The phosphorothioite method. Synthesis of deoxyoligonucleotides on polymer supports by using nucleoside phosphorothioites.

The development of a new method, which is called "the phosphorothioite method", for synthesizing deoxyoligonucleotides on polymer supports is described. Nucleoside phosphorothioites were easily prepared and readily activated by iodine or silver acetate. In the case of the use of iodine, the present method did not require the oxidation step, because it could be simultaneously performed during condensation and thereby the reaction time could be shorten. This method was applied successfully to the polymer support synthesis.