title: Estimation of impurity profiles of drugs and related materials. Part VIII: Combined application of high-performance liquid chromatography and NMR spectroscopy in the impurity profiling of drugs.
abstract: The usefulness of the joint application of HPLC and NMR spectroscopy in drug impurity profiling is demonstrated by the following examples: (1) identification of Z and E isomers of 17 alpha-ethynyl-4-oestrene-3 beta, 17-diol-3-acetate-17-(3'-acetoxy-2'-butenoate) in ethynodiol diacetate; (2) identification of the p-tolyl analogue as the impurity of enalapril maleate; (3) identification and quantification of 2'-dehydro-pipecuronium bromide in pipecuronium bromide. The possibilities of utilizing NMR spectroscopy for the identification and quantification of the impurities with and without their isolation are discussed.
authors.affiliation: Chemical Works of Gedeon Richter Ltd, Budapest, Hungary.
authors.forename: S
authors.initials: S
authors.lastname: Görög
authors.forename: G
authors.initials: G
authors.lastname: Balogh
authors.forename: M
authors.initials: M
authors.lastname: Gazdag
mesh_terms: D015113:Androstane-3,17-diol / Q000031:analogs & derivatives* / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D004656:Enalapril / Q000031:analogs & derivatives / Q000032:analysis*; D005040:Ethynodiol Diacetate / Q000031:analogs & derivatives / Q000032:analysis*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009466:Neuromuscular Blocking Agents / Q000032:analysis*; D017300:Pipecuronium / Q000031:analogs & derivatives; D010879:Piperazines / Q000032:analysis*; D013237:Stereoisomerism
chemical_list: D009466:Neuromuscular Blocking Agents; D010879:Piperazines; C075795:2'-dehydropipecuronium; C075880:17-ethynyl-4-estrene-3,17-diol-3-acetate-17-(3'-acetoxy-2'-butenoate); D017300:Pipecuronium; D015113:Androstane-3,17-diol; D005040:Ethynodiol Diacetate; D004656:Enalapril