Structural features and biological properties of naturalStructural features and biological properties of natural disaccharide nucleosides and related compounds are considered. disaccharide nucleosides and related compounds are considered. The main methods for the synthesis of these compounds are The main methods for the synthesis of these compounds are described and their advantages and disadvantages are discussed. described and their advantages and disadvantages are discussed. These methods include condensations of a protected disaccharide These methods include condensations of a protected disaccharide with a heterocyclic base or of a protected nucleoside with an with a heterocyclic base or of a protected nucleoside with an activated monosaccharide. The bibliography includes 172 refer-activated monosaccharide. The bibliography includes 172 references ences. .