The title compound, C(19)H(19)N(3)O(7), is a thymidine derivative and serves as an inter-mediate in the synthesis of a (99m)Tc radiolabeled nucleoside analog. Inter-molecular O-H⋯O hydrogen bonding is observed between the hydr-oxy functionalities of the ribose unit themselves as well as between a hydr-oxy group and an O atom of the phthalimide group of an adjacent mol-ecule. The mol-ecules are stacked on top of each other in the direction of the a axis. The crystal packing is further stabilized by weak intra- and inter-molecular C-H⋯O hydrogen bonds. The absolute configuration of the compound is known from the synthesis.