Novel non-nucleosidic phosphoramidite building blocks for versatile functionalization of oligonucleotides at primary hydroxy groups

Abstract

Synthesis of two non-nucleosidic phosphoramidite building blocks, 1a, b, that enable attachment of various tether groups to oligonucleotides at their 5′-terminus (or 1′-OH of 3′-deoxypsiconucleoside units) is described. Introduction of these linkers during the oligonucleotide assembly on a solid support, and their subsequent derivatization upon deprotection, afforded amino-, carboxy-, and sulfanyl-alkyl-tethered oligonucleotides.