Книга: Pyrimidine: Pyrimidine, Heterocyclic Compound, Aromaticity, Organic Compound, Benzene, Pyridine, Isomer, Diazine, Nitrogen, Atom, Nucleobase, Nucleic Acid

High Quality Content by WIKIPEDIA articles! 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. In DNA and RNA, these bases form hydrogen bonds with their complementary purines. Thus the purines adenine (A) and guanine (G) pair up with the pyrimidines thymine (T) and cytosine (C), respectively. In RNA, the complement of A is U instead of T and the pairs that form are adenine:uracil and guanine:cytosine.