α-form or β-form crystal of acetanilide derivative
View Patent ↗To provide novel crystals useful as an ingredient for the production of a diabetes remedy. The invention is concerned with α-form crystal and β-form crystal of (R)-2-(2-aminothiazol-4-yl)-4′-[2-[(2-hydroxy-2-phenyleth-yl)amino]ethyl]acetanilide. The α-form crystal does not exhibit hygroscopicity and has stability such that it can be used as a medicine, and is useful for mass synthesis in the industrial production. The β-form crystal does not relatively exhibit hygroscopicity and is also useful as a production intermediate of the α-form crystal.
1. A crystal of (R)-2-(2-aminothiazol-4-yl)-4′-[2-[(2-hydroxy-2-phenylethyl)amino]ethyl]acetanilide having a heat absorption peak at 142 to 146° C. in the DSC analysis and having main peaks at around 5.32, 8.08, 15.28, 17.88, 9.04, 20.20, 23.16 and 24.34 in the terms of 2θ(°) in the powder X-ray diffraction.
2. A crystal of (R)-2-(2-aminothiazol-4-yl)-4′-[2-[(2-hydroxy-2-phenylethyl)amino]ethyl]acetanilide having heat absorption peaks at 90 to 110° C. and at 142 to 146° C. in the DSC analysis and having main peaks at around 9.68, 19.76, 20.72, 22.10 and 23.52 in the terms of 2θ(°) in the powder X-ray diffraction.