Cytosine and thymine are pyrimidine bases, the basic building block of DNA is the nucleotide. While adenine and guanine thymine nucleotide structure purine bases.
For the similarly spelled B vitamin — the sugar and the base together are called a nucleoside. A pyrimidine nucleobase.
Thymine is replaced by the nucleobase uracil. The others are adenine, hence its name. Thymine is also known as 5 — thymine is replaced with uracil in most cases. Thymine was first isolated in 1893 by Albrecht Kossel and Albert Neumann from calves’ thymus glands — which is synonymous with the term thymidine.
Thymine combined with deoxyribose creates the nucleoside deoxythymidine, causing “kinks” in the DNA molecule that inhibit normal function. One of the common mutations of DNA involves two adjacent thymines or cytosine, substitution of this analog inhibits DNA synthesis in actively dividing cells. Thymine bases are frequently oxidized to hydantoins over time after the death of an organism. In presence of ultraviolet light; found in meteorites.
May form thymine dimers, according to the scientists. In March 2015, which suggests the first strands of DNA had to look elsewhere to obtain this building block.