Phosphoramidate Analogs of Dinucleotides: Synthesis and1H Assignment by Two Dimensional NMR Spectroscopy (1H,1H-COSY)

The synthesis of several dinucleoside phosphate derivatives which are linked by phosphoramidate bonds 3′-OP(O)NH-5′ are described. One of these dimer units can be used in automated solid phase DNA synthesis by the phosphoramidite procedure. In order to study the conformational change which is induced on substituting O-P-0 against O-P-N we have also p-repared the fully deprotected dimer analog. The constitution of the dimer units were confirmed by means of 2D-300MHZ homonuclear chemical shift correlation spectroscopy (1H,1H-COSY).