Coordination Compounds Research Articles

Dendritic Platinum Nanoparticles Shielded by Pt‐S PEGylation as Intracellular Reactors for Bioorthogonal Uncaging Chemistry

Beyond their classical role as cytotoxics, Platinum (Pt) coordination complexes recently joined the selected group of transition metals capable of performing bioorthogonal reactions in living environments. To minimize their reactivity towards nucleophiles, which limit their catalytic performance, we investigated the use of Pt(0) with different forms, sizes and surface functionalization. We report herein the development of PEGylated Pt nanodendrites with the capacity to activate prodyes and prodrugs in cell culture and in vivo. Their dendritic morphology together with their surface shielding through Pt‐S‐bonded PEGylation synergistically contributed to create catalytic nanoreactors compatible with the highly‐crowded and reductive environment of the cell cytoplasm, thereby facilitating in situ bioorthogonal drug uncaging in cancer cells in 2D and 3D culture, including in microfluidic systems, and xenografted in zebrafish.

Dendritic Platinum Nanoparticles Shielded by Pt‐S PEGylation as Intracellular Reactors for Bioorthogonal Uncaging Chemistry

Beyond their classical role as cytotoxics, Platinum (Pt) coordination complexes recently joined the selected group of transition metals capable of performing bioorthogonal reactions in living environments. To minimize their reactivity towards nucleophiles, which limit their catalytic performance, we investigated the use of Pt(0) with different forms, sizes and surface functionalization. We report herein the development of PEGylated Pt nanodendrites with the capacity to activate prodyes and prodrugs in cell culture and in vivo. Their dendritic morphology together with their surface shielding through Pt‐S‐bonded PEGylation synergistically contributed to create catalytic nanoreactors compatible with the highly‐crowded and reductive environment of the cell cytoplasm, thereby facilitating in situ bioorthogonal drug uncaging in cancer cells in 2D and 3D culture, including in microfluidic systems, and xenografted in zebrafish.

Crystal structures of zinc(II) coordination complexes with isoquinoline N-oxide

The reaction of one equivalent of zinc(II) halide salts with two equivalents of isoquinoline N-oxide (iQNO; C9H7NO) in methanol yields compounds of the general formula [ZnX 2(iQNO)2], with X = Cl− (I), Br− (II) and I− (III). However, starting with zinc(II) perchlorate or nitrate leads to the formation of complex ions with the compositions [Zn(iQNO)6](X)2 for X = ClO4 − (IV), and [Zn(iQNO)(H2O)5](iQNO)2 X 2 for X = NO3 − (V). Complexes (I), (II) and (III), namely dichloridobis(isoquinoline N-oxide-κO)zinc(II) [ZnCl2(C9H7NO)2], dibromidobis(isoquinoline N-oxide-κO)zinc(II) [ZnBr2(C9H7NO)2], and diiodidobis(isoquinoline N-oxide-κO)zinc(II) [ZnI2(C9H7NO)2], each exhibit a distorted tetrahedral coordination geometry around the zinc(II) ion coordinated by two iQNO ligands bound through the oxygen atom and two halide ions. The zinc ion lies on a crystallographic twofold axis in the bromo complex. The X—Zn—X bond angles are approximately 15–17° larger than the O—Zn—O bond angles resulting in the observed tetrahedral distortion. In complex (IV), hexakis(isoquinoline N-oxide-κO)zinc(II) bis(perchlorate), [Zn(C9H7NO)6](ClO4)2, the zinc(II) ion occupies a special position with 3 site symmetry and is octahedrally coordinated by six iQNO ligands, albeit with slight distortions evidenced by a spread of cis bond angles from 85.82 (4) to 94.18 (4)°. The chlorine atom of the perchlorate anion lies on a crystallographic threefold axis. Finally, complex (V) crystallizes with a pseudo-octahedral geometry; pentaaqua(isoquinoline N-oxide-κO)zinc(II) dinitrate–isoquinoline N-oxide (1/2), [Zn(C9H7NO)(H2O)5](NO3)2·2(C9H7NO). The nitrate ions and non-coordinated iQNO molecules engage in π-stacking and hydrogen-bonding interactions with the coordinated water molecules. The iQNO—Zn—O equatorial bond angles range from 88.98 (9) to 94.90 (9)°, with the largest deviation from a perfect octahedral angle attributed to the influence of a weak C—H...O (from water) interaction (2.287 Å) involving the bound iQNO ligand.

Donor/Acceptor Ligands Based on an o-Terphenyl Motif to Achieve Thermally Activated Delayed Fluorescence in Zn(II) Complexes.

The photophysical properties of six new luminescent tetrahedral Zn(II) complexes are presented that survey two electronic donor moieties (phenolate and carbazolate) and three electronic acceptors (pyridine, pyrimidine, and pyrazine). A unique ligand based on an o-terphenyl motif forms an eight-membered chelate, which enhances through-space charge-transfer (CT) interactions by limiting through-bond conjugation between the donor and acceptor. A single isomeric product was obtained in yields up to 90%. Single-crystal X-ray diffraction structures of Zn complexes incorporating either donor show complementary interligand π-π interactions. All of the Zn complexes display long-lived luminescence in the solid state consistent with emission involving the triplet state. The phenolate-based complexes show evidence of CT emission in the solid state only with the strongest (pyrazinyl) acceptor. In contrast, all carbazolate-based complexes show evidence of thermally activated delayed fluorescence (TADF) in the solid and solution state, with photoluminescent quantum yields of up to 39%. These ligands represent a new family of Zn coordination compounds demonstrating TADF/phosphorescent properties that expand upon and elucidate design principles in the pursuit of photoactive earth-abundant metal complexes.

Enhanced Electrocatalytic Hydrogen Peroxide Production via a CuWO4/WO3 Heterojunction with High Selectivity and Stability.

The electrocatalytic conversion of oxygen to hydrogen peroxide offers a promising pathway for sustainable energy production. However, the development of catalysts that are highly active, stable, and cost-effective for hydrogen peroxide synthesis remains a significant challenge. In this study, a novel polyacid-based metal-organic coordination compound (Cu-PW) was synthesized using a hydrothermal approach. Cu-PW served as a precursor to construct a composite electrocatalyst featuring a heterointerface between CuWO4 and WO3 (CuWO4/WO3) through pyrolysis. The CuWO4/WO3 heterojunction exhibits an impressive H2O2 selectivity of 91.84% at 0.5 V, marking a 19.65% improvement compared to the pristine Cu-PW. Furthermore, the CuWO4/WO3 catalyst demonstrates exceptional stability, maintaining continuous operation for 29 h. At 0.1 V, it delivers a hydrogen peroxide yield of 1537.8 mmol g-1 h-1, with a Faraday efficiency (FE) of 85%. Additionally, this catalyst effectively degrades methyl blue, achieving a 95% removal from an aqueous system within 30 min. Theoretical analysis further corroborates the high electroactivity of CuWO4/WO3 heterojunction structure. The Cu-O-W bridge formed during the reaction facilitates interfacial electron transport and enhances the role of the W-O bond in proton adsorption and transfer kinetics. This strong interfacial coupling in CuWO4/WO3 promotes electron transfer and the formation of *OOH intermediates, thereby favoring hydrogen peroxide generation. Hence, the as-prepared CuWO4/WO3 demonstrates great potential as an efficient electrocatalyst for the green synthesis of hydrogen peroxide, exhibiting high efficiency as a two-electron oxygen reduction reaction catalyst. This work offers a new approach for fabricating CuWO4/WO3 electrocatalyst with high electroactivity and selectivity, paving the way for cost-effective and sustainable hydrogen peroxide production, significantly reducing reliance on the conventional anthraquinone process.

Risk assessment and quality management in AIO based on CT-linac for nasopharyngeal carcinoma: An improved FMEA and FTA approach.

All-in-one radiotherapy workflow (AIO) is a novel one-stop solution that integrates the multiple conventional radiotherapy steps from simulation, contouring, planning, image guidance, beam delivery, and in vivo dosimetry into a single device (integrated computed tomography linac, the uRT-linac 506c), making the treatment process more efficient and convenient while reducing errors for cancer patients' initial radiotherapy. Despite its numerous advantages, the implementation of AIO faces challenges such as interdisciplinary coordination, software and hardware complexity, and reliance on artificial intelligence. To ensure its safety and effectiveness, it is necessary to conduct a risk assessment and identify appropriate quality management measures. To perform risk assessment on the AIO for nasopharyngeal carcinoma using failure mode and effects analysis (FMEA) and fault tree analysis (FTA), and to validate the effectiveness of the quality management measures. A flowchart was established for the AIO of nasopharyngeal carcinoma. FMEA analysis was conducted based on the flowchart, and quantitative assessments of each failure mode (FM) were performed to obtain (occurrence), (severity), and (Detectability). Weighted , , and were obtained using the similarity aggregation method (SAM), and the final risk priority number (RPN) was calculated by multiplying these values. The FMs were then evaluated into two groups based on whether quality management (QM) measures were implemented, and sorted by the RPN. Finally, FTA analysis was conducted on the highest-risk FMs identified through ranking. A flowchart of AIO for nasopharyngeal carcinoma was established, consisting of 5 main steps and 28 sub-steps. After FMEA analysis, 86 FMs were identified. In the group without implementing QM measures (QM-free group), the RPN of FMs ranged from 13.5 to 186.2, with a threshold of 94.6 for the top 20% RPN scores, resulting in 17 high-risk FMs. Additionally, 21 FMs had , with a cumulative total of 25 high-risk FMs after removing duplicates. In the group that implemented QM measures (QM group), the RPN of FMs ranged from 3.0 to 46.7, showing an overall decrease compared to the QM-free group. There was a statistically significant difference in RPN between the QM-free (55.80±38.40) and QM (16.17±10.99) groups (p<0.001), validating the effectiveness of the QM measures. Finally, FTA analysis was performed on the highest-risk step identified in the QM-free group with the highest RPN. The improved FMEA and FTA analysis methods are practical and operational, allowing for a comprehensive analysis of potential failures and risks in the AIO for nasopharyngeal carcinoma. They can effectively assist in establishing and evaluating QM standards for AIO of nasopharyngeal carcinoma. Moreover, the analytical methods and QM measures of this study can be effectively applied to AIO for tumors in other sites.

Immobilization of 4-MBA & Cu2+ on Au nanoparticles modified screen-printed electrode for glyphosate detection.

This study introduces an innovative electrochemical biosensor, engineered through the functionalization screen-printed electrode (SPE) with a coordination complex comprised of 4-mercaptobenzoic acid (4-MBA) and copper ions (Cu2+), achieving precise quantitative determination of glyphosate. Electrodepositing gold nanoparticles (AuNPs) onto the electrode surface, forming a self-assembled monolayer (SAM) of 4-MBA via thiol-gold interactions, and immobilizing Cu2+ via coordination bonding with the monolayer, finalizing the electrochemical biosensor construction as Cu2+/4-MBA/AuNPs/SPE. The successful modification of the biosensor interface is confirmed through scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and electrochemical characterization. Through parameter optimization, critical metrics for the biosensor preparation process have been determined. Using square wave voltammetry (SWV), a linear relationship between the glyphosate concentration and the peak current inhibition ratio at the electrode surface is established. Additionally, the repeatability and anti-interference capabilities of the fabricated biosensors are evaluated. The experimental outcomes affirm the biosensor's capability for quantitative glyphosate detection across a 5-100nM range, boasting a 1.65nM limit of detection (LOD). Testing on tap water samples verifies a robust recovery rate for glyphosate residues, spanning 89.84%-107.48%. The proposed biosensor holds significant promise for glyphosate detection, offering substantial applicability and this study provides a valuable reference for the advancement of biosensors geared toward the quantitative assessment of organophosphate pesticides (OPs).

Various Sizes and Shapes of Mixed-Anion Fe(NH2trz)3(BF4)2−x(SiF6)x/2@SiO2 Nanohybrid Particles Undergoing Spin Crossover Just Above Room Temperature

Spin crossover (SCO) iron (II) coordination compounds in the form of nanohybrid SCO@SiO2 particles were prepared using a reverse micelles technique based on the TritonX-100/cyclohexane/water ternary system. Tetraethyl orthosilicate (TEOS) acts as precursor of both the SiF62− counter-anion and SiO2 to obtain Fe(NH2trz)3(BF4)2−x(SiF6)x/2@SiO2 nanoparticles with different sizes and morphologies while modifying the TEOS concentration and reaction time. The adjustable mixed-anion strategy leads to a range of quite scarce abrupt spin crossover behaviors with hysteresis just above room temperature (ca. 293 K), which is very promising for the integration of these materials into functional devices.

Synthesis, structural characterization, and optical properties of two Co(II)-based coordination compounds

Two new Co(II)-based coordination compounds, [Co(Hmctrz)2(H2O)2] (1) and [Co(Hdctrz)(H2O)2]n (2), were synthesized via routine or hydrothermal reactions using cobalt salts, triazole derivatives, and auxiliary reagents. Characterizations, including single-crystal X-ray diffraction, elemental analysis, IR spectroscopy, TGA, and PXRD, confirmed their formation. UV-Vis and fluorescence studies revealed distinct optical properties, with 1 and 2 exhibiting UV absorption peaks at 353 and 370 nm, respectively, and concentration-dependent fluorescence emission, indicating potential for optoelectronic and biological imaging applications. Additionally, adsorption studies showed excellent dye removal capabilities, with 1 achieving 98% removal of methylene blue (MB) and 93% of methyl orange (MO), outperforming 2, which removed 95% of MB and 87% of MO. These results highlight the compounds’ potential in both environmental remediation and advanced material applications.

Apoptotic cell death of stomach cancer lines (AGS) induced by Co-NTB complex through cellular organelles and DNA damage.

Given that stomach cancer is the fourth leading cause of cancer-related death, there is a need to develop new drugs. Among various methods, metal-based coordination compounds are considered as an efficient strategy against this type of cancer. Similarly, the benzimidazole moiety plays a crucial role in biology; thus, various benzimidazole-based compounds have been found to be active as potential anticancer drugs and are currently used in clinical trials. In this study, we explored the benzimidazole-based cobalt(ii) complex as an anticancer agent against AGS stomach cancer cell lines. Interestingly, the MTT assay of the Co-NTB complex shows a lower IC50 value of 4.25 μg mL-1 compared to cisplatin, which has an IC50 of 7.5 μg mL-1 against AGS cell lines. Light microscopy and Hoechst/propidium iodide dye staining clearly indicate that the complex damages DNA, leading to cell death through an apoptotic pathway. The apoptotic cell death pathway was further complemented by Lysotracker and Mitotracker staining, as well as transmission electron microscopy (TEM) imaging. Overall, the Co-NTB complex acts as an effective anticancer agent against AGS stomach cancer cell lines, with apoptotic cell death induced by targeting cellular organelles and DNA.

Manipulating metal-ligand binding in allosteric coordination complexes through ring strain.

The weak-link approach (WLA) to organometallic complexes offers a powerful method to create allosteric shape-shifting coordination complexes. However, chemically tuning the metal-ligand interactions entails challenging syntheses. This study explores the influence of ring strain on the lability of the platinum-sulfur interaction within WLA complexes, providing a simpler alternative to chemical modifications. We study the relationship of ring size, and subsequent reactivity within 4- to 8-membered WLA cyclic Pt coordination complexes through solution and solid-state studies. These results show that strain can direct the energetic preference for the desired allosteric states and therefore, the choice of small molecule effectors required to facilitate such interconversions.

Cure Efficiency and Biocompatibility of an Iron-Based Coordination Complex as a Photoinitiator for Dental 3D-Printed Resins

Objective: The aim of this study was to evaluate the cure efficiency and biocompatibility of a novel iron-based coordination complex used as a photoinitiator in comparison to conventional ethyl (2,4,6-trimethylbenzoyl) phenylphosphinate (TPO-L) and camphorquinone (CQ) as photoinitiators in dental 3D-printed resins. Materials and Methods: Experimental dental resin formulations were prepared by blending 1:1 ratio of Bis-GMA and TEGDMA, to which 0.2 wt% of either the iron-based coordination complex or CQ were added, along with 0.2 wt% EDAB and 0.4 wt% IOD, and the TPO-L. The degree of conversion (DC) was measured using Fourier transform infrared spectroscopy (FTIR). Biocompatibility was assessed by evaluating the viability of L929 fibroblast-like cells using the MTT assay 24 h post-exposure. Statistical analyses included a two-way ANOVA followed by Tukey’s test for post hoc comparisons, with significance at p &lt; 0.05. Results: The degree of conversion for the iron-based coordination complex (84.54% ± 1.69%) was significantly higher than that for the TPO-L (78.77% ± 1.25%) and CQ-based resins (73.21% ± 0.47%) (p &lt; 0.001). The iron-based coordination complex and TPO-L resins exhibited significantly higher conversion than CQ-based resins (p &lt; 0.001). Regarding biocompatibility, the cell viability test revealed that the iron-based coordination complex demonstrated the highest cell viability at 86.5% ± 10.24%, followed by TPO-L with 80.03% ± 11.07%. CQ showed the lowest cell viability of 51.29% ± 8.44% (p &lt; 0.05). Tukey’s test confirmed significant differences between CQ and other photointiators (p &lt; 0.05), while no significant difference was found between TPO-L and the iron-based coordination complex. Conclusions: This study introduces a novel iron-based coordination complex photoinitiator that demonstrates enhanced cure efficiency and comparable biocompatibility to TPO-L, while significantly reducing the cytotoxicity associated with CQ. Its longer absorption wavelength supports deeper layer curing, making it a promising alternative for dental 3D printing, particularly in bioactive scaffold applications requiring minimized cytotoxicity.

Academically based regional quality improvement hubs: Advancing Medicaid's quality strategy in the state of Ohio through state‐academic partnerships

AbstractIntroductionIn 2022, the Ohio Department of Medicaid (ODM) launched a Managed Care Population Health and Quality Strategy to improve healthcare quality and equity for Medicaid Managed Care enrollees. Aligned with national quality objectives, the strategy focuses on personalized care, service coordination for complex needs, reducing health disparities, and includes performance incentives for Managed Care Organizations (MCOs) and innovative provider payment models. While Ohio has made progress in quality improvement, challenges remain in addressing statewide health indicators and disparities and helping healthcare providers adapt to performance‐based models. This report outlines a new approach that builds on Ohio's partnership with six colleges of medicine (CoMs) to support provider organizations and engage stakeholders in quality improvement (QI).MethodsODM established Regional QI Hubs within Ohio's CoMs to advance population health initiatives using the Model for Improvement developed by the Associate in Process Improvement. These academically based hubs collaborate with local healthcare clinics, community partners, and payers on QI projects to enhance care, reduce disparities, and strengthen health systems. By engaging stakeholders in designing and testing change ideas using Plan‐Do‐Study‐Act cycles and electronic health record data feedback, QI Hubs further the goals of the learning health system.ResultsKey lessons highlight the benefits of engaging academic institutions to build internal QI capacity and promote health equity. The model required substantial capacity building and commitment on behalf of academic institutions and strengthening of regional partnerships. Collaboration between MCOs and health clinics is focused on standardizing processes to access services and implement best practices. Patient, family, and community engagement efforts aim to improve patient experience and address drivers of health equity. Each partner leverages resources and benefits from the collaboration.ConclusionsOhio's academically based Regional QI Hub Model offers a promising approach to advancing population health. Policymakers are encouraged to consider integrating academic expertise into state quality strategies.

Leveraging Intramolecular π-Stacking to Access an Exceptionally Long-Lived 3MC Excited State in an Fe(II) Carbene Complex.

The ability to manipulate excited-state decay cascades using molecular structure is essential to the application of abundant-metal photosensitizers and chromophores. Ligand design has yielded some spectacular results elongating charge-transfer excited state lifetimes of Fe(II) coordination complexes, but triplet metal-centered (3MC) excited states─recently demonstrated to be critical to the photoactivity of isoelectronic Co(III) polypyridyls─have to date remained elusive, with temporally isolable examples limited to the picosecond regime. With this report, we show how strong-field donors and intramolecular π-stacking can conspire to stabilize a long-lived 3MC excited state for a remarkable 4.1 ± 0.3 ns in fluid solution at ambient temperature. Analysis of variable-temperature time-resolved absorption data using theoretical models ranging from Arrhenius to semiclassical Marcus theory, combined with computational modeling and X-ray crystallography, reveal a Jahn-Teller stabilized excited state with a high activation barrier for ground-state recovery. The net result is a chromophore with a 3MC excited-state lifetime that is orders of magnitude longer than anything yet observed for an Fe(II) complex.

Selected Metal (Au, Ag, and Cu) Complexes of N-heterocyclic Ligands as Potential Anticancer Agents: A Review.

Nitrogen-based organic heterocyclic compounds are an important source of therapeutic agents. About 75% of drugs approved by the FDA and currently available in the market are N-heterocyclic organic compounds. The N-heterocyclic organic compounds like pyridine, indole, triazoles, triazine, imidazoles, benzimidazoles, quinazolines, pyrazoles, quinolines, pyrimidines, porphyrin, etc. have demonstrated significant biological activities. These heterocyclic organic compounds also coordinate with various metal ions and form coordination compounds. Most of them have shown improved biological activities. The research on the metal complexes of these compounds reported their significant biological activities. N-heterocyclic-based metal complexes showed outstanding anticancer activities against different cancer cell lines, including VEGFR-2, HT-29, MDA-MB-231, MCF-7 K562, A549, HepG2, HL60, A2780, WI-38, Colo-205, PC-3, and other cancer cell lines. Some of these compounds showed better anticancer activity than cisplatin. In this review, we summarized the anticancer properties of N-heterocyclic-based gold (Au), silver (Ag), and copper (Cu) complexes and explored the mechanisms of action and potential structure-activity relationships (SAR) of these complexes. Our goal is to assist researchers in designing highly potent N-heterocyclic-based Au, Ag, and Cu complexes for the potential treatment of various cancers.

SOLID-STATE SPECTROSCOPIC, THERMOKINETICS AND THERMAL ANALYSIS OF ACECLOFENAC COORDINATION COMPLEXES WITH LANTHANUM AND GADOLINIUM

In recent years, the field of coordination chemistry has experienced a surge in interest regarding the synthesis and characterization of coordination complexes for diverse applications. This study is dedicated to investigating coordination compounds resulting from the interaction of nonsteroidal anti-inflammatory drugs (NSAIDs) with metal ions. The study research places significant emphasis on understanding the stability and thermal behavior of these coordination compounds. The utilization of thermoanalytical techniques is crucial in achieving this goal. Thermal analysis and thermokinetics provide valuable insights into the underlying mechanisms, kinetics, and energetics of these reactions, thereby facilitating the optimization of synthesis procedures. The research employs concurrent techniques, namely thermogravimetric analysis (TG) and differential scanning calorimetry (DSC), to explore the thermal stability and decomposition pathways of these coordination compounds. Thermokinetic models and optimization methodologies are subsequently applied to identify key reaction parameters. The primary aim of this research is to unveil the thermal behavior, stability, and reaction kinetics of aceclofenac coordination compounds, thus contributing significantly to the understanding of thermokinetics and thermal analysis in the domain of coordination chemistry. Specifically, this study is focused on aceclofenac coordination complexes involving lanthanum and gadolinium, with the ultimate goal of advancing the field of coordination chemistry.

Synthesis, crystal structure, Hirshfeld surface analysis and DFT calculations of the coordination compound tetra-aqua-bis-{2-[(5-methyl-1,3,4-thia-diazol-2-yl)sulfan-yl]acetato-κO}cobalt(II).

A novel coordination compound, [Co(L)2(H2O)4], was synthesized from aqueous solutions of Co(NO3)2 and the ligand 2-[(5-methyl-1,3,4-thia-diazol-2-yl)sulfan-yl]acetic acid (HL, C5H6N2O2S2). In the monoclinic crystals (space group P21/c), the cobalt(II) ion is located about a centre of symmetry and is octa-hedrally coordinated by two L- anions in a monodentate fashion through carboxyl O atoms and by four water mol-ecules. A relatively strong hydrogen bond between one of the water mol-ecules and the non-coordinating carboxyl-ate O atom consolidates the conformation. In the crystal, inter-molecular hydrogen bonds lead to the formation of a complex tri-periodic structure. Hirshfeld surface analysis revealed that 30.1% of the inter-molecular inter-actions are from H⋯H contacts and 20.8% are from N⋯H/H⋯N contacts. DFT calculations were performed to assess the stability and chemical reactivity of the compound by determining the energy differences between the HOMO and LUMO.

Nano onions based on an amphiphilic Au3(pyrazolate)3 complex.

Multilayer vesicles with an onion-like architecture can form by self-assembly of organic amphiphiles such as dendrimers, small-molecule surfactants, and block copolymers. Thus far, there are limited reports about multilayer vesicles based on coordination compounds. Herein, we show that nano onions are obtained by aggregation of an amphiphilic Au3(pyrazolate)3 complex in aqueous solution. The nanostructures were characterized by cryogenic and transition electron microscopy, dynamic light scattering, and energy-dispersive X-ray analysis. Control experiments with analogous Ag(I) and Cu(I) complexes revealed the importance of Au(I) for the formation of well-defined nano onions. A structurally related Au(I) complex without solubilizing polyethylene glycol side chains was analyzed by single-crystal X-ray diffraction. In the solid state, columns of offset, π-stacked Au3(pyrazolate)3 complexes are observed, but short intermolecular Au⋯Au contacts were not found. Molecular dynamics simulations provided further insights into the aggregation process in aqueous solution, supporting the formation of nano-onion structures through lateral interactions between stacked complexes.

Versatile copper(ii) discrete and polymeric coordination compounds with (pyridine-2-yl)methylenenicotinohydrazide and azelaic acid

This manuscript presents the synthesis, structural characterization and DFT analysis of a series of copper(ii) coordination compounds synthesized through various methods.

Anticancer potential of copper(i) complexes based on isopropyl ester derivatives of bis(pyrazol-1-yl)acetate ligands.

In this paper, the isopropyl ester derivatives LOiPr and L2OiPr of bis(pyrazol-1-yl)acetic acid and bis(3,5-dimethyl-pyrazol-1-yl)acetic acid were used as chelators for the preparation of new Cu(i) phosphane complexes 1-4. They were synthesized by the reaction of [Cu(CH3CN)4]PF6 and triphenylphosphine or 1,3,5-triaza-7-phosphaadamantane with LOiPr and L2OiPr ligands, in acetonitrile or acetonitrile/methanol solution. The authenticity of the compounds was confirmed by CHN analysis, 1H-, 13C- and 31P-NMR, FT-IR spectroscopy, and electrospray ionization mass spectrometry (ESI-MS). Furthermore, the electronic and molecular structures of the selected Cu(i) coordination compound 3 were investigated by synchrotron radiation-induced X-ray photoelectron spectroscopy (SR-XPS), and the local structure around the copper ion site was studied combining X-ray absorption fine structure (XAFS) spectroscopy techniques and DFT modelling. Triphenylphosphine as a coligand confers to [Cu(LOiPr)(PPh3)]PF6 (1) and [Cu(L2OiPr)(PPh3)]PF6 (3) a significant antitumor activity in 3D spheroidal models of human colon cancer cells. Investigations focused on the mechanism of action evidenced protein disulfide-isomerase (PDI) as an innovative molecular target for this class of phosphane copper(i) complexes. By hampering PDI activity, copper(i) complexes were able to cause an imbalance in cancer cell redox homeostasis thus leading to cancer cell death - a non-apoptotic programmed cell death.