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Amphiphilic calix[4]resorcinarenes are a class of macrocyclic compounds with broad potential utility including nanomedicine. Here the synthesis of new carboxybetaine and carboxybetaine ester calix[4]resorcinarene bearing 4-(dodecyloxy)phenyl groups on the lower rim is presented. The compounds were characterized by 1H-NMR, 13C-NMR, 2D NMR, IR, ESI and elemental analysis. The critical association concentration values are 1.00 × 10−5 and 1.18 × 10−5 mol·L−1 for carboxybetain and ester, respectively. The hemolytic activity of the macrocycles and their cytotoxicity against normal (WI-38, Chang liver) and tumor cells (M-HeLa) are also estimated. [ABSTRACT FROM AUTHOR]

Here we present the consecutive study of colloid systems formed by novel isatin derivative as compound with high pharmacological potential and series of carboxyresorcinarenes. The azo-modified isatin derivative bearing ammonium moiety ( I-3 ) was synthesized and its antimicrobial activity was investigated. To increase its solubility the solubilization experiment using amphiphilic carboxyresorcinarenes, characterized by low hemolytic activity, was carried out. The I-3 – macrocycles systems were studied by NMR, UV–vis, DLS and TEM. The FT PGSE and 2D NOESY NMR methods demonstrated, that solubilization of I-3 is caused by the incorporation of its molecules in the hydrophobic part of the macrocycles associates. Herewith the loading efficiency of I-3 into the macrocycles associates was reached of 20–30% due to the change of the volume of hydrophobic part of associates by varying the length and structure of hydrophobic substituents of macrocyclic amphiphiles. [ABSTRACT FROM AUTHOR]

ABSTRACT New phosphorylated aminoacetal has been synthesized by the Kabachnik-Fields reaction; its reactivity has been studied in acid-catalyzed condensation with linear polyphenols (2-methylresorcinol, resorcinol, pyrogallol) and the Mannich reaction with macrocyclic polyphenol (calix[4]resorcinol). It has been determined for the first time that acid-catalyzed reaction of phosphorus-containing acetal with resorcinol and its derivatives in ethanol in the presence of hydrochloric acid gives new phosphorylated piperazines in addition to the compounds of diarylmethane series. Condensation of macrocyclic polyphenol (calix[4]resorcinol) with formaldehyde and N-((dihexylphosphoryl)methyl)-2, 2-dimethoxyethylamine (the Mannich reaction) has resulted in novel tetrasubstituted calixarene containing aminophosphine oxide and acetal groups on the 'upper rim' of molecule. [ABSTRACT FROM AUTHOR]

Abstract: The IR, 1H and 13C NMR data, as well as conformation and dynamic behaviour of tetrathiacalix[4]arenes functionalized by hydrazone fragments are reported. The influence of isomers of thiacalix[4]arenes, the removal of tert-butyl groups from upper rim of macrocycle and the replacement of a phenyl substituents in the hydrazone fragments by 2-pyridyl ones on conformational properties of the compounds are discussed. The structural peculiarities of the cone isomer of 25,26,27,28-tetrakis[N2-(2-pyridinylmethylidene)hydrazinocarbonylmethyloxy]-2,8,14,20-tetrathiacalix[4]arene and the 1,3-alternate isomer of 25,26,27,28-tetrakis[N2-(benzylidene)hydrazinocarbonylmethyloxy]-2,8,14,20-tetrathiacalix[4]arene in solution are compared with their crystal structures obtained by X-ray analysis. The correlation between extraction efficiency data obtained for these compounds earlier and the conformational features of calix[4]arene hydrazone derivatives studied in this work was performed. [Copyright &y& Elsevier]

The octacarboxylic derivative of tetrapentylcalix[4]resorcinarene ( 1 ) was used as stabilizer for preparation of silver nanoparticles (AgNPs) hydrosol. The calixresorcinarene-capped nanoparticles Ag@ 1 are stably dispersed in an aqueous colloid solution and have an average diameter of 4–6 nm (TEM). The interaction of the macrocycle 1 , possessed the receptor properties, with the cationic surfactant cetyltrimetylammonium bromide (CTAB) leads to the hydrophobization of AgNPs hydrosol. It was shown, that macrocycle 1 in its individual solution forms the hydrophobic associate with 8 mol of CTAB ( 1 H NMR, 2D NOESY). Various and complicated influence of CTAB/macrocycle molar ratio on the hydrophobization of AgNPs and their transfer into organic phase was demonstrated. The initial Ag@ 1 and modified Ag@ 1 -CTAB were characterized by UV-vis and FTIR spectroscopy, DLS, and TG/DSC methods It was shown that the efficiency of water/organic phase transfer depends on the macrocycle/surfactant molar ratio. The presented supramolecular approach can be useful to form the ordered nanostructures through supramolecular modification and self-organization of hybrid metal nanoparticles. [ABSTRACT FROM AUTHOR]

The synthesis of small (2–3 nm) silver nanoparticles in the presence of new amidoaminocarboxylic tetrapentylcalix[4]resorcinarene and the binding of the antitumor drug Doxorubicin by a macrocycle in solution and on the surface of nanoparticles are described. [ABSTRACT FROM AUTHOR]

Abstract: A new strategy for the synthesis of bifunctional compounds, based on 1,3-alternate tetrathiacalix[4]arene precursors functionalized by pairs of carboxylic acid and ester groups located on opposite sides of the macrocycle platform is described. These building blocks were prepared by the Cs2CO3 induced selective hydrolysis of tetrathiacalix[4]arene tetraester derivatives. A mechanism for the selective hydrolysis is suggested. The structures of the compounds are elucidated by NMR spectroscopic analysis and X-ray single crystal diffraction. [Copyright &y& Elsevier]

Reaction of calix[4]resorcinols, containing acetal moieties on the upper rim, with resorcinols leads to calixarenes bearing four diarylmethane fragments on the upper rim of the molecule. [ABSTRACT FROM AUTHOR]