Direct and facile syntheses of heterocyclic vinyl-C-nucleosides for recognition of inverted base pairs by DNA triple helix formation: first report by direct Wittig route.

The ability to recognize specific gene sequences canonically would allow precise means for genetic intervention. However, specific recognition of two of the four possible base pairs by triplex-forming oligonucleotides (TFO) as X.T-A and Y.C-G within a triplex currently remains elusive. A series of C1-vinyl nucleosides have been proposed, and their stability and specificity have been evaluated extensively by molecular dynamics simulation. Because most C-nucleoside syntheses extend through direct substitution at the C1-position, a more convenient strategy for their syntheses via a direct Wittig coupling is presented here.