HPLC of 2′-deoxynucleoside-3′-N-dialkylamino-methoxyphosphanes (“Deoxynucleoside-3′-phosphoamidites”)

It was shown that HPLC under the conditions specified above is a valuable and reliable method for quantitative analysis of deoxynucleoside-phosphoamidites. As demonstrated the HPLC-procedure complements the well established31P-NMR-spectroscopy for the analysis of P-amidites. The corresponding data obtained by one method correlate with those obtained by the other. Beyond that the method gives additional information by detection of impurities absorbing at 254 nm. A further benefit of the method presented here is the separation of the P-diastereomer isomers, not necessarily required for the original analytical objective but certainly of theoretical interest. The higher stability of deoxynucleoside-phosphoamidites bearing the diisopropylamino-substituent rather than the dimethylamino-group observed before [2, 3] has now been verified on a quantitative basis by this new HPLC-procedure. Results are presented in Fig. 1.