It is a base analogue and is structurally similar to dTMP, except that the methyl group of T is replaced by bromine on the fifth carbon atom. 5-BU can produce two tautomers, one ketone and one enol. The ketone formula can be paired with A and the enol formula can be paired with G complementation, so that when 5-BU is incorporated into DNA replication, it causes a base-switching mutation. Thus, 5-Bromouracil can convert AT to GC, causing genetic mutations.
The hydrogen at the 5th position of bromouracil is an artificial base analogue substituted for bromine. It has a similar activity to thymine in living organisms and is generally used as a tracking substance. Can be surrounded by DNA. However, due to the high density of the nucleic acids polymerized here, it has become possible to precipitate by ultracentrifugation. In addition, because the photosensitivity of this nucleic acid increases, it can be applied to the induction of selective destruction of cells and artificial mutations.

5-Bromouracil has a wide range of uses in the biomedical and pharmaceutical fields. It is often used as a raw material for dyes, reagents and drugs. It is also used in the synthesis of nucleosides, chemoprotective groups and aromatic compounds.