title: Enantiomeric separation of racemic neolignans on chiralcel OD and determination of their absolute configuration with online circular dichroism.
abstract: Effective enantiomeric separations of erythro- and threo-8.O.4'-neolignans with different aromatic substitution pattern (1a-i, 2a-i) are achieved on the commercially available chiral stationary phase cellulose tris(3,5-dimethylphenylcarbamate) (Chiralcel OD). It is shown that the chiral recognition of the stationary phase is significantly dependent on the substitution pattern of the racemic compounds. Online liquid chromatography (LC)-circular dichroism (CD) analysis allows for the establishment of a correlation between the absolute configuration of the separated erythro-8.O.4'-neolignans and their characteristic CD transitions, which could be used to determine or revise the configuration of previously isolated erythro-8.O.4'-neolignans. Although the absolute configurations of threo-isomers is not determined unambiguously from the LC-CD analysis, it is proven that both their elution order and chiroptical properties are significantly influenced by the substitution pattern of the aromatic rings.
authors.affiliation: Department of Organic Chemistry, University of Debrecen, P.O. Box 20, Hungary.
authors.forename: Krisztina
authors.initials: K
authors.lastname: Kónya
authors.forename: Attila
authors.initials: A
authors.lastname: Kiss-Szikszai
authors.forename: Tibor
authors.initials: T
authors.lastname: Kurtán
authors.forename: Sándor
authors.initials: S
authors.lastname: Antus
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002942:Circular Dichroism / Q000379:methods*; D017705:Lignans / Q000737:chemistry / Q000302:isolation & purification*; D013237:Stereoisomerism
chemical_list: D017705:Lignans