title: Structural elucidation of the Rifaximin Ph. Eur. Impurity H.
abstract: Rifaximin, a semisynthetic, rifamycin-based non-systemic antibiotic is used in the treatment of acute and chronic gastrointestinal disorders. The aim of this study was the elucidation of the molecular structure of the 802 Dalton impurity which was found in Rifaximin industrial batches and reported with an erroneous structure in European Pharmacopoeia 6.5 (2009) [7] monograph as Rifaximin Impurity H. This impurity was isolated from Rifaximin by preparative HPLC and purified by column chromatography. The molecular structure was evidenced by means of (1)H and (13)C NMR spectroscopy, mass spectrometry and FT-IR.
authors.affiliation: DISMAB - Sezione di Chimica Organica "A.Marchesini", Università degli Studi, Milano, Italy. riccardo.stradi@unimi.it
authors.forename: Riccardo
authors.initials: R
authors.lastname: Stradi
authors.forename: Donatella
authors.initials: D
authors.lastname: Nava
authors.forename: Marino
authors.initials: M
authors.lastname: Nebuloni
authors.forename: Barbara
authors.initials: B
authors.lastname: Pastura
authors.forename: Elena
authors.initials: E
authors.lastname: Pini
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D004340:Drug Contamination; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010602:Pharmacopoeias as Topic; D012294:Rifamycins / Q000737:chemistry*; D000078262:Rifaximin; D021241:Spectrometry, Mass, Electrospray Ionization; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013678:Technology, Pharmaceutical / Q000379:methods
chemical_list: D000900:Anti-Bacterial Agents; D012294:Rifamycins; D000078262:Rifaximin