Novel low molecular weight cationic lipids for oligonucleotide delivery

A cationic lipid of Formula A:

• wherein:
• R1 and R2 are independently selected from H, (C1-C6)alkyl, heterocyclyl, and polyamine, wherein said alkyl, heterocyclyl and polyamine are optionally substituted with one to three substituents selected from R′, or R1 and R2 can be taken together with the nitrogen to which they are attached to form a monocyclic heterocycle with 4-7 members optionally containing, in addition to the nitrogen, one or two additional heteroatoms selected from N, O and S, said monocyclic heterocycle is optionally substituted with one to three substituents selected from R′;
• R3 is independently selected from H and (C1-C6)alkyl, said alkyl optionally substituted with one to three substituents selected from R′;
• R′ is independently selected from halogen, R″, OR″, SR″, CN, CO2R″ or CON(R″)2;
• R″ is independently selected from H and (C1-C6)alkyl, wherein said alkyl is optionally substituted with halogen and OH;
• n is 0, 1, 2, 3, 4 or 5;
• L1 is selected from straight chain C12-C24 alkenyl, wherein said alkenyl are optionally substituted with one or more substituents selected from R′;
• or alkyl selected from the following structure;
• and
• L2 is selected from C3-C9 alkyl and C3-C9 alkenyl;
• or any pharmaceutically acceptable salt or stereoisomer thereof.