C-Glycoside phosphoramidite building block for versatile functionalization of oligodeoxyribonucleotides

Abstract

A chiral non-nucleosidic phosphoramidite building block containing a thioester function in its structure, 4, is synthesized in six steps starting from ‘2-deoxy-D-ribose’. It is used in the machine-assisted oligonucleotide synthesis in a conventional manner. Upon completion of the oligonucleotide chain assembly the thioester bond is cleaved with various nucleophiles (hydroxide ion, propane-1,3-diamine, cystamine, histamine), resulting in oligonucleotide conjugates with a tether group in the middle of the oligonucleotide chain.