These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: The SO4-.-induced oxidation of 2'-deoxyuridine-5'-phosphate, uridine-5'-phosphate and thymidine-5'-phosphate. An ESR study in aqueous solution.
    Author: Hildenbrand K.
    Journal: Z Naturforsch C J Biosci; 1990; 45(1-2):47-58. PubMed ID: 2158784.
    Abstract:
    Reactions of photolytically generated SO4-. with 2'-deoxyuridine-5'-phosphate (5'-dUMP), uridine-5'-phosphate (5'-UMP) and thymidine-5'-phosphate (5'-dTUMP) were studied by ESR spectroscopy in aqueous solution under anoxic conditions. From 5'-dUMP and 5'-UMP the 5',5-cyclic phosphate-6-yl radicals 10 and 11 were generated (pH 2-11) whereas from 5'-dTMP at pH 3-8 the 5,6-dihydro-6-hydroxy-5-yl radical 14 and at pH 7-11 the 5-methylene-2'-deoxyuridine-5'-phosphate radical 15 was produced. In the experiments with 5'-UMP in addition to radical 11 the signals of sugar radicals 12 and 13 were detected. It is assumed that the base radical cations act as intermediates in the SO4-.-induced radical reactions. The 5'-phosphate group adds intramolecularly to the C(5)-C(6) bond of the uraclilyl radical cation whereas the thymidyl radical cation of 5'-dTMP reacts with H2O at pH less than 8 to yield the 6-OH-5-yl adduct 14 and deprotonates at pH greater than 7 thus forming the allyl-type radical 15. In 5'-UMP transfer of the radical site from the base to the sugar moiety competes with intramolecular phosphate addition.
    [Abstract] [Full Text] [Related] [New Search]