Cyanopindolol Hemifumarate and its Impurities

Cyanopindolol hemifumarate is a 5-HT1A/1B antagonist with roughly equal affinity at each receptor, also a β-adrenoceptor antagonist. Reference standards of Cyanopindolol Hemifumarate API, and its pharmacopeial, non pharmacopeial impurities, and stable isotopes are listed below.