Claims
- 1. A method of synthesizing a diketopiperazine of the formula:
- 2. The method of claim 1 wherein the first amino acid is alanine.
- 3. The method of claim 1 wherein R5 is benzyl.
- 4. The method of claim 2 wherein R5 is benzyl.
- 5. The method of claim 1 wherein the dipeptide is cyclized by heating it under neutral conditions.
- 6. The method of claim 5 wherein dipeptide is refluxed in a neutral solvent.
- 7. The method of claim 6 wherein the neutral solvent is a combination ofbutan-2-ol and toluene.
- 8. The method of claim 1 wherein the R5 group is removed by hydrogenation of the diketopiperazine formed in step (c).
- 9. The method of claim 8 wherein the diketopiperazine of step (c) is hydrogenated using a palladium on carbon catalyst.
- 10. The method of claim 1 further comprising converting the product of step (d) to a compound of formula 2 wherein R3 is other than —OH.
- 11. A method of synthesizing a diketopiperazine of the formula:
- 12. The method of claim 11 wherein the first amino acid is alanine.
- 13. The method of claim 11 wherein R5 is benzyl.
- 14. The method of claim 12 wherein R5 is benzyl.
- 15. The method of claim 11 wherein the dipeptide is cyclized by heating it under neutral conditions.
- 16. The method of claim 15 wherein dipeptide is refluxed in a neutral solvent.
- 17. The method of claim 16 wherein the neutral solvent is a combination of butan-2-ol and toluene.
- 18. The method of claim 1 wherein the R5 group is removed by hydrogenation of the diketopiperazine formed in step (d).
- 19. The method of claim 18 wherein the diketopiperazine of step (d) is hydrogenated using a palladium on carbon catalyst.
- 20. The method of claim 11 further comprising converting the product of step (e) to a compound of formula 2 wherein R3 is other than —OH.
Parent Case Info
[0001] This application claims benefit of provisional application 60/223,075 filed Aug. 4, 2000.
Provisional Applications (1)
|
Number |
Date |
Country |
|
60223075 |
Aug 2000 |
US |