Crystalline Polymorph of acid, 2 - 4 - 2 - (1S, 2R) - 2 - hydroxy - 2 - (4-hydroxyphenyl) - 1-methylethyl amino ethyl phenoxy acetic acid

摘要

Crystal polymorphism of 2-Ä4-Ä2-ÄÄ1s,2RÜ-2-hydroxy-2-(4-hydroxyphenyl)-1-methyl ethylÜaminoÜethylÜphenoxyÜacetic acid which has potent beta 2 adrenergic receptor stimulating and beta 3-adrenergic receptor stimulating effects, is useful in relieving a pain, promoting calculi removal, etc. in urinary lithiasis and shows intense diffraction peaks at 10.8, 19.1, 19.3, 19.8, 20.6 and 27.0 DEG in the powder x-ray diffractometry pattern at a diffraction angle (2/0+/-0.1). It is produced by, for example, hydrolyzing ethyl 2-Ä4-Ä2-ÄÄ1S,2R)-2-hydroxy-2-(4-hydroxyphenyl)-1-methylethylÜaminoÜeth yÜphenoxyÜacetate phosphate by using sodium hydroxide, adding an aqueous solution of phosphoric acid at 40 DEG C or above to give the above compound, adding a solvent mixture comprising methanol with water or methanol and then stirring in a suspended state at from 40 DEG C to the reflux point for 30 minutes to several hours.