Collect. Czech. Chem. Commun. 1986, 51, 2285-2290

Inhibition of DNA-dependent DNA polymerase α by arabinosyl-5-azacytosine and its metabolic transformation in L1210 mouse leukemic cells

Jiří Veselý

Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, 166 10 Prague 6


Arabinosyl-5-azacytosine is phosphorylated by the L1210 mouse leukemic cells in vivo as well as by the cell-free extract in the presence of ATP. The drug inhibits in vitro the activity of DNA-dependent DNA polymerase α from L1210 cells in a dose-dependent manner but to a lesser degree than arabinosylcytosine. When administered in vivo, it depresses the activity of DNA polymerase to about the same extent as arabinosylcytosine. The Km constant for the phosphorylation of arabinosyl-5-azacytosine is 46% higher than the corresponding value for arabinosylcytosine.