title: Analytical and semipreparative high performance liquid chromatography enantioseparation of bicalutamide and its chiral impurities on an immobilized polysaccharide-based chiral stationary phase.
abstract: Direct HPLC separation of enantiomers of Bicalutamide (BCT), a non-steroidal antiandrogen used for the treatment of prostate cancer, was performed by using the immobilized amylose-based Chiralpak IA chiral stationary phase (CSP). Enantioselective conditions were achieved using standard normal phase mixtures n-hexane-alcohol (ethanol or 2-propanol) and a "non-standard" mobile phase containing ethyl acetate (EA). The chromatographic behaviour of the IA CSP under these elution modes was evaluated and compared at different temperatures. The eluent mixture n-hexane-EA-ethanol 100-30-5 (v/v/v) and the column temperature of 40°C were identified as the best operational conditions to carry out semipreparative enantioseparations on a 1-cm I.D. IA column. Using this protocol, about 960mg of (R)-BCT, which is the enantiomer with the almost entire anti-androgenic activity of BCT, per day could be isolated. The analytical and semipreparative HPLC resolution of chiral impurities of BCT, and their empiric absolute configuration assignment by circular dichroism correlation method are also presented.
authors.affiliation: Dipartimento del Farmaco, Istituto Superiore di Sanità, Viale Regina Elena 299, I-00161 Rome, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Sadutto
authors.affiliation: Dipartimento del Farmaco, Istituto Superiore di Sanità, Viale Regina Elena 299, I-00161 Rome, Italy.
authors.forename: Rosella
authors.initials: R
authors.lastname: Ferretti
authors.affiliation: Dipartimento del Farmaco, Istituto Superiore di Sanità, Viale Regina Elena 299, I-00161 Rome, Italy.
authors.forename: Leo
authors.initials: L
authors.lastname: Zanitti
authors.affiliation: Dipartimento di Malattie Infettive, Parassitarie ed Immunomediate, Istituto Superiore di Sanità, Viale Regina Elena 299, I-00161 Rome, Italy.
authors.forename: Adriano
authors.initials: A
authors.lastname: Casulli
authors.affiliation: Dipartimento del Farmaco, Istituto Superiore di Sanità, Viale Regina Elena 299, I-00161 Rome, Italy. Electronic address: rcirilli@iss.it.
authors.forename: Roberto
authors.initials: R
authors.lastname: Cirilli
mesh_terms: D019840:2-Propanol / Q000737:chemistry; D000688:Amylose / Q000737:chemistry; D000813:Anilides / Q000032:analysis* / Q000737:chemistry; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D002942:Circular Dichroism; D000431:Ethanol / Q000737:chemistry; D006586:Hexanes / Q000737:chemistry; D009570:Nitriles / Q000032:analysis* / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry*; D013237:Stereoisomerism; D014105:Tosyl Compounds / Q000032:analysis* / Q000737:chemistry
chemical_list: D000813:Anilides; D006586:Hexanes; D009570:Nitriles; D011134:Polysaccharides; D014105:Tosyl Compounds; C026385:n-hexane; D000431:Ethanol; D000688:Amylose; C053541:bicalutamide; D019840:2-Propanol
keywords: Bicalutamide; Chiralpak IA; Enantiomers; Impurities; Semipreparative resolution; Temperature-variable HPLC