Patent ID: 7259181

Claim:
A β crystalline form of the compound of formula (I): exhibiting essentially the following powder X-ray diffraction data, measured using a diffractometer (copper anticathode) and expressed in terms of inter-planar distance d and Bragg's angle 2 theta: Angle 2 Inter-planar theta (°) distance d (Å) 5.169 17.08 8.379 10.54 9.350 9.45 14.746 6.00 15.411 5.74 15.931 5.56 16.711 5.30 18.161 4.88 20.564 4.32 21.285 4.17 21.781 4.08 22.632 3.93 23.308 3.81 23.797 3.74 24.276 3.66 25.190 3.53 25.924 3.43 26.646 3.34 27.620 3.23 28.306 3.15.