Phosphotriester method using polymer support

Three types of method are used for the chemical synthesis of oligodeoxyribo-nucleotides. The phosphodiester method, in which a nucleotide with a protected 5 -hydroxy group is condensed with a nucleoside-5 -monophosphate with a protected 3 -OH, has been extended by use of the polymer-support method analogous to that used for peptide synthesis. The phosphotriester method has been modified by Narang et al., to use a two-step coupling procedure starting with a nucleotide with a fully masked 3 -phosphate. The most recent type of... 

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