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Ferrocene is useful in modern organometallic chemistry due to its versatile applications in material sciences, catalysis, medicinal chemistry, and diagnostic applications. The ferrocene moiety can potentially serve many purposes in therapeutics and diagnostics. In the course of this study, (6-bromo-1-oxohexyl)ferrocene was combined with dimercaptomaleonitrile sodium salt to yield a novel maleonitrile derivative. Subsequently, this compound was subjected to an autocyclotetramerization reaction using the Linstead conditions in order to obtain an octaferrocenyl-substituted magnesium(II) sulfanyl porphyrazine. Following that, both compounds—the maleonitrile derivative and the porphyrazine derivative—were subjected to physicochemical characterization using UV-Vis, ES-TOF, MALDI-TOF, and one-dimensional and two-dimensional NMR spectroscopy. Moreover, the sulfanyl porphyrazine was subjected to various photophysical studies, including optical absorption and emission measurements, as well as the evaluation of its photochemical properties. Values of singlet oxygen generation quantum yields were obtained in different organic solvents. The electrochemical properties of the synthesized compounds were studied using cyclic voltammetry. According to the electrochemical results, the presence of electron-withdrawing oxohexyl groups attached to ferrocene afforded significantly more positive oxidation potentials of the ferrocene-based redox process up to 0.34 V vs. Fc+/Fc. [ABSTRACT FROM AUTHOR]

Purple crystals of the title compound, C50H44Cl4N4S2 were obtained from the reaction of 2,5-bis(4-propyl-1H-pyrrol-2-yl)thiophene and 3,5-dichlorobenzaldehyde in the presence of trifluoroacetic acid for 3 h and subsequent addition of p-chloranil. The macrocycle in the title compound can be described as a highly planar structure wthe the average deviation of the 32 macrocyclic atoms from the least-squares plane being 0.0416 Å. Its molecular conformation is stabilized by two intramolecular N—H...N bonds and a three-dimensional network is formed by C—H...π interactions.

[Display omitted] • Residual drugs or poisons may become "invisible killers", producing unexpected side effects. • The development of small molecule antagonists that rely on influencing drug-receptor interactions is too difficult. • This review answers the questions about how to design supramolecular antagonists based on macrocyclic host compounds. In the interdisciplinary domains of medicine and chemistry, addressing the issue of residual drugs (toxicants) that fail to fully exert therapeutic effects while potentially inducing toxic side effects has become increasingly critical. Researchers are actively seeking innovative solutions to this multifaceted challenge. Conventional small-molecule antagonists, commonly used in clinical settings, typically depend on "drug–receptor interactions" yet pose substantial developmental challenges. Recent advancements in the investigation of macrocyclic host compounds present a promising alternative. By leveraging the principles of host–guest chemistry, these macrocyclic hosts form stable inclusion complexes with residual drugs (toxicants), thereby decreasing their free concentration in the bloodstream and effectively mitigating associated toxic side effects. Consequently, macrocyclic host compounds represent a novel class of supramolecular antagonists (SAs). This article reviews recent progress in the application of macrocyclic host molecules—such as cyclodextrin, calix[ n ]arene, pillar[ n ]arene, and cucurbit[ n ]uril—as SA and examines current issues and future development prospects within the field. [ABSTRACT FROM AUTHOR]

In this study, we examine macrocyclic compounds to determine whether they can provide a safer replacement and stable complex for BPA in thermochromic dyes. To achieve this objective, a series of macrocyclic compounds, Methyl-N-benzylhexahomotriazacalix[3]arene (MeAC3), p-Chloro-N-benzylhexahomo-triazacalix[3]arene (ClAC3), α-Cyclodexdrin (α-CD), β-Cyclodexdrin (β-CD), p-tert-Butylthiacalix[4]arene (TC4), Calix[4]arene (C4), and Resorcin[4]arene (RC4), were synthesized. Among these macrocyclic compounds, RC4 was determined to be the most appropriate candidate to replace BPA as the developer material used in thermochromic dyes. In tests of prepared thermochromic dyes, RC4 had results similar to those of BPA, achieving the best protonation/deprotonation equilibria and providing a dark contrast with the thermochromic dye. DFT calculations also showed stable complexes between RC4 and CVL via hydrogen-bond interactions. [ABSTRACT FROM AUTHOR]

Iron–nitrogen doped carbon (Fe/N/C) electrocatalysts are among the most promising materials to replace Pt for the oxygen reduction reaction (ORR). Up to now, most work has been devoted to improving the performance of Fe/N/C catalysts by material design, while ignoring the design of the electrode/electrolyte interface environment. Considering the superior ORR performance of Fe/N/C catalysts in alkaline electrolyte, we attempt to construct a proton-deficient environment at the electrode surface to raise the local pH value. An anion-exchange ionomer with H+ blocking ability was chosen as the binder of the iron phthalocyanine (FePc) catalyst, a model molecule for Fe/N/C. The anion-exchange ionomer can increase the interface pH value as compared with commonly used Nafion binder, which was verified by the electrochemical shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) technique with CO32–/HCO3– as a probe. This strategy significantly improves the ORR activity and stability of the FePc catalyst in acidic medium.

Ferrocene is useful in modern organometallic chemistry due to its versatile applications in material sciences, catalysis, medicinal chemistry, and diagnostic applications. The ferrocene moiety can potentially serve many purposes in therapeutics and diagnostics. In the course of this study, (6-bromo-1-oxohexyl)ferrocene was combined with dimercaptomaleonitrile sodium salt to yield a novel maleonitrile derivative. Subsequently, this compound was subjected to an autocyclotetramerization reaction using the Linstead conditions in order to obtain an octaferrocenyl-substituted magnesium(II) sulfanyl porphyrazine. Following that, both compounds—the maleonitrile derivative and the porphyrazine derivative—were subjected to physicochemical characterization using UV-Vis, ES-TOF, MALDI-TOF, and one-dimensional and two-dimensional NMR spectroscopy. Moreover, the sulfanyl porphyrazine was subjected to various photophysical studies, including optical absorption and emission measurements, as well as the evaluation of its photochemical properties. Values of singlet oxygen generation quantum yields were obtained in different organic solvents. The electrochemical properties of the synthesized compounds were studied using cyclic voltammetry. According to the electrochemical results, the presence of electron-withdrawing oxohexyl groups attached to ferrocene afforded significantly more positive oxidation potentials of the ferrocene-based redox process up to 0.34 V vs. Fc+/Fc.

[Display omitted] • A novel sort of macrocyclic CQDs sensor from HemiQ[6] has been developed. • The CQDs sensors exhibited a highly sensitive and real-time response to Pb2+. • The CQDs suggested a potential application for the efficient determination of Pb2+. A macrocyclic compound, hemicucurbit[6]uril (HemiQ[6]), is employed as the carbon source to produce a novel sort of carbon quantum dots (CQDs) with blue fluorescence in aqueous solution. The CQDs are fully identified by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Nuclear Magnetic Resonance (NMR), zeta potential, ultraviolet/visible (UV–vis) and photoluminescence spectroscopy (PL). The nanomaterial is developed for the analysis of Pb2+ in the light of the Resonance Rayleigh scattering (RRS) changes with the increasing Pb2+ concentration. The proposed probe emerges a high selectivity to Pb2+ and excellent sensitivity in the linear concentration range of 0–6 μM with a detection limit low to 0.42 μM, which is superior to the previous values of Pb2+ sensors, as well as the good anti-interference ability is confirmed by the specifical response to Pb2+ in the presence of other metal cations. Therefore, the proposed analysis of Pb2+ is explored for the application in real samples of tap water and lake water, in satisfied results of acceptable recoveries. [ABSTRACT FROM AUTHOR]

The profound pharmacological properties of macrocyclic compounds have led to their development as drugs. In conformationally pre-organized ring structures, the multiple functions and stereochemical complexity provided by the macrocycle result in high affinity and selectivity of protein targets while maintaining sufficient bioavailability to reach intracellular locations. Therefore, the construction of macrocycles is an ideal choice to solve the problem of "undruggable" targets. Inspection of 68 macrocyclic drugs on the market showed that 10 of them were used to treat cancer, but this structural class still has been poorly explored within drug discovery. This perspective considers the macrocyclic compounds used for anti-tumor with different targets, their advantages and disadvantages, and the various synthetic methods of them. [ABSTRACT FROM AUTHOR]

The profound pharmacological properties of macrocyclic compounds have led to their development as drugs. In conformationally pre-organized ring structures, the multiple functions and stereochemical complexity provided by the macrocycle result in high affinity and selectivity of protein targets while maintaining sufficient bioavailability to reach intracellular locations. Therefore, the construction of macrocycles is an ideal choice to solve the problem of “undruggable” targets. Inspection of 68 macrocyclic drugs on the market showed that 10 of them were used to treat cancer, but this structural class still has been poorly explored within drug discovery. This perspective considers the macrocyclic compounds used for anti-tumor with different targets, their advantages and disadvantages, and the various synthetic methods of them.

Nearly 80 years following the initial synthesis of cucurbiturils, its structure was finally revealed in 1981, which discovery opened the field for further investigation. As a result, the scope of available sizes and varieties of cucurbiturils has grown profoundly in the last four decades, leading to a large number of potential applications, including cucurbiturils in catalysis as supramolecular additives due to the capability of supramolecular binding to certain substrates. Owing to their polar portals and non-polar cavity, cucurbiturils can have an eclectic range of binding versatile guests of different shapes and electronic structures, making them especially attractive for supramolecular catalysis with a wide range of possible reaction types. This review concisely discusses the unique structure and properties of cucurbiturils, and highlights their use as molecular containers in terms of supramolecular interactions in catalytic reactions such as photoreaction, solvolysis, oxidation, metal-assisted catalysis, bromination, Diels–Alder, xanthene synthesis, and Schiff base reaction. [ABSTRACT FROM AUTHOR]

We have developed laser desorption ionization mass spectrometry (LDI-MS) of organic molecules encapsulated in a crystalline sponge (CS). Cyclic organic compounds 1,2,3,4,5-pentamethylcyclopentadiene, zerumbone, and muscone were encapsulated in CS as guest regardless of guest crystallization. Single-crystal X-ray analysis closely scrutinized the position of the guest in the pore and the interaction between the guest and the CS framework. After single-crystal X-ray analysis, the same single crystal was subjected to LDI-MS. Ionization efficiency differed markedly depending on whether π−π interaction existed or not. It is obvious that π−π interaction is the key to transferring laser energy from the CS framework to the guest for the ionization of molecule encapsulated in CS. The results suggest the importance of controlling the positions of analyte and matrix as well as noncovalent interactions, such as hydrogen bonding interaction, electrostatic interaction, and so on. Image 1 • Crystalline sponge can encapsulate three different sized cyclic organic compounds. • Single crystal X-ray analyses revealed two encapsulation modes: via -attractive π-π interaction and via- dispersion force depending on the size and shape of the molecule. • In laser desorption ionization, ion peaks derived from the analyte were only detected in the presence of π-π interaction between the analyte and the CS frameworks. • Crystalline sponge laser desorption ionization is promising method to clarify the mechanism of laser desorption ionization using matrix. [ABSTRACT FROM AUTHOR]

Quantum-chemical DFT OPBE/TZVP method with the Gaussian09 program package have been used to calculate bond angles in the macrocycles of 1,8-dioxa-3,6,10,13-tetraazacyclotetradecanetetrathione-4,5,11,12, 1,8-dithia-3,6,10,13-tetraazacyclotetradecanetetrathione-4,5,11,12, and 1,3,5,8,10,12-hexaazacyclotetradecanetetrathione-6,7,13,14 and their complexes with Cr(II), Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) ions with (NNNN) coordination of the donor sites of the ligand forming upon the complexation in the ternary M(II)–ethanedithioamide—formaldehyde and M(II)–ethandithioamide–2-thiapropanediol-1,3 systems and in the quaternary M(II)–ethanedithioamide—formaldehyde—ammonia system in gelatin-immobilized matrix implants. It has been noticed that the macrocycle is considerably distorted in both the macrocyclic compounds (this distortion can be quantitatively characterized by the degree of deviation of the macrocycle from coplanarity) and in their complexes (more than 60°). Depending on the nature of both the M(II) ion and the macrocyclic ligand, this distortion can become weaker or stronger. [ABSTRACT FROM AUTHOR]

The results of quantum-chemical calculations of the molecular structures of d-metal macrocyclic chelate complexes with compartmental and macrocyclic (N,O)- and (N,S) donor atomic ligands arising as a result of “self-assembly” process have been systematized and generalized. It has been noticed that, generally, for such coordination compounds, molecular structures with noncoplanar chelate nodes and noncoplanar macrocycles are more typical than those with coplanar ones. The review covers the works of the author and other researchers carried out mainly over the past 20 years. [ABSTRACT FROM AUTHOR]

Carboxymethyl-substituted and ester-substituted benzo[3]urils have been successfully synthesized and investigated with regard to the supramolecular recognition of inorganic ions by means of fluorescence spectroscopy, 1 H NMR spectrometry, and quantum chemical calculations. The results indicated that benzo[3]uril 4 bearing six carboxyl groups binds to Cu 2+ , Fe 3+ , F − , and CH 3 COO − with strong affinities. Moreover, this macrocyclic host could be used to recognize ion pairs comprising Cu 2+ and CH 3 COO − , Cu 2+ and F − , Fe 3+ and CH 3 COO − , and Fe 3+ and F − through its fluorescence response. In contrast, benzo[3]uril 3 , bearing ester groups, showed only host–guest interactions with Cu 2+ and Fe 3+ . The absence of binding of the macrocycle 3 to anions highlights the important role of the carboxyl groups on benzo[3]uril 4 , which provide active protons to form hydrogen bonds between the host and anion guests. [ABSTRACT FROM AUTHOR]

5-Amino-4,6-dinitro-1,3-dihydroxy-benzene ( 6) was synthesized through the ring-opening reaction of macrocyclic compound 4 with the aid of VNS (vicarious nucleophilic substitution of hydrogen) reaction conditions. The mechanism of ring opening of macrocyclic compound 4 was studied. 5-Amino-2,4,6-trinitro-1,3-dihydroxy-benzene ( 8) was obtained after the nitration of 6 in KNO3 and concentrated sulfuric acid. The thermal stability, sensitivity, and other detonation performances of 6 or 8 were compared to commercially used 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) or 1,3,5-trinitrotriazacyclohexane (RDX), respectively. All target compounds were characterized by using single-crystal X-ray diffraction, NMR spectroscopy, elemental analysis, and differential scanning calorimetry. The sensitivities were determined by using BAM methods (drop-hammer and friction tests). Performance parameters, including heats of formation and detonation properties, were calculated by using Gaussian 03 and EXPLO5 v6.01 programs, respectively. It is worth pointing out that compound 8 has a remarkable measured density of 2.078 g cm−3 at 298 K. In addition, compound 8 is more insensitive than RDX (compound 8: IS=11 J; RDX: IS=7 J; IS is the impact sensitivity). [ABSTRACT FROM AUTHOR]

Purple crystals of the title compound, C 50 H 44 Cl 4 N 4 S 2 were obtained from the reaction of 2,5-bis-(4-propyl-1 H -pyrrol-2-yl)thio-phene and 3,5-di-chloro-benzaldehyde in the presence of tri-fluoro-acetic acid for 3 h and subsequent addition of p -chloranil. The macrocycle in the title compound can be described as a highly planar structure wthe the average deviation of the 32 macrocyclic atoms from the least-squares plane being 0.0416 Å. Its mol-ecular conformation is stabilized by two intra-molecular N-H⋯N bonds and a three-dimensional network is formed by C-H⋯π inter-actions., (© Yoshihiro et al. 2023.)

Macrocyclic compound ( E)-Nidmdbdptaa ( 1) has been synthesized from ( E)-Nidmdptaa, a derivative of macrocyclic ligand tetramethyldibenzotetraaza[14]annulene (tmtaa) and benzoyl chloride by the grafting reaction on 6, 13 positions of ( E)-Nidmdptaa. The demetallation of 1 leads to its free base, ( E)-Hdmdbdptaa ( 2). The monobenzoyl substituted macrocyclic analogues of 1 and 2, ( E)-Nidmmbdptaa ( 3) and ( E)-Hdmmbdptaa ( 4) are also synthesized and characterized, respectively. As well as 2, the introduction of benzoyl groups to nonplanar saddle-shaped ( E)-Nidmdptaa changes the awkward shape of 1, forming a supramolecular host for aromatic ring. The single crystal X-ray diffraction analyses show that 1 includes a benzo ring of the adjacent 1 molecule, and 2 clamps a solvent molecule, toluene, by supramolecular weak interactions of van der Waals forces and crystal close packing. [ABSTRACT FROM AUTHOR]

Nicotinamide adenine dinucleotide kinases (NAD kinases) are essential and ubiquitous enzymes involved in the production of NADP(H) which is an essential cofactor in many metabolic pathways. Targeting NAD kinase (NADK), a rate limiting enzyme of NADP biosynthesis pathway, represents a new promising approach to treat bacterial infections. Previously, we have produced the first NADK inhibitor active against staphylococcal infection. From this linear di-adenosine derivative, namely NKI1, we designed macrocyclic analogues. Here, we describe the synthesis and evaluation of an original series of cyclic diadenosine derivatives as NADK inhibitors of two pathogenic bacteria, Listeria monocytogenes and Staphylococcus aureus. The nature and length of the link between the two adenosine units were examined leading to sub-micromolar inhibitors of NADK1 from L. monocytogenes , including its most potent in vitro inhibitor reported so far (with a 300-fold improvement compared to NKI1). [Display omitted] • A series of original diadenosine-based macrocycles as NADK inhibitor were developed. • Cyclic compounds displayed higher NADK inhibitory potency than acyclic precursors. • Crystal structures explain the affinity gain by intramolecular interactions. • Lm NADK1 inhibition by MC1 represents a 300-fold improvement in comparison to our lead NKI1. • High NADK inhibitory potency of macrocycles was not translated into antibacterial activity. [ABSTRACT FROM AUTHOR]

Membrane-based separation techniques are crucial for mitigating the pollution of aquatic environments and addressing challenges associated with water scarcity. Controlling the structure and chemical functionality of two-dimensional materials can enable the development of new classes of membranes that overcome the limitations of conventional membrane materials to optimize water purification performance. This work uses supramolecular cyclodextrins to decorate the exterior surface of MXene materials, thereby fabricating a series of hybrid membranes via vacuum-assisted self-assembly. These novel nanofiltration membranes can be used to efficiently separate dyes from wastewater. Compared with pristine MXene membranes, the permeability flux of the best-performing membrane increased 23.3 times, while its rejection of methylene blue exceeded 99.7%, most likely because of charge effects and size-selective molecular sieving features of the membranes. This study offers a promising approach for developing advanced membrane separation technologies for water purification by precisely controlling the two-dimensional membrane structure using supramolecular chemistry. This work uses supramolecular cyclodextrins to decorate the exterior surface of MXene (Ti 3 C 2 T x) materials, thereby fabricating a series of hybrid membranes via vacuum-assisted self-assembly. These novel nanofiltration membranes can be used to efficiently separate dyes from wastewater, with good selectivity and stability. [Display omitted] • We prepared a series of hybrid membranes via the combination of MXene and CM-β-CD. • The hybrid membranes exhibited promising rejection effect toward dyes. • The permeability flux of hybrid membranes increased 23.3 times in contrast to that of the pristine MXene membrane. [ABSTRACT FROM AUTHOR]

The review is devoted to the synthesis of thiol-derivatized porphyrins and hybrid nanostructures manufactured from them. Literature data on the main synthetic strategies towards these compounds are summarized, examples of application of thiol-derivatized porphyrins in nanotechnology are given. [ABSTRACT FROM AUTHOR]

Activated perethylated pillar[5]arene crystals show an unexpected alkane-shape- and -length-selective gate-opening behavior. Activated crystals were obtained upon removing solvents from perethylated pillar[5]arene crystals by heating. The activated crystals could quantitatively take up n-alkanes with carbon chains containing more than five carbon atoms as a consequence of their gate-opening pressure. As the chain length of the n-alkanes increased, the gate pressure decreased. A transformation into a herringbone structure was induced when n-hexane was used as a guest. By contrast, cyclic and branched alkanes were not taken up and could not induce a crystal transformation because they were too large to fit in the cavities of the pillar[5]arene. Alkane-shape-selective molecular recognition of pillar[5]arenes in the solution state was translated into the vapor/crystal state. [ABSTRACT FROM AUTHOR]

[Display omitted] • ORR performance of FePc is greatly improved by anion-exchange ionomer in acidic medium. • Anion-exchange ionomer can increase local pH of electrode/electrolyte interface. • The increase in interface pH was verified by in situ Raman technology. Iron–nitrogen doped carbon (Fe/N/C) electrocatalysts are among the most promising materials to replace Pt for the oxygen reduction reaction (ORR). Up to now, most work has been devoted to improving the performance of Fe/N/C catalysts by material design, while ignoring the design of the electrode/electrolyte interface environment. Considering the superior ORR performance of Fe/N/C catalysts in alkaline electrolyte, we attempt to construct a proton-deficient environment at the electrode surface to raise the local pH value. An anion-exchange ionomer with H+ blocking ability was chosen as the binder of the iron phthalocyanine (FePc) catalyst, a model molecule for Fe/N/C. The anion-exchange ionomer can increase the interface pH value as compared with commonly used Nafion binder, which was verified by the electrochemical shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) technique with CO 3 2–/HCO 3 – as a probe. This strategy significantly improves the ORR activity and stability of the FePc catalyst in acidic medium. [ABSTRACT FROM AUTHOR]

The host–guest interactions between phenazine hydrochloride salt (PheH+) and hemicucurbit[n]uril (n = 6 or 12) (HemiQ[6 or 12]) have been studied by1H NMR, UV–vis, IR, mass spectrometry (MS) and quantum chemistry. In1H NMR spectra, the broadening of proton resonances of the hosts suggests the interactions of PheH+with HemiQs. The quantitative stabilities of the host–guest systems have been obtained by UV–vis titration experiments, that is, the stoichiometric interactions of PheH+with HemiQ[6] have been observed with an association constant ofKa = (2.5 ± 1.2) × 106 L mol− 1, while the 2:1 ratio complexes of PheH+with HemiQ[12] are formed with stepwise association constants ofK1 = (9.2 ± 2.8) × 104 L mol− 1andK2 = (6.4 ± 0.9) × 105 L mol− 1, respectively, which induce a total association constant ofKa = 5.9 × 1010 L2 mol− 2. Both the 1:1 and 2:1 complexes have been detected by MS. Quantum chemistry calculations have been used to understand the static structures and thermodynamic stabilities of the supramolecular assemblies. [ABSTRACT FROM AUTHOR]

We present the design and synthesis of polyoxazole-based macrocycles containing a phosphonate group. A reliable route was established that allows for convenient and versatile incorporation of various phosphonate functionalities such as phosphonate ester, acid, and salt at the macrocyclic ring periphery. Such unprecedented macrocyclic compounds are anticipated to be appealing candidates as telomerase inhibitors. [ABSTRACT FROM AUTHOR]

Two new Ag(I) chemically modified carbon paste electrodes were prepared with comparative potentiometric study of 1,3,6,10,13-pentaaza-2,14-(2,6-pyridyl)-cyclotetradecane-4,12-dione (PPCT) and 1,3,6,9,11,12-pentaaza-2,13-(2,6-pyridyle)-bicycle[2,2,9]pentadecane-4,11-dione (PPBP) as ionophore. These sensors have been modified with sol-gel-Au nanoparticles to obtain a wide concentration range for potentiometric determination of Ag(I) in aqueous solutions. The sensors exhibit significantly enhanced selectivity toward Ag(I) ions over a wide concentration range of 4.0 × 10-2.2 × 10 and 2.2 × 10-2.0 × 10 mol L with a lower detection limit of 2.5 × 10 and 2.0 × 10 mol L for PPCT and PPBP modified electrodes respectively. The electrodes are highly selective to Ag(I) ions over a large number of mono, bi, and tri-valent cations. These electrodes were successfully used as indicator electrode for potentiometric determination of silver in sulphadiazine (burning cream) and radiological film. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI) molecular composites were synthesized by chemical oxidative polymerization of the aniline and aniline dimer, N-phenyl-1,4-phenylendiamine, in the presence of a macrocycle, calix[8]arene p-octasulfonic acid (C8S), using ammonium peroxidisulfate as oxidant. The macrocycle has acted both as acid dopant and surfactant to obtain processable PANI-ES. The PANI/calix[8]arene p-octasulfonic acid composite was also obtained by a simple doping of PANI emeraldine base form with calix[8]arene sulfonic acid. The structure of materials was confirmed by Fourier transform infrared, UV-vis and nuclear magnetic resonance spectroscopy. All synthesized composite materials are amorphous and soluble in chloroform, dimethylsulfoxide, NMP, showing excellent solution-processing properties combined with electrical conductivity. Cyclic voltammetry evidenced a good electroactivity for the composite films. Dielectric properties (dielectric constant and dielectric losses) were determined and are comparable with those of other PANI/ionic acid polymer composites. Preliminary studies have evidenced a high dielectric constant (104 at 100 Hz) and electrical conductivity of 6 × 10−3 S/cm for PANI composites. From sulfur elemental analysis of the PANI/calixarene, it results that the content in macrocycle is ∼30% (weight). © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Abstract: Hemicucurbit[6]uril (HemiQ[6])-induced esterification of acids with CH3OH was investigated. Esterification of the model substrate MA in the presence of different amounts of HemiQ[6] had reaction rate constants of k 0.5 =0.18h−1, k 1.0 =0.36h−1 and k 2.0 =0.52h−1. These results confirm that the reaction rate increases with the ratio of catalyst to substrate. Ineffective catalysis of MA esterification with a stoichiometric amount of MeOH suggests that the mechanism for HemiQ[6]-catalyzed esterification is solvolysis. Comparing the HemiQ[6]-catalytic kinetics of MA (4-methoxy-4-oxobut-2-enoic acid) with AA (acrylic acid) and BA (benzoic acid) shows that the catalytic activities should bear relation to the size of substrates. The different conversion of sorts of substrates in the presence of HemiQ[6] reveals that the supramolecular catalysis is favor in the conjugated structures. The inefficacy of HemiQ[12] demonstrates that the catalytic capability depends on the structure of the macrocyclic compound used. [Copyright &y& Elsevier]

Abstract: The template reaction of o-phenylenediamine, 1-benzoylacetone and nickelous acetate tetrahydrate results in two structure isomers, 6,17-dimethyl-8,15-diphenyldibenzo[b,i][1,4,8,11]tetraazacyclotetradecinatonickel (II) (2) and 6,15-dimethyl-8,17-diphenyldibenzo[b,i][1,4,8,11]tetraazacyclotetradecinatonickel (II) (4). However, the latter has been neglected in the previous research because of its low yield in the template reaction. The mechanism of this template reaction is discussed. Though the steric hindrance between the phenyl ring and the benzo ring in 2 is greater than that in 4, the intermediate of the former shows better structural stability than that of the latter, leading to obviously higher final yield of 2 compared with that of 4. n-Butyl alcohol is used artfully to separate the crude product of the template reaction into almost pure 2 and a mixture of 2 and 4 in a mole ratio of 1:5. The free base of 2, 5,14-dihydro-6,17-dimethyl-8,15-diphenyldibenzo[b,i][1,4,8,11]tetraazacyclotetradecine (1), can be synthesized by demetalization of 2 with gaseous HCl. The same treatment to the mixture of 2 and 4 in a mole ratio of 1:5 leads to the free base of 4, 5,14-dihydro-6,15-dimethyl-8,17-diphenyldibenzo[b,i][1,4,8,11]tetraazacyclotetradecine (3). The neglected macrocyclic compounds 3 and 4 have been characterized unambiguously and their single-crystal structures have also been determined by X-ray diffraction analysis for the first time. [Copyright &y& Elsevier]

Abstract: The synthesis and characterization of peripherally tetra-biphenyl-4-yl-methoxy substituted metal-free (4), Ni(II) (5), Cu(II) (6), Zn(II) (7), Co(II) (8) and Pb(II) (9) phthalocyanine derivatives are reported. These new phthalocyanine derivatives show the enhanced solubility in organic solvents and they have been characterized by a combination of IR, 1H NMR, 13C NMR, UV–vis, mass spectral data, elemental analysis and thermal analysis methods (TG/DTA). The photophysical (fluorescence quantum yield and lifetime) and photochemical (singlet oxygen generation and photodegradation quantum yield) properties of tetra-biphenyl-4-yl-methoxy substituted zinc (II) phthalocyanine derivative (7) are also investigated. The fluorescence of this phthalocyanine derivative (7) is effectively quenched by addition of 1,4-benzoquinone (BQ). [Copyright &y& Elsevier]

Abstract: The application of lanthanide complexes in the time-resolved fluorescence imaging of living cells has emerged in the last few decades, providing high-contrast images of cells through detection of the delayed emission. In the present study, we synthesized novel trivalent lanthanide complexes containing the cyclic peptide c(RGDfK) to visualize the αvβ3-integrin-expressing tumor cells. Conjugation of c(RGDfK) with the macrocyclic bipyridine ligand had little effect on the fluorescence properties of the complex, indicating that the coordinated lanthanide ion was well isolated from the peptide. Bright luminescence images of αvβ3-integrin-expressing U87-MG cells were successfully obtained by employing the probes. [Copyright &y& Elsevier]

Two complexes, [Zn2L(µ-OAc)](ClO4) (1) and [Mn2L(OAc)2] · 4H2O (2), were synthesized by [2 + 2] cyclo-condensation between 2,6-diformyl-4-fluorophenol and 1,3-propyldiamine in the presence of metal ions M(II) (M = Zn and Mn), and were characterized by chemical analyses, IR spectra, electrospray mass spectra, and X-ray determinations. The results show that 1 forms dimers through hydrogen bonding. In 2, lattice waters, forming a 1-D water chain, function as glue to form a 3-D supramolecular network through extended hydrogen bonding. pBR322 plasmid DNA can be transformed to nicked form in air by 1 or nicked and linear forms in air by 2. Moreover, their antibacterial activities against S. aureus were investigated using penicillin as reference system. [ABSTRACT FROM AUTHOR]

Abstract: A tetranitrile monomer was synthesized by nucleophilic aromatic substitution of N,N′-(2,2′-(propane-1,3-diylbis(sulfanediyl))bis(ethane-2,1-diyl))bis(4-methylbenzenesulfonamide) onto 4-nitrophthalonitrile. A metal-free phthalocyanine polymer was prepared by the reaction of the tetranitrile monomer under N2 in the presence of 2-(dimethylamino)ethanol at 145 °C for 24 h. Zinc(II), copper(II), cobalt(II), nickel(II), lead(II), phthalocyanine polymers were prepared by reaction of the tetranitrile with the chlorides of zinc (II), copper (II), cobalt (II), nickel (II), lead (II), employing microwave irradiation in the presence 2-(dimethylamino)ethanol at 175 °C, 350 W for 10 min. The thermal stabilities of the phthalocyanine compounds were determined by thermogravimetric analysis. The new compounds were characterized by a combination of IR, 1H NMR, 13C NMR, UV–vis, elemental analysis and MS spectral data. [Copyright &y& Elsevier]

Abstract: Preparation of some novel symmetrically tetrasubstituted metal-free phthalocyanine (6) and metallophthalocyanines (7–10) containing four 18-membered tetrathiadiaza macrocycles moieties on peripheral positions has been achieved by cyclotetramerization reaction of phthalonitrile derivative (5) in a multi-step reaction sequence. Metal-free phthalocyanine (6) was synthesized by microwave irradiation of 13,24-bis[(4-methylphenyl)sulfonyl]-6,7,14,15,23,24-hexahydro-13H,22H-tribenzo[b,h,n][1,4,10,13,7,16]tetrathiadiazacyclo-octadecine-18,19-dicarbonitrile (5) in 2-(dimethylamino)ethanol. The metallophthalocyanines (7–10) were prepared by the reaction of the phthalonitrile compound (5) with NiCl2, Zn(CH3COO)2, CoCl2, CuCl2 salts, respectively, by microwave irradiation in 2-(dimethylamino)ethanol for at 175°C, 350W. The new compounds were characterized by IR, 1H NMR, 13C NMR, UV–Vis, elemental analysis and MS spectra data. [Copyright &y& Elsevier]

Macrocyclic compounds such as metallophthalocyanines demonstrated good catalytic activities toward electrochemical reactions. The characteristics of the central cations in metallophthalocyanines significantly influenced their electrocatalytic activities. Addition of conjugated polymers in electrodes improved the electrocatalytic activity by enhancing the electric conductivity. The electrocatalytic activities of macrocyclic compounds could be further improved by heat treatment. The formation of metallic clusters or metal containing organic fragments after pyrolyzing played an important role in improving electrocatalytic activities of macrocyclic compounds. It was considered that macrocyclic compounds might be functioned as a precursor to obtain well-distributed metallic clusters or metal containing organic fragments. [ABSTRACT FROM AUTHOR]

Abstract: Lewis acid-catalyzed condensation of 1,2- and 1,3-dimethoxybenzenes with paraformaldehyde afforded an ortho-bridged cyclic trimer (1) and a meta-bridged cyclic tetramer (2), respectively. Furthermore, condensation of 1,3,5-trimethoxybenzene with paraformaldehyde in the presence of Lewis acid catalyst successfully rendered the first dodecamethoxy-substituted calix[4]arene (3) with high yield. From X-ray crystallography, it was found that 3 formed the partial cone conformation. The conformational behavior of 3 in the solution was investigated by variable temperature 1H NMR measurements. The partial cone structure observed in the solid state was retained in the solution at low temperatures. Furthermore, because of the slow conformational exchanges of 3 on the NMR time scale, bimodal conformational exchanges were found. The host–guest property of 3 with the electron accepting guest, tetracyanoethylene (TCNE) was examined by UV–Vis measurements, and the ability to associate with the 3-TCNE complex was three times higher than that of the 2-TCNE complex. The observation is due to the superior electron donating property and slow conformational exchanges of 3 compared with those of analogous 2. [Copyright &y& Elsevier]

The novel tetrasubstituted metal-free phthalocyanine and metallophthalocyanines 7, bearing four 13-membered diazadithia macrocycle moieties at peripheral positions were synthesized by cyclotetramerization of the corresponding phthalonitrile derivative in a multi-step reaction sequence. The metal-free phthalocyanine was synthesized by microwave irradiation of the corresponding dicyano compound in 2-(dimethylamino)ethanol for 10min. Metallophthalocyanines were obtained from the respective dicyano derivative and corresponding anhydrous metal salts NiCl2 and ZnCl2, CoCl2, CuCl2, respectively, by microwave irradiation in 2-(dimethylamino)ethanol at 175°C, 350W for 10min. The new compounds were characterized by a combination of IR, 1H NMR, 13C NMR, UV–vis, elemental analysis and MS spectral data. [Copyright &y& Elsevier]

Macrocyclic compounds, such as crown ethers, azacrown ethers, thiacrown ethers, calixarenes and porphyrins, which act as ionophores in lead(II) ion-selective electrodes, are systematically summarized based on the latest literatures. The molecular structure characteristics of the ionophores are generalized. The modification regulations for the substituted ionophores are elaborated with the purpose of improving the response features of the lead(II) ion-selective electrodes assembled by them. It is pointed out that the introduction of pendant moieties which contain soft base coordination centers like N, S and P atoms is in favor of adjusting the cavity size and conformation of the macrocyclic compounds. Furthermore, there is synergic effect between the cavity and the donor sites of the ligand and thus the selective complexation of lead ions is easily realized, resulting in significant avoidance of the interference from other metal ions. The macrocyclic ionophore having the best response characteristics thus far was found to be N,N′-dimethyIcyanodiza-18-crown-6 With the detection limit of 7.0x10-8 (14.5 μg/L), which is one of the uncommon ionophores that can really eliminate the interference from silver and mercury ions. The selectivity coefficients of the ionophore for lead ions over other metal ions, such as alkali, alkaline earth and transition metal ions are in the order of 10-4 or smaller, where the selectivity coefficient of lead(II) over mercury(II) ions is much lower, down to 8.9x10-4. The structure design idea for high-performance ionophore is proposed according to present results. The incorporation of nitrogen atom, especially cyano group or thiocyano group or amino/imino groups, rather than thio atom alone could result in new excellent lead ionophores. The aborative design for metacyclophanes containing aromatic nitrogen atoms with the aim of creating excellent ionophores would also become a potential research trend. The lead(II) ion-selective electrodes have shown widely potential applications in the potentiometric titration, and flow injection potentiometry, and in the direct determination of lead in stack emissions of lead smelters, and assay of lead in rocks, particularly in the direct measurements of trace amount of lead(II) in human hair, blood, edible oil, food, water, and air. [ABSTRACT FROM AUTHOR]

Abstract: A macrocyclic compound obtained from a simple, selective, and effective reaction between N,N-bis(2-hydroxybenzyl)alkylamine derivatives and 1,3-bis(tosyloxy)propane is a good example of a cyclization controlled by synergistic effects of a metal template and hydrogen bonds. [Copyright &y& Elsevier]