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Showing 1 to 20 of 25 for “"chiral stationary phases"”.
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Synthetic Chiral Stationary Phases in Enantioselective Liquid Chromatography
… to edge interactions on a particular type of chiral stationary phase (CSP) used for chromatographic separations of enantiomers has been studied. Highly polarizable aromatic substituents, such as halogens, have been found to enhance $\pi - \pi$ face to face interactions and can be used in the …
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Design, Synthesis, and Applications of Chiral Stationary Phases
… separation of the enantiomers upon a chiral stationary phase. The aim of this research was to develop efficient and widely useful chiral stationary phases. Our approach to this problem was to synthesize a series of specific chiral compounds containing three sites for potential use in …
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Investigations of chiral recognition of conformationally rigid chiral stationary phases
… the development of conformationally rigid chiral stationary phases (CSPs) has been a goal. Several conformationally rigid CSPs derived from $\alpha$-amino-lactams have been prepared and their abilities to separate the enantiomers of a variety of analytes have been evaluated. $\pi$-Acidic …
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Applications of Brush-Type Chiral Stationary Phases in New Chromatographic Techniques
… are an important class of resolutions by which a chiral stationary phase (CSP) is utilized to affect the separation of a mixture of enantiomers to provide, as the end result, the single enantiomers of the mixture. In the studies described within, three areas involved in chiral discrimination are …
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Preparation and evaluation of several new pi-basic chiral stationary phases
Several new chiral stationary phases (CSPs) derived from $\alpha$-arylalkylamines and N-arylamino acids are evaluated based on their chromatographic performance. These new chiral stationary phases are useful for separation of the enantiomers of N-(3,5-dinitrobenzoyl) derivatized $\alpha$- and …
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A Rational Approach to the Design of Highly Effective Chiral Stationary Phases
… on a chromatography column containing a chiral stationary phase is emerging as an outstanding technique for the determination of enantiomeric purity, the assignment of absolute configuration and the preparative resolution of enantiomers. The continued growth of this technique depends upon …
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Characterization of pi-donor chiral stationary phases through a thermodynamic study of analyte adsorption
"Liquid chromatography on several $\pi$-donor chiral stationary phases (CSP's) at different temperatures allows determination of the values of $\Delta$H and $\Delta$S of adsorption. A homologous series of N,N$\sp\prime$-di(2,4-dinitrophenyl)$\alpha$,$\omega$-diaminoalkanes (di DNP amines) was …
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Synthesis and evaluation of N-3,5-dinitrobenzoyl-beta-amino acid derived chiral stationary phases
The use of chiral stationary phases (CSPs) for the direct analytical and preparative separation of enantiomers has enjoyed increasing popularity in the past decade. The inherent advantages of chromatography; rapid analysis time, the ability to separate complex mixtures, reproducibility, flexibility …
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Direct Liquid Chromatographic Separation of Enantiomers of Phthalides, Phthalimidines and Related Compounds on Chiral Stationary Phases
… by high performance liquid chromatography on chiral stationary phases (CSPs) derived from the N-3,5-dinitrobenzamides of (S)-leucine or (R)-phenylglycine covalently bonded to aminopropyl silanized silica. A chiral recognition model for the separation of phthalide enantiomers has been …
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Design and synthesis of novel β-cyclodextrins and their application as chiral stationary phases for gas chromatography.
… separated only with use of systems containing a chiral selector. Cyclodextrins (CDs) and modified cyclodextrins have been used as chiral selectors for their ability to form host-guest complexes with various analytes. The scaffold of the CD allows for assembly of functional groups with controlled …
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Chromatographic Separation of Enantiomers of Some Physiologically Active Types of Compounds on Chiral Stationary Phases (Benzodiazepinones, Beta-Lactams, Beta-Aminoacids)
… have been separated by chromatography on chiral stationary phases. Thus benzodiazepinone enantiomers and enantiomers of aryl substituted (beta)-lactams can be separated directly on amino acid derived chiral stationary phases, whereas (beta)-amino acid enantiomers can be separated, after …
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New bio-analytical separations utilizing chiral mobile phase additives in thin layer chromatography and chiral stationary phases in high performance liquid chromatography
… important and rapidly developing field of study. Chiral separations of pharmaceutical compounds and important organic intermediates in high performance liquid chromatography (HPLC) and thin layer chromatography (TLC) were achieved. Two methods were employed for the direct liquid chromatographic …
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Enantioselective Adsorption of 1,3-Dithiolane-1-Oxides and Related Compounds on Liquid Chromatographic Amino Acid-Derived Chiral Stationary Phases (Resolution, Enantiomers, Sulfoxides)
Chiral stationary phases derived from N-3,5-dinitrobenzoyl amino acids such as (R)-phenylglycine, (S)-leucine, (S)-phenylalanine and (S)-valine bonded to aminopropyl silanized silica are employed for preparative and analytical liquid chromatographic separation of the enantiomers of …
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Extension of Chromatographically - Derived Molecular Recognition Concepts to Stereoselective Reactions and Transformations
Analogues of chiral stationary phases (CSPs) and analogues of enantiomeric analytes separable upon the CSPs were employed in the investigation of stereoselective reactions and transformations. N-(3,5-dinitrobenzoyl)phenylglycine and N-(3,5-dinitrobenzoyl)leucine were used to study the …
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Enantio-Selective Mechanism of the Poly-Proline Chiral Stationary Phase: a Molecular Dynamics Study
Poly-proline-based chiral stationary phases are relatively new stationary phases and have shown to be competitive to other commercially available chiral stationary phases for high performance liquid chromatography (HPLC). The conformational studies, solvation properties and enantio-selective …
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Mechanistic Aspects of Enantioselective Complexation
… of synthetic, brush-type liquid chromatographic chiral stationary phases (CSPs) has been investigated. The design and evaluation of a new family of $\pi$-basic CSPs which utilize these intercalative effects to enhance enantioselectivity is discussed. These CSPs, designed from mechanistic …
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Methods Development in Chiral Chromatography
Chiral stationary phases derived from N-3,5-dinitrobenzoyl amino acids, amides of 1-aryl-1-alkylamines and N-2-naphthyl amino acids have proven to be viable sorbents for the direct liquid chromatographic separation of enantiomers. In an effort to extend the utility of these chrial stationary …
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Investigations of molecular recognition processes
The use of chiral stationary phases (CSPs) for the separation of enantiomers is commonplace. A variety of $\alpha$-alkyl and $\alpha$-aryl substituted $\alpha$-amino phosphonates were prepared. The ability of several CSPs to separate the enantiomers of N-(3,5-dinitrobenzoyl) derivatives of …
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