Abstract

VARGAS-MARTINEZ, María Gabriela  and  RAMIREZ-GALICIA, Guillermo. Molecular Modeling and Chiral Separation of Benzodiazepines by Capillary Electrophoresis Using Highly Sulfated Cyclodextrins. J. Mex. Chem. Soc [online]. 2018, vol.62, n.2, pp.358-370. ISSN 1870-249X.  https://doi.org/10.29356/jmcs.v62i2.413.

A capillary electrophoretic method for the chiral separation of the 3-chiral-1,4-benzodiazepines was developed. Enantiomeric resolution of oxazepam, lorazepam, temazepam, and lormetazepam was achieved using sulfated cyclodextrins (CD's) as chiral selectors. A 3-levels, 4-factors fractional factorial (34-2) design was applied to test 3 different CD's: heptakis-6-sulfato-β-cyclodextrin (HSβCD), heptakis-(2,3-diacetyl-6-sulfato)-β-cyclodextrin (HDASβCD), and heptakis-(2,3-dimethyl-6-sulfato)-β-cyclodextrin (HDMSβCD). The CD type, its concentration, the pH of the electrolyte, and % organic modifier were tested as the factors in the experimental design. The highest resolution values were obtained using a 20 mM borate buffer, pH 9.0 with the addition of 5 % HSβCD and 15 % methanol as an organic modifier. At these separation conditions, the equilibrium constants of the benzodiazepine-HSβCD complex formation were calculated. A theoretical study of the interaction benzodiazepine-HSβCD complex using semiempirical calculations is postulated.

Keywords : Chiral Separation; Benzodiazepines; Sulfated Cyclodextrins; Molecular Modeling.

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