has role has role has functional parent independent continuant radiosensitizing agent uracil antimetabolite antineoplastic agent xenobiotic immunosuppressive agent organofluorine compound 5-fluorouracil Fluorouracil 5-FU CHEBI:46345 5-Fluoracil CHEBI:46343 A nucleobase analogue that is uracil in which the hydrogen at position 5 is replaced by fluorine. It is an antineoplastic agent which acts as an antimetabolite - following conversion to the active deoxynucleotide, it inhibits DNA synthesis (by blocking the conversion of deoxyuridylic acid to thymidylic acid by the cellular enzyme thymidylate synthetase) and so slows tumour growth. CHEBI:2054 5-Fluoropyrimidine-2,4-dione chebi_ontology 5-Fluorouracil 5-Fluorouracil nucleobase analogue environmental contaminant