title: Liquid chromatographic method for enantiopurity control of alaptide using polysaccharide stationary phases.
abstract: Separation of veterinary drug alaptide ((S)-8-methyl-6,9-diazaspiro(4,5)decane-7,10-dione) from a chiral impurity (R-enantiomer) was developed. Five chiral columns (three amylose and two cellulose type) were evaluated in a reversed-phase system. Three of them offered satisfactory enantiomeric resolution. Finally, three methods were validated and proved to be applicable for the determination of a chiral impurity content below 0.1% (method A: 3-AmyCoat column, tris-[3,5-dimethylphenyl]carbamoyl amylose; mobile phase: water/methanol/propan-2-ol/butan-2-ol=75:20:3.5:1.5 v/v, flow rate: 0.40 mL/min; column temperature: 30 °C; method B: Chiralpak AS-3R, tris-[1-phenylethyl]carbamoyl amylose; water/acetonitrile=80:20 v/v, 0.40 mL/min; 40 °C; method C: Chiralcel OZ-3R, tris-[3-chloro-4-methylphenyl] carbamoyl cellulose; water/acetonitrile=80:20 v/v, 0.40 mL/min; 40 °C). Some decrease in efficiency with repeated sample injections was observed for the 3-AmyCoat column. The resistance to mass transfer in the stationary phase increased probably due to the change in chiral selector conformation. This effect was considerably suppressed by propan-2-ol or to a greater extent by butan-2-ol added to a mobile phase. Simple regeneration was also suggested to recover efficiency of the column.
authors.affiliation: Zentiva, a.s. Prague, U Kabelovny, Prague, Czech Republic.
authors.forename: Michal
authors.initials: M
authors.lastname: Douša
authors.forename: Karel
authors.initials: K
authors.lastname: Lemr
mesh_terms: D000327:Adsorption; D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods*; D009479:Neuropeptides / Q000737:chemistry*; D010456:Peptides, Cyclic / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D009479:Neuropeptides; D010456:Peptides, Cyclic; D011134:Polysaccharides; C049178:cyclo(alanine-(1-amino-1-cyclopentane)carbonyl)