Journal of Inclusion Phenomena and Macrocyclic Chemistry最新文献

The reaction of a square-planar platinum(II) complex containing two bis(2-diphenylphosphinoethyl)phenylphosphine (triphos), [Pt(triphos)₂](NO₃)₂, with [Au(tu)₂]Cl (tu = thiourea) gave a new trinuclear Au^I₂Pt^II complex, [Pt(triphos)₂{Au(tu)}₂]Cl₂(NO₃)₂, through Au-P coordination. While the [Pt(triphos)₂]²⁺ unit in [Pt(triphos)₂](NO₃)₂ adopted the trans-meso configuration, only the cis-racemic isomer was observed for [Pt(triphos)₂{Au(tu)}₂]Cl₂(NO₃)₂. ³¹P NMR spectroscopy indicated rapid equilibrium among the possible isomers of [Pt(triphos)₂]²⁺, which facilitated the trans-to-cis transformation at the Pt^II center in this system. Additionally, we observed that this structural transformation led to an increase in the emission intensity.

To improve the efficiency of cyclodextrins as carotenoid carriers, the kinetics and thermodynamics of the inclusion complex formation between modified β-cyclodextrin (βCD-NH₂) and β-carotene (βCT) were studied using surface plasmon resonance (SPR) at pH 7.4 and theoretical calculations. The observed dissociation rate of the [βCD-NH₂/βCT]° inclusion complex is small ((2.59times 1{0}^{-1} {text{s}}^{-1})), indicating that βCD-NH₂ only interacted with the βCT ionone group to form inclusion complex. The βCD-NH₂/βCT binding constant is (2.80times 1{0}^{4} text{L} {text{m}text{o}text{l}}^{-1}) (at 298.15 K), and its temperature dependence indicates that the [βCD-NH₂/βCT]° formation is driven by hydrophobic interactions (({Delta }H^circ = 28.83 text{k}text{J} text{m}text{o}{text{l}}^{-1}) and (T{Delta }S^circ = 54.21 text{k}text{J} text{m}text{o}{text{l}}^{-1})) caused mainly by the βCT end group desolvation. In contrast, the formation of the [βCD-NH₂/βCT]^‡ activated complex via association between free molecules and dissociation of [βCD-NH₂/βCT]° occurred with the overcoming of an energy barrier ((E_{a}^{ddag } = 40.77~{text{kJ mol}}^{{ - 1}} ~) and ({E}_{d}^{ddag}=11.94 text{k}text{J} text{m}text{o}{text{l}}^{-1})) and decrease in entropy ((T{varDelta S}_{a}^{ddag}=-11.70 text{k}text{J} text{m}text{o}{text{l}}^{-1}) and (T{varDelta S}_{d}^{ddag}=- 65.92 text{k}text{J} text{m}text{o}{text{l}}^{-1})).

Bone adhesives are known as a promising fracture treatment material because they can quickly heal broken bones. However, the existing bone adhesives have the disadvantages of weak binding ability to bone tissue, non-absorption, or difficulty in curing under wet conditions, which limits their wide application in the field of bone tissue engineering. In this study, the raw material of magnesium phosphate bone adhesive was modified, and the composite material of magnesium phosphate bone repair was prepared by the method of solid–liquid blending crosslinking. Mineral-organic composite, a new type of bone adhesive was prepared using calcined dolomite and montmorillonite as mineral components, phytic acid and gelatin as organic components. The compressive strength, porosity and bonding strength of the magnesium phosphate-based bone adhesive were analyzed by Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy. When the dosage of dolomite is 8 wt% and the concentration of gelatin is 9 wt%, the adhesion strength of the bone adhesive is 2.04 MPa after 168 h placement. And the compressive strength of the bone adhesive was 6.66 MPa after 168 h placement. After the prepared bone adhesives were immersed in SBF solution for 14 and 21 days, EDS analysis showed that the accumulated material was bone-like hydroxyapatite, indicating that the prepared bone adhesives had good osteogenic activity. In addition, it was also found that the bone adhesive had fluid absorption ability and no cytotoxicity. So, conclusively it can be stated that such newly synthesized bone adhesive has significant medical potential.

In the present work, host compounds trans-9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboxylate (H1), trans-α,α,α’,α’-tetraphenyl-9,10-dihydro-9,10-ethanoanthracene-11,12-dimethanol (H2) and trans-α,α,α’,α’-tetra(p-chlorophenyl)-9,10-dihydro-9,10-ethanoanthracene-11,12-dimethanol (H3) were assessed for their host ability for anisole (ANI) and 2-, 3- and 4-bromoanisole (2-, 3- and 4-BA). It was demonstrated that H3 formed complexes with each of these guest species, while H1 and H2 only possessed the ability to enclathrate ANI. When H3 was crystallized from equimolar binary guest solutions, a significantly enhanced host affinity was observed for ANI and 3-BA. As examples, equimolar binary ANI/2-BA and 2-BA/3-BA solutions afforded complexes that demonstrated a near-complete H3 selectivity towards ANI (97.5%) and 3-BA (94.5%), respectively. Furthermore, from H3 crystallization experiments in binary ANI/2-BA, ANI/4-BA, 3-BA/2-BA and 3-BA/4-BA mixtures, where the molar guest amounts were varied sequentially, were calculated significant selectivity coefficients (K values), so much so that H3 may be used to separate very many of the guest anisole mixtures prepared in this work, through supramolecular chemistry strategies, which serves as a greener separation protocol compared with tedious and energy intensive fractional distillations. Thermal analyses were also used to investigate the relative stabilities of each of the single solvent complexes.

Functional dyes can interconvert energies, such as light, heat, and electricity, and they have broad applications in various fields. This review highlights our endeavors in the creation of novel photofunctional materials in solution and solid states via molecular assemblies, linkage, and distortion and the integration of supramolecular complex formation and host–guest chemistry. One approach involves the synthesis of solid-state luminescent materials with the use of cocrystals comprising host molecules with dye backbones and guest molecules derived from aromatic compounds. Cocrystal formation is tuned via intermolecular interactions, such as hydrogen bonding, charge-transfer interactions, π-π stacking, and inclusion phenomena of the crystal engineering approach. This state leads to the emergence of properties such as fluorescence, room-temperature phosphorescence, and the potential for applications in optical sensors. In the second approach, functional dyes comprising multidentate ligands with various elements, which results in photofunctional properties in solution and solid states. This method delves into structural characteristics affected by the distortion and torsional angles of multinuclear complexes and their resulting photophysical properties. Multinuclear complexes encompass helical and axial chirality. Here, we discuss the isolation of enantiomers through optical resolution and their subsequent circular dichroism and circularly polarized luminescence characteristics. The position and nature of substituents considerably affected the ground and excited states of the complexes, which led to the formation of unique photofunctional materials. These methodologies offer insightful and effective avenues for the further improvement of the functionality and device applicability of functional dyes.

The interaction between ciprofol and human serum albumin (HSA) was studied using spectroscopy-based approaches at different temperatures under simulated physiological conditions in vitro. Quenching of intrinsic Trp fluorescence of HSA with increasing ciprofol concentration is the actuating tool in the analysis. Experimental results proved that ciprofol quenched the intrinsic fluorescence of HSA through a static quenching mechanism. The thermodynamic parameters (ΔG = -2.35 × 10⁴ J·mol⁻¹, ΔS = -131 J·mol⁻¹·K⁻¹, and ΔH = -6.39 × 10⁴ J·mol⁻¹ at 310 K), binding sites (n = 0.83), and binding constant (K_A = 9.12 × 10³ M⁻¹) indicated that hydrogen bond and van der Waals forces played a major role in the HSA-ciprofol association with weak binding force. Furthermore, the circular dichroism, synchronous, and three-dimensional fluorescence spectral results indicated adaptive structural changes of HSA in the presence of ciprofol. In addition, the effect of some common metal ions on the binding between ciprofol and HSA was examined, and Fe³⁺ and Hg²⁺ were proven to help prolong the storage time and improve the drug efficacy. The study provides accurate and full basic data for clarifying the binding mechanisms of ciprofol with HSA and helps understand its effect on protein function during the blood transportation process and activity in vivo.

Trialkyl-monoacetic acid derivatives of p–t-octylcalix[4]arene and calix[4]arene were prepared to investigate the effect of the alkyl branches attached to the phenoxy oxygen atoms and the p-position on the selective extraction of Li⁺ over Na⁺. Alkyl branches on the phenoxy oxygen atoms remarkably affected the Li⁺ selectivity, whereas those at the p-position had less effect. The former can contribute to excluding Na⁺ extraction while enabling Li⁺ extraction. Optimal selection of the alkyl branch improves the Li⁺ selectivity of calix[4]arene. However, sterically-hindered p–t-octylcalix[4]arene with three 2-ethylbutyl branches exhibited opposite selectivity.

Chelation and solution thermodynamic stability of a tripodal hydroxypyranone-based chelator (tris[(5-hydroxy-4-oxo-pyran-2-yl)methyl]benzene-1,3,5-tricarboxylate), TBHPY, towards biologically relevant divalent metal ions:Cu(II), Fe(II), Ni(II), Co(II) and Zn(II) were studied by potentiometric and spectroscopic methods in 9:1 (H₂O:DMSO) medium. The metal ions formed ML, MLH_2, MLH, MLH_-2, and MLH_-1 type complexes with high formation constants. The ligand was explored for its application as a potential fluorimetric sensor and examined in the presence of various cations. Nearly twofold quenching was observed upon addition of Gd(III) to TBHPY. The experimental, spectroscopic and thermodynamic stability results were validated with the theoretical quantum mechanical calculations using density functional theory (DFT). The geometrical structures, electronic properties,and bonding behavior of the complexes are described in detail.

The zwitterionic dicarboxylate 1,1′-[(2,3,5,6-tetramethylbenzene-1,4-diyl)bis(methylene)]bis(pyridin-1-ium-4-carboxylate) (L) has been reacted with uranyl nitrate under solvo-hydrothermal conditions and in the presence of KReO₄ to give the complex [UO₂(L)(OH)(H₂O)](ReO₄) (1). This compound crystallizes as a cationic, monoperiodic coordination polymer with ReO₄^– as a simple counterion. The daisy-chain polymer is based on dinuclear rings built by the convergent zwitterionic ligands, these rings being linked to one another by double hydroxide bridges. In addition to a Coulombic interaction with a pyridinium ring, ReO₄^– is involved in one OH(water)⋅⋅⋅O and four CH⋅⋅⋅O interactions, and it is thus nestled in a cavity formed by three chains, seemingly with some selectivity over nitrate and chloride anions also present in the reaction mixture. This result illustrates the interest of zwitterionic dicarboxylates in building cationic assemblies able to trap ReO₄^–, a surrogate for the radioactive TcO₄^–, an anion of environmental relevance.

Graphical abstract

A zwitterionic dicarboxylate ligand was reacted with the uranyl ion to generate a cationic, daisychain coordination polymer including perrhenate as counterion. Examination of the Hirshfeld surface of the anion allows for an analysis of the weak interactions involved.