Go toArchive
Browse byFacets
Bookbag ( 0 )
'Semiquinones' in keywords Facet   section ZfN Section B  [X]
Results  2 Items
Sorted by   
Publication Year
1986 (1)
1983 (1)
1Author    HartmutB. Stegmann, Klaus Stolze, Klaus SchelflerRequires cookie*
 Title    ESR-Untersuchungen des Adrenalon-Semichinons und analoger Verbindungen ESR-Investigations of Adrenalone-Semiquinones and Related Compounds  
 Abstract    The autoxidation of adrenalone and other 4-acyl-catecholamines in the presence of diorganothalliumhydroxide are investigated by ESR-spectroscopy. On the basis of the counterion splitting and the proton coupling constants as well as the g-values a semi-quinone structure was established. By comparing several monosubstituted o-benzosemi-quinones an increment system for the assignment of the different proton coupling constants was developed. The agreement between experimental and calculated values is good for all compounds investigated. Prolonged autoxidation of adrenalone yields a stable para-magnetic secondary product. 
  Reference    Z. Naturforsch. 38b, 243—247 (1983); eingegangen am 1. September 1982 
  Published    1983 
  Keywords    Adrenalone, Semiquinones, ESR Spectra 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0243.pdf 
 Identifier    ZNB-1983-38b-0243 
 Volume    38 
2Author    E. N. Esr, HartmutB. Stegmann, Klaus Stolze, Klaus SchefflerRequires cookie*
 Title    ESR-und ENDOR-Untersuchungen der Autoxidationsprodukte des Adrenalons und analoger Verbindungen Investigations of the A utoxidation Products of Adrenalone and Related Compounds  
 Abstract    The signs of the proton coupling constants of adrenalone sem iquinone and related compounds were determ ined by E N D O R and T R IP L E resonance studies, thereby verifying the increment system described in our previous paper [2], Com parison of the spin-distribution of several substi­ tuted acylcatechols showed the conform ational influence on the coupling constants due to mesomeric interaction of the carbonyl group with the arom atic 7r-system. A drenalone and other N -m onosubstituted catecholam ines showed rather stable secondary radi­ cals after the decay of the prim ary sem iquinone radical. They were identified as substituted dihydropyrazinium cation radicals after selective deuteration and comparison of their ESR-, EN D O R -and TRIPLE -resonance spectra with those of the non-deuterated species. They are formed by cyclic condensation of two molecules with subsequent oxidation. E in fü h ru n g 
  Reference    Z. Naturforsch. 41b, 776 (1986); eingegangen am 24. Januar 1986 
  Published    1986 
  Keywords    A drenalone, Semiquinones, ESR Spectra, E N D O R Spectra 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/41/ZNB-1986-41b-0776.pdf 
 Identifier    ZNB-1986-41b-0776 
 Volume    41