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  • Inorganic Chemistry  (7)
  • Acetone  (2)
  • Mass spectrometry  (2)
  • 1
    Electronic Resource
    Electronic Resource
    Investigation of salt — Mixed solvent systems. XXXVII. Crystallization enthalpy of lithium chloride in mixed solvent systems (1990)
    Springer
    Journal of solution chemistry 19 (1990), S. 437-446 
    Details
    ISSN: 1572-8927
    Keywords: Acetone ; enthalpy of crystallization ; enthalpy of dissolution ; enthalpy of transition ; ion-solvent interaction ; lithium chloride ; methanol ; N,N-dimethylformamide ; solvation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The crystallization enthalpy of LiCl at 25°C in LiCl-H2O-cosolvent systems is determined calorimetrically as a function of the cosolvent content in the mixed solvent. This parameter is used for the investigation of heat phenomena accompanying the solvation of the salt in a saturated solution. The cosolvents employed include methanol, acetone, and N,N-dimethylformamide. The most pronounced change is effected by replacement of water with N,N-dimethylformamide.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00650376
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  • 2
    Electronic Resource
    Electronic Resource
    Investigations of salt — Mixed solvent systems XXXVIII. Crystallization enthalpy of magnesium chloride in mixed solvent systems (1990)
    Springer
    Journal of solution chemistry 19 (1990), S. 447-455 
    Details
    ISSN: 1572-8927
    Keywords: Acetone ; enthalpy of crystallization ; enthalpy of dissolution ; enthalpy of transition ; ion-solvent interaction ; magnesium chloride ; methanol ; N,N-dimethylformamide ; solvation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The crystallization enthalpies of MgCl2 in MgCl2−H2O-cosolvent systems at 25°C were determined calorimetrically as a function of the cosolvent content in the mixed solvent. Methanol, acetone, and N,N-dimethylformamide were employed as cosolvents. The results show the individual cosolvents to have very differently influences on the energy state of the salt in the saturated solution. The most pronounced changes are effected by an increase of the DMF content in the mixed solvent. The intensity of Mg2+-DMF interaction at a higher DMF content in the saturated solution considerably exceeds the Li+-DMF interaction in LiCl solutions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00650377
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  • 3
    Electronic Resource
    Electronic Resource
    Determination of nitric oxide metabolites by means of the Griess assay and gas chromatography–mass spectrometry in the cavernous and systemic blood of healthy males and patients with erectile dysfunction during different functional conditions of the penis (2000)
    Springer
    Urological research 28 (2000), S. 364-369 
    Details
    ISSN: 1434-0879
    Keywords: Key words Nitric oxide metabolites ; Erectile dysfunction ; Griess reaction ; Gas chromatography ; Mass spectrometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Recent research implicated that the relaxation of cavernous arterial and trabecular smooth muscle – the crucial event in penile erection – is initiated by the release of nitric oxide (NO) from nerve terminals within the cavernous tissue as well as from the endothelia that line the lacunar spaces and the intima of penile arteries. The present study was undertaken to determine whether plasma levels of the NO metabolites nitrate (NO− 3) and nitrite (NO− 2) in the systemic and cavernous blood of male subjects change during different penile conditions, and whether there is a difference in the NO− 3 and NO− 2 levels of normal males and patients with erectile dysfunction (ED). Twenty-four potent adult male volunteers and 15 patients with ED were exposed to visual and tactile erotic stimuli in order to elicit penile tumescence and, in the group of healthy volunteers, rigidity. Whole blood was aspirated from the corpus cavernosum and the cubital vein, and NO− 3 and NO− 2 levels were determined in plasma aliquots by means of the Griess reaction and a method combining gas chromatography and mass spectrometry (GC-MS). The mean systemic and cavernous plasma NO3 −/NO2 − level in blood samples obtained from the healthy volunteers was 25–31 μM when determined by means of the Griess reaction and 37–41 μM when measured by GC-MS. Both approaches revealed that NO3 −/NO2 − levels in the peripheral and cavernous blood do not change appreciably during developing erection, rigidity and detumescence. Moreover, no significant differences were found between NO3 −/NO2 − plasma levels in the systemic and cavernous blood samples taken from the normal subjects and patients during penile flaccidity, tumescence and detumescence. Our results may reflect the fact that NO metabolism in the corpora cavernosa in the phases of penile tumescence and rigidity may account for only a minor fraction of local levels of NO3 − and NO2 −, which may also derive from exogenous sources. Moreover, the basal levels of NO metabolites in the blood flushing the lacunar spaces of the cavernous body in the state of developing erection could conceal any release of NO that may occur within the penile tissue. Thus, we conclude that the quantification of NO metabolites by means of advanced detection methods, such as GC-MS, is of no use in the workup of ED.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002400000141
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  • 4
    Electronic Resource
    Electronic Resource
    Stoffwechselprodukte von Mikroorganismen (1976)
    Springer
    Archives of microbiology 107 (1976), S. 143-160 
    Details
    ISSN: 1432-072X
    Keywords: New nucleoside-peptide antibiotic ; Chitin biosynthesis ; Structure elucidation ; Mass spectrometry ; Streptomyces tendae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Der Streptomycet Tü 901, Streptomyces tendae, bildet ein antifungisch wirkendes Nukleosid-Antibioticum, Nikkomycin. Als Angriffsort kommt die Chitinsynthese in Frage. Mit Hilfe der Massenspektrometrie und des chemischen Abbaus konnten Uracil, eine Aminohexuronsäure und eine neue, einen Pyridinring enthaltende Aminosäure nachgewiesen werden.
    Notes: Abstract From the fermentation broth of Streptomyces tendae Tü 901 a substance was isolated, which inhibits the growth of several fungi. The new antibiotic affects the chitchin biosynthesis. Its structure was identified by mass spectrometry of the products obtained after chemical degradation. Nikkomycin is a nucleoside-peptide antibiotic consisting of uracil, an amino hexuronic acid and a new amino acid containing a pyridin ring.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00446834
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  • 5
    Electronic Resource
    Electronic Resource
    Zur Chemie von Haftgruppen, VI über die Eignung verschiedener Aldehyde und Ketone als Haftgruppen für Monoalkohole (1991)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 1885-1885 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19911240831
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  • 6
    Electronic Resource
    Electronic Resource
    Über die Struktur einer neuen Modifikation des Phosphorsulfids P4S9 (1990)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 588 (1990), S. 139-146 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Structure of a New Modification of Phosphorus Sulfide P4S9A new modification of P4S9 is formed by the reaction of phosphorus pentasulfide with isopropanol in a molar ratio 1:4. The pure substance can be isolated by repeated fractional crystallization from CS2. This modification crystallizes in the monoclinic space group P21/n with a = 855.5 pm, b = 1263.7 pm, c = 1245.3 pm, β = 104.94°, Z = 4. Normally the P4S9 I crystallizes from its melts, only by shorttime heating the cubic modification (P4S9 II) is yielded.
    Notes: Bei der Reaktion von Phosphor(V)-sulfid mit Isopropanol im Molverhältnis 1:4 bildet sich eine neue Modifikation des P4S9. Die reine Substanz läßt sich durch mehrfache fraktionierte Kristallisation aus CS2 isolieren. Diese Modifikation kristallisiert in der monoklinen Raumgruppe P21/n mit a = 855,5 pm, b = 1263, 7 pm, c = 1245,3 pm, β = 104,94°, Z = 4. Nach kurzzeitigem Aufschmelzen kristallisiert die kubische Modifikation (P4S9 II), während längeres Schmelzen zur Kristallisation des P4S9 I führt.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19905880118
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  • 7
    Electronic Resource
    Electronic Resource
    Untersuchungen zur Darstellung des Phosphorsäurefluoridpyridiniumbetains, Py · PO2F (Py = Pyridin)Professor Günther Rienäcker zum 80. Geburtstage am 13. Mai 1984 gewidmet (1984)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 512 (1984), S. 72-78 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Studies on the Preparation of the Phosphoric Acid Fluoride Pyridinium Betaine, Py · PO2F (Py = Pyridine)Under anhydrous reaction conditions phosphoric acid chloride betaine, Py · PO2Cl (I), does not react with NaF or NaSO2F to the corresponding fluorine compound Py · PO2F (II). Reaction between AsF3 and I gives rise to the formation of compound II which is detectable by N.M.R.In an excess of pyridine POCl2F reacts with P4O10 to a mixture of I and II which are difficult to be separated. In a preparatively simple way II can be obtained by sulfur-oxygen exchange in liquid SO2 starting from dithiophosphoric acid fluoride betaine Py · PS2F.
    Notes: Versuche, ausgehend vom Phosphorsäurechloridpyrididiumbetain, Py · PO2Cl (I), unter wasserfreien Bedingungen durch Cl—F-Austausch das entsprechende Fluoridbetain, Py · PO2F (II), darzustellen, führen bei Verwendung von NaF und Natriumfluorosulfinat nicht zum Ziel, während bei der Reaktion mit AsF3 II im Reaktionsgemisch NMR-spektroskopisch nachgewiesen werden kann. Die Umsetzung von POCl2F mit P4O10 in überschüssigem Pyridin führt zu einem Gemisch aus I und II, aus dem jedoch II nur schwer isolierbar ist. In präparativ einfacher Weise kann II durch Schwefel-Sauerstoff-Austausch aus dem Dithiophosphorsäurefluoridbetain, Py · PS2F, in flüssigem SO2 erhalten werden.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19845120510
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  • 8
    Electronic Resource
    Electronic Resource
    Beiträge zur Chemie von Phosphorverbindungen mit Adamantanstruktur. VII[1]. Über Darstellung und Eigenschaften von Nonathio-cyclotriphosphatErweiterte und durch neuere Untersuchungen ergänzte Fassung eines Vortrages auf dem “2nd Symposium on Inorganic Phosphorus Compounds”, Prag 1974. (1982)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 494 (1982), S. 49-54 
    Details
    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 Phosphorus Compounds with Adamantane-like Structure. VII. Preparation and Properties of Nonathio CyclotriphosphateReaction of both, P4S10 and P4S9, in liquid ammonia below -33°C yields ammonium nonathio cyclotriphosphate, (NH4)3[P3S9] (I), which crystallizes on cooling to -78°C. On ammonolytic decomposition of I trithio amidophosphate, (NH4)2[PS3(NH2)], is obtained. I reacts with PCl3 re-building the adamantane-like structure of P4S9. Further properties and reactions of I are described.
    Notes: Die Reaktion von P4S10 oder P4S9 mit flüssigem Ammoniak führt unterhalb -33°C zu Ammoniumnonathiocyclotriphosphat, (NH4)3[P3S9] (I), das beim Abkühlen auf -78°C auskristallisiert. Bei der ammonolytischen Spaltung von I entsteht Amidotrithiophosphat, (NH4)2[PS3(NH2)]. Mit PCl3 reagiert I unter Rückbildung der Adamantanstruktur des P4S9. Weitere Eigenschaften und Reaktionen von I werden beschrieben.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19824940106
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  • 9
    Electronic Resource
    Electronic Resource
    Hydrolyse- und Kondensationsreaktionen im System Phosphoroxidbromid-WasserProfessor Günther Rienäcker zum 60. Geburtstage gewidmet (1964)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 329 (1964), S. 56-67 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The existence of dibromophosphoric acid formed by hydrolysis of phosphoryl bromide in acetone-Water mixtures has been proved by titration and by precipitation of the nitron salt. By condensation of partially hydrolyzed phosphoryl bromide, mixtures of polyphosphoric acids are formed. The end groups of these acids are supposed to be substituted by bromine atoms.
    Notes: Die Existenz der bei der Hydrolyse des Phosphoroxidbromids in Aceton-Wasser-Gemischen gebildeten Dibromophosphorsäure wurde titrimetrisch und durch Fällung des Nitronsalzes bewiesen. Durch Kondensationsreaktionen des partiell hydrolysierten Phosphoroxidbromids entstehen Gemische von Polyphorsäuren, deren Endgruppen wahrscheinlich durch Br-Atome substituiert sind.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19643290109
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  • 10
    Electronic Resource
    Electronic Resource
    Salze von Halogenophosphorsäuren. V. Darstellung und Struktur des Bis(äthylacetat)-calcium-difluorophosphates Ca[PO2F2]2 · 2 CH3COOC2H5 (1969)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 365 (1969), S. 294-300 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The preparation of bis(ethylacetate)-calcium-difluorophosphate is described. As shown by X-ray single crystal investigations, this compound belongs to the class of coordination polymers having a chain-like double-bridge structure.
    Notes: Die Darstellung des Bis(äthylacetat)-calcium-difluorophosphates Ca[PO2F2]2 · 2 CH3COOC2H5 wird beschrieben und durch röntgenographische Strukturuntersuchung nachgewiesen, daß diese Verbindung zur Gruppe der Koordinationspolymeren mit Doppelbrückenstruktur gehört.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19693650509
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