5-Fluorouracil

Thymidylate synthase inhibitor / 5-Fluorouracil (5-FU) is a clinically useful anticancer agent that acts via irreversible inhibition of thymidylate synthase. The active metabolites of 5-FU are 5-Fluorodeoxyuridylate (5-FdUMP), 5-Fluorodeoxyuridine triphosphate (5-FdUTP) and 5-Fluorouridine triphosphate (5-FUTP). The primary cytotoxic effect of 5-FU is believed to be inhibition of thymidylate synthase by 5-FdUMP. Secondary effects include incorporation of 5-FdUTP into DNA resulting in DNA strand breaks and incorporation of 5-FUTP into RNA causing abnormal RNA processing.1