What are nucleobases?

Some articles on nucleobases:

Nucleobase
... Nucleobases are a group of nitrogen-based molecules that are required to form nucleotides, the basic building blocks of DNA and RNA ... Nucleobases provide the molecular structure necessary for the hydrogen bonding of complementary DNA and RNA strands, and are key components in the formation of stable DNA and RNA molecules ... Nucleobases (or nucleotide bases/nitrogenous bases/aglycones) provide the nucleotide structure necessary to form base pairs ...
Deoxyribonucleic Acid
... phosphate groups (related to phosphoric acid), with the nucleobases (G, A, T, C) attached to the sugars ... sugar is one of four types of molecules called nucleobases (informally, bases) ... It is the sequence of these four nucleobases along the backbone that encodes information ...
Nucleic Acid Analogues - Base Analogues - Metal Base-pairs
... DNA can occur by the formation of non-canonical base pairs from natural nucleobases with participation by metal ions and also by the exchanging the hydrogen atoms that are ... Metal complexing has been shown to occur between natural nucleobases ... A well-documented example is the formation of T-Hg-T, which involves two deprotonated thymine nucleobases that are brought together by Hg2+ and forms a connected metal-base pair ...