Site of H Atom Attack on Uracil and Its Derivatives in Aqueous Solution

Suresh Das, David J. Deeble, Clemens von Sonntag
1985 Zeitschrift für Naturforschung C - A Journal of Biosciences  
Hydrogen atoms from the radiolysis of water at pH 1.6 add to the 5,6-double bond of pyrimidines. The preferen­tial site of attack is the C(5) position (values in brackets) in the case of 6-methyluracil (87%), 1,3-dimethyluracil (71%), uracil (69%) and poly(U) (60%). This reaction yields a radical of reducing properties which can be monitored by its reaction with tetranitromethane in a pulse radiolysis experiment. In thymine (37%), thymidine (32%) and 1,3-dimethylthymine (25%) H-addition no
more » ... r pre­ferentially occurs at C(5), but addition is now mainly at C(6). Hydrogen abstraction from the methyl groups or the sugar moiety is negligible (≦ 5.5%). A comparison is made with literature values for the equivalent reactions of OH radicals.
doi:10.1515/znc-1985-3-425 fatcat:5ozg642btzfmnevrsic37bva6y