5,6-Dihydro-5-Fluorouracil-13C,15N2 (5-DHFU-13C,15N2) is the 13C- and 15N-labeled labeled 5,6-Dihydro-5-Fluorouracil (HY-134160). 5,6-Dihydro-5-Fluorouracil (5-DHFU, 5-Fluorodihydropyrimidine-2,4-dione) is the active metabolite of the thymidylate synthase inhibitor prodrug 5-fluorouracil (HY-90006), which is formed from 5-fluorouracil by dihydropyrimidine dehydrogenase (DPD). 5,6-Dihydro-5-Fluorouracil is cytotoxic to HaCaT keratinocytes (IC50=13.5 µM). Intravenous administration of 5,6-Dihydro-5-Fluorouracil (90 mg/kg/wk) in combination with 5-fluorouracil and the DPD inhibitor eniluracil (HY-10533) slows tumor growth in a rat colon cancer model.
