Novel dendritic macromolecules consisting of uracil units (LnU-OBn) with the numbers of the nucleobase layers (n) of 2–4 were synthesized; L3U-OBn and L4U-OBn both formed 1∶1 complexes with La3+, where the L4U-OBn–La3+ complex, in particular, was highly robust towards methanolysis.