1794 5-Bromouracil 5-bromouracil is brominated derivative of uracil that acts as an antimetabolite or base analog, substituting for thymine in DNA. It can induce DNA mutations in the same way as 2-aminopurine. It is used mainly as an experimental mutagen, but its deoxyriboside derivative (5-bromo-2-deoxyuridine) is used to treat neoplasms. 5-bromouracil can be generated naturally, within the body, from uracil by either eosinophil peroxidase or myeloperoxidase. These enzymes preferentially brominate uracil at plasma concentrations of bromine and under moderately acidic conditions. 51-20-7 5802 C4H3BrN2O2 189.937790 White powder. 310°C 0.815 mg/mL [GUNTHER,FA et al. (1968)] Oral (L626) ; inhalation (L626) ; dermal (L626) Thymidine phosphorylase, a pyrimidine salvage enzyme, transforms 5-bromouracil to 5-bromodeoxyuridine, a mutagenic analogue of thymidine. Ultimately, 5-bromouracil acts on DNA. It induces a random DNA point mutation via base substitution. The base pair will change from an A-T to a G-C or from a G-C to an A-T after a number of replication cycles, depending on whether 5-BrU is within the DNA molecule or is an incoming base when it is enolized or ionized. 5-Bromouracil normally pairs with adenine. However, the proportion of 5-bromouracil in the enol tautomer is higher than that of thymine because the bromine atom is more electronegative than is a methyl group on the C-5 atom. Thus, the incorporation of 5-bromouracil is especially likely to cause altered base-pairing in a subsequent round of DNA replication. 5-bromouracil is metabolized into 5-bromodeoxyuridine via thymidine phosphorylase. (L626) LD50: 1700 mg/kg (Rat, Intraperitoneal); LD50 1400 mg/kg (Mouse, Intraperitoneal) (T14) Not listed by IARC. May cause heritable genetic damage. Laboratory chemical used as a mutagen in many mutagenesis experiments. 5-bromouracil is a mutagen (causes mutations) and a carcinogen. It can cause respiratory tract irritation if inhaled, skin irritation if it contacts the skin and eye irritation if it contacts the eyes. 5-bromouracil can cause hypermotility, diarrhea, weight loss and possibly death if large amounts are repeatedly ingested. EYES: irrigate opened eyes for several minutes under running water. INGESTION: do not induce vomiting. Rinse mouth with water (never give anything by mouth to an unconscious person). Seek immediate medical advice. SKIN: should be treated immediately by rinsing the affected parts in cold running water for at least 15 minutes, followed by thorough washing with soap and water. If necessary, the person should shower and change contaminated clothing and shoes, and then must seek medical attention. INHALATION: supply fresh air. If required provide artificial respiration. 2009-06-22T16:08:36Z 2026-04-04T02:36:24Z 20552 D001976 5-Bromouracil true BrC1=CNC(=O)NC1=O C4H3BrN2O2 InChI=1S/C4H3BrN2O2/c5-2-1-6-4(9)7-3(2)8/h1H,(H2,6,7,8,9) LQLQRFGHAALLLE-UHFFFAOYSA-N 190.983 189.937789997 Exogenous Solid CHEMBL144730 5597 CHEM001540 DTXSID2058758 NS00032236 5-bromo-1,2,3,4-tetrahydropyrimidine-2,4-dione