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

Selectivity of Calixarene-bonded Silica-phases in HPLC: Description of Special Characteristics with a Multiple Term Linear Equation at Two Different pH-Values

“…Additionally to the well known interactions of alkyl-bonded silicas, they can give rise to retention by forming complexes [2][3][4][5][6][7][8][9][10] and by providing p-p-interactions 3,7,11,12 or p-electron-transfer. [7][8][9][10][11][12] For that reason, calixarene-bonded phases exhibit special selectivities.…”

“…[7][8][9][10][11][12] For that reason, calixarene-bonded phases exhibit special selectivities. It is obvious that differences of selectivities can be distinct between different kinds of calixarene-bonded phases and especially between calixarene-bonded phases and common C18-phases.…”

Preparation and Characterization of Bonded-Phases of Calixarene-Sulfonyl-Carboxamides in Partial-Cone Conformation for Determination of Salbutamol in Livestock by Nano-Mediated Bonded-Phases: Nano-Baskets of Calixarene in Partial-Cone Conformation

“…The resulting solution was filtered through 0.22 μm filter and the filtrate (10 μL) was ready for analysis. p-tert-butyl-calix [8]arene steroids [25] calix [6]arene-p-sulfonate nitrophenol, methoxyphenol, cresol, aminophenol and chlorophenol [26] C-tetraundecylcalix [4]resorcinarene cytosine, uracil and thymine [27] calix [8]arene tricyclic neuroleptic [28] calix [4]arenes benzene or uracil derivatives [29] caltrex BIIE paracetamol, caffeine and acetylsalicylic acid [30] caltrex AIII celecoxib [31] fluorinated calix [4]arene fluorine compounds [32] p-tert-butyl-calix [8]arene aromatic carboxylic acids [33] 9-amino(9-deoxy)-epiquinine calix [4]arene, 9-amino(9-deoxy)-quinine calix [4]arene cyclic amino acids [34] caltrex AI, caltrex AII, caltrex AIII, caltrex BI, caltrex BII and caltrex BIII PAHs, phenols, substituted aromatics, xanthines, barbituric acid, benzoic acid esters [35] calix [4]arene tetradiethylamide amino acid ester hydrochlorides [36,37] calix [4]resorcinarene and calix [4,6,8]arene flupentixol, chlorprothixene, clopenthixol, and doxepin [38] p-tert-butylcalix [4,6,8]arene disubstituted aromatics, uracil derivatives, and estradiol epimers [39] p-tert-butylcalix [4,6,8]arene peptide bond isomers of proline [40] p-tert-butyl-calix [4]arene nucleosides, PAHs and bases [41] calix [6]<...>…”

Preparation and Characterization of a New p-tert-Butyl-calix[8]arene-bonded Stationary Phase for High-Performance Liquid Chromatography

“…The reported methods mainly include hydrosilation addition, thiolene addition and the condensation reaction of the coupling reagents. [9][10][11][12] The addition reaction of p-allycalixarenes with triethoxysilane under catalysis with hexachloroplatinic acid was a usual method to prepare the calixarene-bonded phases. 10 In this work, a new approach proposed for CABS included two steps: the precursor, 3-glycidoxypropyl-bonded stationary phase (GBS), was first synthesized; then, the calix [8]arene bonded phase was prepared by using the phenolic sodium of calix [8]arene in the presence of a phase-transfer catalyst, such as quaternary ammonium salt, to cleave the epoxy group of GBS.…”

“…7 In 1993, Glennon and coworkers [8][9][10] prepared silica-bonded calix [4]arene tetraester and silica-bonded calix [4]arene tetradiethylamide stationary phases to separate metal ions and amino acid esters for the first time. Gebauer et al [11][12][13] successfully separated disubstituted aromatics, nucleosides, uracil derivatives, estradiol epimers and cis/trans isomers of proline-containing peptides on calix[n]arene-bonded (n = 4, 5, 6, 8) silica gel. Menyes et al 14 reported that a hexapropylether of p-tert-butyl-calix [6]arene was covalently linked to silica for the separation of PAHs and fullerenes, and showed higher selectivity and lower consumption of the solvent than conventional RP-C18.…”