Patent ID: 7553830

Claim:
A cationic lipid having the formula VII: R 6 -L 1 -Cholesterol wherein, R 6 is selected from the group consisting of arginyl methyl ester, arginyl amide, homoarginyl methyl ester, homoarginyl amide, ornithine methyl ester, ornithine amide, lysyl methyl ester, lysyl amide, triethylenetetramine (TREN), N,N′-di-carboxamidine TREN, N-benzyl histidyl methyl ester, pyridoxyl and aminopropylimidazole; and L 1 is a linker represented by R 7 PO2, wherein R 7 is H, CH 3 , or CH 2 CH 3 .