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Thursday 25 August 2005

Definition: A nitrogen-containing, single-ring, basic compound (cf. nitrogenous base) that occurs in nucleic acids. The pyrimidines in DNA are cytosine and thymine. The pyrimidines in RNA are cytosine and uracil.

Pyrimidine is a heterocyclic aromatic organic compound similar to benzene and pyridine, containing two nitrogen atoms at positions 1 and 3 of the six-member ring. It is isomeric with two other forms of diazine.

Three nucleobases found in nucleic acids, namely cytosine, thymine, and uracil, are pyrimidine derivatives. In DNA and RNA, these bases form hydrogen bonds with their complementary purines.

See also

- nucleic acid synthesis
- pyrimidine pathways
- pyrimidine dimers


- Loffler M, Fairbanks LD, Zameitat E, Marinaki AM, Simmonds HA. Pyrimidine pathways in health and disease. Trends Mol Med. 2005 Aug 9; PMID: 16098809