title: The changing role of ultraviolet spectroscopy in drug analysis.
abstract: New applications in the identification of minor components in drugs by rapid scanning diode-array UV spectrophotometers as high-performance liquid chromatographic (HPLC) detectors are exemplified by (a) identification and quantification of alpha-chloro-4-methoxycinnamic acid methyl ester as the byproduct of the Darzens reaction between 4-methoxybenzaldehyde and chloroacetic acid methyl ester; and (b) identification of 4-androsten-17-one and 3 beta-phenyl-5 alpha-androstan-17-one as impurities in 5 alpha-androst-2-en-17-one. The advantages of the use of derivative spectrophotometry are illustrated by the following examples: (a) determination of flumecinol (3-trifluoromethyl-alpha-ethylbenzhydrol) in an oily emulsion formulation; (b) determination of RGH-6148 (2-benzylthiazolidinone) in a suspension used in toxicological studies; and (c) determination of mestranol as an impurity in norethisterone.
authors.affiliation: Chemical Works of Gedeon Richter Ltd, Budapest, Hungary.
authors.forename: S
authors.initials: S
authors.lastname: Görög
authors.forename: M
authors.initials: M
authors.lastname: Rényei
authors.forename: B
authors.initials: B
authors.lastname: Herényi
mesh_terms: D000736:Androstenes / Q000032:analysis; D001559:Benzhydryl Compounds / Q000032:analysis; D004340:Drug Contamination; D007202:Indicators and Reagents; D008656:Mestranol / Q000032:analysis; D009640:Norethindrone / Q000032:analysis; D004364:Pharmaceutical Preparations / Q000032:analysis* / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet / Q000295:instrumentation*
chemical_list: D000736:Androstenes; D001559:Benzhydryl Compounds; D007202:Indicators and Reagents; D004364:Pharmaceutical Preparations; C069740:androst-2-en-17-one; D008656:Mestranol; C016914:flumecinol; D009640:Norethindrone