Patent ID: 7008928

Claim:
Crystals of N 2 -(N, N-dimethyl-L-valyl)-N-[(1S, 2R)-2-methoxy-4-[(2S)-2-[(1R, 2R)-1-methoxy-2-methyl-3-oxo-3-[(2-phenylethyl)amino]propyl]-1-pyrrolidinyl]-1-[(S)-1-methylpropyl]-4-oxobutyl]-N-methyl-L-valinamide represented by the following formula (I) or a salt thereof: which crystals have characteristic peaks at the interplanar spacing (d) of 14.72, 12.27, 9.84, 9.28, 8.68, 7.39, 6.11, 5.32, 5.10, 4.90, 4.61, 4.47 and 4.36 Å in their powder X-ray diffraction pattern.