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US 2003/0083501 A1Published application
Process for preparing paroxetine HCl which limits formation of pink colored compounds
OwnerIIya Avrutov, Gideon Pilarskyinventors
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OwnerIIya Avrutov, Gideon Pilarskyinventors
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The present invention provides a process for preparing paroxetine HCl from paroxetine base which provides paroxetine HCl substantially free of pink-colored compounds or an impurity identified by an HPLC RRT of about 1.5. The processes of the present invention utilize a buffer, a molar ratio of HCl to paroxetine base of less than one, and crystallize/recrystallize in the presence of an effective amount of an anti-oxidants. A preferred way to create a buffer is by using ammonium chloride. A preferred anti-oxidant is ascorbic acid. The present invention also provides for re-crystalizing paroxetine HCl prepared by the above methods or any other methods in the presence of an effective amount of an anti-oxidant such as ascorbic acid. A preferred solvent system for recrystallization is a mixture of acetone and methanol. Processes of the present invention can combine these various features.
A process for preparing paroxetine HCl comprising reacting paroxetine base with less than about one molar base equivalent of HCl and separating the paroxetine HCl, thereby providing a paroxetine HCl substantially free of pink-colored compounds or the amount of an impurity identified by an HPLC RRT of about 1.5.
A process of preparing paroxetine HCl comprising contacting paroxetine base with HCl at a pH of from about 3 to about 8, and separating the paroxetine HCl, thereby providing a paroxetine HCl substantially free of pink-colored compounds or the amount of an impurity identified by an HPLC RRT of about 1.5.
A process of preparing paroxetine HCl comprising contacting paroxetine base with HCl in a buffer and separating the paroxetine HCl, thereby providing a paroxetine HCl substantially free of pink-colored compounds or the amount of an impurity identified by an HPLC RRT of about 1.5.
A process for preparing paroxetine HCl comprising converting paroxetine base to paroxetine HCl, and separating the paroxetine HCl, wherein at least a portion of the process is carried out in the presence of an effective amount of an anti-oxidant, thereby providing a paroxetine HCl substantially free of pink-colored compounds or the amount of an impurity identified by an HPLC RRT of about 1.5.
A process for preparing paroxetine HCl comprising the steps of:
A process for preparing paroxetine HCl comprising the steps of:
Paroxetine HCl characterized by a having about 0.1% or less of an impurity identified by an HPLC RRT of about 1.5.
Paroxetine HCl characterized by less than about 0.22 of an impurity identified by an HPLC RRT of about 1.5 after storage for at least four days at a temperature of about 55° C., and that upon visual inspection does not appear pink.
Dependencies are inferred from the claim text.