Thymidine and stavudine molecules in reactions with low-energy electrons
| Autor: | R. V. Khatymov, P. V. Shchukin, Mars V. Muftakhov |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
chemistry.chemical_classification
Radiation Double bond 010308 nuclear & particles physics Electron capture Photochemistry 01 natural sciences 030218 nuclear medicine & medical imaging Nucleobase Ion 03 medical and health sciences 0302 clinical medicine chemistry 0103 physical sciences Moiety Molecule Nucleoside Bond cleavage |
| Zdroj: | Radiation Physics and Chemistry. 184:109464 |
| ISSN: | 0969-806X |
| DOI: | 10.1016/j.radphyschem.2021.109464 |
| Popis: | The negative ion formation and fragmentation processes in thymidine and stavudine were studied by means of resonant electron capture mass spectrometry in the electron energy range 0–14 eV. Stavudine is a nucleoside analog of thymidine, that differs from the latter by the presence of double bond in the deoxyribose moiety. In the energy range below 5 eV transient negative ions have been found to arise via shape resonances resulting in electron attachment into the empty π*-orbitals. The main fragmentation channels for molecular ions are the H-atom loss and N-glycosidic bond cleavage between sugar and a nucleobase moieties. The dissociative electron attachment cross sections for the fragment negative ions were measured. The structures for some observed anions and neutral counterparts were suggested basing on the thermochemical approach for dissociative reactions energy balance under the support of quantum chemical calculations. The processes of ion formation in thymidine were found to be similar to those revealed previously for deoxyuridine nucleoside. In contrast, very strong dissociative channel was found for stavudine yielding [M–R]– ions (where R is a sugar moiety) in the energy range |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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