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Shape-persistent macrocycles enable superior control on molecular self-assembly, allowing the preparation of well-defined nanostructures with new functions. Here, we report on anionic amphiphilic calixarenes of conic shape and their self-assembly behavior in aqueous media for application in intracellular delivery of peptides. Newly synthesized calixarenes bearing four phosphonate groups and two or four long alkyl chains were found to form micelles of ∼ 10 nm diameter, in contrast to an analogue with short alkyl chains. These amphiphilic calixarenes are able to complex model (oligo-lysine) and biologically relevant (HIV-1 nucleocapsid peptide) cationic peptides into small nanoparticles (20-40 nm). By contrast, a control anionic calixarene with short alkyl chains fails to form small nanoparticles with peptides, highlighting the importance of micellar assembly of amphiphilic calixarenes for peptide complexation. Cellular studies reveal that anionic amphiphilic calixarenes exhibit low cytotoxicity and enable internalization of fluorescently labelled peptides into live cells. These findings suggest anionic amphiphilic macrocycles as promising building blocks for the preparation of peptide delivery vehicles.

A preparative method for the synthesis of optically pure N-(1-phenylethyl)amides of inherently chiral (cR)- and (cS)-dibenzoyloxy-calix[4]arene acetic acids has been developed. Their absolute stereochemical configuration was determined by X-ray diffraction analysis.

Zn ions are significant for maintaining the proper human organism functioning, thus monitoring­ the zinc content in living cells and the development of sensitive tracking systems and sensors for Zn is particularly important. The purpose of the work was to study the properties of synthetic thiacalix[4]arene C-800 (5,11,17,23-tetrakis[(hydroxy-ethoxyphosphonyl)methyl])-25,26,27,28-tetrahydroxythiacalix[4]arene) as a fluo­rescent sensor for zinc ions in living cells. Our studies demonstrated that thiacalix[4]arene C-800 containing­ four hydroxy-ethoxyphosphonylmethyl groups on the upper rim exhibited fluorescent properties at 340 nm excitation wavelength. Fluorescence intensity of thiacalix[4]arene C-800 was increased significantly in the presence of Zn cations, while cations of other metals, such as Mg2+, Ca2+, Cd2+, and Pb2+ did not affect it. Computer modeling demonstrated that two Zn cations interact with the oxygen atoms of four hydroxy-ethoxyphosphonylmethyl groups. It was shown that thiacalix[4]arene C-800 quickly penetrated rat myometrial cells that led to an increased intracellular fluorescence level. The addition of Zn2+ to cells, stained with thiacalix[4]arene C-800, was followed an even greater increase of intracellular fluorescent signal intensity. No effect of thiacalix[4]arene C-800 on reactive oxygen species production in myometrial cells was detected as well as on cells viability in the range of its 50-250 μM concentrations. Thus, thiacalix[4]arene C-800 can potentially be used as a selective fluorescent probe for the detection of Zn2+ in living cells.

Two new derivatives of calix[4]arene bearing on the upper rim 2-thiopenyl (Thicalix) or 2-pyridyl (Pycalix) Schiff-base substituents have been synthesised and characterised by IR, NMR, MS, and sing...

bis-Methoxycarbonylmethoxy derivatives capable of reacting with the surface of aminopropylated silica gel with the formation of chemically and thermally stable amide bonds were obtained by regioselective distal dialkylation of hydroxyl groups of phosphorylated tetrahydroxycalix[4]arenes in high yields. It was found that phosphine oxide and phosphonate P=O groups localized on the upper rim cooperatively bind Eu3+ cations and effectively sorb them from nitric acid solutions.

The discovery of compounds that might modify myometrial contractility is an important area of researches. In our previous experiments, we found that some representatives of macrocyclic compounds fami­ly – calix[4]arenes – can modify the enzymatic and transport activity of membrane-bound cation-transport ATP hydrolases. The aim of this work was to study and compare the effect of calix[4]arene C-107 on the enzymatic activities of Mg2+-dependent ATPases of the uterine smooth muscle, namely: ouabain-sensitive Na+,K+-ATPase, plasma membrane Ca2+-independent “basal” Mg2+-ATPase, ATPase of the actomyosin complex and myosin subfragment-1, with effect on the contractile activity of the myometrium. It was shown that calix[4]arene C-107 efficiently inhibited myometrium Na+,K+-ATPase (I50 = 54 ± 6 nM) selectively to other ATP-hydrolases of the plasma membrane and simultaneously activated the enzymatic activity of the myosin ATPase of smooth muscles (A50 = 9.6 ± 0.7 μM). Such reciprocal biochemical effects led to the stimulation of the smooth muscle contractile activity that was demonstrated by the tensometric method using different isolated smooth muscles. Calix[4]arene С-107 was shown to stimulate the increase of the tonic component of myometrium contractions induced by oxytocin, as well as contractions of the caecum muscles induced by high-potassium solution or acetylcholine, and to maintain increased tension for a long time. Thus, calix[4]arene C-107 is a prospective compound for enhancing the smooth muscle basal tone and/or contraction in case of hypotonic dysfunctions.

The formation of calixarene-based liposomes was investigated, and the characterization of these nanostructures was carried out using several techniques. Four amphiphilic calixarenes were used. The length of the hydrophobic chains attached to the lower rim as well as the nature of the polar group present in the upper rim of the calixarenes were varied. The lipid bilayer was formed with one calixarene and with the phospholipid 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine, DOPE. The cytotoxicity of the liposomes for various cell lines was also studied. From the results obtained, the liposomes formed with the least cytotoxic calixarene, (TEAC12)4, were used as nanocarriers of both nucleic acids and the antineoplastic drug doxorubicin, DOX. Results showed that (TEAC12)4/DOPE/p-EGFP-C1 lipoplexes, of a given composition, can transfect the genetic material, although the transfection efficiency substantially increases in the presence of an additional amount of DOPE as coadjuvant. On the other hand, the (TEAC12)4/DOPE liposomes present a high doxorubicin encapsulation efficiency, and a slow controlled release, which could diminish the side effects of the drug., This work was financed by the Consejería de Conocimiento, Innovación y Universidades de la Junta de Andalucía (FQM-206, FQM-274, and PY20-01234), the VI Plan Propio Universidad de Sevilla (PP2019/00000748), RTI2018-100692-B-100; P18-RT-1271; PI18-0005-2018; VI-PP AY.SUPLEM- 2019; RYC-2015-18670, The R+D+I grant PID2019-104195G from the Spanish Ministry of Science and Innovation-Agencia Estatal de Investigación/10.13039/501100011033 (P.H.) and the European Union (Feder Funds). The authors thank the University of Seville for the grant VPPI-US. J.A.L. also thanks the Fundación ONCE funded by the Fondo Social Europeo.

Host - Guest complexation of 5,17- bis- ( N - tolyliminomethyl )-25,27- dipropoxycalix [4] arene with aliphatic di carboxylic acids C4 – C10 has been studied in water-organic solution by the RP HPLC and molecular modeling methods. T he stability constants (log K A = 2.56 – 3.05) of the supramolecular complexes are depended on structure, pKa and log P values of the acids . The complexation is determined by the hydrogen bonds of the COOH group of the dicarboxylic acids with nitrogen atoms at the upper rim or oxygen atoms at the lower rim of the calixarene.

The self-aggregation of four amphiphilic cationic calix[4]arenes, CALIX, in aqueous solutions was investigated in this work. The nature of the polar group present at the upper rim as well as the length of the hydrophobic tails attached to the lower rim was varied. All the calixarenes present two critical aggregation concentrations, CAC1 and CAC2. For [CALIX] < CAC1 only micelles are present, within the range CAC1 < [CALIX] < CAC2 micelles as well as vesicles are observed, and for [CALIX] > CAC2 micelles and a wide distribution of vesicles were found. Cell viability experiments show that calixarene micelles and several of the calixarene vesicles investigated could be used as biocompatible nanocarriers. On this basis, the study of the interactions between the cationic calixarene aggregates (micelles and vesicles) and calf thymus DNA, ctDNA, were done and the results indicated that most of them strongly interact with the polynucleotide, inverting its charge. Micelles totally compact the ctDNA, while vesicles only partially cause conformational changes in the nucleic acid. Therefore, the CALIX micelles show potential as vectors in gene therapy. The encapsulation of the antineoplastic drug doxorubicin into the calixarene aggregates was also investigated. A high encapsulation efficiency was found for micelles and, specially, for vesicles. However, DOX-loaded calixarene vesicles present low stability at 37 °C, which is a serious restriction in their use as nanocarriers for this drug. The release of DOX from the calixarene micelles shows that they could lengthen the half-life of free doxorubicin in the body and, as a result, lower amounts of drug could be used in the cancer treatments diminishing the important side effects of DOX., This work was supported by the Consejería de Educación y Ciencia de la Junta de Andalucía (P12-FQM-1105, FQM-206 and FQM-274, and PI-0005-2018), the VI Plan Propio Universidad de Sevilla (PP2018-10338), the Ministerio de Ciencia, Innovación y Universidades (RTI2018-100692-B-I00), the grant Ramon y Cajal RYC2015-1867 and the European Union (Feder Funds). The authors thank the University of Seville for the grant VPPI-US.

International audience; The nucleocapsid protein (NC) is a highly conserved protein that plays key roles in HIV-1 replication through its nucleic acid chaperone properties mediated by its two zinc fingers and basic residues. NC is a promising target for antiviral therapy, particularly to control viral strains resistant to currently available drugs. Since calixarenes with antiviral properties have been described, we explored the ability of calixarene hydroxymethylphosphonic or sulfonic acids to inhibit NC chaperone properties and exhibit antiviral activity. By using fluorescence-based assays, we selected four calixarenes inhibiting NC chaperone activity with submicromolar IC50 values. These compounds were further shown by mass spectrometry, isothermal titration calorimetry, and fluorescence anisotropy to bind NC with no zinc ejection and to compete with nucleic acids for the binding to NC. Molecular dynamic simulations further indicated that these compounds interact via their phosphonate or sulfonate groups with the basic surface of NC but not with the hydrophobic plateau at the top of the folded fingers. Cellular studies showed that the most soluble compound CIP201 inhibited the infectivity of wild-type and drug-resistant HIV-1 strains at low micromolar concentrations, primarily targeting the early steps of HIV-1 replication. Moreover, CIP201 was also found to inhibit the flipping and polymerization activity of reverse transcriptase. Calixarenes thus form a class of noncovalent NC inhibitors, endowed with a new binding mode and multitarget antiviral activity.

Using enzymatic assays and kinetic analysis, we demonstrated that 100 µM calix[4]arene C-956 (5,11,17,23-tetra(trifluoro)methyl-(phenylsulfonylimino) methylamino-25,27-dioctyloxy-26,28-dipropoxycalix[4]arene) had the most significant inhibitory effect on the plasma membrane Са2+,Mg2+-АТРase activity compared to effects of other calix[4]arenes, and had no effect on specific activities of other membrane ATPases. Using confocal microscopy and fluorescent probe fluo-4, we observed an increase of the intracellular level of Ca2+ after application of calix[4]arene C-956 to immobilized myocytes. Analysis of the effect of calix[4]arene C-956 on the hydrodynamic diameter of myocytes demonstrated that application of calix[4]arene C-956 solution decreased this parameter by 45.5 ± 9.4% compared to control value similarly to the action of uterotonic drug oxytocin.

Мета роботи. Порівняння похідних сульфонілкалікс[4]арену, які містять здатні та нездатні до іонізації залишки на верхньому вінці макроциклу, як інгібіторів РТР1В та інших протеїнотирозинфосфатаз. Результати та їх обговорення. Властивості сульфонілкалікс[4]арену з чотирма фосфонатними групами, приєднаними до верхнього вінця макроциклу, порівнювалися з властивостями сполук, які містять чотири трет-бутильні або трифторацетамідні замісники. Було встановлено, що сульфонілкалікс[4]арентетракіс-метилфосфонова кислота інгібує PTP1B зі значенням IC50 в низькомікромолярному діапазоні без селективності стосовно інших PTPаз, таких як TC-PTP, MEG1, MEG2, SHP2 та PTPβ. Модифікація сульфонілкалікс[4]арену залишками трифторацетаміду забезпечила інгібування PTP1B зі значенням IC50 1,4 мкМ з 4-28-кратною селективністю відносно інших PTPаз. Для з’ясування інгібувальної здатності похідної сульфонілкалікс[4]арену з трифторацетамідними замісниками відносно PTP1B було застосовано молекулярний докінг та моделювання методом молекулярної динаміки. Обговорюється можливий механізм інгібування. Експериментальна частина. Активність сполук досліджували спектрофотометрично, вимірюючи швидкість ферментативного гідролізу п-нітрофенілфосфату як субстрату протеїнотирозинфосфатаз. Молекулярний докінг було виконано за допомогою AutoDock Vina. Висновки. Це дослідження може бути основою нового підходу до розробки інгібіторів PTPаз шляхом модифікації верхнього вінця сульфонілкалікс[4]аренового каркасу неіоногенними замісниками.

The results of the author studies of functional calixarene nanostructures are summarized. Calixarenes modified by various functional groups were created with receptor properties relative to cations, anions, gases, organic molecules and biomolecules. Calixarene nanostructures have been used to develop extraction and adsorption agents for radionuclides, sensitive elements of chemosensors, porous materials for gas adsorption, stereoselective catalysts for organic reactions, biologically-active compounds, inhibitors of therapeutically-important enzymes, vectors for gene transfection, and fluorescent nanoparticles for cell visualization.

Sorption of volatile organic compounds and ammonia by thin solid films of phosphorylated thiacalixarenes was investigated by the quartz crystal microbalance (QCM), X-ray crystallography and molecular modeling methods The interfacial sorption depends on the number and position (upper or lower rim) of P=O groups on the macrocyclic skeleton, the electronic nature of the substituents at the phosphorus atom. At low concentrations of the analytes their sorption occurs according to the Langmuir isotherm due to specific supramolecular interactions with receptor centers of the thiacalixarenes. The analytes may form either the Host-Guest inclusion complexes stabilized by C-H...π interactions, or extracavity complexes stabilized by hydrogen bonds with oxygen atoms of the peripheral P=O groups. At high concentrations, when the thiacalixarene receptor centers are occupied by the analytes, further sorption occurs nonspecifically according to the linear Henry isotherm due to inclusion of the analytes in voids of the crystal structure of the thiacalixarenes.

It has been previously shown that phosphonic acids covalently attached to the macrocyclic platform of calix[4]arenes are capable of inhibiting alkaline phosphatases. In this paper the effects of the upper-rim functionalized calix[4]arenes on the activity of nucleotide pyrophosphatase/phosphodiesterase 1 (NPP1) have been examined. Aim. To assess the inhibitory potential of calix[4]arene, thiacalix[4]arene and sulfonylcalix[4]arene derivatives against NPP1. Results and discussion. It has been found that calix[4]arene, thiacalix[4]arene, and sulfonylcalix[4]arene tetrakismethylphosphonic acids inhibit NPP1 with the IC50 values in the micromolar range. The derivatives of sulfonylcalix[4]arene demonstrated the selectivity of inhibition of NPP1 over alkaline phosphatases. In addition, sulfonylcalix[4]arene tetrakismethylphosphonic acid was able to inhibit the nucleotide pyrophosphatase/phosphodiesterase activity of the human serum. The possible mechanism of the inhibition has been discussed. Experimental part. The activity of NPP1 was monitored by spectrophotometry measuring the rate of hydrolysis of bis-p-nitrophenyl phosphate. The phosphodiesterase activity of the human serum was assessed in the presence of p-nitrophenyl ester of thymidine-5-monophosphate as a substrate. The homology model of the human NPP1 was generated based on the crystal structure of the murine enzyme. The molecular docking was performed using AutoDock 4.2. Conclusions. The results obtained have shown the ability of sulfonylcalix[4]arene derivatives to inhibit the activity of NPP1 in vitro, including the nucleotide pyrophosphatase/phosphodiesterase activity in the human blood serum.

The Host-Guest complexation of octakis(diphenoxyphosphoryloxy)tetramethylcalix[4]resorcinarene, 5,17-bis-(N-tolyliminomethyl)-25,27-dipropoxycalix[4]arene and 5,11,17,23-tetrakis(diisopropoxyphosphonyl)-25,26,27,28-tetrapropoxycalix[4]arene with a series of 11 phenols (phenol, p-fluorophenol, p-chlorophenol, p-bromophenol, pyrogallol, p-cresol, p-aminophenol, p-nitrophenol, salicylic aldehyde, guaiacol and veratrole) has been studied by the high-performance liquid chromatography (RP HPLC) method. Chromatographic characteristics and log P of industrial phenols have been determined. Using the relationship of the phenol retention factor k’ vs the calixarene concentration in the mobile phase the stability constants of the supramolecular complexes K A (29-331 M -1 ) have been determined. The stability constants of the calixarene complexes show that the Host-Guest interaction strongly depends on the nature of the substituents in the Host and Guest molecules. Calixresorcinarene functionalized by diphenoxyphosphoryl groups and calixarene containing tolyliminomethyl groups formed more stable complexes with some phenols compared to calixarene functionalized by diisopropoxyphosphonyl groups. In accordance with the molecular modeling data the complexation does not change the C2v flattened-cone conformation of the calixarene skeleton. The Host-Guest complexes are stabilized by the intermolecular hydrogen bonds of phenolic OH groups with oxygen atoms of P = O groups at the upper rim, and OH groups at the lower rim of the macrocycle. Hydrophobic interactions also participate in the complexation.

Previously, phosphonic acid derivatives of calix[4]arene and thiacalix[4]arene were found to be potential inhibitors of protein tyrosine phosphatase 1B. In the present paper, the inhibitory activity of unsubstituted sulfonyl-bridget calix[4]arene towards some of the therapeutically important protein tyrosine phosphatases has been established. The obtained results showed that the sulfonylcalix[4]arene is able to inhibit protein tyrosine phosphatase MEG2 with IC50 value in the micromolar range. At the same time, the inhibitor demonstrated lower activity in case of other protein tyrosine phosphatases such as PTP1B, MEG1, TC-PTP, SHP2, and PTPβ. The performed molecular docking indicated that the inhibitor binds to the active site region of MEG2 and PTP1B with WPD-loop in the open conformation.

Host-Guest complexation of octakis(diphenoxyphosphoryloxy)tetramethylcalix[4]resorcinarene CRA and 5,17-bis-(N-tolyliminomethyl)-25,27-dipropoxycalix[4]arene CA with bio relevant aromatic, pyridine and diterpenoid carboxylic acids in water-organic solution had been studied by the RP HPLC and molecular modelling methods. The stability constants KA (387-1914 М-1) of the supramolecular complexes had been determined. It was shown the Host-Guest interactions are depended on structure of the Host molecules and log P values of the Guests. The complexation is determined by the hydrogen bonds of the COOH group of the carboxylic acids with P=O oxygen atom of diphenoxyphosphoryl group of the calixresorcinarene CRA, and oxygen or nitrogen atoms located on the lower or the upper rim of the calixarene CA.

Extraction of 241Am and 152Eu from alkaline carbonate solutions with solutions of functionalized calix[4]arenes and their nonmacrocyclic analogs in m-nitrobenzotrifluoride was studied. The dependence of the distribution ratios and separation factors of the radionuclides on pH of the aqueous phase in the interval from 9.8 to 13.5 and on the position and electronic nature of functional groups (alkyl, pyridine, phosphoryl) in the calixarene core was examined. The composition of the extractable solvates of americium and europium with functionalized calix[4]arenes was determined. From both alkaline and nitric acid solutions, calixarenes extract americium more efficiently than their nonmacrocyclic analogs do. The calix[4]arene with the pyridine functional group exhibits the highest selectivity, with the Am/Eu separation factor exceeding 3. Calix[4]arenebis-(methanediphosphonates) extract europium and americium from both alkaline and nitric acid solutions with similar magnitude of the cooperative effect.

In the present work, the derivatives of calix[4]arene, thiacalix[4]arene, and sulfonylcalix[4]arene bearing four methylene(phenyl)phosphinic acid groups on the upper rim of the macrocycle were synthesized and studied as inhibitors of human protein tyrosine phosphatases. The inhibitory capacities of the three compounds towards PTP1B were higher than those for protein tyrosine phosphatases TC–PTP, MEG1, MEG2, and SHP2. The most potent sulfonylcalix[4]arene phosphinic acid displayed Ki value of 32 nM. The thiacalix[4]arene phosphinic acid was found to be a low micromolar inhibitor of PTP1B with selectivity over the other PTPs. The kinetic experiments showed that the inhibitors compete with the substrate for the active site of the enzyme. Molecular docking was performed to explain possible binding modes of the calixarene-based phosphinic inhibitors of PTP1B.

All three possible inherently chiral (cS)-propyloxy-octyloxy-calix[4]arene acetic acids were synthesized and their absolute configuration was proved. Complexation of the calix[4]arene acetic acids with a number of chiral compounds have been studied by molecular modeling and 1H NMR spectroscopy and enantioselectivity of binding of R- and S-forms of 2-aminobutanol was found.

The hydrolysis of fluorogenic substrates of fluorescein diester series is a popular and well-documented indicative reaction used in enzyme biochemistry for cholinesterase systems and related fields. The overwhelming majority of studies have been performed using the fluorescence spectroscopy and conventionally considering this two-step reaction as a single-step one. We developed a spectrophotometry-based approach for the separate determination of the rate constants of the first and second hydrolysis steps of fluorescein diesters, such as diacetyl- and dilaurylfluorescein. This approach was applied to micellar solutions of cationic colloidal surfactants and calixarenes in water. Cationic surfactants cetyltrimethylammonium bromide, cetyl-N-pyridinium chloride, cationic Gemini surfactant 16–4–16 bromide, di-n-tetradecyldimethylammonium bromide and a zwitterionic surfactant cetyldimethylammonium propanesulfonate were used. As amphiphilic cationic calixarenes, the wide rim choline or imidazolium derivatives of calix[4,6]arenes decorated at the narrow rim with methyl, propyl, hexyl, octyl, and dodecyl tails in form of tetra- and hexachlorides were used. These systems display marked acceleration of the hydrolysis reaction of diacetylfluorescein in water. The results were compared with the kinetic data in 50 mas. % ethanol. Non-ionic surfactant Triton X-100 displays no influence on kinetics, whereas an anionic surfactant sodium laurylsulfate strongly reduces the reaction rate. In the presence of calixarene aggregates, an expressed catalytic effect was observed for diacetylfluorescein, but not for dilaurylfluorescein. For instance, the rate constants of stepwise hydrolysis of diacetylfluorescein increase by ca. 200–750 times on going from water to aqueous solutions of 5,11,17,23-tetra(N,N-dimethyl-N-hydroxyethylammonium)methylene-25,26,27,28-tetradodecyl-oxycalix[4]arene tetrachloride. At the same time, a distinct macrocyclic effect of calixarene was also observed: the micelles of the “quarter” compound N,N-dimethyl-N-hydroxyethyl-4-dodecyloxybenzylammonium chloride also accelerate the reaction, but in a much less expressed manner.

Grafting of a carbamoylmethylphosphine oxide (CMPO) calix[4]arene ligand to the silica surface yields an anchored host site that displays an unusual 22.4-fold higher affinity (kD value) for EuIII relative to AmIII. This selective cation recognition is in stark contrast to a more flexible propoxy-tethered CMPO-calix[4]arene site on silica.

Комплексоутворення типу Гість-Господар oктакіс-(дифеноксифосфорилокси)-тетраметилкалікс[4]резорцинарену (CR) та 5,17-біс-(N-толілімінометил)-25,27-дипропоксикалікс[4]aрену (CA) з 6 дитерпеноїдними (смоляними) кислотами було досліджено методом обернено-фазної високоефективної рідинної хроматографії (ОФ ВЕРХ). Визначені хроматографічні характеристики (час утримання tR тa фактор утримання k’) смоляних кислот. Розраховано значення ліпофільності log P смоляних кислот тa констант зв’язування KA комплексів (395-682 М-1 для CR тa 844-1268 М-1 для CA), а також значення вільних енергій Гіббса ∆G (-14.79 – -16.14 кДж/моль для CR тa -16.70 – -17.67 кДж/моль для CA) із смоляними кислотами. Молекулярне моделювання комплексів CA вказало на присутність водневих зв’язків між карбоксильними групами кислот тa атомами азоту іміно-груп верхнього вінця CA макроцилу або атомами кисню ОН груп його нижнього вінця. Молекулярне моделювання комплексів CR вказало на присутність водневих зв’язків між карбоксильними групами кислот тa атомами кисню дифеноксифосфорилокси-груп верхнього вінця макроциклу CR. Здійснено оцінку впливу log P на константи зв’язування KA комплексів CR/CA. Лінійна залежність КА від log P кислот вказує на роль сольвофобних взаємодій на комплексоутворення. Встановлено взаємозв’язок між супрамолекулярними (KA) тa фізико-хімічними (log P, pKa) характеристиками кислот., The Host-Guest complexation of octakis-(diphenoxyphosphoryloxy)tetramethylcalix[4]resorcinarene (CR) and 5,17-bis-(N-tolyliminomethyl)-25,27-dipropoxycalix[4]arene (CA) with 6 diterpenoid (resin) acids has been studied by the reversed phase high-performance liquid chromatography (RP HPLC). The chromatographic characteristics (retention time tR and retention factor k’) of resin acids have been determined. The lipophilicity values log P of the acids, binding constants KA (395-682 M-1 for CR and 844-1268 M-1 for CA), as well as Gibbs free energies ∆G (-14.79 – -16.14 kJ/mol for CR and -16.70 – -17.67 kJ/mol for CA) of the complexes with resin acids have been calculated. Molecular modelling of CA complexes has revealed the presence of hydrogen bonds between carboxylic groups of acids and nitrogen atoms of imino groups at the upper rim or oxygen atoms of the hydroxyl groups at the lower rim of the CA macrocycle. Molecular modelling of CR complexes has shown the presence of hydrogen bonds between carboxylic groups of acids and oxygen atoms of diphenoxyphosphoryloxy groups at the upper rim of the CR macrocycle. The effect of log P values on KA values of the CR/CA complexes has been assessed. The linear dependence of the binding constants on the acid lipophilicity indicates a significant role of solvophobic interactions on the complexation. The relationship between supramolecular (KA) and physicochemical (log P, pKa) characteristics of acids has been determined., Комплексообразование типа Гость-Хозяин oктакис-(дифеноксифосфорилокси)-тетраэтилкаликс[4]резорцинарена (CR) и 5,17-бис-(N-толилиминометил)-25,27-дипропоксикаликс[4]aрена (CA) с 6 дитерпеноидными ( смоляными) кислотами было исследовано методом обращенно-фазной высокоэффективной жидкостной хроматографии (ОФ ВЭЖХ). Определены хроматографические характеристики (время удерживания tR и фактор удерживания k’) смоляных кислот. Рассчитаны значения липофильности log P смоляных кислот и констант связывания KA их комплексов (395-682 М-1 для CR и 844-1268 М-1 для CA), а также значения свободных энергий Гиббса ∆G (-14.79 – -16.14 кДж/моль для CR и -16.70 – -17.67 кДж/моль для CAL) со смоляными кислотами. Молекулярное моделирование комплексов CA показало наличие водородных связей между карбоксильными группами кислот и атомами азота имино-групп верхнего обода макроцикла CA или атомами кислорода гидроксильных групп его нижнего обода. Молекулярное моделирование комплексов CR показало наличие водородных связей между карбоксильными группами кислот и атомами кислорода дифеноксифосфорилокси-групп верхнего обода макроцикла CR. Оценено влияние log P на константы связывания KA комплексов CR/CA. Линейная зависимость КА от log P кислот свидетельствует о влиянии сольвофобных взаимодействий на процесс комплексообразования.

The Mitsunobu alkylation of 4-tert-butylcalix[4]arene with (S)-(2-diphenylthiophosphinoferrocenyl)methanol followed by desulfuration of the thiophosphine unit using tris(dimethylamino)phosphine afforded enantiomerically pure calixarene mono- and di(ferrocenylphosphine) ligands in high yields. The calixarene mono(ferrocenylphosphine) ligands exhibited good catalytic activity but low atropoenantioselectivity when used in the asymmetric Suzuki–Miyaura coupling reaction of 1-naphthaleneboronic acid and 1-bromo-2-methylnaphthalene. However, the di(ferrocenylphosphine) ligand displayed both good catalytic activity and enantioselectivity (ee values up to 86 %) when employed in the asymmetric Tsuji–Trost allylic alkylation of 1,3-diphenylprop-2-enyl acetate with dimethyl malonate.

The aim of the research was to study a potential antithrombotic sodium salt of calix[4]arene-methylenebis-phosphonic acid (С-145) — on activation and aggregation of platelets in vivo, as well as on proliferation and apoptosis of endothelial cells in the cell culture. Effects of calix[4]arene С-145 estimated in vitro after addition to the platelet rich plasma, and in vivo after intravenous injection into rabbit bloodstream in equivalent amounts (46 μM). Aggregation of platelets was induced by adenosine diphosphate and detected using aggregometer Solar AP2110. Platelet shape and cytoplasmic granularity were monitored on COULTER EPICS XL Flow Cytometer. The level of tissuetype plasminogen activator — tPA — was estimated using enzyme-linked immunosorbent assay ELISA. Effects of calix[4]arene C-145 on culture of endotelial cells cells was studied using 3-(4,5-Dimethylthiazol2-yl)-2,5-Diphenyltetrazolium Bromide — MTT-test. The population of proliferative pool of cells (G2/ M+S) was determined using flow cytometry. Aggregometry and flow cytometry showed that calix[4]arene C-145 did not activate platelets nor affect their aggregation in vitro. However intravenous injection of calix[4]arene C-145 into the bloodstream of healthy rabbits leads to strong inhibition of platelet aggregation and changes of shape and granularity of most of the platelets after 2 hours of administration. Any additional appearance of endothelial cells activation marker tPA in vivo and any inhibition of calix[4]arene C-145 on proliferation of endothelial cells in cell culture did not observe. So calix[4]arene C-145 had strong anti-platelet effect in vivo that was not a result of their direct action on platelets or endothelial cells in vitro. This allowed to assume the possibility of calix[4]arene C-145 use as an effective antithrombotic agent., Целью работы было изучение действия потенциального антитромботического агента — натриевой соли каликс[4]арен-метилен-бисфосфоновой кислоты — каликс[4]арена С-145 на активацию и агрегацию тромбоцитов in vivo, а также на пролиферацию и апоптоз эндотелиоцитов в тканевой культуре. Эффекты каликс[4]арена С-145 оценивали in vitro после добавления в плазму крови, богатую тромбоцитами, а также in vivo после внутривенного введения в кровоток кролика в эквивалентных количествах (46 μМ). Агрегацию тромбоцитов индуцировали ADP и определяли с помощью агрегометра Solar AP2110. Форму и гранулярность цитоплазмы тромбоцитов устанавливали проточным цитометром COULTER EPICS XL. Уровень активатора плазминогена тканевого типа — tPA — измеряли методом иммуноэнзимного анализа ELISA. Эффекты каликс[4] арена C-145 на культуру эндотелиоцитов изучали с помощью 3-(4,5-диметилтиазол-2-ил)-2,5диметилтетразолия бромида — МТТ-теста. Популяцию пролиферативного пула (G2/M+S) клеток эндотелия определяли с применением цито метрии. Методами агрегатометрии и цитометрии установлено, что каликс[4]арен С-145 не активирует тромбоциты и не влияет на их агрегацию in vitro. Однако уже через два часа после введения каликс[4]арена С-145 здоровым лабораторным кролям тромбоциты теряли способность агрегировать, а пул интактных тромбоцитов уменьшался в два раза. В то же время не наблюдали выброса в плазму крови маркера активации эндотелиоцитов tPA in vivo, а также ингибирования пролиферации эндотелиоцитов в культуре клеток. Таким образом, каликс[4]арен С-145 обладает значительным антитромбоцитарным эффектом in vivo, не действуя непосредственно на тромбоциты и эндотелиоциты in vitro. Такие свойства каликсарена позволяют рассматривать возможность его применения в качестве эффективного антитромботического агента.

We investigated the influence of calixarene C-90 and IPT-35 on plasma membrane Ca2+- pumping АТРase (PMCA), intracellular calcium homeostasis and myometrium smooth muscle strain contractions. It has been shown that both effectors (100 μM) affect PMCA enzymatic activity: calixarene C-90 inhibits it by 75% and IPT-35 activates it by 40%. These compounds don't affect the Mg2+-АТРase, Mg2+-independent Са2+-АТРase and Na+,K+-АТРase enzymatic activities. C-90 inhibition coefficient I0.5 magnitude was approximately 20 μM and the Hill coefficient nH was 0.55. For IPT-35 activation, constant А0.5 was 6.4 and nH was 0.7. Mathematical modeling demonstrated the implication of calixarene C-90 on unexcited myocytes, which allows for a precise change in cytoplasm Ca2+ concentration and an influence on basal muscle tonus. By the same method, we determined that IPT-35 has a little influence on Ca2+ concentration in unexcited myocytes. It was also shown that calixarene C-90 in vitro can increase velocity of oxytocin-initiated contractions, whereas IPT-35 can suppress this aforementioned parameter. These results are promising for the design of new pharmacological compounds as better regulators of uterine contractions. Calixarene C-90 can be used in obstetric cases for the simultaneous use of oxytocin for enhancing uterine contractions, and IPT-35 for its antispasmodic effect on uterine tone.

International audience; A facile method for the preparation of enantiomerically pure inherently chiral calix[4]arene phosphonic acid (cR,pR)-7 in four steps starting from the readily available and previously synthesized (cS)-enantiomer of calix[4]arene acetic acid 1 or its methyl ester 2 was developed. The first tests of this unique calixarene Brönsted acid with inherent chirality in organocatalysis of the aza-Diels–Alder reaction of imines with Danishefsky’s diene and epoxide ring opening by benzoic acid were performed. The calixarene phosphonic acid (cR,pR)-7 shows good catalytic activities but with low enantioselectivities in these reactions.

A method for the synthesis of calix[4]arenes possessing methylenebisphosphonic acid groups capable of forming supramolecular complexes with amino acids, and anchoring 3-methylsulfidopropoxy groups ...

Numerous female reproductive abnormalities are caused by uterine smooth muscle (myometrium) disorders. Heavy metals have an adverse effect on the contractility of the uterine smooth muscle. Although zinc is an essential biogenic element for most of the organisms, high doses of this element are toxic. The study of 0.5−5 mM Zn2+ effect on myosin S1 ATPase activity from the uterus found that 5 mM Zn2+ cations have the most pronounced inhibitory effect. The calculation of the kinetic parameters (K m and V max, ATP) revealed that the apparent maximum velocity of the hydrolysis ATP catalyzed by myosin in the presence of 5 mM Zn2+ decreased by 1.6 times. The value of К m for ATP hydrolysis by myosin S1 in the presence of Zn2+ does not change statistically, although it tends to decrease. It was determined that uterine myosin S1 ATPase activity does not depend on the concentration of Mg2+ in the presence of 5 mM Zn2+. Also, it was demonstrated that tetrahydroxythiacalix[4]arene-tetrasulfosphonate (C-798) and tetrahydroxythiacalix[4]arene-tetraphosphonate (C-800) restored myosin S1 ATPase activity to the control level in the presence of 5 mM Zn2+. One of the most probable mechanisms of restoring the action of these thiacalix[4]arenes protective effect is based on its ability to chelate heavy metal cations from the incubation medium. The molecular docking of C-798 and C-800 into the myosin S1 region showed that these thiacalix[4]arenes could interact with Zn cation bond by myosin amino acid residues near the ATPase active site. Therefore, thiacalix[4]arenes may weaken the interaction between this cation and myosin S1. It was speculated that the obtained results could be used for further research with the aim of using this thiacalix[4]arenes as pharmacological compounds in the case of poisoning with high concentrations of zinc.

All six possible stereoisomers of calix[4]arenes with four different substituents on the lower rim of the macrocycle have been synthesized by stepwise alkylation of the hydroxyl groups of tert-butylcalix[4]arene using (R)- or (S)-1-phenylethylamide groups as chiral auxiliaries. They form three enantiomeric pairs, as confirmed by the values of their specific rotation.

Macrocycles have been attracting increasing attention as scaffolds for preparation of non-viral vectors for gene delivery. Here, following our earlier report, a series of amphiphilic calixarenes bearing cationic choline or N-(2-aminoethyl)-N,N-dimethylammonium groups at the upper rim and alkyl chains at the lower rim were synthesized. The effect of the length of aliphatic chains and the structure of the head group on their self-assembly, interaction with DNA, properties of their DNA complexes, transfection efficiency and cytotoxicity was studied. It was found that longer alkyl chains favor formation of small virus-sized DNA nanoparticles with low polydispersity. Moreover, longer alkyl chains, such as dodecyl groups, significantly improved the transfection efficiency, so transfection was observed in the presence of fetal bovine serum as well as with or without a helper lipid. Finally, we observed that the cytotoxicity of these calixarenes clearly decreased with increase of the chain length. On the other hand, the presence of four additional amino groups, which could be protonated at pH < 7, affected only the stoichiometry of the complexes with DNA without influencing their transfection efficiency or cytotoxicity. The results obtained provide new insights for designing non-viral vectors based on macrocyclic molecules.

Host-Guest complexation of calixarene-bis-hydroxymethylenediphosphonic acid with 17 amino acids in water solution had been studied by the RP HPLC and molecular modelling methods. It had been shown the binding constants of the complexes are depended on the nature of the amino acid residue, log P and pKa of the acids. The complexation is mainly determined by the electrostatic interactions between the positively charged nitrogen atom of the amino acid and the negatively charged oxygen atom of phosphonic acid residue of the calixarene, the Host-Guest p-p, СН-p and solvophobic interactions.

Heavy metals have a negative effect on the contractility of uterine smooth muscles (myometrium), these effects can lead to various pathologies of a women reproductive system. To overcome these effects the methods for correcting the myometrium contractile activity are to be developed. Catalyzed by myosin ATPase ATP hydrolysis is the most important reaction in the molecular mechanism of myo­metrium contraction. We have found an inhibitory effect of 0.03-0.3 mM Ni2+, Pb2+ and Cd2+ on enzymatic hydrolysis of ATP by myosin subfragment-1 obtained from swine uterine smooth muscles. We have demonstrated that 100 µM thiacalix[4]arene-tetrasulphonate (C-798) recovered to the control level of ATPase activity of myosin subfragment-1 in the presence of heavy metal cations. One of the most probable mechanisms of C-798 corrective activity is based on its ability to chelate heavy metals, thus cations Pb, Cd and Ni can be removed from the incubation medium. Computer simulation has demonstrated that the protective effect of C-798 may also be the result of weakening the interaction of heavy metal ions with amino acid residues of the myosin molecule near the active site of ATP hydrolase. The obtained results can be used for further research aimed at assessing the prospects of thiacalix[4]arene-tetrasulfonate as pharmacological compounds.

The article is devoted to application of chromatography in analytical and supramolecular chemistry of calixarenes. The chromatographic analysis of tert -butylhydroxycalix[ n ]arenes and their functional derivatives as well as enantioseparation of different types of chiral calixarenes is described. An application of the chromatographic method for investigation of the calixarene complexing properties with respect to organic compounds of different classes is presented. Dependence of the stability constants of the supramolecular Host–Guest inclusion complexes on the structure of calixarene-Host and nature of molecule-Guest is discussed. An application of calixarenes as stationary phases in liquid and gas chromatography as well as their use as selective additives to mobile phases in liquid chromatography is described.

In experiments on the suspension of myometrium cell plasma membrane, processed by 0.1% digitonin, the inhibitory action of calix[4]arene C-90 (5,11,17,23-tetra(threeftor)methyl(phenilsulphonilimino)-methylamino-25,26, 27,28-tetrapropoxy-calix[4]arene) on the activi­ty of Ca2+,Mg2+-ATPase was investigated. The authors also examined the influence of calix[4]arene in different concentration on affinity of enzyme (Ca2+,Mg2+-ATPase) for the ATP and ions of Mg and Ca, and its influence on cooperative effect and maximum velocity of ATP hydrolysis. It is shown that calix[4]arene does not influence the affinity of Ca2+,Mg2+-ATPase for the ATP, which means that these two compounds have different binding centers­. Also calix[4]arene has no influence on affinity and cooperative effect of Ca ions, if it is used in concentration lower than 50 µM. Calix[4]arene slightly increases coefficient of Ca2+,Mg2+-ATPase activation by magnesium chloride. In all three cases, where ATP, Mg and Ca ions are used to test the impact of calix[4]arene, maximum velocity of ATP hydrolysis significantly decreases. All these results clarify that calix[4]arene implements its inhibitory action through mechanism of uncompetitive inhibition of Ca2+,Mg2+-ATPase activity.

Water-soluble cationic calixarenes readily form aggregates in water. The properties of these aggregates, however, markedly vary along with alterations in the molecular structure. In a set of our recent studies, such aggregates were examined by various methods, and first of all using acid–base indicator dyes. The latter acted in fact as monoprotic acids exhibiting one color transition, and their pKa shifts against the values in water were relatively close for different calixarenes. In the present paper, we report the behavior of a much more complicated dye, fluorescein, and two relative compounds, in aqueous solutions of two cationic calix[4]arenes. The last named possess four choline groups on the upper rim and the sole difference is the length of the alkoxy groups at the lower rim: O(CH2)2CH3 and O(CH2)7CH3. In water, both calixarenes form aggregates of similar size and with similar zeta-potential. However, their influence on the acid–base and tautomeric equilibria of fluorescein clearly demonstrate that the aggregates of the long-tailed calixarene resemble the common micelles of colloidal surfactants to a higher degree than those of tetrapropyloxy compound.

The success of gene therapy depends largely on the development of new efficient gene delivery vehicles. The emerging class of molecules for this application is macrocycles that feature persistent shape, thus ensuring higher level of supramolecular organization of the DNA complexes. The review focuses on recently developed calixarenes and close analogues as gene delivery vectors, their chemistry, ability to compact nucleic acids, transfection ability in vitro and cytotoxicity. Their fixed conformation with the possibility of multiple functional groups at the upper and lower rims allows preparation of cone-shaped macromolecules capable of programmed hierarchical assembly in the presence of DNA. It is shown that specially designed calixarenes, particularly those having amphiphilic structure with clustered DNA binding units, can form small virus-sized DNA nanoparticles with well-defined architecture, high transfection efficiency and low toxicity. The field is still largely underexplored so that there is a lot of room for further improvement of the molecular design of calixarenes. Moreover, their evaluation in vivo on animals will be an important step towards their validation for gene therapy.

A series of thiacalix[4]arenes bearing one, two or four chelating dibutylphopshinoylmethoxy groups have been synthesised and studied in the context of this paper. The synthesis consisted of precise Williamson alkylation of thiacalixarene tetrols with tosylate of dibutylhydroxymethyl phosphine oxide in the presence of alkali metal carbonates or sodium hydride. Stereochemical yield of the reaction (cone or 1,3-alternate conformer) depends on the nature of alkali metal. Small-sized ‘hard’ sodium cation organises the macrocyclic platform in the cone conformation, but larger and ‘soft’ potassium and cesium cations stabilise the macrocycle in the 1,3-alternate conformation. All synthesised compounds (except monophosphine monoxide) possess either moderate or high extraction ability towards pertechnetate ion. The cone-shaped thiacalix[4]arene tetraphosphine tetraoxide due to cooperative (macrocyclic) effect of eight oxygen atoms of the phosphinoylmetoxy-binding groups effectively extract spherical americium, euro...

Calix[4]arene are known to be a promising scaffold for designing inhibitors of protein tyrosine phosphatases. In this work calix[4]arene mono- and bis-α-hydroxymethylphosphonic acids have been tested in vitro for the inhibitory activity against some therapeutically important protein tyrosine phosphatases. The results obtained have shown that these macrocyclic compounds can inhibit CD45, PTP1B, and SHP2 with IC50 values in the micromolar range. At the same time the inhibitors have demonstrated lower activity toward other protein tyrosine phosphatases such as TC-PTP and PTPβ. It has been found that mono-substituted calix[4]arene is more potent inhibitor of CD45 than the bis-substituted one and shows about 2-15 fold selectivity over TC-PTP, PTPβ, SHP2 and PTP1B. Model 4-hydroxyphenyl-α-hydroxymethylphosphonate displays at least one order lower activity than the phosphonate derivatives of calix[4]arene. Thus, the combination of a macrocyclic platform and α-hydroxymethylphosphonate group is essential for the inhibition activities of these compounds. Computer-simulated docking studies have been performed using AutoDock 4.2 programme by the example of PTP1B. The data obtained indicate that the inhibitors can bind in the active site of the enzyme. To clarify the inhibition mechanism the possible enzyme-inhibitor complexes have been considered using several crystal structures of PTP1B and all stereoisomeric forms of the inhibitors.

The synthetic approaches to mono-isopropoxytrihydroxycalix[4]arenes bearing two or three diphenylphosphino groups at the upper macrocycle rim were elaborated. Due to reactive hydroxyl groups at the lower rim capable of binding with silica gel surface, the calixarenes, especially the enantiomerically pure inherently chiral diphosphinocalixarene, are promissing ligands for creation of hybride organic–inorganic metallocomplexing catalysts of organic (asymmetric) reactions.

The crystal structures of a new type of coordination polymer formed by the high-spin form of a hexaazamacrocyclic nickel(II) complex and a lower rim calix[4]arene tetracarboxylate trianion (2) as well as the perchlorate salt of the low-spin form of this macrocyclic cation (1) are reported. The porosity of the network is characterized by the presence of polar and non-polar voids formed by carboxylate substituents/azamacrocyclic cations and aromatic/tert-butyl substituents of the calix[4]arene, respectively.

This is the pre-peer reviewed version of the following article: Shulov, I.; Rodik, R. V.; Arntz, Y.; Reisch, A.; Kalchenko, V. I.; Klymchenko, A. S.: Protein-Sized Bright Fluorogenic Nanoparticles Based on Cross-Linked Calixarene Micelles with Cyanine Corona. Angew. Chem.Int. Ed. 2016, 55, 15884-15888, which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1002/ange.201609138/abstract. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.