Abstract: Disclosed are novel bifunctional nucleoside analogs and oligonucleosides of 3-4 bases (trimers and tetramers) and longer containing at least two consecutive internucleoside linkages of two carbon-one nitrogen atom or two carbon-one oxygen atom (3'-NCC-5', 3'-CNC-5', 3'-OCC-5') internucleoside linkages. The bifunctional nucleosides are useful for preparing the trimers and tetramers, which, in turn, are useful, together with the nucleosides, in preparing oligonucleosides as well as chimeric oligonucleotide analogs, preferably antisense oligonucleosides and oligonucleotide analogs, of 6 to about 60 bases having at least two consecutive internucleoside linkages of two carbon atoms and one nitrogen atom or 2 carbon atoms and one oxygen atom in the oligonucleoside backbone.

Abstract: The present invention relates to compounds, compositions and methods for inhibiting gene expression. The compounds of this invention comprise 1) oligonucleoside sequences of from about 6 to about 200 bases having a three atom internucleoside linkage or 2) oligonucleotide sequences of from about 9 to about 200 bases having a diol at either or both termini.

Abstract: Disclosed are oligonucleotide analogs comprising oligonucleoside sequences having from 3 to about 200 bases and containing internucleoside linkages wherein amide linkages replace phosphodiester linkages that are the backbones of the natural oligonucleotides that make up RNA and DNA. Also disclosed are bifunctional nucleoside analogs, a process for preparing dimers and trimers therefrom, and a method of using these bifunctional nucleoside intermediates, including the dimers and trimers, to synthesize the above-described oligonucleotide analogs using conventional synthetic organic procedures known in the art, preferably in a solid phase synthesis, more preferably in an automated peptide synthesizer.