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ph Dependent Enantioselection of Amino Acids by Phosphorous-Containing Calix[4]resorcinarene in Langmuir Monolayers

Pietraszkiewicz M., Prus P., Bilewicz R.

Polish Journal of Chemistry

1999

Vol. 73, nr 12

2035-2042

Lipophilic calix[4]resorcinarene with phosphorous acid amide groups linking oxygen atoms is a rigid system of the cavitand type, in which conformational flexibility is strongly limited. These chiral receptors form stable Langmuir monolayers on water surface with surface area per molecule in the compressed layer being almost ph-independent.

pH Dependent Enantiomeric Recognition of Amino Acids by Mannich-Type Calix[4]resorcinarenes in Langmuir Monolayers

Pietraszkiewicz M., Prus P., Bilewicz R.

Polish Journal of Chemistry

1999

Vol. 73, nr 11

1845-1853

The surface potential of these compounds is distinctly higher in the presence of substituents and its further increase upon decreasing the pH of the subphase is observed only for the derivatized calixarenes. This means that protonation on the amine centers is the factor determining the properties of the monolayer.

Transport studies of inorganic and organic cations across liquid membranes containing Mannich-base calix[4]resorcinarenes

Pietraszkiewicz O., Kozbiał M., Pietraszkiewicz M.

Polish Journal of Chemistry

1998

Vol. 72, nr 5

886-892

Three calix[4]resorcinarenes, two of them incorporating Mannich-type amino functions (C2 and C3), have been studied in respect to their ionoselectivities towards inorganic alkali cations as well as for organic primary ammonium cations, by ion transport across the bulk liquid membrane and extraction experiments. The ligand C3 displayed particular ionoselectivity for lithium ion, as a carrier in toluene membrane. The discrimination of organic primary ammonium ions was remarkable in liquid membranes, and the pattern of this discrimination depended on the membrane composition. Selectivities for both inorganic and organic ions depended significantly on the membane composition, the substituent in the calix[4]resorcinarene, and the counterion present in the salts studied.

Calix[4]resorcinarenes as dynamic coatings for modified stationary RP-18 phase for HPLC

Pietraszkiewicz M., Pietraszkiewicz O., Koźbiał M.

Polish Journal of Chemistry

1998

Vol. 72, nr 8

1963-1970

Lipophilic calix[4]resorcinarenes, derived from lauryl aldehyde and resorcinol, are strongly adsorbed on the modified silica gel RP-18 during HPLC. This technique leads to a column with an excellent time stability and good reproducibility of the retention characteristics of substituted phenols as analytes.