5-Fluorouracil derivatives have been synthesized, in 41-84% yield, by the Lewis acid catalyzed condensation of 2, 4-bis (trimethylsilyl)-5-fluorouracil with N-acyl-2- methoxyazacycloalkanes; the latter have been prepared by anodic oxidation of either N- acylprolines and N-acylpipecolic acids in methanolic sodium methoxide or N- acylperhydroazepines and N-acylmorpholines in methanolic tetraethylammonium ...