IUPAC definition : 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').;
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').