摘要 |
<p>The present invention provides nuclease resistant 5'-dithio-modified oligonucleotides that are useful in nucleic acid therapeutics and diagnostics. The novel modified oligonucleotides have at least one 5'-dithioate linkage, wherein both the oxygen atom at the 5'-position (5'-bridging oxygen) and at least one of the non-bridging oxygen atoms of a naturally occurring phosphodiester linkage are independently replaced with a single sulfur atom. The invention also provides a polymer-supported method for making 5'-dithio-modified and 5'-thio-modified oligonucleotides as well as novel monomeric nucleoside and nucleotide intermediates useful in the synthetic method.</p> |