abstract |
The present invention provides iRNA agents comprising at least one subunit of the formula (I): wherein: A and B are each independently for each occurrence O, N(RN) or S; X and Y are each independently for each occurrence H, OH, a hydroxyl protecting group, a phosphate group, a phosphodiester group, an activated phosphate group, an activated phosphite group, a phosphoramidite, a solid support, -P(Z')(Z'')O-nucleoside, -P(Z')(Z'')O-oligonucleotide, a lipid, a PEG, a steroid, a lipophile, a polymer, -P(Z')(Z'')O-Linker-OP(Z''')(Z'''')O-oligonucleotide, a nucleotide, an oligonucleotide, -P(Z')(Z'')-formula (I), -P(Z')(Z'')- or -Linker-R; R is LG, -Linker-LG, or has the structure shown below: LG is independently for each occurrence a carbohydrate, e.g., monosaccharide, disaccharide, trisaccharide, tetrasaccharide, oligosaccharide, polysaccharide; RN is independently for each occurrence H, methyl, ethyl, propyl, isopropyl, butyl, or benzyl; and Z', Z'', Z''' and Z'''' are each independently for each occurrence O or S. |