Polyoxazolines with Inert Terminating Groups, Polyoxazolines Prepared from Protected Initiating Groups and Related Compounds

• US 20110123453A1
• Filed: 07/10/2009
• Published: 05/26/2011
• Est. Priority Date: 07/10/2008
• Status: Active Grant

• Current Assignee: Serina Therapeutics, Inc.
• Original Assignee: Serina Therapeutics, Inc.
• Inventors: Jordon, Rainer, Reif, Michael, Bentley, Michael David, Harris, J. Milton, Yoon, Kunsang
• Granted Patent: US 8,883,211 B2
• Time in Patent Office: Days
• US Class Current: 424/9.1
• CPC Class Codes: A61K 9/1272 with substantial amounts of non-phosphatidyl, i.e. non-acylglycerophosphate, surfactants as bilayer-forming substances, e.g. cationic lipids with cholesterol as the only non-phosphatidyl surfactant A61K9/127; lipids as modifying agent A61K47/543
• CPC Class Codes: C08G 73/0233 Polyamines derived from (poly)oxazolines, (poly)oxazines or having pendant acyl groups
• CPC Class Codes: C08L 79/02 Polyamines

Abstract

The present disclosure provides novel functional polyoxazoline derivatives prepared by terminating polyoxazoline polymerization with inert chemical groups. In addition, the present disclosure demonstrates the synthesis of novel electrophilic initiators with protected functional groups capable of initiating oxazoline polymerization and capable of surviving the conditions of polymerization. These initiators are used to synthesize the above inert-terminal polyoxazoline derivatives as well as other poly-oxazolines with active terminal groups. Furthermore, the present disclosure provides for polyoxazoline-lipid conjugates and liposomal compositions prepared using such polyoxazoline-lipid conjugates. Methods of using the foregoing to prepare conjugates with target molecules are also disclosed.

Claims

1. A monofunctional polyoxazoline derivative of the general structure:

X—

R′

—

POZ—

S—

R*

wherein;

POZ is a polyoxazoline polymer of the structure —

[N(COR₂)CH₂CH₂]_n

X is an active functional group or a group capable of being converted to an active functional group, the active functional group capable of forming a linkage with a binding partner on a target molecule;

R′

is a linking group;

R₂ is independently selected for each repeating unit of the polyoxazoline polymer from an unsubstituted or substituted alkyl, alkenyl, aralkyl or heterocycylalkyl group;

R* is an inert group selected from an unsubstituted or substituted alkyl, alkenyl, aralkyl or heterocycylalkyl group; and

n is an integer from 3-1000.

2. The monofunctional polyoxazoline derivative of claim 1, wherein X is an alkyne, an oxyamine, an aldehyde, a ketone, an acetal, a ketal, an ester, a carboxylic acid, an activated carboxylic acid, an active carbonate, a chloroformate, an alcohol, an azide, a hydrazide, an amine, a protected amine, a thiol, a vinyl sulfone, a maleimide or an orthopyridyl disulfide.

3. The monofunctional polyoxazoline derivative of claim 1, wherein R₂ is an inert group.

4. The monofunctional polyoxazoline derivative of claim 1, wherein R₂ and R* are each independently an unsubstituted alkyl group or an aralkyl.

5. The monofunctional polyoxazoline derivative of claim 1, wherein R₂ and R* are each independently a C₁-C₁₂ alkyl group.

6. The monofunctional polyoxazoline derivative of claim 1, wherein R₂ is methyl, ethyl, isopropyl or n-propyl.

7. The monofunctional polyoxazoline derivative of claim 1, wherein R* is —

(CH₂)_o—

C₆H₅ and o is an integer from 1-25.

8. The monofunctional polyoxazoline derivative of claim 1, wherein the active functional group is protected.

9. The monofunctional polyoxazoline derivative of claim 1, wherein the POZ has a polydispersity value of less than or equal to 1.2, less than or equal to 1.1 or less than or equal to 1.05.

10. A monofunctional polyoxazoline derivative of the general structure:

I′

—

{POZ_I—

POZ_II}^a—

S—

R*

wherein;

I′

is an inert group present at the initiator position;

POZ_I is a polyoxazoline polymer of the structure [N(CO—

R′

—

Z)CH₂CH₂]_m

POZ_II is a polyoxazoline polymer of the structure [N(COR₂)CH₂CH₂]_n

R′

is an optional linking group;

Z is an active functional group or a group capable of being converted to an active functional group, the active functional group capable of forming a linkage with a binding partner on a target molecule;

R₂ is independently selected for each repeating unit of the polyoxazoline polymer from an unsubstituted or substituted alkyl, alkenyl, aralkyl or heterocycylalkyl group;

R* is an inert group selected from an unsubstituted or substituted alkyl, alkenyl, aralkyl or heterocycylalkyl group;

n is an integer from 0-1000, provided that when n=0, then m is >

1;

m is an integer 1-1000; and

a is ran, which indicates a random copolymer, or block, which indicates a block copolymer.

11. The monofunctional polyoxazoline derivative of claim 10, wherein Z is an alkyne, an oxyamine, an aldehyde, a ketone, an acetal, a ketal, an ester, a carboxylic acid, an activated carboxylic acid, an active carbonate, a chloroformate, an alcohol, an azide, a hydrazide, an amine, a protected amine, a thiol, a vinyl sulfone, a maleimide or an orthopyridyl disulfide.

12. The monofunctional polyoxazoline derivative of claim 10, wherein R′

is —

(CH₂)_p— and

p is an integer from 0-25.

13. The monofunctional polyoxazoline derivative of claim 10, wherein R₂ is an inert group.

14. The monofunctional polyoxazoline derivative of claim 10, wherein R₂ and R* are each independently a C₁-C₁₂ alkyl group.

15. The monofunctional polyoxazoline derivative of claim 10, wherein R₂ is methyl, ethyl, isopropyl or n-propyl.

16. The monofunctional polyoxazoline derivative of claim 10, wherein R* is —

(CH₂)_o—

C₆H₅ and o is an integer from 1-25.

17. The monofunctional polyoxazoline derivative of claim 10, wherein the active functional group is protected.

18. The monofunctional polyoxazoline derivative of claim 10, wherein the I′

group is H or methyl.

19. The monofunctional polyoxazoline derivative of claim 10, wherein at least one of POZ_I and POZ_II has a polydispersity value of less than or equal to 1.2, less than or equal to 1.1 or less than or equal to 1.05.

20. The monofunctional polyoxazoline derivative of claim 10, wherein each of the POZ_I and POZ_II has a polydispersity value of less than or equal to 1.2, less than or equal to 1.1 or less than or equal to 1.05.

44. A target molecule-POZ conjugate of the general formula:

A_a-B-TM_t wherein

A is a POZ derivative of claim 10 or claim 31, minus any leaving groups eliminated during the reaction of the active functional group on the POZ derivative with a binding partner on a target molecule;

TM is the target molecule containing the binding partner;

B is a linkage formed between the active functional group and the binding partner;

a is an integer ranging from 1 up to the number of active functional groups on TM; and

t is an integer ranging from 1 up to the number of active functional groups on A.

45. The target molecule-POZ conjugate of claim 44, wherein A is a POZ derivative of claim 10.

21. A heterofunctional polyoxazoline derivative of the general structure:

D-R₃—

POZ—

R₄—

X

wherein;

D is —

OH, —

CO₂H or a group containing an active —

OH group or an active —

CO₂H group;

POZ is a polyoxazoline polymer of the structure —

[N(COR₂)CH₂CH₂]_n

R₃ and R₄ are linking groups;

R₂ is independently selected for each repeating unit of the polyoxazoline polymer from an unsubstituted or substituted alkyl, alkenyl, aralkyl or heterocycylalkyl group;

X is an active functional group or a group capable of being converted to an active functional group, the active functional group capable of forming a linkage with a binding partner on a target molecule; and

n is an integer from 3-1000.

22. The heterofunctional polyoxazoline derivative of claim 21, wherein X is an alkyne, an oxyamine, an aldehyde, a ketone, an acetal, a ketal, an ester, a carboxylic acid, an activated carboxylic acid, an active carbonate, a chloroformate, an alcohol, an azide, a hydrazide, an amine, a protected amine, a thiol, a vinyl sulfone, a maleimide or an orthopyridyl disulfide.

23. The heterofunctional polyoxazoline derivative of claim 21, wherein R₃ is —

(CH₂)_p— and

p is an integer from 1-25.

24. The heterofunctional polyoxazoline derivative of claim. 21, wherein R₄ is —

S—

(CH₂)_o— and

o is an integer from 1-25.

25. The heterofunctional polyoxazoline derivative of claim 21, wherein R₂ is a C₁-C₁₂ alkyl group.

26. The heterofunctional polyoxazoline derivative of claim 21, wherein R₂ is methyl, ethyl, isopropyl or n-propyl.

27. The heterofunctional polyoxazoline derivative of claim 21, wherein the X group is protected.

28. The heterofunctional polyoxazoline derivative of claim 21, wherein the POZ has a polydispersity value of less than or equal to 1.2, less than or equal to 1.1 or less than or equal to 1.05.

29. The heterofunctional polyoxazoline derivative of claim 21, having the structure:

HO—

(CH₂)_p—

POZ—

S—

(CH₂)_o—

X

wherein p and o are integers independently selected from 1-25.

30. The heterofunctional polyoxazoline derivative of claim 21, having the structure:

HO₂C—

(CH₂)_p—

POZ—

S—

(CH₂)_o—

X

wherein p and o are integers independently selected from 1-25.

47. The target molecule-POZ conjugate of claim 44, wherein A is a POZ derivative of any one of claims 21-30.

31. A heterofunctional polyoxazoline of the following general structure:

E-R₃—

{POZ_I—

POZ_II}^a—

S—

R*

wherein;

E is —

OH, —

CO₂H or a group containing an active —

OH group or an active —

CO₂H group;

POZ_I is a polyoxazoline polymer of the structure [N(CO—

R′

—

Z)CH₂CH₂]_m

POZ_II is a polyoxazoline polymer of the structure [N(COR₂)CH₂C_1-2]_n

R′

is an optional linking group

R₃ is a linking group;

Z is an active functional group or a group capable of being converted to an active functional group, the active functional group capable of forming a linkage with a binding partner on a target molecule;

R₂ is independently selected for each repeating unit of the polyoxazoline polymer from an unsubstituted or substituted alkyl, alkenyl, aralkyl or heterocycylalkyl group;

R* is an unsubstituted or substituted alkyl, alkenyl, aralkyl, heterocycylalkyl group or an active functional group or a group capable of being converted to an active functional group, the active functional group capable of forming a linkage with a binding partner on a target molecule;

n is an integer from 0-1000, provided that when n=0, then m is >

1;

m is an integer 1-1000; and

a is ran, which indicates a random copolymer, or block, which indicates a block copolymer.

32. The heterofunctional polyoxazoline derivative of claim 31, wherein at least one of X and R* is independently an alkyne, an oxyamine, an aldehyde, a ketone, an acetal, a ketal, an ester, a carboxylic acid, an activated carboxylic acid, an active carbonate, a chloroformate, an alcohol, an azide, a hydrazide, an amine, a protected amine, a thiol, a vinyl sulfone, a maleimide or an orthopyridyl disulfide.

33. The heterofunctional polyoxazoline derivative of claim 31, wherein R₃ is —

(CH₂)_p—

where p is an integer from 1-25.

34. The heterofunctional polyoxazoline derivative of claim 31, wherein R′

is —

(CH₂)_o—

where o is an integer from 1-25.

35. The heterofunctional polyoxazoline derivative of claim 31, wherein R₂ and R* are each independently a C₁-C₁₂ alkyl or aralkyl group.

36. The heterofunctional polyoxazoline derivative of claim 31, wherein R₂ is methyl, ethyl, isopropyl or n-propyl.

37. The heterofunctional polyoxazoline derivative of claim 31, wherein R* is —

(CH₂)_q—

C₆H₅ and q is an integer from 1-25.

38. The heterofunctional polyoxazoline derivative of claim 31, wherein R* is an inert group.

39. The heterofunctional polyoxazoline derivative of claim 31, wherein at least one active functional group is protected.

40. The heterofunctional polyoxazoline derivative of claim 31, wherein at least one of POZ_I and POZ_II has a polydispersity value of less than or equal to 1.2, less than or equal to 1.1 or less than or equal to 1.05.

41. The heterofunctional polyoxazoline derivative of claim 31, wherein each of the POZ_I and POZ_II has a polydispersity value of less than or equal to 1.2, less than or equal to 1.1 or less than or equal to 1.05.

42. The heterofunctional polyoxazoline derivative of claim 31, having the structure:

HO—

(CH₂)_p—

{POZ_I—

POZ_II}^a—

S—

R*, wherein p is an integer selected from 1-25.

43. The heterofunctional polyoxazoline derivative of claim 31, having the structure:

HO₂C—

(CH₂)_p—

{POZ_I—

POZ_H}^a—

S—

R*, wherein p is an integer selected from 1-25.

46. The target molecule-POZ conjugate of claim 44, wherein A is a POZ derivative of claim 31.

48. The target molecule-POZ conjugate of claim 44, wherein A is a POZ derivative of any one of claims 31-43.

49. The target molecule-POZ conjugate of any one of claims 43-46, wherein the target molecule is an organic small molecule, an oligonucleotide, a polypeptide, an antibody, an antibody fragment, a protein, a carbohydrate a lipid or a combination thereof.

50. The target molecule-POZ conjugate of claim 49, wherein the lipid is a phospholipid.

51. The target molecule-POZ conjugate of any one of claims 43-46, wherein the target molecule is a targeting agent, a diagnostic agent or a therapeutic agent or a combination thereof.

52. A polyoxazoline-phospholipid conjugate comprising a lipid portion linked to a polyoxazoline portion having the structure:

-L_I-{POZ_I—

POZ_II}^a—

S-L_II-R* or I—

{POZ_I—

POZ_II}^a—

S-L_II;

Wherein

POZ_I is a polyoxazoline polymer of the structure —

[N(CO—

R′

—

Z)CH₂CH₂]_m;

POZ_II is a polyoxazoline polymer of the structure [N(COR₂)CH₂CH₂]_n;

R′

, L_I, and L_II are each optional linking groups;

Z is an active functional group or a group capable of being converted to an active functional group, the active functional group capable of forming a linkage with a binding partner on a target molecule;

R₂ is independently selected for each repeating unit of the polyoxazoline polymer from an unsubstituted or substituted alkyl, alkenyl, aralkyl or heterocycylalkyl group;

R* is an unsubstituted or substituted alkyl, alkenyl, aralkyl, heterocycylalkyl group or an active functional group or a group capable of being converted to an active functional group, the active functional group capable of forming a linkage with a binding partner on a target molecule;

I′

is a group present at the initiator position;

n is an integer from 0-1000, provided that when n=0, then m is >

1;

m is an integer 1-1000; and

a is ran, which indicates a random copolymer, or block, which indicates a block copolymer.

53. The polyoxazoline-phospholipid conjugate of claim 52, wherein at least one of Z and R* is independently an alkyne, an oxyamine, an aldehyde, a ketone, an acetal, a ketal, an ester, a carboxylic acid, an activated carboxylic acid, an active carbonate, a chloroformate, an alcohol, an azide, a hydrazide, an amine, a protected amine, a thiol, a vinyl sulfone, a maleimide or an orthopyridyl disulfide.

54. The polyoxazoline-phospholipid conjugate of claim 52, wherein the lipid portion comprises two hydrophobic moieties and a hydrophilic moiety and the lipid portion is linked to the polyoxazoline portion at the hydrophilic moiety.

55. The polyoxazoline-phospholipid conjugate of claim 52, wherein the lipid portion of the polyoxazoline-phospholipid conjugate is a phospholipid or a glycolipid.

56. The polyoxazoline-phospholipid conjugate of claim 52, wherein the phospholipid is selected from the group consisting of:

phosphatidylethanolamine, phosphatidylyholine, phospatidylserine, phosphatidylinositol, phosphatidylglycerol, phosphatidic acid and sphingomyelin.

57. The polyoxazoline-phospholipid conjugate of claim 52, wherein POZ_II is a random or block copolymer.

58. The polyoxazoline-phospholipid conjugate of claim 52, wherein POZ_II is a random or block copolymer containing one or more units of a first polyoxazoline separated by one or more units of a second polyoxazoline, wherein the R₂ groups for the first and second polyoxazoline are independently methyl, ethyl, isopropyl or n-propyl.

59. The polyoxazoline-phospholipid conjugate of claim 52, wherein the lipid portion is a phospholipid and the polyoxazoline-phospholipid conjugate has the general structure:

60. The polyoxazoline-phospholipid conjugate of claim 59, wherein R* is an alkyne, an oxyamine, an aldehyde, a ketone, an acetal, a ketal, an ester, a carboxylic acid, an activated carboxylic acid, an active carbonate, a chloroformate, an alcohol, an azide, a hydrazide, an amine, a protected amine, a thiol, a vinyl sulfone, a maleimide or an orthopyridyl disulfide.

61. The polyoxazoline-phospholipid conjugate of claim 59, wherein R* is an inert group.

62. The polyoxazoline-phospholipid conjugate of claim 52, wherein the lipid portion is a phospholipid and the polyoxazoline-phospholipid conjugate has the general structure:

63. The polyoxazoline-phospholipid conjugate of claim 62, wherein I is an inert initiating group selected from the group consisting of H and alkyl.

64. The polyoxazoline-phospholipid conjugate of claim 59, wherein the phospholipid is selected from the group consisting of:

phosphatidylethanolamine, phosphatidylyholine, phospatidylserine, phosphatidylinositol, phosphatidylglycerol, phosphatidic acid and sphingomyelin.

65. The polyoxazoline-phospholipid conjugate of any one of claim 59 or 62, wherein L_I and L_II are each independently selected from the group consisting of:

—

(CH₂)_f—

NHCO—

(CH₂)_g—

, —

(CH₂)_f—

NHCO₂—

(CH₂)_g— and

—

(CH₂)_h—

wherein f, g and h are each an integer independently selected from 0-10.

66. The polyoxazoline-phospholipid conjugate of any one of claim 59 or 62, wherein POZ_if is a random or block copolymer.

67. The polyoxazoline-phospholipid conjugate of any one of claim 59 or 62, wherein POZ_II is a random or block copolymer containing one or more units of a first polyoxazoline, separated by one or more units of a second polyoxazoline, wherein the R₂ groups for the first and second polyoxazolines are independently methyl, ethyl, isopropyl or n-propyl.

68. The polyoxazoline-phospholipid conjugate of any one of claim 59 or 62, wherein R_H1 and R_H2 are each independently C14 to C24 saturated alkyl groups or C14 to C24 unsaturated alkyl groups.

69. A liposomal composition comprising liposomes, the liposomal composition comprising a vesicle forming lipid and a polyoxazoline-phospholipid conjugate of any one of claims 52-68, wherein the liposomes have a size from about 0.025 microns to about 10 microns.

70. The liposomal composition of claim 69, wherein the polyoxazoline-phospholipid conjugate is present at a concentration of about 1 mole percent to about 50 mole percent.

71. The liposomal composition of claim 69, wherein vesicle forming lipid is a phospholipid.

72. The liposomal composition of claim 71, wherein the phospholipid is phosphatidylethanolamine, phosphatidylyholine, phospatidylserine, phosphatidylinositol, phosphatidylglycerol, phosphatidic acid and sphingomyelin.

73. The liposomal composition of claim 69, further comprising a target molecule.

74. The liposomal composition of claim 69, wherein the target molecule is linked to the polyoxazoline-phospholipid conjugate or entrapped within the liposome.

75. The liposomal composition of claim 69, wherein the target molecule is an organic small molecule, an oligonucleotide, a polypeptide, an antibody, an antibody fragment, a protein, or a carbohydrate.

76. The liposomal composition of claim 69, wherein the target molecule is a targeting agent, a diagnostic agent or a therapeutic agent.

77. The liposomal composition of claim 69, wherein the target molecule is exposed to the extra-liposomal environment.