Tags: Chemical Compound, Chemical Substance.
Cytosine /ˈsaɪtɵsɨn/ (C) is one of the four main bases found in DNA and RNA along with adenine guanine and thymine (uracil in RNA). It is a pyrimidine derivative with a heterocyclic aromatic ring and two substituents attached (an amine group at position 4 and a keto group at position 2). The nucleoside of cytosine is cytidine. In Watson-Crick base pairing it forms three hydrogen bonds with guanine.
