#$%^&*AU2016208436A120160818.pdf#####NOVEL LIPIDS AND COMPOSITIONS FOR THE DELIVERY OF THERAPEUTICS 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: R1 and R 2 are each independently for each occurrence optionally substituted Cio-C30 alkyl, optionally substituted Cio-C30 alkenyl, optionally substituted C10-C 30 alkynyl, optionally substituted C10 -C30 acyl, or -linker-ligand； R 3 is H, optionally substituted C1-Cio alkyl, optionally substituted C2-Cio alkenyl, optionally substituted C2 -Cio alkynyl, alky lhetro cycle, alkylphosphate, alkylphosphorothioate, alkylphosphorodithioate, alkylphosphonates, alkylamines, hydroxyalkyls, o-aminoalkyls, o(substituted)aminoalkyls, o-phosphoalkyls, o-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). R3-E- (R, (1) R2
