| Autor: |
J. Moiroux, M. A. Schwaller, Jean Aubard, Georges Lévi, S. Bernard, E. A. Bazzaoui |
| Rok vydání: |
1996 |
| Předmět: |
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| Zdroj: |
Journal of Raman Spectroscopy. 27:539-547 |
| ISSN: |
0377-0486 |
| DOI: |
10.1002/(sici)1097-4555(199607)27:7<539::aid-jrs999>3.0.co;2-o |
| Popis: |
Oxidative transformations of 9-hydroxyellipticine (9-OH-E) andN2-methyl-9-hydroxyellipticinium (NMHE) were performed in aqueous solutions. Electrochemical oxidation of 9-OH-E and biochemical and chemical oxidation of NMHE, were monitored by UV–visible absorption and their reaction products characterized by surface-enhanced Raman scattering (SERS). Spectroscopic analyses of the oxidation product obtained from the 2e− electrochemical process of 9-OH-E at Pt and Ag electrodes permitted the identification of the quinone-imine function. Comparison with the spectra of products resulting from the biooxidation of NMHE by the peroxidase–H2O2 system revealed the occurrence of the same reactive species. On the other hand, UV–visible and SERS analyses of the chemical oxidation of NMHE by sodium hypochlorite seem to indicate that this pathway is not efficient enough to generate such a primary quinone-imine oxidation species. In this case, only di-o-quinones were detected and identified as the main oxidation products. All the spectroscopic results of this study confirm the crucial role of the electrophilic quinone-imine function in the bio-oxidative metabolic transformation which leads to covalent adducts by trapping biological nucleophiles. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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