| abstract |
The present invention provides lipids that are advantageously used in lipid particles for the in vivo delivery of therapeutic agents to cells. In particular, the invention formula (I) provides lipids having the following structure XXXIII wherein: R 1 and R 2 are each independently for each occurrence optionally substituted C 10 -C 30 alkyl, optionally substituted C 10 -C 30 alkenyl, optionally substituted C 10 -C 30 alkynyl, optionally substituted C 10 -C 30 acyl, or -linker-ligand; R 3 is H, optionally substituted C 1 -C 10 alkyl, optionally substituted C 2 -C 10 alkenyl, optionally substituted C 2 -C 10 alkynyl, alky Ihetro cycle, alkylphosphate, alkylphosphorothioate, alkylphosphorodithioate, alkylphosphonates, alkylamines, hydroxyalkyls, ω-aminoalkyls, ω-(substituted)aminoalkyls, ω-phosphoalkyls, ω-thiophosphoalkyls, optionally substituted polyethylene glycol (PEG, mw 100-40K), optionally substituted mPEG (mw 120-40K), heteroaryl, heterocycle, or linker-ligand; and E is C(O)O or OC(O). |