title: Direct HPLC enantioseparation of chiral aptazepine derivatives on coated and immobilized polysaccharide-based chiral stationary phases.
abstract: The direct HPLC enantioseparation of Mianserin and a series of aptazepine derivatives is accomplished on polysaccharide-based chiral stationary phases (CSPs). The resolutions are performed on the coated-type Chiralcel OD and Chiralpak AD CSPs and on the first commercially available immobilized-type Chiralpak IA CSP, in normal-phase and polar-organic modes. The complete separation of enantiomers of all racemates investigated was successfully achieved under at least one of CSP/eluent combinations employed. Pure alcohols such ethanol or 2-propanol, with a fixed percentage of DEA added, serve as valuable alternatives to the more common n-hexane-based normal-phase eluents in resolution of Mianserin on the AD CSP. In order to study the chiroptical properties of aptazepine derivatives, chromatographic resolutions are carried out at semipreparative scale using Chiralpak AD and Chiralpak IA as CSPs. Nonconventional dichloromethane-based eluents have permitted to expand the chiral resolving ability of the immobilized Chiralpak IA CSP and to perform mg-scale enantioseparations with an analytical-size column. Assignment of the absolute configuration of the separated enantiomers is empirically established by comparing their chiroptical data with those of structurally related Mianserin.
authors.affiliation: Istituto Superiore di Sanità, Dipartimento del Farmaco, Rome, Italy. rcirilli@iss.it
authors.forename: Roberto
authors.initials: R
authors.lastname: Cirilli
authors.forename: Viviana
authors.initials: V
authors.lastname: Orlando
authors.forename: Rosella
authors.initials: R
authors.lastname: Ferretti
authors.forename: Luciana
authors.initials: L
authors.lastname: Turchetto
authors.forename: Romano
authors.initials: R
authors.lastname: Silvestri
authors.forename: Gabriella
authors.initials: G
authors.lastname: De Martino
authors.forename: Francesco
authors.initials: F
authors.lastname: La Torre
mesh_terms: D000688:Amylose / Q000031:analogs & derivatives / Q000737:chemistry; D001569:Benzodiazepines / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D000431:Ethanol / Q000737:chemistry; D000432:Methanol / Q000737:chemistry; D015394:Molecular Structure; D048448:Phenylcarbamates / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D048448:Phenylcarbamates; D011134:Polysaccharides; D001569:Benzodiazepines; C080033:Chiralpak AD; C037604:aptazapine; D000431:Ethanol; D000688:Amylose; D000432:Methanol