Crystalline forms of tigecycline hydrochloride

Abstract

The present invention relates to crystalline forms A and B of Tigecycline hydrochloride and to methods for the preparation of the same. Furthermore the present invention relates to the use of crystalline forms A and B of Tigecycline hydrochloride as intermediates for the formulation of an anti-infective medicament. Moreover the present invention relates to pharmaceutical compositions comprising crystalline form A of Tigecycline hydrochloride in an effective amount and to the use of crystalline form A of Tigecycline hydrochloride as anti-infective medicament.

1 - 36 . (canceled) 
     
     
         37 . Crystalline Tigecycline hydrochloride 
     
     
         38 . A crystalline form A of Tigecycline hydrochloride. 
     
     
         39 . The crystalline form A of Tigecycline hydrochloride according to  claim 38 , having wherein the crystalline form A is a monohydrochloride. 
     
     
         40 . The crystalline form A of Tigecycline hydrochloride according to  claim 38 , wherein the water content of the crystalline form A ranges from about 0 to 6.0%. 
     
     
         41 . The crystalline form A of Tigecycline hydrochloride according to  claim 38 , containing less than 10% of form B or amorphous Tigecycline. 
     
     
         42 . The crystalline form A of Tigecycline hydrochloride according to  claim 38 , containing less than 5% of form B or amorphous Tigecycline. 
     
     
         43 . The crystalline form A of Tigecycline hydrochloride according to  claim 38 , containing less than 1% of form B or amorphous Tigecycline. 
     
     
         44 . The crystalline form A of Tigecycline hydrochloride according to  claim 38 , the crystalline form A is an essentially pure polymorphic form. 
     
     
         45 . The crystalline form A of Tigecycline hydrochloride according to  claim 38 , having enhanced water solubility compared to forms I to V of Tigecycline. 
     
     
         46 . The crystalline form A of Tigecycline hydrochloride according to  claim 38 , having enhanced storage stability compared to forms Ito III and amorphous Tigecycline. 
     
     
         47 . A process for the preparation of crystalline form A of Tigecycline hydrochloride, comprising the steps of:
 a) stirring a suspension of Tigecycline in a suitable solvent at room temperature to form a suspension;   b) adding hydrochloric acid to the suspension; and   c) isolating crystalline form A of Tigecycline hydrochloride.   
     
     
         48 . A process for the preparation of crystalline form A of Tigecycline hydrochloride, comprising the steps of:
 a) dissolving Tigecycline in a suitable solvent at a temperature ranging from room temperature to the boiling point of the used solvent to form a solution;   b) adding hydrochloric acid to the solution of step a), wherein a precipitate forms to form a suspension;   c) cooling down the suspension to room temperature or below; and   d) isolating crystalline form A of Tigecycline hydrochloride.   
     
     
         49 . A method of using crystalline form A of Tigecycline hydrochloride as an anti-infective medicament comprising treating a patient with an effective amount of crystalline form A of Tigecycline hydrochloride. 
     
     
         50 . A pharmaceutical composition formed from an effective amount of crystalline form A of Tigecycline hydrochloride. 
     
     
         51 . A crystalline form B of Tigecycline hydrochloride.