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Thymine (Molecule of the Month for September 2019)

Nucleobase, DNA

Thymine is one of the four nucleobases in the nucleic acid of DNA that are represented by the letters GCAT. The others are adenine, guanine, and cytosine. Thymine is also known as 5-methyluracil, a pyrimidine nucleobase. In RNA, thymine is replaced by the nucleobase uracil. Thymine was first isolated in 1893 by Albrecht Kossel and Albert Neumann from calves' thymus glands, hence its name.

As its alternate name (5-methyluracil) suggests, thymine may be derived by methylation of uracil at the 5th carbon. In RNA, thymine is replaced with uracil in most cases. In DNA, thymine (T) binds to adenine (A) via two hydrogen bonds, thereby stabilizing the nucleic acid structures.

Adenine is one of the two purine nucleobases (the other being guanine) used in forming nucleotides of the nucleic acids. In DNA, adenine binds to thymine via two hydrogen bonds to assist in stabilizing the nucleic acid structures.

Formal Chemical Name (IUPAC)



Picture of Thymine 3D model

click on the picture of  Thymine above to interact
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Thymine structure
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Picture of Thymine

C5 H6 N2 O2

Update by Karl Harrison
(Molecule of the Month for September 2019 )

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