L-I-OddU, a L-5'-halo- dioxolane nucleoside analogue, is a potent and selective anti-Epstein-Barr virus (EBV) agent with an EC50 value of 0.03μM. L-I-OddU has low cytotoxicity with a CC50 value of 1000 nM. L-I-OddU has antiviral activity by suppressing replicative EBV DNA and viral protein synthesis[1][2].