Abstract
We have used crude preparations of N-deoxyribosyl transferases (NdRT-II) from Lactobacillus helveticus to catalyze the transfer of a glycosyl moiety from a donor nucleoside to an acceptor base. Optimal conditions for the transglycosylation reaction to make D-D4FC starting from D-D4T and 5-FC were determined after the analysis of several experimental parameters including reaction time, concentration of substrate, pH and the type of buffer. For the first time, a practical procedure for enzymatic synthesis of β-D-2′,3′-unsaturated-5-fluorocytidine (β-D-2′,3′-didehydro-2′,3′-dideoxy-5-fluorocytidine, D-D4FC) from β-D-2′,3′-unsaturated thymidine (D-D4T) has been established. This method will be useful in the manufacture of important nucleoside analogues for anti-viral therapy.