725719-13-1

N-[2-Hydroxy-5-[(1S)-1-hydroxy-2-[[(1S)-2-(4-methoxyphenyl)-1-methylethyl]amino]ethyl]phenyl]acetamide, is an impurity of Arformoterol Tartrate (A767505) which is a long-acting β2 adrenoreceptor agonist (LABA) indicated for the treatment of chronic obstructive pulmonary disease (COPD).