Patent ID: 7282505

Claim:
A rapamycin polymorph Form II which contains t-butyl methyl ether solvate molecules having the following characteristics: (a) X-ray diffraction peak pattern comprising peaks at 2θ of about 7.0°, 9.7°, 10.1°, 11.0°, 12.4°, 13.1°, 14.1°, 14.6°, 15.0°, 15.2°, 15.8°, 16.3°, 16.6°, 17.6°, 18.1°, 18.3°, 19.7°, 20.2°, and 21.2°; and (b) a differential scanning calorimetry thermogram having an endotherm peak of about 188°.