title: Semipreparative chiral supercritical fluid chromatography in the fractionation of lansoprazole and two related antiulcer drugs enantiomers.
abstract: The semipreparative chiral separation of lansoprazole and two related compounds (pantoprazole and rabeprazole) using supercritical fluid chromatography (SFC) is presented in this work. Different loads were evaluated in order to obtain high enantiomeric purities and production rates. The volumes injected were 1, 2 and 4 mL. The concentrations of the racemic mixtures were 3 and 6 g/L for lansoprazole and 1.5 g/L for pantoprazole and rabeprazole. In all the cases, the recoveries, for a purity higher than 99.9%, were better for the second eluted enantiomer than for the first one. This fact conditioned the production rate of the first eluted enantiomer that, considering a fixed purity, was always lower than that obtained for the other one. In the case of lansoprazole it was possible to obtain 0.025 and 0.090 mg/min of the first and second eluted enantiomer, respectively, with an enantiomeric purity of 99.9%. For rabeprazole enantiomers 0.037 and 0.062 mg/min, and in the case of pantoprazole the results were better (0.062 and 0.122 mg/min) due to the higher resolution.
authors.affiliation: Department of Analytical Chemistry, Faculty of Science, University of Valladolid, Valladolid, Spain. ltoribio@qa.uva.es
authors.forename: Laura
authors.initials: L
authors.lastname: Toribio
authors.forename: María J
authors.initials: MJ
authors.lastname: del Nozal
authors.forename: Yagüe L
authors.initials: YL
authors.lastname: Bernal
authors.forename: Cristina
authors.initials: C
authors.lastname: Alonso
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Jiménez
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles / Q000032:analysis* / Q000302:isolation & purification; D000897:Anti-Ulcer Agents / Q000494:pharmacology*; D005591:Chemical Fractionation; D002623:Chemistry Techniques, Analytical / Q000379:methods; D002626:Chemistry, Pharmaceutical / Q000379:methods; D002845:Chromatography / Q000379:methods; D025924:Chromatography, Supercritical Fluid / Q000379:methods*; D004867:Equipment Design; D064747:Lansoprazole; D008956:Models, Chemical; D000077402:Pantoprazole; D004364:Pharmaceutical Preparations / Q000302:isolation & purification; D064750:Rabeprazole; D013237:Stereoisomerism; D013997:Time Factors
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000897:Anti-Ulcer Agents; D004364:Pharmaceutical Preparations; D064747:Lansoprazole; D064750:Rabeprazole; D000077402:Pantoprazole