Synthesis of (E)-3'-phosphonoalkenyl modified nucleoside phosphonates via a highly stereoselective olefin cross-metathesis reaction

The synthesis of (E)-3'-phosphonoalkenyl and 3'-phosphonoalkyl modified nucleoside analogues with a β-D-erythrofuranose moiety is reported. The highly stereoselective olefin cross-metathesis reaction was applied to introduce the phosphonoalkenyl group at the 3'-position of the sugar moiety with absolute (E)-selectivity. The 3',6'-cyclomonophosphonic acids of 3'-phosphonoethyl-β-D-erythrofuranosyl nucleosides were synthesized via a dehydrative intramolecular cyclization reaction. None of the synthesized compounds shows significant in vitro activity against HIV, HCV, and RSV.