Publications by authors named "Daniel Wayne Armstrong"

The gas chromatographic separation of enantiomers of 2-Br carboxylic acid derivatives was studied on four different 6-TBDMS-2,3-di-O-alkyl- β- and -γ-CD stationary phases. The differences in thermodynamic data {ΔH and -ΔS} for the 15 structurally related racemates were evaluated. The influence of structure differences in the alkyl substituents covalently attached to the stereogenic carbon atom, as well as in the ester group of the homologous analytes, and the selectivity of modified β- and γ- cyclodextrin derivatives was studied in detail.

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Sulfated cyclofructan 6 (S-CF6) and sulfated cyclodextrins (S-α-, β-, γ-CDs) are highly selective chiral selectors for the enantioseparation of basic solutes. In this study, S-CF6 was introduced for the enantiomeric separation of four basic pharmaceuticals (including tamsulosin, tiropramide, bupivacaine, and norephedrine) by capillary electrophoresis (CE), and the enantiomeric separation performance was compared with S-α-, β-, γ-CDs. The effects of the chiral selector type, chiral selector concentration, operating voltage, and column temperature were examined and optimized.

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