Synthesis of Oligonucleotides Carrying Thiol Groups Using a Simple Reagent Derived from Threoninol

Oligonucleotides carrying thiol groups are useful intermediates for a remarkable number of applications involving nucleic acids. In this study, DNA oligonucleotides carrying <em>tert</em>-butylsulfanyl (<em>t</em>-BuS) protected thiol groups have been prepared. A building block derived from threoninol has been developed to introduce a thiol group at any predetemined position of an oligonucleotide. The resulting thiolated oligonucleotides have been used for the preparation of oligonucleotide conjugates and for the functionalization of gold nanoparticles using the reactivity of the thiol groups