Materials for the delivery of biologically-active material to cells

1. A lipid of general formula (I) or (II):

wherein

X 1 and X 2 are —O—;

R 1 and R 2 for formula I are the same or different and are straight or branched, saturated or unsaturated C 7 to C 24 hydrocarbyl groups which are unsubstituted or substituted by one or more substituents selected from the group consisting of hydroxy, halogen and OR′, wherein R′ is a C 1 to C 6 hydrocarbyl group and

R 1 and R 2 for formula II are the same or different and are straight or branched unsaturated C 7 to C 24 hydrocarbyl groups or straight or branched saturated C 18 to C 24 hydrocarbyl groups, which are unsubstituted or substituted by one or more substituents selected from the group consisting of hydroxy, halogen and OR′, wherein R′ is a C 1 to C 6 hydrocarbyl group;

R 5 is —N + (R 3 ) 2 —R 6 ;

R 6 is either:

(a) -[A-Y] n R 4 wherein:

each Y is the same or different and is —N + (R 4 ) 2 —;

each A is the same or different and is a C 1-20 alkylene group which is unsubstituted or substituted by one or more substituents selected from the group consisting of hydroxy, halogen, —OR′, —C(O)OH, —CN, —NR′R″, and —C(O)R′ wherein R′ and R″ are the same or different and are C 1-6 hydrocarbyl; and

n is an integer of from 1 to 10; or

(b) —[B—O] m B-Q wherein:

each B is the same or different and is a C 1-10 alkylene group which is unsubstituted or substituted by one or more substituents selected from the group consisting of hydroxy, halogen, —OR′, —C(O)OH, —CN, —NR′R″ and —C(O)R′ wherein R′ and R″ are the same or different and are C 1-6 hydrocarbyl;

m is an integer of from 1 to 10; and

Q is selected from the group consisting of —N + (R 3 ) 3 , —OH, —OR′, —OC(O)R′ and halogen, wherein R′ is as defined above; and

each R 3 and each R 4 is the same or different and is a straight or branched, saturated or unsaturated C 1 to C 10 hydrocarbyl group which is unsubstituted or substituted by one or more substituents selected from the group consist of hydroxy, halogen, —OR′, —C(O)OH, —CN, —NR′R″, and —C(O)R′ wherein R′ and R″ are the same or different and are C 1 to C 6 hydrocarbyl.

2. A lipid according to claim 1 wherein R 1 and R 2 are the same or different and represent a C 12-20 hydrocarbyl group.

3. A lipid according to claim 2 wherein R 1 and R 2 are the same or different and represent a C 14 , C 16 , C 18 or C 20 alkenyl group having one, two or three double bonds.

4. A lipid according to claim 3 wherein R 1 and R 2 are both C 16 or C 18 alkenyl groups having one double bond.

5. A lipid according to claim 1 wherein R 5 is —N + (R 3 ) 2 —R 5 and R 6 is —[B—O] m B-Q,

wherein:

each B is the same or different and is a C 1-6 alkylene group which is unsubstituted or substituted by one or more substituents selected from the group consisting of hydroxy, halogen, —OR′, —C(O)OH, —CN, —NR′R″ and —C(O)R′ wherein R′ and R″ are the same or different and are C 1-4 hydrocarbyl;

m is an integer of from 1 to 8; and

Q is selected from the group consisting of —N + (R 3 ) 3 , —OH and —OR′ wherein R′ is a C 1-4 alkyl group.

6. A lipid according to claim 1 , having the general formula (III):

wherein

R 1 and R 2 are the same or different and are straight or branched, saturated or unsaturated C 12-20 hydrocarbyl groups which are unsubstituted or substituted by one or more substituents selected from the group consisting of hydroxy, halogen and —OR′ wherein R′ is a C 1-6 hydrocarbyl group;

each R 3 is the same or different and is a straight or branched, saturated or unsaturated C 1-6 hydrocarbyl group which is unsubstituted or substituted by one or more substituents selected from the group consisting of hydroxy, halogen, —OR′, —COOH, —CN, —NR′R″ and —COR′ wherein R′ and R″ are the same or different and are C 1-4 hydrocarbyl;

R 6 is —[B—O] m B-Q wherein each B is the same or different and is a C 1-6 alkylene group which is unsubstituted or substituted by one or more substituents selected from the group consisting of hydroxy, halogen, —OR′, —C(O)OH, —CN, —NR′R″ and —C(O)R′ wherein R′ and R″ are the same or different and are C 1-4 hydrocarbyl; m is an integer of from 1 to 8; and Q is selected from the group consisting of —N + (R 3 ) 3 , —OH, —OR′, —OC(O)R′ and halogen wherein R′ is as defined above.

7. A lipid according to claim 1 , having the general formula (IV):

wherein

R 1 and R 2 are the same or different and are selected from the group consisting of C 12-20 alkylene groups and C 12-20 alkenylene groups;

each R 3 is the same or different and is selected from unsubstituted C 1-4 alkyl groups;

each B is the same or different and is a C 1-6 alkylene group which is unsubstituted or substituted by one or more substituents selected from the group consisting of hydroxy, halogen, —OR′, —C(O)OH, —CN, —NR′R″ and —C(O)R′ wherein R′ and R″ are the same or different and are C 1-4 hydrocarbyl;

m is an integer from 3 to 8; and

Q is selected from the group consisting of —N + (R 3 ) 3 , —OH, and —OR′ wherein R′ is an unsubstituted C 1-4 alkyl group.

8. A lipid according to claim 7 wherein R 1 and R 2 are both C 12-20 alkenylene groups having one double bond each.

9. A lipid according to claim 7 wherein each R 3 group is a methyl or ethyl group.

10. A lipid according to claim 7 wherein each B is the same or different and is an unsubstituted C 1-3 alkylene group.

11. A lipid according to claim 7 wherein m is selected from the group consisting of 3, 4, 5, 6 and 7.

12. A lipid according to claim 7 wherein Q is —OH or —OR′ wherein R′ is an unsubstituted C 1-4 alkyl group.

13. A lipid according to claim 1 , selected from the group consisting of {2,3-Di-[(Z)-octadec-9-enyloxy]-propyl}-N-(2-{2-[2-(2-hydroxy-ethoxy)-ethoxy]-ethoxy}-ethyl)-N,N-dimethylammonium bromide; {2,3-Di-[(Z)-ocatadec-9-enyloxy]-propyl}-N-{2-[2-(2-{2-[2-(2-hydroxy-ethoxy)-ethoxy]-ethoxy}-ethoxy)-ethoxy]-ethyl}-N,N-dimethylammonium bromide; {2,3-Di-[(Z)-hexadec-11-enyloxy]-propyl}-N-(2-{2-[2-(2-hydroxy-ethoxy)-ethoxy]-ethoxy}-ethyl)-N,N-dimethylammonium bromide; {2,3-Di-[(Z)-hexadec-11-enyloxy]-propyl}-N-{2-[2-(2-{2-[2-(2-hydroxy-ethoxy)-ethoxy]-ethoxy}-ethoxy)-ethoxy]-ethyl}-N,N-dimethylammonium bromide; and 1,4-Di(trimethylammonium)-2,2-dioleoyloxy-butane, diiodide.

14. A complex suitable for delivery of a biologically-active material to a cell, which complex comprises a lipid according to claim 1 and a biologically-active material.

15. A complex according to claim 14 wherein the biologically-active material is a nucleic acid, a peptide or a small molecule.

16. A complex according to claim 15 wherein the nucleic acid is a DNA or RNA.

17. A complex according to claim 14 which further comprises an integrin-binding peptide.

18. A process for the preparation of a complex comprising a lipid and a biologically-active material, which process comprises the step of admixing (i) a lipid according to claim 1 and (ii) a biologically-active material.

19. A process according to claim 18 , wherein an integrin-binding peptide is admixed with said lipid and said biologically-active material.