5-substituted uridine derivatives

摘要

This invention provides a 5-substituted uridine derivative of the formula <IMAGE> wherein X is F or CF3, R1 and R2 each represent a group -OSi-(R4)(R5)(R6) (wherein R4, R5 and R6 represent C1-C10 alkyl or the like), OH, aminoacyloxy group wherein the amino group may be substituted with lower alkyl group or carboxylalkylcarbonyloxy group, R3 is a group -OSi(R4)(R5)(R6), H, OH, aminoacyloxy group wherein the amino group may be substituted with lower alkyl group, or carboxylalkylcarbonyloxy group, and at least one of R1, R2and R3 is a group -OSi-(R4)(R5)(R6), with the proviso that when X is fluorine atom, R3 is not hydrogen, and an intermediate for the preparation thereof, preparation processes of the derivative and anti-tumor agent containing the derivative as an active ingredient.