Journal of Inclusion Phenomena and Macrocyclic Chemistry最新文献

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.

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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.

Two new lanthanide complexes with the general formula [Ln(hqtsc)₂Cl], where Ln = Eu³⁺/Tb³⁺ and hqtsc is (E)-2-((8-hydroxyquinolin-2-yl)methylene)hydrazine-1-carbothioamide have been synthesized. The structures of the complexes have been elucidated through IR, ¹H NMR, ¹³C NMR and HR-mass spectroscopy. The coordination behavior of the ligand was investigated with proton and two trivalent lanthanides, Eu(III) and Tb(III), by potentiometric and spectrophotometric methods in a highly aqueous medium. The studies reveal that the two lanthanides form complexes of the type ML₂H₂, ML₂H₁, ML₂, ML₂H_−1, and ML₂H₋₂. The high formation constants of ML with log β = 26.55 and 27.13 indicate that these complexes will become promising candidates for chelation therapy, radioimmunotherapy, and other biomedical applications. Further, the change in colour and electronic spectra of the complexes in the presence of anions showed the selective colorimetric sensing ability towards H₂PO₄⁻ (orange/yellow→, colorless) and CN⁻ (orange/yellow → red). The DFT studies were also carried out to establish the structure, bonding, and sensing mechanism of the complexes.

The objective of this study is to examine the determinants influencing the efficacy of intravesical administration of botulinum toxin A (BoNT-A) in patients suffering from overactive bladder (OAB). The study included 32 females diagnosed with OAB, with or without urge urinary incontinence. All participants underwent BoNT-A injections (100 units) at the posterior bladder wall (20 points) from our institution between March 2017 and June 2020. Clinical data was gathered, and the severity of OAB was evaluated both before and four weeks following the procedure utilizing the International Consultation on Incontinence Modular Questionnaire-Urinary Incontinence (ICIG-UI) and the Overactive Bladder Symptom Score (OABSS). The study also looked into the status of medication for OAB four weeks after the procedure. Total mean ICIQ-UI and OABSS were significantly improved four weeks after BoNT-A injection (14.00 ± 3.46 to 7.00 ± 6.82, p < 0.001 and 11.40 ± 5.01 to 6.40 ± 1.25, p = 0.009, respectively). Younger age, longer OAB duration, and ongoing OAB medication were the factors that significantly improved the effectiveness of BoNT-A injection.

The objective of this investigation is to ascertain the determinants associated with the amelioration of symptoms in female patients suffering from overactive bladder (OAB) following treatment with 0.2 mg of imidafenacin. The study included 66 female OAB patients who had been prescribed a daily dose of 0.2 mg imidafenacin for a minimum of 3 months, spanning from March 2018 to June 2020. Various clinical parameters including age, coexistence of additional voiding symptoms, prior history of urological surgeries, and responses to the Overactive Bladder Symptom Score questionnaire (OABSS), both pre- and post-initiation of imidafenacin therapy, were evaluated. The mean total OABSS scores recorded before and 3 months subsequent to imidafenacin therapy were 8.36 ± 3.65 and 5.15 ± 3.22, respectively. Following the 3-month course of imidafenacin treatment, there was a statistically significant improvement in both the total OABSS score and the severity of OAB symptoms (p < 0.001 for both). Prior to treatment initiation, Group B (n = 38) exhibited significantly higher total OABSS scores and subscores compared to Group A (n = 28) (p < 0.05). Multivariable analysis identified the OABSS subscores for items 1 and 3 prior to treatment as significant predictors for the improvement of OAB severity subsequent to imidafenacin therapy (p = 0.046, OR 3.10, 95% CI 1.019–9.440 and p < 0.001, OR 2.77, 95% CI 1.671–4.587, respectively). Consequently, imidafenacin emerges as an efficacious therapeutic agent for alleviating OAB severity in female patients, with the OABSS subscores for items 1 and 3 prior to treatment initiation holding potential utility in predicting the efficacy of imidafenacin in managing OAB.

Utilizing a high-dilution condition method, a new aza-oxo macrocycle, referred to as L, was synthesized as a chemosensor. The chemosensing capabilities of L were thoroughly investigated using fluorescence studies. The obtained results demonstrate that L effectively responds to the presence of zinc ions, leading to a significant increase in fluorescence intensity. Comparative studies were conducted to investigate the impact of various metal cations, including Cr(III), Mn(II), Fe(II), Fe(III), Co(II), Ni(II), Cu(I), Cu(II), Zn(II), Cd(II), Gd(III), Na(I), K(I), Ba(II), Mg(II), Al(III), Pb(II), Sn(II), Hg(II), and Ag(I), on the fluorescence of L in an aqueous ethanol environment. During our investigations, a binding constant value of 7.81 × 105 M⁻¹, with a 1:1 stoichiometry for Zn²⁺–L interactions, was established. Additionally, a low detection limit of 2.51 × 10⁻⁸ M and a rapid response time were observed. Furthermore, the chemical inputs of Zn²⁺ and Cu²⁺ ions meet the conditions of an INHIBIT molecular logic gate.

Cyclosporine A (CP) inclusion complex using cyclodextrin (binary) and cyclodextrin with TPGS (ternary) was prepared by the freeze-drying method. The phase solubility study was performed to calculate the solubility parameters. The prepared formulations were evaluated for saturation solubility and drug release studies. The spectroscopy and molecular docking studies were performed to confirm the formation of inclusion complex. The phase solubility results revealed a high stability constant for both binary and ternary samples. A significant enhancement in saturation solubility and dissolution was found in the prepared inclusion complexes. The spectroscopy studies revealed no interaction between the drug and carrier. The molecular docking study displayed the formation of a stable complex with a good docking score. The diffraction pattern showed the conversion of crystalline CP into an amorphous form after the formation of the inclusion complex. The findings were also supported by the saturation solubility study, which showed a significant enhancement in solubility. From the results, it can be concluded that Cyclosporine A inclusion complex using HP βCD with TPGS is an excellent delivery system. Therefore, the prepared delivery systems may be an alternative to the conventional delivery system for enhanced solubility of highly lipophilic drugs.

Three new dinuclear triple helicates were synthesised using a ditopic semi-rigid pyridylylimine ligand L, separated by a diphenoxy-biphenol spacer providing considerable length to the backbone. L and the new large dinuclear triple helicate complexes [Fe₂L₃](BF₄)₄ (1), [Ni₂L₃](BF₄)₄ (2) and [Zn₂L₃](BF₄)₄ (3) have been characterised in solution and solid state. Single crystal X-ray diffraction was used to investigate overall complex ion shape as the coordination sphere was modulated by metal ion selection. Small differences in complex shape were seen to arise due to subtle distortions in coordination sphere environments. This study sheds light on how the length and twist of dinuclear triple helicates can be tuned by selection of coordinating metal ion.

We have developed a chemosensor using calix[4]arene, which features a thiosemicarbazone binding/sensing unit and a naphthalene chromogenic group. Our objective was to understand the intricate binding affinity of these chemosensors towards a diverse range of anions and cations using UV–Visible, HNMR and IR spectroscopic techniques. We showed that this chemosensor can form complexes with Ag(I) or Cu (II) and to detect CN⁻ or F⁻ ions by deprotonation of thiosemicarbazone. To understand the behavior of these interactions, our analysis provides information on the interaction patterns between the receptors and the ions. The sulfur and imine nitrogen on the thiosemicarbazone substituent are vital sites of engagement for cation ions, as evidenced by the observed changes in IR. HNMR studies for interaction with anions indicate the involvement of the thiosemicarbazone hydrogens. Interactions taking place during complex formation with cations lead to changes in the color of the solution or solid complex, easy to follow by UV–Vis spectrocopy. Our study improves the understanding of molecular recognition of this chemosensor, highlighting its potential for ion- selective detection.

The inclusion of 1,8-octanediphosphonic acid (OA) in cucurbit[7]uril (Q[7]) has been investigated via a combined solid state and solution study. The reaction of OA and Q[7] in water led to the formation of a 1:1 inclusion compound 1 as a white crystalline material. Synchrotron single crystal X-ray diffraction revealed its detailed structure validated by Raman spectroscopy with featured vibrational modes from both organic molecules. Subsequent ¹H solution NMR data supported the formation of a 1:1 inclusion complex in aqueous solution. The changes in NMR chemical shifts are consistent with the solid-state orientation in which the phosphonic acid groups of OA are oriented externally to the carbonyl portals and the intervening alkyl chain lies within the cavity of Q[7]. However, the solution study also inferred possible formations of other complexes in solution. This work highlighted the advantage of combining solid state and solution studies to reveal the detailed molecular interactions involving complex inclusion phenomena.

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