Figure 1.

Schematic representation of the biological mechanism of action of fluoropyrimidine. FC = 5-fluorocytosine; FU = 5-fluorouracil; FUR = 5-fluorouridine; FUMP = 5-fluoro-5 monophosphate; FdUMP = 5-fluoro-2 deoxy-5 monophosphate; FUDP = 5-fluorouridine-5 diphosphate; FUTP = 5-fluorouridine-5 triphosphate; FdUDP = 5-fluorodeoxyuridine-5 diphosphate; FdUTP = 5-fluorodeoxyuridine-5 triphosphate; dUMP = deoxyuridin-5 monophosphate; dTMP = deoxythymidine-5 monophosphate; dTTP = deoxythymidine-5 triphosphate. Modified from the report of Lee et al.⁴²