azithromycin monohydrate and its Impurities

Azithromycin is a part of the azalide subclass of macrolides, and contains a 15-membered ring, with a methyl-substituted nitrogen instead of a carbonyl group at the 9a position on the aglycone ring, which allows for the prevention of its metabolism.It is primarily used for the treatment of respiratory, enteric and genitourinary infections and may be used instead of other macrolides for some sexually transmitted and enteric infections. Reference standards of Azithromycin Monohydrate API, and its pharmacopeial, non pharmacopeial impurities, and stable isotopes are listed below.