Polymorphic form of Granisetron base, methods for obtaining it and formulation containing it

摘要

Relates to a new polymorphic form of Granisetron base, Form I, to methods for obtaining thereof, to the method for obtaining Granisetron.HCl and its use for preparing pharmaceutical formulations. The Form I is characterized by the X-ray powder diffractogram shown in FIG. 1. Included in summarised form are the methods and solvents for obtaining the Form I: 1) Evaporation of hexane at atmospheric pressure; 2) Evaporation of acetone at atmospheric pressure; 3) Evaporation of toluene at atmospheric pressure; 4) Cooling of a saturated solution of diethyl ether to reflux temperature; 5) Evaporation of 2-propanol atmospheric pressure; 6) Evaporation of tetrahydrofuran at atmospheric pressure; and 7) Cooling of a saturated solution of acetonitrile to reflux temperature.