Polyamine derivatives

1. A compound of the formula:

wherein

n1, n2, n3, and n4 are independently 1, 2, 3, or 4;

X and X′ are independently a bond, oxygen, or nitrogen;

R 1 and R 2 are independently C 8 -C 25 hydrocarbon groups optionally containing from 1-4 double or triple bonds; and

T 1 and T 2 are independently hydrogen or a targeting ligand;

G 1 and G 2 are independently bond or a polymer moiety,

where at least one of T 1 and T 2 is a targeting ligand.

2. A compound according to claim 1 , wherein n1, n2, n3, and n4 are all 1, and both X and X′ are bonds.

3. A compound according to claim 1 , wherein R 1 and R 2 are independently C 8 -C 25 hydrocarbon groups containing 1 or 2 double bonds.

4. A compound according to claim 1 , wherein at least one of G 1 and G 2 is a polyoxyalkylene, polyvinylpyrrolidone, polyacrylamide, polydimethylacrylamide, polyvinyl alcohol, dextran, poly(L-glutamic acid), styrene maleic anhydride, poly-N-(2-hydroxypropyl)methacrylamide, or polydivinylether maleic anhydride.

5. A compound according to claim 4 , wherein the polymer comprises at least one linker group between polymer units.

6. A compound according to claim 5 , wherein the polymer is a polyoxyalkylene where the oxyalkylene groups are independently straight or branched chain polyoxyalkylene groups having from 2-5 carbon atoms in their repeating units.

7. A formulation comprising a compound of claim 1 and a molecule selected from the group consisting of:

(a) ribosomal RNA; antisense polynucleotides of RNA or DNA; ribozymes; siRNA; shRNA; miRNA; and polynucleotides of genomic DNA, cDNA, or mRNA that encode for a therapeutically useful protein;

(b) an aptamer; or

(c) proteins, peptides, cholesterol, hormones, small molecule pharmaceutical compounds, vitamins, and co-factors.

8. A method for in vivo delivery of a molecule, said method comprising administering to a mammalian subject a therapeutically effective amount of a formulation of claim 7 .