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  • 1
    Electronic Resource
    Electronic Resource
    Preparation of trimethyl-2-hydroxyethylarsonium (arsenocholine) compounds (1987)
    New York, NY [u.a.] : Wiley-Blackwell
    Applied Organometallic Chemistry 1 (1987), S. 403-412 
    Details
    ISSN: 0268-2605
    Keywords: Trimethyl-2-hydroxyethylarsonium salts ; arsenocholine ; trimethyl-2-haloethylarsonium bromide ; trimethyl-2-acetoxyethylarsonium bromide ; acetylarsenocholine ; trimethyl-2-(dihydrogen phosphato)ethylarsonium bromide ; 1H and 13C NMR spectra ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Trimethyl-2-X-ethylarsonium salts (X=OH, Cl, Br, CH3COO; anion=Br) and trimethyl-2-diethoxyethylarsonium bromide were prepared from trimethylarsine and the appropriate organic bromides in sealed tubes at elevated temperatures or by refluxing the neat reagents. The yields ranged from 33 to 85%. Anion exchange reactions produced the arsonium iodides, nitrates, acetates, tosylates, tetraphenylborates, picrates, hydroxides, and carbonates. Arsenocholine bromide (X=OH) was phosphorylated with concentrated phosphoric acid. The product was isolated as the barium salt. Treatment of the barium salt with sulfuric acid yielded trimethyl-2-(dihydrogen phosphato)ethylarsonium bromide. These substances were synthesized to serve as precursors for arsenic- containing phospholipids and as standards for the chromatographic identification of arsenocholines. The synthesized compounds were characterized by elemental analyses and 1H and 13C NMR spectroscopy. The shifts of the arsenic compounds were compared with those of the corresponding nitrogen compounds and found to be sufficiently different to be used for the identification of these compounds in their mixtures.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aoc.590010504
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  • 2
    Electronic Resource
    Electronic Resource
    Reorientational dynamics and internal mobility of the mixed agonist-antagonist opioid narcotic cyclazocine by 13C NMR relaxation times (1993)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 31 (1993), S. 823-828 
    Details
    ISSN: 0749-1581
    Keywords: Cyclazocine ; 13CNMR ; Relaxation times ; Reorientational dynamics ; Internal mobility ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The motional behaviour of the mixed agonist-antagonist opioid narcotic cyclazocine (2-cyclopropylmethyl-2′-hydroxy-5,9-dimethyl-6,7-benzomorphan) as a cationic species (CLZH +) was analysed by 13C NMR spin-lattice relaxation times (T1). Both AM1 and MM2 theoretical calculations were performed to predict the preferred conformations and torsional energetics of CLZH+ in the vapour phase. The analysis of the experimental T1 data (in aqueous solution) was performed by using an analytical model to describe the overall and internal motions of the molecule. The best fit of the relaxation times allowed the detection, in the liquid phase, of effective solute-solvent interactions and the fully anisotropic diffusive process of the molecule. The motional parameters obtained indicated an increased retational anisotropy of CLZH+ on passing from the gas phase to the solution state. Different activation energies arising from separate solvation effects were found for the motion of the 10-Me and 11-Me groups. The fitted energies and transition energies matrix relative to the internal motion of the N-cyclopropylmethyl group indicated that the preferred conformational states are not isolated and that the overall and internal motions are of the same order of magnitude.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrc.1260310906
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  • 3
    Electronic Resource
    Electronic Resource
    1H and 13C NMR spectra of rac-2,3-bis(palmitoyloxy)propyl(2-trimethylarsonioethyl)phosphonate, an arsenic-containing phosphonolipid (1990)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 28 (1990), S. 856-861 
    Details
    ISSN: 0749-1581
    Keywords: Arsenolipid ; 2D NMR ; 1H and 13C NMR ; 31P arsenophosphonolipid ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The 1H (500 MHz), 13C (300 MHz) and 31P (202 MHz) NMR spectra of rac-2,3-bis(palmitoyloxy)propyl(2-trimethylarsonioethyl)phosphonate were recorded in CDCl3 (3 M) solution. Homonuclear 1H-1H and heteronuclear 13C-1H chemical shift correlation experiments (COSY) were performed. All resonances were assigned. The shifts of the arsenic-containing phosphonolipid were compared with the shifts of the N-containing phospholipids. The most significant shift differences were found for the groups directly bonded to arsenic. Spectral evidence was indicative of free rotation about the —CH2 —CH2 —bond in the arsenocholine fragment.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrc.1260281004
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