| abstract |
PROBLEM TO BE SOLVED: To provide a potent agent for ameliorating pain and excretion of urinary calculi, which has a potent β 2 -adrenoceptor stimulating action and β 3 -adrenoceptor stimulating action. [4- [2-[[(1S, 2R) -2-hydroxy-2- (4 -Hydroxyphenyl) -1-methylethyl] amino] A crystalline polymorph of [ethyl] phenoxy] acetic acid dihydrate is provided. SOLUTION: In a powder X-ray diffraction pattern, a diffraction angle (2θ ± 0.1) a polymorph exhibiting strong diffraction peaks at 10.2, 12.7, 18.4 and 22.3 degrees. 2- [4 -[2-[[(1S, 2R) -2-hydroxy-2- (4-Hydroxyphenyl) -1-methylethyl] amino] ethyl] phenoxy] acetic acid was dissolved in a mixed solvent of water and methanol (volume ratio 7: 3 to 9: 1), and concentrated under reduced pressure. The precipitated crystals are dried at room temperature for several hours to several days to produce. |