A dioxolane derivative and a novel L-configuration deoxycytidine analogue with potent antineoplastic activity. When incorporated into growing chain during DNA replication, troxacitabine stops DNA polymerization due to its unnatural L-configuration, in contrast to the normal nucleotides with D-configuration. As a result, this agent terminates DNA synthesis upon incorporated into DNA molecules, and consequently interrupts tumor cell proliferation. or A drug being studied for use as an anticancer agent.