Ribosyl or deoxyribosyl derivatives (rarely, other glycosyl
derivatives) of certain pyrimidine or
purine bases.
They are thus
glycosylamines
or N-glycosides
related to
nucleotides by the lack of
phosphorylation. It has also become customary to include among
nucleosides analogous substances in which the glycosyl group is
attached to carbon rather than nitrogen ('C-nucleosides').
PAC, 1995, 67, 1307
(Glossary of class names of organic compounds and reactivity intermediates based on
structure (IUPAC Recommendations 1995))
on page 1352