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  • 1
    Electronic Resource
    Electronic Resource
    Solution structure of porphyrin aggregates determined by 1H NMR ring current shifts. I. Heterodimers of oppositely charged porphyrins (1987)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 25 (1987), S. 1069-1073 
    Details
    ISSN: 0749-1581
    Keywords: Ring current shifts ; Heterodimers of oppositely charged porphyrins ; Solution structure ; 1H NMR ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The solution structures of dimers consisting of negatively charged Zn[tetra(4-carboxyphenyl)porphyrin], ZnTPPC, with positively charged Zn[tetra(4-N-methylpyridyl)porphyrin], ZnTMPyP, and with H2[tetra(4-N-methylpyridyl)porphyrin], H2TMPyP, were determined by 1H NMR ring current shifts. The conformation is not affected by the presence of the metal in the centre of the TMPyP monomer. The dimers have a cofacial conformation with a plane-to-plane separation of 3.1 Å and an in-plane translation of 4.2 Å along the aryl - aryl axis.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrc.1260251210
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  • 2
    Electronic Resource
    Electronic Resource
    Solution structure of porphyrin aggregates determined by 1H NMR ring current shifts. II.For Part I. see Ref. 5. Conformations of dimers and higher aggregates of water-soluble porphyrins (1988)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 26 (1988), S. 167-172 
    Details
    ISSN: 0749-1581
    Keywords: Ring current shifts ; Aggregates of oppositely charged porphyrins ; Solution structure ; 1H NMR ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The aggregation of the water-soluble porphyrins tetra(4-carboxyphenyl)porphyrin free base (H2TPPC), tetra(4-N-methylpyridyl)porphyrin free base (H2TMPyP) and their zinc derivatives (ZnTPPC and ZnTMPyP) was studied by 1H NMR and optical absorption spectroscopy. In the solvent H2O—CH3OH (4:1), mixing of the anionic H2TPPC or ZnTPPC with the cationic H2TMPyP or ZnTMPyP yields various types of “hetero” aggregates. Only H2TPPC forms “homo” aggregates in this solvent. Addition of 1 m KCl results in an increase in the aggregation of H2TPPC and also enhances the aggregation of ZnTPPC. The structures of the “hetero” aggregates are stacks of the oppositely charged porphyrins in an alternating order. However, when one of the constituents is H2TPPC, aggregates having structures of the “homo” type are also formed. The 1H NMR ring current shifts are accounted for by identical conformations of dimers, and dimer structures in trimers and higher aggregates of the “hetero” type.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrc.1260260214
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  • 3
    Electronic Resource
    Electronic Resource
    High-field proton NMR study of the liquid solution structure of monomeric bacteriochlorophyll a and chlorophyll a (1987)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 25 (1987), S. 670-674 
    Details
    ISSN: 0749-1581
    Keywords: Chlorophylls ; 1H NMR ; Structure ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The 500 MHz proton spectra of monomeric bacteriochlorophyll a and chlorophyll a were recorded and assigned. The proton chemical shifts and proton-proton coupling constants were all determined except for the P-5 to P-15 phytyl side-chain protons. The conformational structures of the reduced rings and associated side-chains in these compounds were deduced from vicinal coupling constants. The reduced ring IV and the propionic ester side-chain in bacteriochlorophyll a and chlorophyll a have identical conformations which, in addition, are very similar to those reported previously for methyl pheophorbide a and pheophytin a. The reduced ring IV of bacteriochlorophyll a, which is attached to the phytyl side-chain, is more buckled than the other reduced ring (ring II).
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrc.1260250803
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