Treatment of T-cell mediated diseases
View Patent ↗The invention provides a method of treating T-cell mediated diseases and a method of inhibiting the activation of T-cells using certain diketopiperazines. The invention also provides methods of synthesizing diketopiperazines and pharmaceutical compositions comprising certain diketopiperazines. The invention further provides methods of making improved pharmaceutical compositions of proteins and peptides by either increasing or decreasing the content of diketopiperazines in the compositions and the resultant improved pharmaceutical compositions.
1. A method of reducing the symptoms, severity or both of a T-cell mediated disease comprising administering to an animal in need thereof an effective amount of a diketopiperazine having the following formula:
wherein:
R 1 and R 2 , which may be the same or different, each is:
(a) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, seine, homoserine, threonine, lysine, hydroxylysine, arginine, homoarginine, citrulline, p-aminophenylalanine, tyrosine, thyroxine or ornithine; or
(b) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (a), and the derivatized side chain has:
(i) an —NH 2 group replaced by an —NHR 3 or —N(R 3 ) 2 group, wherein each R 3 may independently be a substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, aryl, alkylaryl, arylalkyl or heteroaryl;
(ii) an —OH group replaced by an —O—PO 3 H 2 or —OR 3 group, wherein each R 3 may independently be a substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, aryl, alkylaryl, arylalkyl or heteroaryl;
(iii) a —CH 2 — group replaced by a —CH(NH 2 )— or a —CH(OH)— group;
(iv) a —CH 3 group replaced by a —CH 2 —NH 2 or a —CH 2 —OH group; and/or
(v) an H which is attached to a carbon atom replaced by a halogen; or
a physiologically-acceptable salt thereof.
2. The method of claim 1 wherein R 1 and R 3 , which may be the same or different, each is:
(c) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, arginine, homoarginine, citrulline or ornithine; or
(d) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (c), and the derivatized side chain is as defined in claim 1 .
3. The method of claim 1 wherein R 1 and R 2 are both a hydrophobic side chain or a hydrophobic side chain derivative.
4. The method of claim 3 wherein R 1 and R 2 , which may be the same or different, each is the side chain of glycine, alanine, valine, norvaline, α-aminobutyric acid, leucine, isoleucine or norleucine.
5. The method of claim 4 wherein R 1 is the side chain of glycine and R 2 is the side chain of leucine.
6. The method of claim 1 wherein the animal is a human.
7. The method of any one of claims 1 - 6 wherein the T-cell mediated disease is graft rejection, graft versus host disease, an unwanted delayed-type hypersensitivity reaction, a T-cell mediated pulmonary disease or an autoimmune disease.
8. The method of any one of claims 1 - 6 wherein the T-cell mediated disease is multiple sclerosis, neuritis, polymyositis, psoriasis, vitiligo, Sjogren's syndrome, rheumatoid arthritis, Type 1 diabetes, autoimmune pancreatitis, inflammatory bowel diseases, Crohn's disease, ulcerative colitis, celiac disease, glomerulonephritis, scleroderma, sarcoidosis, autoimmune thyroid diseases, Hashimoto's thyroiditis, Graves disease, myasthenia gravis, Addison's disease, autoimmune uveoretinitis, pemphigus vulgaris, primary biliary cirrhosis, pernicious anemia, or systemic lupus erythematosis.
9. The method of any one of claims 1 - 6 wherein the T-cell mediated disease is pulmonary fibrosis or idiopathic pulmonary fibrosis.
10. A method of inhibiting activation of T-cells comprising administering to an animal in need thereof an effective amount of a diketopiperazine having the following formula:
wherein:
R 1 and R 2 , which may be the same or different, each is:
(a) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, histidine, arginine, homoarginine, citrulline, phenylalanine, p-aminophenylalanine, tyrosine, tryptophan, thyroxine, cysteine, homocysteine, methionine, penicillamine or ornithine; or
(b) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (a), and the derivatized side chain has:
(i) an —NH 2 group replaced by an —NHR 3 or —N(R 3 ) 2 group, wherein each R 3 may independently be a substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, aryl, alkylaryl, arylalkyl or heteroaryl;
(ii) an —OH group replaced by an —O—PO 3 H 2 or —OR 3 group, wherein each R 3 may independently be a substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, aryl, alkylaryl, arylalkyl or heteroaryl;
(iii) an —SH group replaced by —S—S—CH 2 —CH(NH 2 )—COOH or —S—S—CH 2 —CH 2 —CH(NH 2 )—COOH;
(iv) a —CH 2 — group replaced by a —CH(NH 2 )— or a —CH(OH)— group;
(v) a —CH 3 group replaced by a —CH 2 —NH 2 or a —CH 2 —OH group; and/or
(vi) an H which is attached to a carbon atom replaced by a halogen; or
a physiologically-acceptable salt thereof.
11. The method of claim 10 wherein R 1 and R 2 , which may be the same or different, each is:
(c) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, histidine, arginine, homoarginine, citrulline, phenylalanine, p-aminophenylalanine, tyrosine, tryptophan, thyroxine or ornithine; or
(d) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (c), and the derivatized side chain is as defined in claim 10 .
12. The method of claim 10 wherein R 1 and R 2 , which may be the same or different, each is:
(c) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, arginine, homoarginine, citrulline, p-aminophenylalanine, tyrosine, thyroxine, cysteine, homocysteine, methionine, penicillamine or ornithine; or
(d) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (c), and the derivatized side chain is as defined in claim 10 .
13. The method of claim 10 wherein R 1 and R 2 , which may be the same or different, each is:
(c) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, arginine, homoarginine, citrulline, p-aminophenylalanine, tyrosine, thyroxine or ornithine;
(d) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (c), and the derivatized side chain is as defined in claim 10 .
14. The method of claim 10 wherein R 1 and R 2 are both a hydrophobic side chain or a hydrophobic side chain derivative.
15. The method of claim 14 wherein R 1 and R 2 , which may be the same or different, each is the side chain of glycine, alanine, valine, norvaline, α-aminobutyric acid, leucine, isoleucine or norleucine.
16. The method of claim 15 wherein R 1 is the side chain of glycine and R 2 is the side chain of leucine.
17. The method of claim 1 wherein R 1 , R 2 or both is the side chain of methionine, the side chain of arginine or a derivative of these side chains.
18. The method of claim 17 wherein R 1 is the side chain of methionine and R 3 is the side chain of arginine.
19. The method of claim 1 wherein the animal is a human.
20. A method of treating inflammation or an inflammatory disease involving, caused by or exacerbated by T-cells, the method comprising administering to an animal in need thereof an effective amount of a diketopiperazine having the following formula:
wherein:
R 1 and R 2 , which may be the same or different, each is:
(a) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, histidine, arginine, homoarginine, citrulline, phenylalanine, p-aminophenylalanine, tyrosine, tryptophan, thyroxine, cysteine, homocysteine, methionine, penicillamine or ornithine; or
(b) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (a), and the derivatized side chain has:
(i) an —NH 2 group replaced by an —NHR 3 or —N(R 3 ) 2 group, wherein each R 3 may independently be a substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, aryl, alkylaryl, arylalkyl or heteroaryl;
(ii) an —OH group replaced by an —O—PO 3 H 2 or —OR 3 group, wherein each R 3 may independently be a substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, aryl, alkylaryl, arylalkyl or heteroaryl;
(iii) an —SH group replaced by —S—S—CH 2 —CH(NH 2 )—COOH or —S—S—CH 2 —CH 2 —CH(NH 2 )—COOH;
(iv) a —CH 2 — group replaced by a —CH(NH 2 )— or a —CH(OH)— group;
(v) a —CH 3 group replaced by a —CH 2 —NH 2 or a —CH 2 —OH group; and/or
(vi) an H which is attached to a carbon atom replaced by a halogen; or
a physiologically-acceptable salt thereof.
21. The method of claim 20 wherein R 1 and R 2 , which may be the same or different, each is:
(c) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, histidine, arginine, homoarginine, citrulline, phenylalanine, p-aminophenylalanine, tyrosine, tryptophan, thyroxine or ornithine; or
(d) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (c), and the derivatized side chain is as defined in claim 20 .
22. The method of claim 20 wherein R 1 and R 2 , which may be the same or different, each is:
(c) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, arginine, homoarginine, citrulline, p-aminophenylalanine, tyrosine, thyroxine, cysteine, homocysteine, methionine, penicillamine or ornithine; or
(d) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (c), and the derivatized side chain is as defined in claim 20 .
23. The method of claim 20 wherein R 1 and R 2 , which may be the same or different, each is:
(c) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, seine, homoserine, threonine, lysine, hydroxylysine, arginine, homoarginine, citrulline, p-aminophenylalanine, tyrosine, thyroxine or ornithine; or
(d) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (c), and the derivatized side chain is as defined in claim 20 .
24. The method of claim 20 wherein R 1 and R 2 are both a hydrophobic side chain or a hydrophobic side chain derivative.
25. The method of claim 24 wherein R 1 and R 3 , which may be the same or different, each is the side chain of glycine, alanine, valine, norvaline, α-aminobutyric acid, leucine, isoleucine or norleucine.
26. The method of claim 25 wherein R 1 is the side chain of glycine and R 3 is the side chain of leucine.
27. The method of claim 20 wherein R 1 , R 2 or both is the side chain of methionine, the side chain of arginine or a derivative of these side chains.
28. The method of claim 27 wherein R 1 is the side chain of methionine and R 3 is the side chain of arginine.
29. The method of claim 20 wherein the animal is a human.
30. A method of treating a T-cell mediated pulmonary disease comprising administering to an animal in need thereof an effective amount of a diketopiperazine having the following formula:
wherein:
R 1 and R 2 , which may be the same or different, each is:
(a) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, histidine, arginine, homoarginine, citrulline, phenylalanine, p-aminophenylalanine, tyrosine, tryptophan, thyroxine, cysteine, homocysteine, methionine, penicillamine or ornithine;
(b) R 1 is —CH 2 —CH 2 —CH 2 — or —CH 2 —CH(OH)—CH 2 — and together with the adjacent ring nitrogen forms proline or hydroxyproline, or R 3 is —CH 2 —CH 2 —CH 2 — or —CH 2 —CH(OH)—CH 2 — and together with the adjacent ring nitrogen forms proline or hydroxyproline; or
(c) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (a), and the derivatized side chain has:
(i) an —NH 2 group replaced by an —NHR 3 or —N(R 3 ) 2 group, wherein each R 3 may independently be a substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, aryl, alkylaryl, arylalkyl or heteroaryl;
(ii) an —OH group replaced by an —O—PO 3 H 2 or —OR 3 group, wherein each R 3 may independently be a substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, aryl, alkylaryl, arylalkyl or heteroaryl;
(iii) an —SH group replaced by —S—S—CH 2 —CH(NH 2 )—COOH or —S—S—CH 2 —CH 2 —CH(NH 2 )—COOH;
(iv) a —CH 2 — group replaced by a —CH(NH 2 )— or a —CH(OH)— group;
(v) a —CH 3 group replaced by a —CH 2 —NH 2 or a —CH 2 —OH group; and/or
(vi) an H which is attached to a carbon atom replaced by a halogen; or
a physiologically-acceptable salt thereof.
31. The method of claim 30 wherein R 1 and R 2 , which may be the same or different, each is:
(d) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, histidine, arginine, homoarginine, citrulline, phenylalanine, p-aminophenylalanine, tyrosine, tryptophan, thyroxine or ornithine;
(e) R 1 is —CH 2 —CH 2 —CH 2 — or —CH 2 —CH(OH)—CH 2 — and together with the adjacent ring nitrogen forms proline or hydroxyproline, or R 2 is —CH 2 —CH 2 —CH 2 — or CH(OH)—CH 2 — and together with the adjacent ring nitrogen forms proline or hydroxyproline; or
(f) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (d), and the derivatized side chain is as defined in claim 30 .
32. The method of claim 30 wherein R 1 and R 2 , which may be the same or different, each is:
(d) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, arginine, homoarginine, citrulline, p-aminophenylalanine, tyrosine, thyroxine, cysteine, homocysteine, methionine, penicillamine or ornithine;
(e) R 1 is —CH 2 —CH 2 —CH 2 — or —CH 2 —CH(OH)—CH 2 — and together with the adjacent ring nitrogen forms proline or hydroxyproline, or R 2 is —CH 2 —CH 2 —CH 2 — or CH(OH)—CH 2 — and together with the adjacent ring nitrogen forms proline or hydroxyproline; or
(f) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (d), and the derivatized side chain is as defined in claim 30 .
33. The method of claim 30 wherein R 1 and R 2 , which may be the same or different, each is:
(d) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, arginine, homoarginine, citrulline, p-aminophenylalanine, tyrosine, thyroxine or ornithine;
(e) R 1 is —CH 2 —CH 2 —CH 2 — or —CH 2 —CH(OH)—CH 2 — and together with the adjacent ring nitrogen forms proline or hydroxyproline, or R 2 is —CH 2 —CH 2 —CH 2 — or —CH 2 —CH(OH)—CH 2 — and together with the adjacent ring nitrogen forms proline or hydroxyproline; or
(f) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (d), and the derivatized side chain is as defined in claim 30 .
34. The method of claim 30 wherein R 1 and R 3 , which may be the same or different, each is:
(d) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, histidine, arginine, homoarginine, citrulline, phenylalanine, p-aminophenylalanine, tyrosine, tryptophan, thyroxine or ornithine;
(e) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (d), and the derivatized side chain is as defined in claim 30 .
35. The method of claim 30 wherein R 1 and R 2 , which may be the same or different, each is:
(d) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, seine, homoserine, threonine, lysine, hydroxylysine, arginine, homoarginine, citrulline, p-aminophenylalanine, tyrosine, thyroxine, cysteine, homocysteine, methionine, penicillamine or ornithine;
(e) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (d), and the derivatized side chain is as defined in claim 30 .
36. The method of claim 30 wherein R 1 and R 3 , which may be the same or different, each is:
(d) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, seine, homoserine, threonine, lysine, hydroxylysine, arginine, homoarginine, citrulline, p-aminophenylalanine, tyrosine, thyroxine or ornithine; or
(e) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (d), and the derivatized side chain is as defined in claim 30 .
37. The method of claim 30 wherein R 1 and R 2 are both a hydrophobic side chain or a hydrophobic side chain derivative.
38. The method of claim 37 wherein:
(d) R 1 and R 2 , which may be the same or different, each is the side chain of glycine, alanine, valine, norvaline, α-aminobutyric acid, leucine, isoleucine, norleucine or phenylalanine; or
(e) —R 3 is the side chain of glycine, alanine, valine, norvaline, α-aminobutyric acid, leucine, isoleucine, norleucine or phenylalanine, and R 1 is —CH 2 —CH 2 —CH 2 — and together with the adjacent nitrogen atom forms proline.
39. The method of claim 38 wherein R 1 is —CH 2 —CH 2 —CH 2 — and together with the adjacent nitrogen atom forms proline and R 2 is the side chain of phenylalanine.
40. The method of claim 38 wherein R 1 is —CH 2 —CH 2 —CH 2 — and together with the adjacent nitrogen atom forms proline and R 2 is the side chain of alanine.
41. The method of claim 38 wherein R 1 and R 2 , which may be the same or different, each is the side chain of glycine, alanine, valine, norvaline, α-aminobutyric acid, leucine, isoleucine or norleucine.
42. The method of claim 41 wherein R 1 is the side chain of glycine and R 2 is the side chain of leucine.
43. The method of claim 30 wherein R 1 , R 2 or both is the side chain of methionine, the side chain of arginine or a derivative of these side chains.
44. The method of claim 43 wherein R 1 is the side chain of methionine and R 3 is the side chain of arginine.
45. The method of claim 30 wherein the animal is a human.
46. The method of any one of claims 30 - 45 wherein the T-cell mediated pulmonary disease is pulmonary fibrosis or idiopathic pulmonary fibrosis.
47. A method of reducing the symptoms, severity or both of a T-cell mediated autoimmune disease comprising administering to an animal in need thereof an effective amount of a diketopiperazine having the following formula:
wherein:
R 1 and R 2 , which may be the same or different, each is:
(a) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, seine, homoserine, threonine, lysine, hydroxylysine, arginine, homoarginine, citrulline, p-aminophenylalanine, tyrosine, thyroxine or ornithine;
(b) R 1 is —CH 2 —CH 2 —CH 2 — or —CH 2 —CH(OH)—CH 2 — and together with the adjacent ring nitrogen forms proline or hydroxyproline, or R 3 is —CH 2 —CH 2 —CH 2 — or —CH 2 —CH(OH)—CH 2 — and together with the adjacent ring nitrogen forms proline or hydroxyproline; or
(c) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (a), and the derivatized side chain has:
(i) an —NH 2 group replaced by an —NHR 3 or —N(R 3 ) 2 group, wherein each R 3 may independently be a substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, aryl, alkylaryl, arylalkyl or heteroaryl;
(ii) an —OH group replaced by an —O—PO 3 H 2 or —OR 3 group, wherein each R 3 may independently be a substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, aryl, alkylaryl, arylalkyl or heteroaryl;
(iii) a —CH 2 — group replaced by a —CH(NH 2 )— or a —CH(OH)— group;
(iv) a —CH 3 group replaced by a —CH 2 —NH 2 or a —CH 2 —OH group; and/or
(v) an H which is attached to a carbon atom replaced by a halogen; or
a physiologically-acceptable salt thereof.
48. The method of claim 47 wherein R 1 and R 2 , which may be the same or different, each is:
(d) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, arginine, homoarginine, citrulline or ornithine;
(e) R 1 is —CH 2 —CH 2 —CH 2 — or —CH 2 —CH(OH)—CH 2 — and together with the adjacent ring nitrogen forms proline or hydroxyproline, or R 2 is —CH 2 —CH 2 —CH 2 — or CH(OH)—CH 2 — and together with the adjacent ring nitrogen forms proline or hydroxyproline; or
(f) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (d), and the derivatized side chain is as defined in claim 47 .
49. The method of claim 47 wherein R 1 and R 2 , which may be the same or different, each is:
(d) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, arginine, homoarginine, citrulline, p-aminophenylalanine, tyrosine, thyroxine or ornithine; or
(e) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (d), and the derivatized side chain is as defined in claim 47 .
50. The method of claim 47 wherein R 1 and R 2 , which may be the same or different, each is:
(d) a side chain of an amino acid, wherein the amino acid is glycine, alanine, valine, norvaline, α-aminoisobutyric acid, 2,4-diaminobutyric acid, 2,3-diaminobutyric acid, leucine, isoleucine, norleucine, serine, homoserine, threonine, lysine, hydroxylysine, arginine, homoarginine, citrulline or ornithine; or
(e) a derivative of a side chain of an amino acid, wherein the amino acid is one of those recited in (d), and the derivatized side chain is as defined in claim 47 .
51. The method of claim 47 wherein R 1 and R 2 are both a hydrophobic side chain or a hydrophobic side chain derivative.
52. The method of claim 51 wherein:
(d) R 1 and R 2 , which may be the same or different, each is the side chain of glycine, alanine, valine, norvaline, α-aminobutyric acid, leucine, isoleucine or norleucine; or
(e) —R 2 is the side chain of glycine, alanine, valine, norvaline, α-aminobutyric acid, leucine, isoleucine or norleucine, and R 1 is —CH 2 —CH 2 —CH 2 — and together with the adjacent nitrogen atom forms proline.
53. The method of claim 52 wherein R 1 is —CH 2 —CH 2 —CH 2 — and together with the adjacent nitrogen atom forms proline and R 3 is the side chain of alanine.
54. The method of claim 51 wherein R 1 and R 2 , which may be the same or different, each is the side chain of glycine, alanine, valine, norvaline, α-aminobutyric acid, leucine, isoleucine or norleucine.
55. The method of claim 54 wherein R 1 is the side chain of glycine and R 2 is the side chain of leucine.
56. The method of claim 47 wherein the animal is a human.
57. The method of any one of claims 47 - 56 wherein the autoimmune disease is multiple sclerosis, neuritis, polymyositis, psoriasis, vitiligo, Sjogren's syndrome, rheumatoid arthritis, Type 1 diabetes, autoimmune pancreatitis, inflammatory bowel diseases, Crohn's disease, ulcerative colitis, celiac disease, glomerulonephritis, sarcoidosis, autoimmune thyroid diseases, Hashimoto's thyroiditis, Graves disease, myasthenia gravis, Addison's disease, autoimmune uveoretinitis, pemphigus vulgaris, primary biliary cirrhosis, pernicious anemia or systemic lupus erythematosis.
58. The method of claim 57 wherein the autoimmune disease is multiple sclerosis.
59. The method of claim 57 wherein the autoimmune disease is systemic lupus erythematosis.