       Document 0054
 DOCN  M9590054
 TI    [Reactions of 5'-H-phosphonates, 5'-F-phosphates, and 5'-phosphates of
       modified thymidines in human blood plasma]
 DT    9509
 AU    Kuznetsova EV; Kukhanova MK; Arzumanov AA; Kraevskii AA
 SO    Mol Biol (Mosk). 1995 Mar-Apr;29(2):415-20. Unique Identifier : AIDSLINE
       MED/95303108
 AB    Mechanisms and rates of hydrolytic dephosphorylation of 5'-hydrogen
       phosphonates, 5'-fluorophosphates, and 5'-phosphates of
       3'-azido-3'-deoxythymidine, 3'-fluoro-3'-deoxythymidine, and thymidine
       in human blood serum were investigated. 5'-Hydrogen phosphonates of
       3'-substituted thymidines are dephosphorylated 50-100 times slower than
       the corresponding 5'-phosphates. 5'-fluorophosphates of 3'-substituted
       thymidines are dephosphorylated 2 times slower than corresponding
       5'-phosphates; first, substituted thymidine 5'-phosphates are formed,
       which are later dephosphorylated into substituted thymidines. These data
       illustrate probable molecular mechanisms of anti-HIV action of such
       nucleotides. 5'-hydrogen phosphonates of thymidines can serve as depot
       forms of corresponding thymidines, but other metabolic pathways are not
       excluded. Thymidine 5'-fluorophosphates can serve as depot-forms of both
       thymidines and their phosphates. Their fate in cells depends probably on
       their diffusion and on the activities of dephosphorylating and
       phosphorylating enzymes.
 DE    English Abstract  Fluorine/CHEMISTRY  Human  Hydrogen/CHEMISTRY
       Hydrolysis  Kinetics  Phosphates/BLOOD/*CHEMISTRY  Phosphonic
       Acids/BLOOD/*CHEMISTRY  Phosphorylation  Thymidine/BLOOD/*CHEMISTRY
       JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

