Abstract
Phosphorylation of cytarabine has been achieved using inorganic cyclo—triphosphate (P3m) in aqueous solution. The optimum condition for the phosphorylation of cytarabine with P3m is cytarabine : P3m = 1 : 10, pH 12 and 25 °C. Cytarabine 5′–triphosphate, cytarabine 3′–triphosphate, and cytarabine 2′–triphosphate were synthesized with the total yield of more than 75%. The phosphorylated products of cytarabine were stable in neutral and alkaline solution. The reaction mechanism of cytarabine with P3m was discussed.