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A porous behaviour of supramolecular nanosized calixarene based containers has been evidenced: they behave as adsorbents for the separation of small gases mixtures.

A series of new 2-hydroxy-3-methoxybenzylidenethiazolo[3,2-a]pyrimidines with different aryl substituents at the 5 position are synthesized and characterized by 1H/ 13C NMR and IR-spectroscopy and mass-spectrometry, as well as single crystal X-ray diffraction (SCXRD). It was demonstrated that the type of hydrogen bonding can play a key role in the chiral discrimination of these compounds in the crystalline phase. The hydrogen bond of the O–H...N type leads to 1D supramolecular heterochiral chains or conglomerate crystallization in the case of the formation of homochiral chains. The hydrogen bond of O–H...O type gave racemic dimers, which are packed into 2D supramolecular layers with a parallel or angular dimers arrangement. Halogen bonding of the N...Br or O...Br type brings a new motif into supramolecular self-assembly in the crystalline phase: the formation of 1D supramolecular homochiral chains instead 2D supramolecular layers. The study of cytotoxicity against various tumor cells in vitro was carried out. It was found that 2-hydroxy−3-methoxybenzylidenethiazolo[3,2-a]pyrimidines with 3-nitrophenyl substituent at C5 carbon atom demonstrated a high efficiency against M-HeLa (cervical adenocarcinoma) and low cytotoxicity against normal liver cells.

The interest in functional supramolecular systems for the design of innovative materials and technologies, able to fundamentally change the world, is growing at a high pace. The huge array of publications that appeared in recent years in the global literature calls for systematization of the structural trends inherent in the formation of these systems revealed at different molecular platforms and practically useful properties they exhibit. The attention is concentrated on the topics related to functional supramolecular systems that are actively explored in institutes and universities of Russia in the last 10–15 years, such as the chemistry of host–guest complexes, crystal engineering, self-assembly and self-organization in solutions and at interfaces, biomimetics and molecular machines and devices. The bibliography includes 1714 references.

A convenient procedure has been developed for the synthesis of 3β,28-diacetoxylup-20(29)-en-30-oic acid via oxidation of 3β,28-di-O-acetylbetulin with selenium dioxide in aqueous ethanol on heating, followed by oxidation of 3β,28-diacetoxylup-20(29)-en-30-al thus formed with sodium chlorite in tert-butyl alcohol. The alkylation of 3β,28-diacetoxylup-20(29)-en-30-oic acid with 1,3-dibrompropane and 1,5-dibromopentane in boiling acetonitrile in the presence of potassium carbonate afforded the corresponding ω-bromoalkyl esters in high yields.

3β,28-Diacetoxylup-20(29)-en-30-oic acid (obtained via oxidation of betulin diacetate) enters the addition reaction with P—H-phosphonium salts (triarylphosphonium trifluoroacetates) under mild conditions to afford β-carboxyalkylphosphonium salts. Structure and composition of the resulting compounds were confirmed by NMR and IR spectroscopy, mass spectrometry, and elemental analysis.

New di- and tetrasubstituted thiacalix[4]arenes in cone and 1,3-alternate configurations containing terpyridine and triazole fragments at the lower rim of the macrocycle, as well as model triazole-terpyridine, are synthesized. The structures and purity of the compounds are confirmed by NMR spectroscopy and high-resolution MALDI mass spectrometry. The compounds form luminescent complexes with lanthanide cations (europium and terbium) in a chloroform-methanol (10: 1) system during fluorimetric titration. The possibility of antenna ef ect during fluorescence sensitization in lanthanides by the thiacalixarene ligands is demonstrated. Successful immobilization of the terpyridine receptors on a solid substrate makes it possible to consider the Langmuir-Blodgett films on the basis of these receptors as promising adsorbents of lanthanide from nonaqueous media or organic salts and also provides new opportunities for the investigation of the luminescence characteristics of lanthanide complexes in thin films.

The work describes the synthesis of supramolecular and polymer nanocontainers based on carboxylate resorcinarene derivatives. A comparative analysis of their inclusive characteristics toward hydrophilic and hydrophobic substrates was carried out. The obtained containers and silver nanoparticles were used to develop composite materials, and their catalytic activity in the reduction of {tip}-nitrophenol was examined. It was shown that polymer nanocontainers are more ef cient in binding organic substrates, while the supramolecular containers are more suitable for the design of catalytically active composites. The reduction of {tip}-nitrophenol in the presence of nanocomposites based on supramolecular containers proceeds with a higher rate and does not show an induction period.

A water-soluble thiacalix[4]arene derivative containing four diethylenetriamine fragments in 1,3-alternate stereoisomeric form has been obtained for the first time. Using ethidium bromide, it has been found that the macrocycle can interact with calf thymus DNA. The macrocycle has been found to interact with DNA via groove binding. The presence of four diethylenetriamine fragments on the calixarene platform leads to multivalent interactions with DNA, resulting in an increase in the binding constant by two orders of magnitude compared to individual diethylenetriamine.

In this study, we report a synthesis of new nanocomposites, wherein TiO2 is introduced into multicharged polymeric matrix and covered with noble metals (Pt, Pd or Au) for the photocatalytic application. A photocatalytic activity investigation was performed by studying the degradation of methylene blue. It revealed that all obtained nanocomposites demonstrate enhanced photocatalytic ability when compared to pure TiO2, under both UV (24 °C) and solar light (−2 °C). The morphology and catalytic properties of the composites depend on the noble metals. The kinetic speed value of photodegradation was found to increase in the following sequence: TiO2 < TiO2-NPst ≈ Pd-TiO2@NPSt < Pt-TiO2@NPSt ≈ Au-TiO2@NPSt.

A procedure for the chloromethylation of lipophilic distally di-O-substituted calix[4]arene derivatives has been developed to prepare dichloromethyl derivatives of calix[4]arenes with long-chain alkyl fragments in cone configuration in high yields. From the chloromethylated derivatives, ammonium/imidazolium salts containing azidopropyl moieties have been synthesized in high yields. The structure of all obtained compounds has been established by 1D and 2D NMR, IR spectroscopy, and MALDI spectrometry. They can be further used as precursors of polytriazole/polyimidazole polymer species as promising carriers for metal-complex catalysis.

A new polymeric NHC carrier was synthesized by sequential supramolecular self-assembly and copper-catalyzed azide-alkyne cycloaddition (CuAAC) of amphiphilic imidazolium calix[4]arenes with octyl lipophilic fragments. Obtained polytriazole-imidazolium particles were found as monodisperse submicron particles, with the average diameter of 236 ± 34 nm and average molecular weight of 1380 ± 96 kDa. Successful CuAAC polymerization has been proved using IR spectroscopy and high-resolution ESI mass spectrometry. Polymeric particles, as well as aggregates made from precursor macrocycles, were decorated by Pd clusters (2 nm) for further catalytic investigations. Pd nanoclusters, supported on the polymeric surface, were found highly catalytically active in the model reduction of p-nitrophenol, giving reaction rates an order of magnitude higher compared to literature examples. The reaction was recycled using the same catalyst five times without any loss of activity.

The vibrational spectra of the p-tetrasulfonatothiacalix[4]arene pentasodium salt (TCAS) and tert-butylthiacalix[4]arene (BuTCA) were studied. Comparison of the TCAS and BuTCA IR spectra allows us to isolate the bands of tert-butyl and sulfonate groups. Geometry, IR and Raman spectra were calculated for conformation cone, partial cone, 1,2-, and 1,3-alternate. The most stable conformation of the TCAS is the cone. Characteristic bands were determined for each of the possible conformations. In the case of the TCAS molecule, four ions of sodium are coordinated with the oxygen atoms of sulfonate groups, and the fifth ion interacts with the oxygen and sulfur atoms of the macrocycle. Under the influence of sodium ions, the distribution of electron density in the TCAS molecule and its ability to supramolecular interactions change.

As a result of bright complexation properties, easy functionalization and the ability to self-organize in an aqueous solution, amphiphilic supramolecular macrocycles are being actively studied for their application in nanomedicine (drug delivery systems, therapeutic and theranostic agents, and others). In this regard, it is important to study their potential toxic effects. Here, the synthesis of amphiphilic calix[4]resorcinarene carboxybetaines and their esters and the study of a number of their microbiological properties are presented: cytotoxic effect on normal and tumor cells and effect on cellular and non-cellular components of blood (hemotoxicity, anti-platelet effect, and anticoagulant activity). Additionally, the interaction of macrocycles with bovine serum albumin as a model plasma protein is estimated by various methods (fluorescence spectroscopy, synchronous fluorescence spectroscopy, circular dichroic spectroscopy, and dynamic light scattering). The results demonstrate the low toxicity of the macrocycles, their anti-platelet effects at the level of acetylsalicylic acid, and weak anticoagulant activity. The study of BSA–macrocycle interactions demonstrates the dependence on macrocycle hydrophilic/hydrophobic group structure; in the case of carboxybetaines, the formation of complexes prevents self-aggregation of BSA molecules in solution. The present study demonstrates new data on potential drug delivery nanosystems based on amphiphilic calix[4]resorcinarenes for their cytotoxicity and effects on blood components.

A potential hypoxia-sensitive system host-guest complex of three calixarenes (including two with four anionic carboxyl and sulphonate azo fragments on the upper rim and a newly synthesized bis-azo adduct of calixarene in the cone configuration with azo fragments on the lower rim with the most widespread cationic and zwitterionic rhodamine dyes (123, 6G and B)) was studied using UV-VIS spectrometry and fluorescence as well as 1D and 2D NMR techniques. It was found that all three calixarenes form a complex with rhodamine dyes with a 1:1 composition. The association constants of calixarene-dye complexes with sulfonate calixarenes, especially in the case of tetra-anionic calixarene, turned out to be higher compared with carboxyl calixarene due to the more intense electrostatic interactions. For the first time using an HRESI MS technique, it was shown that the treatment of rhodamine 6G and 123 with sodium dithionite (SDT) produces a non-fluorescent leuco form of the dye, and only rhodamine B can be used with SDT without the occurrence of a side reduction. Moreover, it was identified that in addition to the reduction in the azo groups, SDT causes partial cleavage of the aryl ether bonds. The found features of SDT should be taken into account when SDT is used as an azoreductase mimic.

The effect of γ-radiation on the extraction properties of two functionalized calixarenes (p-tert-butyl-thiacalix[4]arene and p-tert-butylcalix[8]arene) is studied. The most characteristic products of the irradiated extractants interaction with diluent are identified by mass spectrometry. Extraction ability of studied calixarenes towards cesium and americium before and after irradiation is evaluated. Quantitative analysis of chloride and sulfate ions after irradiation is performed to estimate the radiological degradation degree of components. Irradiation has different effect on p-tert-butyl-thiacalix[4]arene and p-tert-butylcalix[8]arene extraction ability towards americium, which may be due to the nature and extraction ability of radiolysis products, and practically does not affect cesium extraction.

The vibrational spectra of p-sulfonatocalix [4] arene were studied. The geometrical parameters, the energies, the frequencies and the intensities of the bands in the IR and Raman spectra are calculated for four conformations. The most stable conformation of the p-sulfonatocalix[4]arene is the cone due to the cooperative cyclic intramolecular hydrogen bonding system. The strength of the hydrogen bonds depends on the type of substituent on the upper rim of the calixarene molecules. We studied the process of destruction of calixarenes using IR spectroscopy and TGA methods. Characteristic bands for each conformation were selected. HOMO covers aromatic units with notable conjugation, and LUMO belongs to sulfonate groups.

The attack of the thiol sulfur atom (P–SMe) on the methine carbon as the main route of the new reaction of dichloromethylarenes with S-methyl diethylthiophosphinate has been predicted and experimentally confirmed on the basis of the electronic structure of the S-alkyl esters of P(IV) acids. The processes of the mono- and di(dechloromethylthioylation) of dichloromethyl group have been realized. A new approach to the synthesis of the arenecarbaldehyde dimethyl dithioacetals has been developed avoiding the use of gaseous highly toxic methyl mercaptan.

Solvothermal synthesis involving tetrasubstituted carboxylic derivatives of [1.1.1.1]metacyclophane ( 1 – 2 ) bearing rigid phenyl spacer, that inherently adopt the 1 , 3 -Alternate conformation, with Manganese salts (acetate and nitrate) led to new 1D and 3D coordination polymers: { 1 3 -Mn 9 O 3 (CH 3 COO) 6 (C 5 H 5 N) 12 } ( 1 3 -Mn 9 ) and { 2 -Mn 2 (C 3 H 7 NO) 2 } ( 2 -Mn 2 ), respectively. The X-ray diffraction analysis revealed that: (i) ligand 1 , containing meta -benzoate coordinating sites, forms a 1D chiral helicoidal Coordination Polymer ( 1 3 -Mn 9 ) with trinuclear metallic clusters (Mn II Mn III 2 (μ 3 -O)) acting as linear connection nodes; (ii) ligand 2 , bearing para -benzoate moieties forms, a 3D diamond-like Coordination Polymer ( 2 -Mn 2 ) presenting Mn(II) polymeric chains bridged by tetrahedral-shaped ligand. The obtained Mn-based compounds are the first examples of coordination polymers based on tetrasubstituted [1.1.1.1]metacyclophane ligands bearing carboxylate coordinating groups.

A new strategy of synthesis of thiacalix[4]monothiacrown ethers in 1,3-alternate stereoisomeric form has been suggested and implemented through macrocyclization of the lower rim of 3-bromopropoxy-substituted thiacalixarenes by dithiols.

New p-tert-butyl thiacalix[4]arene derivative in the 1,3-alternate stereoisomeric form containing two diethylenetriamine groups and pentacosa-10,12-diynoic moieties on the opposide sides of macrocyclic cavity was synthesized using the copper(i)-catalyzed azide-alkyne cycloaddition. According to the dynamic and electrophoretic light scattering data, the synthesized macrocycle forms submicron particles with the sizes 200 nm and ζ-potential equal to 43 mV. The critical aggregation concentration of the macrocycle was 0.019 mmol L−1. The obtained macrocycle intercalates into calf thymus DNA (CT DNA) to form a lipoplex. Using ethidium bromide as a fluorescent probe intercalation of obtained macrocycle into CT DNA with following formation of a lipoplex with the ζ-potential equal to −30 mV was found. The macrocycle was used for the synthesis of mixed polydiacetylene particles with N-(2-aminoethyl)pentacosa-10,12-diynamide (PCDA) as a base lipid. The highest degree of polymerization is achieved in the system with the macrocycle to PCDA ratio equal to 1 : 4. Macrocycle embedding into the polydiacetylene particles significantly increases their colorimetric response to CT DNA. The response to CT DNA as a change in the color of a solution of particles from blue to red is seen by naked eye at the CT DNA concentration starting from 20 µmol L−1, which makes the obtained particles promising for bioanalytical application.

Amphiphilic calixarene derivatives with different lipophilicities and containing four 4,5-dicarboxytriazolyl fragments on the upper rim in a cone stereoisomeric form are obtained via azide-alkyne addition reaction. We showed that the amphiphilic macrocycles substituted with four octyl and tetradecyl groups on the lower rim form the monodisperse nanoaggregates in aqueous solutions. We found that the macrocycles possess fluorescence in the blue region. When concentration increases, there is a bathofloric shift of the emission maximum, which is due to aggregates. The resulting macrocycles were successfully used as a micellar medium for the Suzuki coupling reaction to show quantitative yields of iodine and bromoarenes in aqueous medium at room temperature.

Using the chemical reduction method, a copper-containing catalyst on an amino-modified silica was obtained. The structure and composition of the catalyst were characterized by low-temperature nitrogen adsorption and inductively coupled plasma mass spectrometry. It was found that the modification of silica with amino groups and copper nanoparticles leads to a significant change in textural characteristics: nanoparticles and the modifier fill the pores in the size range of 5-10 nm. Obtained catalyst showed good activity in the flow cycloaddition of azides and alkynes of various nature. The comparative activity of azides and alkynes was analyzed. It has been established that among the azides studied (benzyl azide, p-nitrobenzylazide, p-methoxybenzylazide, 2-azidoethylacetate and 1-azidodecane), alkyl and aryl azides with electron-withdrawing groups were most active due to an increase in the electrophilicity of the terminal nitrogen atom of the azide group. Among the studied acetylenes (phenylacetylene, hexin-1, trimethylsilylacetylene and propargyl alcohol), propargyl alcohol was the most and trimethylsilylacetylene was the less active. Increased activity of propargyl alcohol may be due to a donor hydroxyl group capable of coordinating with copper; reduced activity of trimethylsilylacetylene can be resulted from steric hindrances. p-tert-Butyl and p-H-calix[4]arens were also used in the reaction. Full conversion of macrocycles was achieved after 3 consecutive reaction cycles. The resulting triazoles were isolated and characterized by a complex of physical methods. Thus, It has been demonstrated that carrying out the reaction in a flow by maintaining stable and fully reproducible reaction parameters makes it possible to quickly evaluate the relative reactivity of molecules.

A copper-palladium catalyst supported on amino-modified silica has been synthesized by chemical reduction. It has been found that submicron particles of a copper-palladium alloy are formed on the silica surface. Unlike commercially available palladium catalysts (Pd/Al2O3, Pd/C, Pd/BaSO4), the synthesized copper-palladium catalyst makes it possible to selectively reduce the nitro group in 3-nitrobenzaldehyde and 1-chloro-4-nitrobenzene.