Details for Patent: 5,686,567

Title:	Platelet aggregation inhibitors
Abstract:	An assay for screening snake venom for the presence or absence of platelet aggregation inhibitors (PAIs) based on specific receptor binding is described. Using this assay, the identification and characterization of PAIs in a wide range of snake venom samples was accomplished. The isolated and purified PAI from several of these active snake venoms is described and characterized. In addition, PAIs lacking the Arg-Gly-Asp (RGD) adhesion sequence but containing K*-(G/Sar)-D wherein K is a modified lysyl residue of the formula wherein each R.sup.1 is independently H, alkyl(1-6C) or at most one R.sup.1 is R.sup.2 --C.dbd.NR.sup.3 wherein R.sup.2 is H, alkyl(1-6C), phenyl or benzyl, or is NR.sup.4.sub.2 in which each R.sup.4 is independently H or alkyl(1-6C) and R.sup.3 is H, alkyl(1-6C), phenyl or benzyl, or R.sup.2 --C.dbd.NR.sup.3 is a radical selected from the group consisting of: ##STR1## where m is an integer of 2-3, and each R.sup.5 is independently H or alkyl(1-6C); and wherein one or two (CH.sub.2) may be replaced by O or S provided said O or S is not adjacent to another heteroatom are prepared and shown to specifically inhibit the binding of fibrinogen or von Willebrand Factor to GP IIb-IIIa.
Inventor(s):	Scarborough; Robert M. (Belmont, CA), Wolf; David Lawrence (Palo Alto, CA), Charo; Israel F. (Lafayette, CA)
Assignee:	COR Therapeutics, Inc. (San Francisco, CA)
Filing Date:	Jun 05, 1995
Application Number:	08/462,698
Claims:	1. A compound of the formula: ##STR10## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, G or Sar is G, AA.sub.2 is O-methyltyrosine, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR11## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 2. A compound according to claim 1 having the formula: 3. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 2. 4. A compound comprising a platelet aggregation inhibitor of the formula: ##STR12## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, G or Sar is G, AA.sub.2 is O-methyltyrosine, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR13## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 5. A compound according to claim 4, the platelet aggregation inhibitor having the formula: ##STR14## 6. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 5. 7. A compound consisting essentially of a platelet aggregation inhibitor that inhibits (a) binding of Fg or vWF to GP IIb-IIIa more than (b) binding of vitronectin to vitronectin receptor or fibronectin to fibronectin receptor, which platelet aggregation inhibitor has the formula: ##STR15## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, G or Sar is G, AA.sub.2 is O-methyltyrosine, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR16## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 8. A compound according to claim 7, having the formula: ##STR17## 9. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 8. 10. A pharmaceutical composition which comprises a compound as in any one of claims 1-9 in admixture with a pharmaceutically acceptable excipient. 11. The compound of claim 10, wherein said compound is present in an amount effective to inhibit platelet aggregation. 12. A compound of the formula: ##STR18## wherein Y.sub.1 -X.sub.1 is Acetyl-Cys, n1 is 0, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR19## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 13. A compound according to claim 12 having the formula: ##STR20## 14. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 13. 15. A compound comprising a platelet aggregation inhibitor of the formula: ##STR21## wherein Y.sub.1 -X.sub.1 is Acetyl-Cys, n1 is 0, G or Sar is G, AA.sub. 2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR22## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 16. A compound according to claim 15, the platelet aggregation inhibitor having the formula: ##STR23## 17. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 16. 18. A compound consisting essentially of a platelet aggregation inhibitor that inhibits (a) binding of Fg or vWF to GP IIb-IIIa more than (b) binding of vitronectin to vitronectin receptor or fibronectin to fibronectin receptor, which platelet aggregation inhibitor has the formula: ##STR24## wherein Y.sub.1 -X.sub.1 is Acetyl-Cys, n1 is 0, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR25## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 19. A compound according to claim 18, having the formula: ##STR26## 20. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 19. 21. A pharmaceutical composition which comprises a compound according to any of claim 12-20 in admixture with a pharmaceutically acceptable excipient. 22. The compound of claim 21, wherein said compound is present in an amount effective to inhibit platelet aggregation. 23. A compound of the formula: ##STR27## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is penicillamine, Y.sub.2 is NH.sub.2, and ##STR28## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 24. A compound according to claim 23 having the formula: ##STR29## 25. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 24. 26. A compound comprising a platelet aggregation inhibitor of the formula: ##STR30## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is penicillamine, Y.sub.2 is NH.sub.2, and ##STR31## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 27. A compound according to claim 26, the platelet aggregation inhibitor having the formula: ##STR32## 28. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 27. 29. A compound consisting essentially of a platelet aggregation inhibitor that inhibits (a) binding of Fg or vWF to GP IIb-IIIa more than (b) binding of vitronectin to vitronectin receptor or fibronectin to fibronectin receptor, which platelet aggregation inhibitor has the formula: ##STR33## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is penicillamine, Y.sub.2 is NH.sub.2, and ##STR34## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 30. A compound according to claim 29, having the formula: ##STR35## 31. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 30. 32. A pharmaceutical composition which comprises a compound according to any of claim 23-31 in admixture with a pharmaceutically acceptable excipient. 33. The compound of claim 32, wherein said compound is present in an amount effective to inhibit platelet aggregation. 34. A compound of the formula: ##STR36## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, K* is acetimidyl-Lys, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR37## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 35. A compound according to claim 34 having the formula: ##STR38## 36. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 35. 37. A compound comprising a platelet aggregation inhibitor of the formula: ##STR39## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, K* is acetimidyl-Lys, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR40## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 38. A compound according to claim 37, the platelet aggregation inhibitor having the formula: ##STR41## 39. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 38. 40. A compound consisting essentially of a platelet aggregation inhibitor that inhibits (a) binding of Fg or vWF to GP IIb-IIIa more than (b) binding of vitronectin to vitronectin receptor or fibronectin to fibronectin receptor, which platelet aggregation inhibitor has the formula: ##STR42## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, K* is acetimidyl-Lys, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR43## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 41. A compound according to claim 40, having the formula: ##STR44## 42. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 41. 43. A pharmaceutical composition which comprises a compound according to any of claim 34-42 in admixture with a pharmaceutically acceptable excipient. 44. The compound of claim 43, wherein said compound is present in an amount effective to inhibit platelet aggregation. 45. A compound of the formula: ##STR45## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, K* is acetimidyl-Lys, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is penicillamine, Y.sub.2 is NH.sub.2, and ##STR46## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 46. A compound according to claim 45 having the formula: ##STR47## 47. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 46. 48. A compound comprising a platelet aggregation inhibitor of the formula: ##STR48## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, K* is acetimidyl-Lys, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is penicillamine, Y.sub.2 is NH.sub.2, and ##STR49## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 49. A compound according to claim 48, the platelet aggregation inhibitor having the formula: ##STR50## 50. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 49. 51. A compound consisting essentially of a platelet aggregation inhibitor that inhibits (a) binding of Fg or vWF to GP IIb-IIIa more than (b) binding of vitronectin to vitronectin receptor or fibronectin to fibronectin receptor, which platelet aggregation inhibitor has the formula: ##STR51## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, K* is acetimidyl-Lys, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is penicillamine, Y.sub.2 is NH.sub.2, and ##STR52## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 52. A compound according to claim 51, having the formula: ##STR53## 53. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 52. 54. A pharmaceutical composition which comprises a compound according to any of claim 45-53 in admixture with a pharmaceutically acceptable excipient. 55. The compound of claim 54, wherein said compound is present in an amount effective to inhibit platelet aggregation. 56. A compound of the formula: ##STR54## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, K* is N.sup.G,N.sup.G '-ethylene-Har, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR55## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 57. A compound according to claim 56 having the formula: ##STR56## 58. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 57. 59. A compound comprising a platelet aggregation inhibitor of the formula: ##STR57## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, K* is N.sup.G,N.sup.G '-ethylene-Har, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR58## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 60. A compound according to claim 59, the platelet aggregation inhibitor having the formula: ##STR59## 61. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 60. 62. A compound consisting essentially of a platelet aggregation inhibitor that inhibits (a) binding of Fg or vWF to GP IIb-IIIa more than (b) binding of vitronectin to vitronectin receptor or fibronectin to fibronectin receptor, which platelet aggregation inhibitor has the formula: ##STR60## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, K* is N.sup.G,N.sup.G '-ethylene-Har, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR61## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 63. A compound according to claim 62, having the formula: ##STR62## 64. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 63. 65. A pharmaceutical composition which comprises a compound according to any of claim 56-64 in admixture with a pharmaceutically acceptable excipient. 66. The compound of claim 65, wherein said compound is present in an amount effective to inhibit platelet aggregation. 67. A compound of the formula: ##STR63## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, K* is Har, G or Sar is Sar, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR64## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 68. A compound according to claim 67 having the formula: ##STR65## 69. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 68. 70. A compound comprising a platelet aggregation inhibitor of the formula: ##STR66## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, K* is Har, G or Sar is Sar, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR67## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 71. A compound according to claim 70, the platelet aggregation inhibitor having the formula: ##STR68## 72. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 71. 73. A compound consisting essentially of a platelet aggregation inhibitor that inhibits (a) binding of Fg or vWF to GP IIb-IIIa more than (b) binding of vitronectin to vitronectin receptor or fibronectin to fibronectin receptor, which platelet aggregation inhibitor has the formula: ##STR69## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, K* is Har, G or Sar is Sar, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR70## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 74. A compound according to claim 73, having the formula: ##STR71## 75. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 74. 76. A pharmaceutical composition which comprises a compound according to any of claim 67-75 in admixture with a pharmaceutically acceptable excipient. 77. The compound of claim 76, wherein said compound is present in an amount effective to inhibit platelet aggregation. 78. A compound of the formula: ##STR72## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, K* is phenylimidyl-Lys, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR73## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 79. A compound according to claim 78 having the formula: ##STR74## 80. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 79. 81. A compound comprising a platelet aggregation inhibitor of the formula: ##STR75## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, K* is phenylimidyl-Lys, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR76## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 82. A compound according to claim 81, the platelet aggregation inhibitor having the formula: ##STR77## 83. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 82. 84. A compound consisting essentially of a platelet aggregation inhibitor that inhibits (a) binding of Fg or vWF to GP IIb-IIIa more than (b) binding of vitronectin to vitronectin receptor or fibronectin to fibronectin receptor, which platelet aggregation inhibitor has the formula: ##STR78## wherein Y.sub.1 -X.sub.1 is Mpr, n1 is 0, K* is phenylimidyl-Lys, G or Sar is G, AA.sub.2 is W, n2 is 1, AA.sub.3 is a proline residue, n3 is 1, n4 is 0, X.sub.2 is C, Y.sub.2 is NH.sub.2, and ##STR79## represents a disulfide bond, or a physiologically acceptable basic or acid addition salt thereof. 85. A compound according to claim 84, having the formula: ##STR80## 86. A compound comprising a physiologically acceptable acid addition salt of the compound of claim 85. 87. A pharmaceutical composition which comprises a compound according to any of claim 78-86 in admixture with a pharmaceutically acceptable excipient. 88. The compound of claim 87, wherein said compound is present in an amount effective to inhibit platelet aggregation.