Cephalotaxane derivatives and their processes of preparation and purification

Abstract

The present invention concerns a new general process for asymmetric hemisynthesis of harringtonines and their analogs, that are alkaloids used in chemotherapy. This process comprises direct esterification of a natural cephalotaxine with an acylating compound constituted of a side chain precursor which backbone and functionalization are entirely preformed. The invention also concerns a natural, synthetic or semi-synthetic harringtonines including their tautomeric forms and their salts of the following formula: wherein n=2 (i.e. harringtonine) or n=3 (i.e. homoharringtonine), in which the total content of impurities, possibly including enantiomeric forms, is lower than 1%, and/or the content of the major impurity is lower than 0.9%, and/or the chromatographic assay exhibits a harringtonines content higher than 97.5%.

The invention claimed is: 
     
       1. A purified compound of the following formula Cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester): 
       
         
           
           
               
               
           
         
         wherein n=2 or n=3, having a total content of impurities of lower than 1%, and/or and having a total content of impurities wherein the major impurity is lower than 0.9%, and the chromatographic assay of the purified compound cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester) exhibits a content of the purified compound cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester) of higher than 97.5%, and/or a salt thereof. 
       
     
     
       2. The purified compound of  claim 1 , wherein n=3. 
     
     
       3. The purified compound of  claim 1 , wherein n=2. 
     
     
       4. A purified crystalline compound of the formula: 
       
         
           
           
               
               
           
         
         wherein n=2 or n=3, having substantially the same DSC curve as set out in FIG.  1 . 
       
     
     
       5. A purified crystalline compound of the formula Crystalline cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester): 
       
         
           
           
               
               
           
         
         wherein n=2 or n=3, having substantially the same X-ray diffractogram as set out in  FIG. 2 , and substantially the same IR spectrum, in KBr, as set out in  FIG. 3 characterized by an X-ray powder diffractogram pattern comprising at least one peak chosen from peaks at approximately 7.9, 9.2, and 10.9 degrees 2-theta and having a total content of impurities of lower than 1%. 
       
     
     
       6. A purified crystalline compound of the formula Crystalline cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester): 
       
         
           
           
               
               
           
         
       
       wherein n=2 or n=3, having substantially the same DSC curve as set out in  FIG. 1 , substantially the same X-ray diffractogram as set out in  FIG. 2 , and substantially the same IR spectrum, in KBr, as set out in  FIG. 3 characterized by an X-ray powder diffractogram pattern comprising at least one peak chosen from peaks at approximately 7.9, 9.2, and 10.9 degrees 2-theta and having a total content of impurities of lower than 1% and having a total content of impurities wherein the major impurity is lower than 0.9%. 
     
     
       7. A purified crystalline compound of the formula Crystalline cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester): 
       
         
           
           
               
               
           
         
         wherein n=2 or n=3, having substantially the same DSC curve as set out in  FIG. 4 according to claim 6 containing greater than 97.5% of cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester) by analytical HPLC assay. 
       
     
     
       8. A purified crystalline compound of the formula: 
       
         
           
           
               
               
           
         
         wherein n=2 or n=3, having substantially the same IR spectrum, in KBr, as set out in FIG.  5 . 
       
     
     
       9. A purified crystalline compound of the formula: 
       
         
           
           
               
               
           
         
         wherein n=2 or n=3, having substantially the same DSC curve as set out in  FIG. 4 , and substantially the same IR spectrum, in KBr, as set out in FIG.  5 . 
       
     
     
       10. The purified compound of  claim 1 , wherein said purified compound is present in tautomeric forms and salts thereof. 
     
     
       11. The purified compound of  claim 1 , wherein said purified compound is an enantiomer and the total content of impurities includes the other enantiomeric forms. 
     
     
       12. A pharmaceutical composition comprising an effective amount of one or more purified compounds according to  claim 1 , together with cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester): 
       
         
           
           
               
               
           
         
       
       having a total content of impurities of lower than 1% and having a total content of impurities wherein the major impurity is lower than 0.9% and containing greater than 97.5% of cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester) by analytical HPLC assay and/or a pharmaceutically acceptable salt thereof, together with  and at least one or more pharmaceutically acceptable inactive component chosen from carriers, excipients, adjuvants, and diluents. 
     
     
       13. The pharmaceutical composition of  claim 12 , wherein said pharmaceutically acceptable inactive component is selected from the group consisting of carriers, excipients, adjuvants and diluents. 
     
     
       14. A pharmaceutical composition comprising an effective amount of one or more purified compounds according to  claim 2 , together with one or more pharmaceutically acceptable inactive components. 
     
     
       15. A pharmaceutical composition comprising an effective amount of one or more purified compounds according to  claim 3 , together with one or more pharmaceutically acceptable inactive components. 
     
     
       16. A pharmaceutical composition comprising an effective amount of one or more purified crystalline compounds according to  claim 5 , together with one or more pharmaceutically acceptable inactive components. 
     
     
       17. A pharmaceutical composition comprising an effective amount of one or more purified crystalline compounds according to  claim 6 , together with one or more pharmaceutically acceptable inactive components. 
     
     
       18. A pharmaceutical composition comprising an effective amount of one or more purified crystalline compounds according to  claim 9 , together with one or more pharmaceutically acceptable inactive components. 
     
     
       19. A method for treatment of a mammalian parasitic disease comprising administering to a patient in need of such treatment an effective amount of a purified compound as defined in  claim 1  for treatment of said parasitic disease. 
     
     
       20. A method for immunosuppressive therapy comprising administering to a patient in need of such therapy an effective amount of a purified compound as defined in  claim 1  for said immunosuppressive therapy. 
     
     
       21. A method for the treatment of leukemia comprising administering to a patient in recognized need of such therapy an effective amount of a purified compound as defined in  claim 1  for treatment of said leukemia cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester): 
       
         
           
           
               
               
           
         
       
       having a total content of impurities of lower than 1% and having a total content of impurities wherein the major impurity is lower than 0.9% and containing greater than 97.5% of cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester) by analytical HPLC assay, and/or a pharmaceutically acceptable salt thereof. 
     
     
       22. The A method according to  claim 21 , wherein said leukemia is selected from the group consisting of for the treatment of acute myeloid leukemia (AML), myelodysplastic syndrome (MDS) and, and/or myeloproliferative disorders comprising administering to a patient in recognized need of such treatment cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester): 
       
         
           
           
               
               
           
         
       
       having a total content of impurities of lower than 1% and having a total content of impurities wherein the major impurity is lower than 0.9% and containing greater than 97.5% of cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester) by analytical HPLC assay, and/or a pharmaceutically acceptable salt thereof. 
     
     
       23. The A method according to  claim 22 , wherein said myeloproliferative disorder is for the treatment of chronic myelogenous leukemia comprising administering to a patient in recognized need of such treatment cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester): 
       
         
           
           
               
               
           
         
       
       having a total content of impurities of lower than 1% and having a total content of impurities wherein the major impurity is lower than 0.9% and containing greater than 97.5% of cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester) by analytical HPLC assay, and/or a pharmaceutically acceptable salt thereof. 
     
     
       24. The method according to  claim 21 , wherein said purified compound is administered as an adjuvent therapy of resistance to other chemotherapeutic agents. 
     
     
       25. The method according to claim  21  23, wherein said purified compound cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester), and/or pharmaceutically acceptable salt thereof, is administered by a parenteral mode of administration. 
     
     
       26. The method according to  claim 21 , wherein said purified compound is administered by an oral mode of administration. 
     
     
       27. The method according to  claim 21 , wherein said purified compound is administered by an anal administration. 
     
     
       28. The method according to  claim 21 , wherein said purified compound is administered by a topical mode of administration. 
     
     
       29. The method according to  claim 26 , wherein said parenteral mode of administration is subcutaneous. 
     
     
       30. The cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester): 
       
         
           
           
               
               
           
         
       
       and/or salt thereof according to claim 1 wherein said cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester) and/or salt thereof is semi-synthetic or synthetic.  
     
     
       31. A pharmaceutical composition comprising semi-synthetic and/or synthetic cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester): 
       
         
           
           
               
               
           
         
       
       having a total content of impurities wherein the major impurity is lower than 0.9%, and/or a pharmaceutically acceptable salt thereof, and at least one pharmaceutically acceptable inactive component selected from carriers, excipients, adjuvants, and diluents.  
     
     
       32. The cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester) according to claim 5 wherein said cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester) is semi-synthetic.  
     
     
       33. A salt of cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester): 
       
         
           
           
               
               
           
         
       
       comprising cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester) having a total content of impurities of lower than 1% and/or having a total content of impurities wherein the major impurity is lower than 0.9%.  
     
     
       34. A pharmaceutical composition comprising semi-synthetic and/or synthetic cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester): 
       
         
           
           
               
               
           
         
       
       having a total content of impurities of lower than about 1%, and/or a pharmaceutically acceptable salt thereof, and at least one pharmaceutically acceptable inactive component selected from carriers, excipients, adjuvants, and diluents.  
     
     
       35. A pharmaceutical composition comprising cephalotaxine, 4-methyl (2′R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl) butanedioate (ester): 
       
         
           
           
               
               
           
         
       
       having a total content of impurities of lower than 1% and having a total content of impurities wherein the major impurity is lower than 0.9%, and/or a pharmaceutically acceptable salt thereof, and at least one pharmaceutically acceptable inactive component selected from carriers, excipients, adjuvants, and diluents.