title: [Racemation of the benzodiazepines camazepam and ketazolam and receptor binding of enantiomers].
abstract: The chiral benzodiazepines camazepam (1) and ketazolam (2) were resolved into the enantiomers by chromatography on the optically active adsorbent poly[(S)-N-(1-cyclohexylethyl)-methacrylamide] and fractional crystallisation or repeated chromatography, respectively. The IC50 values of the isomers and of the racemates of both compounds were determined by displacement of radioactively labelled 3H-flunitrazepam and 3H-propyl-beta-carboline-carboxylate from their specific binding sites. (+)-Camazepam exhibits 14fold higher affinity compared to the (-)-enantiomer. In contrast only slight differences in the receptor affinity are observed with the ketazolam enantiomers.
mesh_terms: D000818:Animals; D014151:Anti-Anxiety Agents / Q000378:metabolism*; D001569:Benzodiazepines; D001570:Benzodiazepinones / Q000302:isolation & purification / Q000378:metabolism*; D001667:Binding, Competitive; D001921:Brain / Q000378:metabolism; D005445:Flunitrazepam / Q000378:metabolism; D066298:In Vitro Techniques; D011963:Receptors, GABA-A / Q000378:metabolism*; D013237:Stereoisomerism; D013693:Temazepam / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D014151:Anti-Anxiety Agents; D001570:Benzodiazepinones; D011963:Receptors, GABA-A; D001569:Benzodiazepines; D005445:Flunitrazepam; C002072:ketazolam; D013693:Temazepam
vernacular_title: Razemattrennung der Benzodiazepine Camazepam und Ketazolam und Rezeptorbindung der Enantiomeren.