FIRST SYNTHESIS OF FULLY DEPROTECTED DIIMIDOTRIPHOSPHORIC ACID AND DERIVATIVES DESIGNED FOR THE SYNTHESIS OF PNPNP NUCLEOTIDES AND DINUCLEOTIDES

The first synthesis of fully deprotected diimidotriphosphoric acid is described. The PNPNP sequence is obtained from an all protected cyclic precursor that can be regioselectively mono- or bis-functionalized wi th alcohols and amines in classical organic solvents. All protective g roups can be removed at the end of the synthesis by catalytic hydrogen ation to afford the corresponding PNPNP derivatives as a salt. The str ategy developed allows a straightforward access to a new class of nucl eotide and dinucleotide analogs as well as other triphosphorylated com pounds of biological relevance.