title: Isolation and identification of a novel impurity of erythromycin A 9-oxime desosaminehydrazinium salt.
abstract: In the manufacturing process for Biaxin (clarithromycin), erythromycin-A oxime, an intermediate, is obtained in high yield, when erythromycin-A is treated with hydroxylamine/isopropyl alcohol in the presence of acetic acid. An unusual impurity, the desosamine hydrazinium salt, is generated in this step of the synthetic pathway, and has been isolated and characterized by using one and two-dimensional NMR spectroscopy in conjunction with MS and EDS.
authors.forename: Casey Chun
authors.initials: CC
authors.lastname: Zhou
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Huang
authors.forename: Kelley L
authors.initials: KL
authors.lastname: Ford
authors.forename: L Steven
authors.initials: LS
authors.lastname: Hollis
mesh_terms: D004917:Erythromycin / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry / Q000302:isolation & purification*; D006834:Hydrazines / Q000138:chemical synthesis / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy
chemical_list: D006834:Hydrazines; C506329:erythromycin A 9-oxime desosaminehydrazinium salt; D004917:Erythromycin