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  • 1
    Electronic Resource
    Electronic Resource
    Radioiodination of nicotine with specific activity high enough for mapping nicotinic acetylcholine receptors (1996)
    Springer
    European journal of nuclear medicine 23 (1996), S. 157-162 
    Details
    ISSN: 1619-7089
    Keywords: Radioiodination ; Brain imaging ; Receptor autoradiography ; Nicotinic acetylcholine receptors ; Neurotransmission
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A novel radiochemical method is presented to synthesize 5-[123I/125I/131I]-dl-nicotine by radioiodination of 5-bromonicotine. Radioiodination of the precursur 5-dl-bromonicotine was achieved using a copper (I)-assisted nucleophilic exchange reaction in the presence of reducing agent. The reaction conditions were optimized by varying pH, concentration of Sn(II) salt, ascorbic acid, Cu(I)chloride and reaction temperature. After purification by high-performance liquid chromatography the radiochemical purity of the product exceeded 98%, with a radiochemical yield of 55% and a specific activity ≥5 GBq/µmol. Specific binding of the iodinated nicotine was demonstrated in rat brain by autoradiography. The radioactivity from the specific structures was displaced by an excess of non-radioactive nicotine (10−3 M) withK D andB max of 13.1±7.8 nM and 22±2.7 fmol/mg protein and unspecific binding of about 40%. The in vivo distribution of 5-[131I]iodonicotine was determined in 20 female Wistar rats at various time intervals of 15 s to 90 min post injection (p.i.) by well counting and autoradiography. Brain activity peaked within 0.5 min p.i., and then showed a biexponential washout. Initially, activity within the cerebral cortex exceeded that of the cerebellum by a factor of 1.5–2.0. It was also increased in the striatum and thalamus. However, as soon as 15 min p.i. activity was almost homogeneously distributed. In conclusion, synthesis of 5-iodo-dl-nicotine (labelled with131I,125I or123I, respectively) with appropriately high specific activity for receptor studies was achieved and specific binding to nicotine receptors in rat brain was demonstrated; following intravenous injection, however, there is considerable unspecific binding, obviously due to highly flow-dependent tissue retention.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01731839
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  • 2
    Electronic Resource
    Electronic Resource
    Stereochemie der Umlagerungs- und Reduktionsprodukte von Epoxyfencholenderivaten (1999)
    Springer
    Monatshefte für Chemie 130 (1999), S. 341-354 
    Details
    ISSN: 1434-4475
    Keywords: Keywords. Equilibration; Fencholenic derivatives; Hydroboration/Oxidation; Reduction.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary.  Starting with fencholenic epoxides 8a,b and 11, investigations of the rearrangement to the corresponding ketones were carried out. Reduction of the isomeric ketones 12a,b and 13a,b afforded each diastereomeric alcohols 14, 16/17 and 15, 18/19. Diastereomeric alcohols could be obtained by reduction of 8a,b and 11 and by hydroboration/oxidation of the fencholenic compounds 7 and 22. The stereochemistry of the new compounds is described.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/PL00010216
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  • 3
    Electronic Resource
    Electronic Resource
    Darstellung und Reaktionenvon Oxidationsprodukten aus β-Campholenverbindungen (1999)
    Springer
    Monatshefte für Chemie 130 (1999), S. 809-817 
    Details
    ISSN: 1434-4475
    Keywords: Keywords. β-Campholenic compounds; Epoxidation; KMnO4 oxidation; Reduction of epoxides; Allylic alcohols.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary.  Whereas the synthesis of α-campholenic compounds starting from α-pinene has been well investigated, only few is known about β-campholenic compounds. We obtained compounds suitable as precursors for the functionalization of the side chain of the β-isomer of the sandalwood flavour Brahmanol®. Now we report about the synthesis and the rearrangement of various β-campholenic epoxides to allylic alcohols or a bicyclic γ-lactone and the synthesis of cyclohexenones from β-campholenic esters.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/PL00010262
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  • 4
    Electronic Resource
    Electronic Resource
    Synthese und Geruchseigenschaften von Apo- und Homocampholenverbindungen (1998)
    Springer
    Monatshefte für Chemie 129 (1998), S. 89-97 
    Details
    ISSN: 1434-4475
    Keywords: Keywords. Sandalwood odour; Apocampholenic aldehyde; 2-(2 ; 2 ; 3 ; 4-Tetramethylcyclopent-3-enyl)ethanal; Structure-odour relationship; Synthetic sandalwood odour compounds; Brahmanol type compounds.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary.  New substances of the brahmanol® type with special substitution at the five-membered ring are included in the study of the relationship between structure and odour of sandalwood fragrances. Apobrahmanol compounds 14 and 17 are obtained from myrtenal via apocampholenic aldehyde (12) and exert sandalwood odour. The homobrahmanol derivatives 10 and 11, synthesized from α-pinene via fencholenic aldehyde (1b), lack any sandalwood odour, although their structure is similar to other sandalwood odour compounds.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/PL00010108
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  • 5
    Electronic Resource
    Electronic Resource
    Riechstoffsynthesen mit Fencholenaldehyd (1989)
    Springer
    Monatshefte für Chemie 120 (1989), S. 547-559 
    Details
    ISSN: 1434-4475
    Keywords: Aldol condensation ; Fencholenic aldehyde ; Homofencholenic aldehyde ; Sandalwood aroma chemicals ; Woody odour
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary With respect to the molecular requirements on sandalwood aroma chemicals the synthesis of some derivatives of the title compound is described. The synthesis of the new homofencholenic aldehyde affords the connection of the 2,2,4-trimethylcyclopentenylsystem with a santalol analogous side chain by condensation with propionic aldehyde. In contrast to the sandalwood odour of α-compholenic derivatives the analogous fencholenic compounds possess only woody notes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00810841
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  • 6
    Electronic Resource
    Electronic Resource
    Preparation of unleaded Bi2Sr2Ca2Cu3O10 (1991)
    Weinheim : Wiley-Blackwell
    Advanced Materials 3 (1991), S. 488-491 
    Details
    ISSN: 0935-9648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/adma.19910031006
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  • 7
    Electronic Resource
    Electronic Resource
    Zur photometrischen Bestimmung kleiner Selenmengen (1987)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 327 (1987), S. 154-156 
    Details
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Selenium(IV) or selenium(VI) is reduced in hydrochloric acid solution by means of chromium(II) to hydrogen selenide, which is passed into alkaline [Fe(CN)6]3− solution in a stream of nitrogen to be oxidized there to selenium(IV). 6 mol of [Fe]CN6]4− are formed per 1 mol of selenium. The latter reacts with iron(III) in the presence of 1,10-phenanthroline or bathophenanthroline-disulphonic acid to their Fe(II) complexes. The extinction coefficient for the determination of selenium is 68030 or 135700 1 · mol−1 · cm−1, respectively.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00469809
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  • 8
    Electronic Resource
    Electronic Resource
    Zur Konfiguration der 1,3-Dichlor-2-methyl-1-propene (1983)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 116 (1983), S. 522-526 
    Details
    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 1,3-Dichloro-2-methyl-l-propenesDetermination of the configurations of 1,3-dichloro-2-methyl-1-propenes (1) was performed by 1H and 13C NMR spectroscopy using the isomer pairs of 1,3-dichloro-1-propenes (2), 1-chloro-2-methyl-1-propene-3-ols (3) and 1-chloro-1-propene-3-ols (4) as reference compounds. The chemical shifts, vicinal coupling constants, relative LIS value and NOE effects were in an unambiguous agreement with the (Z)-configuration of the lower-boiling isomer of 1.
    Notes: Die Konfigurationen von 1,3-Dichlor-2-methyl-1-propenen (1) werden mittels 1H- und 13C-NMR-Spektroskopie zugeordnet. Als Vergleichssubstanzen dienten die Isomeren von 1,3-Dichlor-1-propen (2), 1-Chlor-2-methyl-1-propen-3-ol (3) und 1-Chlor-1-propen-3-ol (4). Die chemischen Verschiebungen, vicinalen Kopplungskonstanten, relativen LIS-Werte und NOE-Effekte stehen mit der (Z)-Konfiguration des niedriger siedenden Isomeren von 1 eindeutig im Einklang.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19831160213
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  • 9
    Electronic Resource
    Electronic Resource
    Synthese, Struktur und Reaktionen von α-Campholenepoxiden (1993)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1993 (1993), S. 987-991 
    Details
    ISSN: 0170-2041
    Keywords: Sandalwood odour ; Epoxidation, stereocontrolled ; Campholenic derivatives ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis, Structure and Reactions of α-Campholenic EpoxidesThe epoxidation of α-campholenic compounds 3, 4 is described, besides the rearrangement of the epoxides 5 and 6 into the hydroxy-β-campholenic system 7, 8, the reduction to the tertiary alcohols 11a, 12a, the alkylation reaction to 11b and 12b and the conversion of 7 into the diketone 10 are reported. The stereochemistry and the odour of the new compounds are also described.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.1993199301157
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  • 10
    Electronic Resource
    Electronic Resource
    The phase equilibrium diagram of Bi2O3-SrO-CaO-CuO-A tool of processing the high- Tc superconducting bismuth-compounds (1991)
    Weinheim : Wiley-Blackwell
    Advanced Materials 3 (1991), S. 67-69 
    Details
    ISSN: 0935-9648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/adma.19910030114
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