NOVEL NON-NUCLEOSIDIC BUILDING-BLOCKS FOR THE PREPARATION OF MULTILABELED OLIGONUCLEOTIDES

Synthesis of new non-nucleosidic phosphoramidites 1 and 2 derived from achiral precursors containing two reporter groups or amino functions is described. Among them, only phosphoramidites 1a-c allow multiple de rivatization of synthetic oligonucleotides. The usefulness of building blocks 1a-c is demonstrated by introduction of several amino function s or fluorescent dansyl reporters at the 3'- and 5'-termini of synthet ic oligonucleotides and their phosphorothioate analogues. It is demons trated that multilabeled non-nucleosidic tether has no or only minor i nfluence on the hybridization properties of the oligonucleotides.