Lipase-catalyzed regioselective synthesis of lipophilic inosine ester derivatives

Enzymatic synthesis of fatty acid inosine esters was performed by the immobilized lipase from Mucor miehei (Lipozyme®)-catalyzed transesterification reaction of inosine and vinyl fatty acid esters (from vinyl caprylate to vinyl stearate) in acetone. Inosine was regioselectivly acylated at the primary hydroxyl groups and inosine derivatives with long chain acyl group were prepared in good yields. Reaction conditions including enzyme resources and solvents for the esterification were examined. The obtained 5′-O-acyl derivatives are more lipophilic than the parent inosine and thus suitable for potentially pharmaceutical application.