High Performance Liquid Chromatography on Calixarene-Bonded Silica Gels. II. Separations of Regio-and Stereoisomers on p-tert-Butylcalix[n]arene Phases

Abstract

The chromatographic behavior of new calix[n]arene-bonded (n = 4, 6, 8) silica gels are described. Cavities of different size and shape are formed depending on the number of aromatic moieties. The differences in ring size are utilized to investigate chromatographic selectivities towards analytes of various substance classes, including disubstituted aromatics, uracil derivatives, and estradiol epimers. Our results indicate that these calixarene-bonded phases show a high resolution power for regio- and stereoisomers.