We recently took advantage of the fact that guanosine derivatives become highly soluble in aqueous solution when dissolved in alkali, owing to the removal of the N-1 proton. We have used this approach to facilitate the synthesis of thiophosphate derivative 2a through solubilisation of iodoguanosine starting material 1a. To improve the kinetics of the bimolecular displacement process, a large excess of thiophosphatenucleophile was used and initial concentrations of both reagent ...
