C-Alkenylation of pyrimidine nucleosides and their analogues

Methods for C-alkenylation of heterocycle moieties of pyrimidine nucleosides and their analogues are generalised. The methods employing both organoelement nucleoside derivatives (organomercury, -tin, -boron and -lithium) and organoelement alkene derivatives (organomagnesium, -boron, -aluminium, -tin and -silicon) as well as palladium-catalysed oxidative coupling and photochemical reactions are considered. The reaction conditions (the role of solvents, catalysts and co-catalysts, temperature and time modes) are discussed. The advantages and the drawbacks of different approaches for introduction of alkenyl groups are discussed. Examples of practical applications of alkenylated nucleoside derivatives and their analogues are given. The bibliography includes 92 references.