Process for the preparation of an optically active 5H-pyrrolo [3,4-B] pyrazine derivative
A substantially pure dextrorotatory isomer of zopiclone or a pharmaceutically acceptable salt thereof and crystalline forms thereof are provided. Also provided is a process for its preparation and pharmaceutical compositions containing same.
1. A crystalline form of a dextrorotatory isomer of zopiclone, characterized as having an X-ray diffraction pattern in accordance with FIG. 2 .
2. A pharmaceutical composition comprising a therapeutically effective amount of the crystalline form of the dextrorotatory isomer of zopiclone of claim 1 and at least one pharmaceutically acceptable carrier, diluent or excipient.
3. The pharmaceutical composition of claim 2 , wherein the crystalline form of the dextrorotatory isomer of zopiclone is a micronized crystalline form of the dextrorotatory isomer of zopiclone having a particle size distribution equal to or less than about 200 microns.
4. The pharmaceutical composition of claim 2 , wherein the crystalline form of the dextrorotatory isomer of zopiclone is a micronized crystalline form of the dextrorotatory isomer of zopiclone having a particle size distribution equal to or less than about 150 microns.
5. The pharmaceutical composition of claim 2 , wherein the crystalline form of the dextrorotatory isomer of zopiclone is a micronized crystalline form of the dextrorotatory isomer of zopiclone having a particle size distribution equal to or less than about 50 microns.
6. The pharmaceutical composition of claim 2 , wherein the crystalline form of the dextrorotatory isomer of zopiclone is a micronized crystalline form of the dextrorotatory isomer of zopiclone having a particle size distribution equal to or less than about 15 microns.
7. The pharmaceutical composition of claim 2 , which is in a solid form.
8. The pharmaceutical composition of claim 2 , which is a tablet or capsule.