Nucleosides

The nucleosides are formed by bonding a ribose  or a deoxyribose, a nitrogenous base, by a N-glycosidic linkage between the -OH of the 1' carbon of the pentose and an amino group of the nucleobase (nitrogen 1', if it is pyrimidine, or nitrogen 9' if it is a puric base).

To name the nucleosides, the ending-osine is added to the name of the puric base, or the ending -idine if the base is pyrimidine.

• Thus, the nucleosides with ribose are: adenosine, guanosine, cytidine, and uridine.
• In the case of nucleotides with deoxyribose, the prefix deoxy - is prepended: deoxyadenosine, deoxyguanosine, deoxycytidine and deoxythymidine.

Animation: Main functional groups.

By NEUROtiker (Own work) [Public domain], via Wikimedia Commons