title: Chromatographic separation of free dafachronic acid epimers with a novel triazole click quinidine-based chiral stationary phase.
abstract: For the first time, a successful chromatographic method based on the use of a novel triazole click quinidine (QD) derivative anion-exchange chiral stationary phase (CSP) is applied for the epimer separation of dafachronic acids (Δ(4)- and Δ(7)-DAs). The use of a polar-ionic eluent system consisting of 18mM AcOH in ACN furnished an excellent separation of both Δ(4)- (α=1.19, RS=2.52) and Δ(7)-DA (α=1.14, RS=2.06) C-25 epimer couples. The pool of data collected during the chromatographic analyses revealed the prominent role of anion-exchange interactions in governing the analyte (SA) retention and also indicated the occurrence of stereoselective H-bond contacts with the chiral selector (SO) substructural motifs. In any case, molecular modelling studies corroborate the need for sufficient spatial freedom for optimum binding between the SO and the SAs which seems less the case for the immobilised SO unit of the commercialized QD-based CSP.
authors.affiliation: Department of Pharmaceutical Sciences, University of Perugia, Via Fabretti 48, 06123 Perugia, Italy.
authors.forename: Roccaldo
authors.initials: R
authors.lastname: Sardella
authors.affiliation: Department of Pharmaceutical Sciences, University of Perugia, Via Fabretti 48, 06123 Perugia, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Carotti
authors.affiliation: Department of Pharmaceutical Sciences, University of Perugia, Via Fabretti 48, 06123 Perugia, Italy.
authors.forename: Antimo
authors.initials: A
authors.lastname: Gioiello
authors.affiliation: Department of Pharmaceutical Sciences, University of Perugia, Via Fabretti 48, 06123 Perugia, Italy.
authors.forename: Antonella
authors.initials: A
authors.lastname: Lisanti
authors.affiliation: Department of Pharmaceutical Sciences, University of Perugia, Via Fabretti 48, 06123 Perugia, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Ianni
authors.affiliation: Department of Analytical Chemistry, University of Vienna, Währinger Strasse 38, 1090 Vienna, Austria.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Lindner
authors.affiliation: Department of Pharmaceutical Sciences, University of Perugia, Via Fabretti 48, 06123 Perugia, Italy. Electronic address: benedetto.natalini@unipg.it.
authors.forename: Benedetto
authors.initials: B
authors.lastname: Natalini
mesh_terms: D002782:Cholestenes / Q000737:chemistry / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D007475:Ion Exchange Resins; D008958:Models, Molecular; D011802:Quinidine; D013237:Stereoisomerism; D013816:Thermodynamics; D014230:Triazoles / Q000737:chemistry*
chemical_list: D002782:Cholestenes; D007475:Ion Exchange Resins; D014230:Triazoles; C533800:dafachronic acid; D011802:Quinidine
keywords: Click triazole quinidine-based stationary phases; Dafachronic acids; Epimer separation; Mechanism of recognition; Molecular dynamic simulations