申请人:Miki Takashi
公开号:US20110152572A1
公开(公告)日:2011-06-23
Provided is a new crystal A of optically active 4-amino-3-(4-chlorophenyl)butanoic acid which is far better in stability, and a process for producing the crystal and a process for producing the crystal A comprising a step of heating the following crystal B in water having a pH of 3 to 9:
crystal A:
a crystal of optically active 4-amino-3-(4-chlorophenyl)butanoic acid which has diffraction peaks within the range of a diffraction angle 2θ of 8.7 to 9.4°, within that of 2θ of 12.2 to 12.8°, and within that of 2θ of 24.8 to 25.4° in a powder X-ray diffraction measurement of the crystal by use of the Cu—Kα wavelength; and
crystal B:
a crystal of optically active 4-amino-3-(4-chlorophenyl)butanoic acid which has diffraction peaks within the range of a diffraction angle 2θ of 20.8 to 21.4°, within that of 2θ of 26.7 to 27.3°, and within that of 2θ of 29.7 to 30.3° in a powder X-ray diffraction measurement of the crystal by use of the Cu—Kα wavelength.
提供了一种新的具有光学活性的4-氨基-3-(4-氯苯基)丁酸晶体A,其稳定性更好,以及生产该晶体的方法和生产晶体A的方法,包括在具有pH值为3至9的水中加热以下晶体B的步骤:
晶体A:一种具有光学活性的4-氨基-3-(4-氯苯基)丁酸晶体,其在Cu-Kα波长下通过粉末X射线衍射测量具有在8.7至9.4°的衍射角2θ范围内、在12.2至12.8°的2θ范围内、以及在24.8至25.4°的2θ范围内的衍射峰;
晶体B:一种具有光学活性的4-氨基-3-(4-氯苯基)丁酸晶体,其在Cu-Kα波长下通过粉末X射线衍射测量具有在20.8至21.4°的衍射角2θ范围内、在26.7至27.3°的2θ范围内、以及在29.7至30.3°的2θ范围内的衍射峰。