A 2'-O-THIOL TETHER IN THE RIBOSE MOIETY OF NUCLEIC-ACIDS FOR CONJUGATION CHEMISTRY

A 2'-0-hexylthiotrityl adenosine phosphoramidite has been synthesized and incorporated into oligodeoxyribonucleotide (oligo) phosphodiesters and phosphorothioates. These oligos possess the lipophilic 2'-0-hexyl thiotrityl group at pre-selected positions. Upon treatment with silver nitrate solution, a free thiol group was generated which was further functionalized. The new tether offers a convenient nucleophile for con jugation of various pendant moieties that would reside in the minor gr oove. Because of its versatility and location, the modification has a variety of potential applications, most notably as an enhancer of anti sense activity.