2amino6oxopurine

2-amino-6-oxopurine, commonly known as guanine, is one of the four main nucleobases found in DNA and RNA. It is a purine derivative in which an exocyclic amino group is attached at the C2 position and a carbonyl group occupies the C6 position of the bicyclic purine ring.

Guanine participates in canonical Watson-Crick base pairing with cytosine in nucleic acids. This pairing involves three hydrogen bonds, contributing to the stability of the DNA double helix and to proper base-pairing during replication and transcription. Chemically, guanine is a bicyclic heteroaromatic compound that can exhibit tautomeric forms, with the 2-amino-6-oxo form being the predominant structure under physiological conditions.

Biologically, guanine is synthesized and incorporated into nucleic acids as part of nucleotide metabolism. It also occurs in energy and signaling molecules, such as guanosine triphosphate (GTP), which plays roles in protein synthesis, signal transduction, and other cellular processes. In metabolism, guanine can undergo deamination to xanthine under certain conditions.

Guanine is not a separate therapeutic agent but its nucleosides and nucleotides are central to biochemistry and molecular biology. It is universally present in genetic material across organisms and is essential for the encoding of genetic information and for various RNA-based functions.

See also: adenine, cytosine, thymine, uracil, xanthine, purine.