Synthesis of 2′-O,3′-C-linked bicyclic nucleosides and bicyclic oligonucleotides

Abstract

The 3′-C-allyl furanose 4 has been used as a precursor for synthesis of the novel 2′-O,3′-C-linked bicyclic thymine nucleosides 15, 16, 20 and 25. The three bicyclic β-nucleosides 15, 20 and 25 have been incorporated into oligodeoxynucleotides. One of these nucleosides, dioxabicyclo[3.3.0]octane derivative 25, induces increased thermal stability of duplexes towards complementary RNA.