ABSTRACT
The isolation of milligram amounts of the enantiomers of a benzodiazepinone derivative was performed on an analytical cellulose tribenzoate-based column by multiple repetitive injections. An enantiomeric purity greater than 98% was required. First, an analytical method was developed to maximize the resolution by adjusting the mobile phase composition, flow-rate and most importantly the column temperature. Then the preparative separation was optimized by adjusting the sample size and detecting the sample where its UV absorbance was low. The locations of the cut points were determined by use of detector response levels. The method development, preparative separations and analytical assays of the fractions obtained were all performed on analytical columns.
Subject(s)
Benzodiazepinones/isolation & purification , Chromatography, High Pressure Liquid , Spectrophotometry, Ultraviolet , StereoisomerismABSTRACT
The enantiomers of omeprazole and some of its analogues have been separated on a chiral stationary phase comprising trisphenylcarbamoylcellulose coated on 3-aminopropyl silica. The nature of the supporting silica has a crucial effect on the separations obtained. The racemisation half-life of omeprazole was estimated to be 1.3.10(2) h at 37 degrees C. In vitro tests on isolated gastric glands from rabbits showed that both enantiomers of omeprazole had an inhibitory effect on acid formation.
Subject(s)
Cellulose/analogs & derivatives , Chromatography, High Pressure Liquid/methods , Gastric Acid/metabolism , Gastric Mucosa/drug effects , Omeprazole/isolation & purification , Animals , Gastric Mucosa/metabolism , Half-Life , Omeprazole/chemistry , Omeprazole/pharmacology , Particle Size , Polysaccharides/chemistry , Rabbits , StereoisomerismABSTRACT
A rapid and simple method for the preparation of high-performance liquid chromatography columns for chiral separations is described. The stationary phase is prepared by adsorbing bovine serum albumin on silica. Both analytical and preparative applications are described. A polarimeter was used as a detector to determine the enantiomer elution orders.
