Dihydrate of benzothiophene compound or of a salt thereof, and process for producing the same

A process for producing a dihydrate of 7-[4-(4-benzo[b]thiophen-4-yl-piperazin-1-yl)butoxy]-1H-quinolin-2-one or of a salt thereof,

• the process comprising:
• (1) mixing at least one organic acid selected from the group consisting of acetic acid and lactic acid, an ethanol-water mixed solution, and 7-[4-(4-benzo[b]thiophen-4-yl-piperazin-1-yl)butoxy]-1H-quinolin-2-one to prepare an acid solution;
• (2) cooling the solution obtained in step (1) to 5° C. or less;
• and
• (3) mixing the solution cooled in step (2) with an alkali to adjust the pH of the solution to 7 or more.

A dihydrate of 7-[4-(4-benzo[b]thiophen-r-yl-piperazin-1-yl)butoxy]-1H-quinolin-2-one, wherein has at least two of the following:

• (a) characteristic peaks at diffraction angles (2θ) of 8.1°, 8.9°, 15.1°, 15.6°, and 24.4° in an X-ray powder diffraction pattern measured by copper radiation of λ=1.5418 Å through a monochromator;
• (b) characteristic peaks at 3509 cm−1, 2934 cm−1, 2812 cm−1, 1651 cm−1, 1626 cm−1, 1447 cm−1, 1223 cm−1, and 839 cm−1 in an infrared absorption spectrum as measured by a potassium bromide tablet method;
• (c) characteristic peaks at 1497 cm−1, 1376 cm−1, 1323 cm−1, 1311 cm−1, 1287 cm−1, 1223 cm−1, and 781 cm−1 in a Raman spectrum;
• (d) peaks in a 1H-NMR spectrum at:
• 1.64 ppm (tt, J=7.4 Hz, J=7.4 Hz, 2H),
• 1.80 ppm (tt, J=7.0 Hz, J=7.0 Hz, 2H),
• 2.44 ppm (t, J=7.5 Hz, 2H),
• 2.62 ppm (br, 4H),
• 3.06 ppm (br, 4H),
• 3.32 ppm (s, 4H+H2O),
• 4.06 ppm (t, J=6.5 Hz, 2H),
• 6.29 ppm (d, J=9.5 Hz, 1H),
• 6.80 ppm (d, J=2.5 Hz, 1H),
• 6.80 ppm (dd, J=2.5 Hz, J=9.0 Hz, 1H),
• 6.88 ppm (d, J=7.5 Hz, 1H),
• 7.27 ppm (dd, J=7.8 Hz, J=7.8 z, 1H),
• 7.40 ppm (dd, J=0.5 Hz, J=5.5 Hz, 1H),
• 7.55 ppm (d, J=9.0 Hz, 1H),
• 7.61 ppm (d, J=8.0 Hz, 1H),
• 7.69 ppm (d, J=5.5 Hz, 1H),
• 7.80 ppm (d, J=9.5 Hz, 1H), and
• 11.57 ppm (s, 1H).