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Decasubstituted pillar[5]arenes containing 2‐ and 4‐thiopyridine and thiophenol fragments were synthesized for the first time. The spatial structure of pillar[5]arene containing 4‐thiopyridine fragments was established by X‐ray crystallography. Unique fluorescent self‐assembling metallo‐supramolecular structures with Cu(I) cations were synthesized based on the macrocycle. It was found that the obtained metallo‐supramolecular structures are able to bind CO2, which was confirmed by a number of methods. The effect of CO2 molecules on pillar[5]arene/Cu(I) complexation was also tested using an electrochemical device, and the selectivity of electron exchange and the reversibility of changes in voltammograms were shown, which makes it possible to use the synthesized complex for selective monitoring of CO2 in gaseous media and in the development of new photosynthetic systems. [ABSTRACT FROM AUTHOR]

The formation of supramolecular associates based on water-soluble p-tert-butylthiacalix[4]arenes with has been studied. It was shown that amphiphilic p-tert-butylthiacalix[4]arenes preferably formed supramolecular associates with aromatic α-amino acids (tyrosine and tryptophan). Increasing size of the substituents of p-tert-butylthiacalix[4]arenes led to increase molecular weight of supramolecular associates based on the macrocycles and 'guest' molecules. The spatial structures of p-tert-butylthiacalix[4]arenes and their associates with phenylalanine were studied by two-dimensional 1H-1H nuclear Overhauser effect NMR spectroscopy. The ability of aggregates based on p-tert-butylthiacalix[4]arenes and to effectively interact with bovine serum albumin with the formation of 7- to 8-nm nanoparticles was shown. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Robust mesoporous membranes composed of silica spheres were surface-modified with chiral selector moieties, including small molecules, macrocycles, and polymers. Diffusion rates of enantiomers of a chiral dye through the resulting asymmetrically modified colloidal membranes were measured and the corresponding permselectivities were calculated. The membranes showed enantioselectivities in the range of 1.2-1.8, which were not significantly affected by the structure of the surface-immobilized chiral electors. This selectivity is on par with most reported polymer-based solid membranes and bulk liquid membranes. The enantioselectivity results from the surface-facilitated mechanism of transport of enantiomers through the mesopores. [ABSTRACT FROM AUTHOR]

A novel potentiometric sensor based on screen-printed carbon electrode covered with electropolymerized polyaniline (PANI) and unsubstituted pillar[5]arene as ionophore has been developed and tested in potentiometric measurements of pH and metal ions. The introduction of pillar[5]arene improved the reversibility of the pH response in the range from 2.0 to 9.0 with the slope of 45 mV/pH. Among metal cations, the response to Fe3+ and Ag+ ions was referred to PANI redox conversion whereas the signal toward Cu2+ in the range from 1.0×10−6 to 1.0×10−2 M (limit of detection ( LOD) 3.0×10−7 M) to specific interaction with the macrocycle. [ABSTRACT FROM AUTHOR]

Robust mesoporous membranes composed of silica spheres were surface-modified with chiral selector moieties, including small molecules, macrocycles, and polymers. Diffusion rates of enantiomers of a chiral dye through the resulting asymmetrically modified colloidal membranes were measured and the corresponding permselectivities were calculated. The membranes showed enantioselectivities in the range of 1.2-1.8, which were not significantly affected by the structure of the surface-immobilized chiral electors. This selectivity is on par with most reported polymer-based solid membranes and bulk liquid membranes. The enantioselectivity results from the surface-facilitated mechanism of transport of enantiomers through the mesopores. [ABSTRACT FROM AUTHOR]

Promising membrane transport and separation systems for selected dicarboxylic, α-hydroxy- and α-amino acids based on thiacalixarene platform have been developed. For the first time, p-tert-butyl thiacalix[4]arenes functionalized at the lower rim with aminophosphonate fragments have been obtained and characterized. As was established by UV-vis spectroscopy, membrane extraction and HPLC, the substitution of amino groups by α-aminophosphonate units significantly enhances the selectivity of host molecules that bind to aspartic and glycolic acids. The aminophosphonate compounds synthesized can be used in the development of sensors and systems employed in the purification and separation of organic acids. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The shape of supramolecular aggregates based on stereoisomers of p-tert-butyl thiacalix[4]arenes functionaiized with secondary, tertiary amide and hydrazide groups at the lower rim in cone, partial cone and 1,3-alternate conformations with several metal cations were investigated by atomic force microscopy. The examined p-tert-butyl thiacalix[4]arenes form host-guest complexes; dimers, spherics ellipsoids and elongated nanoscale particles depending on the conformation of macrocycles, the nature of the binding centers and the nature of the metal cation. Only associates formed by p-tert-butyl thiacalix[4]arenes with morpholide groups at the lower rim in cone conformation with silver cations exhibited a higher antimicrobial activity. [ABSTRACT FROM AUTHOR]

In this work, we present a new type of amphiphilic membrane-anchoring agents that can be easily obtained by the between terpene myrcene and N-substituted maleimides. The interaction between the compounds and small unilamellar dipalmitoylphosphatidylcholine vesicles was investigated using , microgravimetry, and turbidimetry. The ability of the compounds to embed in the phospholipid membrane was shown to be strongly dependent on the charge of their polar group. The insertion of the compounds studied into the lipid bilayer did not lead to disruption of the dipalmitoylphosphatidylcholine vesicles up to the highest tested drug to lipid molar ratio of 0.5 to 0.6. Low lipid solubilization ability of the compounds as well as their rigid nonplanar structure makes them an interesting alternative to the common membrane-anchoring structural motifs. [ABSTRACT FROM AUTHOR]

The article presents information on the synthesis, preparative methods and chemical structure of guanidine-equipped thiacalix[4]arenes.