5-Fluoro-Uracil-Derivate

This invention relates to a 5-fluorouracil derivative represented by the formula wherein R is a hydrogen atom or a specific acyl group, Z is a phenyl-lower alkoxy-lower alkyl group, thienyl-lower alkyl group optionally substituted with halogen atom on the thienyl ring, or a group wherein R and R are each a hydrogen atom, a specific acyl group, phenyl-lower alkyl group having a group ROCO- on the phenyl ring, or a group -(A)nB, R fix being a specific organic group, A being a lower alkylene group, n being 0 or 1, and B being a 5- or 6-membered unsaturated heterocyclic group having 1 to 4 hetero-atoms selected from nitrogen, oxygen and sulfur and optionally having a benzene ring, naphthalene ring or pyridine ring condensed therewith, with the proviso that when R is a hydrogen atom or acyl group, R is not a hydrogen atom or acyl group; to a process for preparing the same; to an anticancer composition comprising an effective amounts of the same; and to use of the same for preparation of an anticancer composition.