Patent ID: 7595304

Claim:
An oligonucleotide prodrug of the formula: X 1 -(L 2 ) n -(L 1 ) o -R 1 wherein: R 1 is a polyalkylene oxide; L 1 is a releasable linking moiety; L 2 is a selected bifuntional spacing group comprising from about 2 to about 10 carbon atoms; X 1 is a single or double stranded oligonucleotide residue wherein the oligonucleotide ranges in size from 10 to 1,000 nucleotides; n, and o are independently a positive integer; and provided that (o+n)≧2, wherein L 2 is selected from the group consisting of: —(CR 50′ R 51′ ) q′ Q′-, —(CR 52′ R 53′ ) r′ O(CR 50′ R 51′ ) q′ Q′-, —(CR 52′ R 53′ ) r′ (OCH 2 CH 2 )Q′-, and wherein Q′ is O, S or NH; R 50′-53′ are independently selected from the group consisting of hydrogen, C 1-6 alkyls, C 3-12 branched alkyls, C 3-8 cycloalkyls, aryls, C 1-6 heteroalkyls, C 1-6 alkoxy, phenoxy and C 1-6 heteroalkoxy; and q′ and r′ are each a positive integer.