#$%^&*AU2019283906A120200116.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 R2 are each independently for each occurrence optionally substituted C10-C 3 0 alkyl, optionally substituted C10-C30 alkenyl, optionally substituted C1 0-C3 0 alkynyl, optionally substituted C 10 -C3 0 acyl, or -linker-ligand； R3 is H, optionally substituted C1 -Cio alkyl, optionally substituted C2-C10 alkenyl, optionally substituted C2-C1o 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
