solution. The maximum inotropic action was about 40% that of noradrenaline. Peripheral catecholamine stores were not involved, neither were the breakdown products of oxyfedrine, norephedrine and 3-methoxyacrylophenone. The latter had positive inotropic actions at 10 times and 100 times higher concentrations, respectively, than the parent substance. Their inotropic effects were caused by the release of endogenous catecholamines. 2. The positive inotropic effect of oxyfedrine was not influenced by burimamide (10−4mol/l). (±)-Propranolol (10−9 and 10−8 mol/l) shifted the concentration-effect curve of oxyfedrine to the right. The inhibition of the inotropic effect by 10−7 mol/l(±)-propranolol was not surmountable. 3. In the presence of 10−6 mol/l propranolol, oxyfedrine had only a concentration-dependent negative inotropic action. This was due mainly to a decrease in contraction velocity and was accompanied by a shortening in the time to peak force. The duration of the transmembrane action potential and the depolarization speed were not reduced (10−5mol/l oxyfedrine). 4. The positive inotropic effect of oxyfedrine was enhanced by the phosphodiesterase inhibitor theophylline (10−4mol/l). The maximum of the concentration-effect curve of oxyfedrine, i.e., the efficacy of this substance, was almost doubled. 5. A quantitative analysis of the interaction of oxyfedrine with the positive inotropic effect of isoprenaline proved that oxyfedrine acted mainly as a partial agonist at cardiac β-adrenoceptors. Its positive inotropic effect due to stimulation of β-adrenoceptors was, to some extent, antagonized by its negative inotropic action.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: On the Conformational Behaviour of Substituted Phenylbenzoates - Molecular and Crystal Structure of the Nematogenic Compound 4′-(ß-Cyanoethyl)-phenyl-4-n-pentoxybenzoateThe title compound crystallizes in the monoclinic space group P21/n with a = 1567.6(2) pm, b = 915.5(1) pm, c = 1459.1(1) pm, β = 115.30(1)°, and four molecules per unit cell. The structure has been solved by direct methods and refined to R = 0.104. The molecules adopt a markedly stretched form and show a parallel arrangement of their long axes in the crystal lattice. The molecular and crystal structure is discussed in relation to the mesomorphic behaviour of the compound.A theoretical conformational analysis has been performed for the isolated phenylbenzoate molecule using the EPEN/2 method, its results are compared with the experimental torsion angles in a series of substituted phenylbenzoates.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Hydrazine and its Derivatives. 53. Synthesis of P-, As-, and Sb-substituted Hydrazines by Addition of P—H, As—H, and Sb—H Groups to N=N Double BondsAddition of diphenylphosphinous acid, diphenylthiophosphinous acid, methyl hydrogen phenylphosphonite, diethyl hydrogen phosphite, diphenylphosphane, dibutylphosphane, diphenylarsane, diethylarsane, and diphenylstibane to the N=N double bond of diethyl azodicarboxylate, dimethyl azodicarboxylate, ethyl phenylazocarboxylate, and azobenzene yields the P-, As-, and Sb- substituted hydrazines 1-23. The spectroscopic data agree with the structural formulae. The course of the reactions suggests a polar reaction mechanism except in the case of the synthesis of 15, which probably proceeds via radical intermediates. The azo systems employed show a distinct graduation in their ability to add to the element-hydrogen groups used.
    Notes: Durch Addition von Diphenylphosphinigsäure, Diphenylthiophosphinigsäure, Phenylphosphonigsäure-monomethylester, Phosphorigsäure-diäthylester, Diphenylphosphan, Dibutylphosphan, Diphenylarsan, Diäthylarsan und Diphenylstiban an die N=N-Doppelbindung von Azodicarbonsäure-diäthylester, Azodicarbonsäure-dimethylester, Phenylazocarbonsäure-äthylester und Azobenzol konnten die P-, As- und Sb-substituierten Hydrazine 1-23 synthetisiert werden. Die spektroskopischen Daten stehen mit den angeführten Konstitutionsformeln in Einklang. Der Reaktionsverlauf legt mit Ausnahme der Darstellung von 15, die über radikalische Zwischenstufen erfolgen dürfte, einen polaren Reaktionsmechanismus nahe. Die verwendeten Azosysteme zeigen eine deutliche Abstufung in der Bereitschaft zur Addition der eingesetzten Element-Wasserstoff-Funktionen.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
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