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Postoperative C5 palsy is a debilitating complication of cervical spine surgery with unclear etiology. A previous study of 12 patients proposed a three-variable model to predict postoperative C5 palsy based on MRI measurements of the anteroposterior diameter of the spinal canal (APD), foraminal diameter (FD), and cord-lamina angle (CLA). The initial paper reported an area under the receiver operating characteristic (ROC) curve (AUC) of 0.97, with a sensitivity of 91% and specificity of 100%. This study aimed to validate the three-variable model and its individual components in a larger patient cohort. Adult patients who underwent anterior or posterior cervical discectomy and fusion at C4-5 with subsequent C5 palsy were retrospectively identified (2010-2023). Postoperative C5 palsy was defined as a new or increased deltoid/biceps weakness on manual motor testing. Patients with C5 palsy were propensity score-matched 1 to 3 to a control group based on age, sex, Charlson Comorbidity Index score, procedure type, and levels fused. A biostatistician used the APD, FD, and CLA MRI measurements to calculate ROC curves, sensitivities, and specificities for single- and three-variable predictive models of postoperative C5 palsy. A total of 42 patients with C5 palsy were matched to 126 controls. There were no significant differences in preoperative APD (mean 9.20 vs 9.45 mm, p = 0.426), minimum FD (mean 1.82 vs 1.90 mm, p = 0.609), or maximum CLA (mean 38.8° vs 38.5°, p = 0.867) between the C5 palsy and control groups. The APD had an AUC of 0.455, sensitivity of 0.912, and specificity of 0.148. The minimum FD had an AUC of 0.501, sensitivity of 0.765, and specificity of 0.330. The maximum CLA had an AUC of 0.513, sensitivity of 0.765, and specificity of 0.348. When applied collectively, the three-variable predictive model performed similarly to chance, yielding an AUC of 0.519 (95% CI 0.410-0.628), sensitivity of 0.676, and specificity of 0.452. In a large, well-matched validation cohort, the preoperative MRI parameters of the APD, FD, and CLA were not predictive of postoperative C5 palsy, both individually and as a three-variable model. The etiology of C5 palsy remains poorly understood and reliable preoperative predictors have yet to be identified. The previously proposed three-variable model demonstrated inconsistent predictive utility for postoperative C5 palsy, and the model should be interpreted with caution before more rigorous external validation.

The oxygen-bridged frustrated Lewis pair (FLP) Bis2Ga-O-PtBu2 (Bis = CH(SiMe3)2; GaOP) is capable of activating and further transforming multiple nitrogen-containing substrates. Remarkably, the reaction with pyridazine leads to an instantaneous, atom-economical ring-contraction at ambient temperature, producing the GaOP·3-hydro-2-imino-pyrrole adduct. Further rearrangement to the GaOP·2-amino-pyrrole adduct occurs due to an imine-enamine tautomerism. Heating this mixture to 70 °C yields the GaOP·5-hydro-2-imino-pyrrole adduct via a 1,3-hydrogen shift. Using phthalazine instead results in the formation of a stable 1,2-addition product across the N-C bond, whereas a subsequent ring-contraction is thermally inducible, yielding the GaOP·9-hydro-2-imino-isoindole adduct. For cis-azobenzene, a 1,2-addition to both nitrogen atoms is observed, while tests for 1,2,4,5-tetrazine derivatives and compounds with N-N single bonds, including hydrazines, show different types of decomposition. Strikingly, ring-opening of the three-membered, N-containing ring in p-tosylaziridine is demonstrated, where by a six-membered ring is formed, as it is the case for the capture of N-sulfinylaniline.

Early identification of abnormal levels of uric acid (UA), xanthine (XA), and hypoxanthine (HXA) in body fluids and food could assist in the prevention of various diseases. Additionally, one of the antibiotics, chloramphenicol (CAP), when used excessively, can cause harmful side effects on human/animal health and ecological risks. Therefore, the accurate detection of these substances is of great significance. Herein, the V(IV) species and amino-functionalized terephthalic acid were selected to prepare a series of multivariate heterometallic-organic frameworks, MIL-125(Ti-V)-xNH2 (x = 0, 25%, 50%, 75%, and 100%), which was established as an electrochemical sensing platform for detecting small organic molecules. Integrating electrocatalytically active vanadium centers and polar amino groups within the cavity of parent MIL-125(Ti) regulates the electrocatalytic activity and selectivity toward electrochemical detection. Under optimal conditions, MIL-125(Ti-V)-100%NH2 exhibited a linear detection range of 2 to 150 µM for simultaneous detection of UA, XA, and HXA with detection limits of 0.520, 0.502 and 0.620 μM (S/N = 3), respectively. In addition, MIL-125(Ti-V)-100%NH2 exhibited the best performance for CAP detection with an outstanding wide linear response range (1 to 310 µM) and a low limit of detection (0.0020 μM, S/N = 3). Owing to the wide linear range, low detection limit, high selectivity, and excellent stability, MIL-125(Ti-V)-100%NH2 provided an ideal platform for real sample analyses.

Polyoxovanadate-alkoxides are a class of polynuclear earth-abundant transition metal compounds with highly tunable catalytic, redox, and magnetic properties. These species are ideal electroactive molecular agents for environmentally friendly energy storage applications, such as non-aqueous redox flow batteries. As such, it is fundamental to understand structure-redox relationships in the multielectron redox profiles of polyoxovanadate-alkoxides species. Here, we studied the redox properties of monomeric vanadate-alkoxide species that control the formation of two distinct chemical spaces with mix-valent clusters and fully reduced cyclic species. The accuracy of various density functional theory approximations and basis sets choices was benchmarked against domain-based local pair natural orbital coupled cluster, specifically DLPNO-CCSD(T). To further confirm the broader applicability of density functional theory in higher nuclearity species, we studied the redox profile of [(VV6-nVIVnO6)(O)(OCH3)12]4-n, [(Nb = O)(VV5-nVIVnO5)(O)(OCH3)12]4-n, [(M-OCH3)(VV5-nVIVnO5)(O)(OCH3)12]4-n (M = Ti, Zr, or Hf), and [(Fe-Cl)(VV5-nVIVnO5)(O)(OCH3)12]3-n hexanuclear polyoxovanadate-alkoxide species. The calculated redox profiles of these species were in good agreement with experimental data with an average absolute error of 0.11 V.

While the reactivity profiles of rare earth bis(trimethylsilyl)amides (N″ = {N(SiMe3)2}-) are well-understood, there have been few reactivity studies of rare earth bis(trimethylsilyl)phosphide (P″ = {P(SiMe3)2}-) complexes. Here we report reactions of the dimeric solvent-free yttrium phosphide complex [Y(P″)2(μ-P″)]2 (1-Y) towards a selected range of heteroallenes and nitriles. Treatment of 1-Y with N,N'-dicyclohexylcarbodiimide gives the homoleptic monomeric yttrium phosphaguanidinate complex [Y{(NCy)2CP″-κ2-N,N'}3] (2-Y), whereas reaction of 1-Y with cyclohexylisocyanate gives the heteroleptic dimeric yttrium phosphaureate siloxide complex [Y{OC(NCy)(P″)-κ2-N,O}2(µ-OSiMe3)]2 (3-Y). Conversely, 1-Y reacts with ethyl- or cyclohexyl-isothiocyanate to give the heteroleptic dimeric yttrium phosphathioureate phosphide complex [Y{SC(NEt)(P″)-κ2-N,S}2(µ-P″)]2 (4-Y) and homoleptic monomeric yttrium phosphathioureate complex [Y{SC(NCy)CP″-κ2-S,N}3] (5-Y), respectively. By contrast, 1-Y reacts with adamantyl- and tert-butyl-nitrile to give the respective yttrium phosphide solvated adducts fac-[Y(P″)3(NCAd)3] (6-Y) and [Y(P″)3(NCtBu)2] (7-Y), with no observed migratory insertion into Y-P bonds. All products were characterised by multinuclear NMR and ATR-IR spectroscopy, single crystal X-ray diffraction, and elemental analysis. Together, this work shows the strong dependence of the reactivity of rare earth phosphide complexes on substrate donor atom identity and steric profile, giving rise to both migratory insertion and ligand rearrangement pathways.

The overuse and improper disposal of important chemicals such as biomolecules, antibiotics, and pesticides have become serious global problems, creating an urgent need for simple and effective methods to remove them quickly from the environment. To address this issue, two mixed-ligand Cd(II) coordination polymers (CPs), {[Cd(H3L)(bb)2]n} (1) and {[Cd5(L)2(Bid)3(H2O)4]·4H2O}n (2), incorporating the multicarboxylate ligand H5L (H5L = 3,5-di(2',4'-dicarboxylphenyl)benzoic acid) and the N-donor linkers bb (bb = 4-(1H-imidazol-1-yl)-4'-bromo-biphenyl) and Bid (Bid = 1,4-bis(1-imidazolyl)-2,5-dimethylbenzene), were constructed under solvothermal conditions. Detailed structural and physicochemical characterization was carried out using FT-IR, PXRD, TGA, UV-vis spectroscopy, and single-crystal X-ray diffraction. CP 1 demonstrates excellent photocatalytic activity toward the UV-induced degradation of the antibiotic metronidazole (MDZ), achieving 95.32% degradation within 60 min. Radical-trapping experiments confirm that superoxide radicals (˙O2-) are the predominant reactive species involved in the degradation mechanism. Overall, these results suggest that structurally adaptable Cd(II) coordination polymers are promising photocatalysts for the removal of emerging pharmaceutical pollutants from aqueous environments.

Photocatalytic hydrogen evolution (PHE) from water splitting represents a promising route for sustainable energy conversion, yet its efficiency is severely constrained by rapid charge carrier recombination and the sluggish surface reaction kinetics of semiconductor photocatalysts. Herein, a synergistic strategy integrating sulfur vacancy (VS) engineering and intermetallic Ni4Mo alloy modification is developed to construct a Ni4Mo/MnCdS (MCS) heterojunction for enhanced PHE. In situ generated VS serve as anchoring sites for Ni4Mo growth, enabling strong interfacial coupling. The optimal Ni4Mo/MCS-VS catalyst features an exceptional H2 evolution rate of 30.1 mmol g-1 h-1 under visible light-6.3-fold and 5.2-fold higher than pristine MCS and MCS-VS, respectively. Experimental and DFT studies reveal that VS/Ni4Mo synergy optimizes the d-band center, establishes an internal electric field for directional charge transfer, and modulates H* adsorption thermodynamics, collectively suppressing carrier recombination and accelerating water reduction kinetics. This work provides a rational design paradigm for high-performance chalcogenide-based photocatalysts via defect engineering and alloy modification.

The salt [(C6H5)2P(C6H4)P]2[O3SCF3]2 which was synthesized via reductive P-P coupling of C6H4(PPh2)(PCl2), exhibits Lewis acidity derived from the σ*-orbitals of the central PP bond. This was evidenced by the Guttmann-Beckett test, the isolation of [(C6H5)2P(C6H4)P]2Br[O3SCF3] where bromide is associated with the P-P bond, and supported by computational studies.

The nickel cyclam complex (cyclam = 1,4,8,11-tetraazacyclotetradecane) remains one of the most selective and efficient catalysts for the electrochemically driven conversion of CO2 into CO in aqueous media. Although the mechanisms associated with CO2 electroreduction by this complex have been well investigated in homogeneous and heterogeneous cases, few computational studies so far have compared the effect of N- or C-substitution on the catalytic properties. Moreover, the effect of explicit water or counter-anion molecules has very rarely been considered in theoretical studies with this family of complexes. In that context, we have performed computational density functional theory investigations on the electrocatalytic reduction of CO2 by considering three different Ni complexes bearing cyclam-based ligands, which have been previously investigated. In-depth analysis for each step of the catalytic cycle has allowed us to draw general structure-reactivity relationships for both trans-I and trans-III isomers of each calculated structure.

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The combination of aluminum and carbon as a Lewis acid and base, respectively, to form an intramolecular Frustrated Lewis Pair (FLP) has been less explored compared to other combinations. Herein, we present the synthesis of a metallacyclic aluminum/carbon-based ambiphile and its reactivity towards carbonyl and isocyanate compounds. The aluminacyclobutene title compound Ph3PCH(CHCSiMe3)AltBu2 (3) was synthesized from an alkynyl-substituted phosphonium salt [Ph3PCH2CCSiMe3][Br] (2) and a diorganoalanate Li[tBu2AlH2]·2thf (1). The alanate 1 is structurally characterized and applied in a hydrometallation reaction. The obtained ylide-based ambiphile 3 shows typical FLP reactivity towards carbonyl compounds resulting in ring expansion, forming Ph3PCH(CHCSiMe3){(Ph)C(H)O}AltBu2 (4). In the reaction with phenyl isocyanate, a rearrangement reaction of the ambiphile was observed, which led to proton migration and the formation of an AlOCN heterocycle of the composition Ph3PC(CHCHSiMe3){(Ph)NCO}AltBu2 (6). The proton shuttling initially proceeds from the ylidic carbon atom to the isocyanate's nitrogen atom providing Ph3PC(CHCSiMe3){(PhNH)CO}AltBu2 (5), and finally to the carbon atom originally bonded to the aluminum atom. The experimental findings were rationalized through DFT calculations including an analysis of the rearrangement mechanism.

The rational design of matrix metalloproteinase (MMP) inhibitors, such as those targeted for MMP-14, prioritizes the native Zn(II) cofactor. The elevated levels of Cu(II), which are characteristic of the tumor microenvironment, are often overlooked. In this study, we investigated the Cu(II) coordination chemistry of selected MMP-14 inhibitors using potentiometric titrations, UV-Vis spectroscopy, circular dichroism, and density functional theory. Our findings reveal a striking inversion of metal selectivity in comparison with previously studied Zn(II) complexes. While Inhibitor 1 (Inh1) retains high specificity for the native Zn(II) active site, Inhibitor 4 (Inh4) exhibits exceptional thermodynamic stability with Cu(II) (pKd = 11.87). Inh4 favors copper over zinc by more than six orders of magnitude. This remarkable stability comes from a highly pre-organized, histamine-like mixed N/O donor environment and an extended poly-glycine tail. This tail adopts a 310-helical conformation that additionally stabilizes the coordination site and minimizes the entropic penalty of complexation. These results demonstrate that while Inh1 remains a highly specific candidate for targeted MMP-14 inhibition, the pronounced selectivity gap of Inh4 transforms it into a highly specific Cu(II) scavenger. This study highlights the critical risk of off-target metal sequestration in the tumor microenvironment while simultaneously opening the door to the potential repurposing of Inh4 as a targeted, copper-depleting agent in anti-angiogenic therapies.

Pristine LiNi0.5Mn1.5O4 and Ce-doped LiNi0.5Mn1.5-xCexO4 (x = 0.01, 0.03 and 0.05) were synthesized via a room-temperature solid-state method. The effects of Ce doping content on the structure, Mn3+ content, morphology, occupation of transition metal ions in the tetrahedral Li sites and electrochemical performance were systematically investigated. The measurements reveal that the cycling and rate performances of LiNi0.5Mn1.5O4 are primarily affected by Mn3+ content and the occupation of transition metal ions in the tetrahedral Li sites, respectively. In addition, the results demonstrate that moderate Ce doping can simultaneously inhibit Mn3+ formation and reduce the occupation of transition metal ions in the tetrahedral Li sites, thereby improving the cycling and rate performances of LiNi0.5Mn1.5O4. Among all samples, LiNi0.5Mn1.49Ce0.01O4, with a relatively low Mn3+ content and occupation of transition metal ions in the tetrahedral Li sites, exhibits the optimal electrochemical performance.

The effects of high pressure involved in solvothermal synthesis and crystallisation have been explored for Zn(II), Ni(II) and Co(II) imidazolium systems. Different synthetic protocols - including compression up to 3 GPa of solid oxides (ZnO and nano-ZnO) and salts Zn(NO3)2, Ni(NO3)2 and Co(NO3)2 together with imidazole and its derivatives, with or without the addition of a small amount of solvent, with or without heating; as well as the isochoric dissolution of the salts Zn(NO3)2, Ni(NO3)2 and Co(NO3)2 mixed with a stoichiometric amount of imidazole in water, with and without the addition of NH4OH - were designed to recognize the effect of pressure and temperature on the reaction outcome. An unprecedented high-density dia-Co(Im)2 with the structure composed of two interwoven 3-dimensional diamondoid networks, a new hydrate of 0-dimensional complex Co(HIm)6·2NO3·2H2O, and Ni(HIm)6·2NO3 have been obtained as single crystals at high pressure. Their specific features of highly compact packing testify to the systematic effects of pressure under solvothermal conditions.

Chronic wounds present a complex pathological microenvironment characterized by bacterial infection, excessive reactive oxygen species (ROS), persistent inflammation, and impaired tissue regeneration. Metal-organic frameworks (MOFs) are promising wound-healing materials because their coordination structures, porous architectures, and metal nodes can be chemically programmed to respond to pathological cues. This Frontier highlights three inorganic-chemistry principles governing MOF-mediated wound repair: coordination bond dynamics, pore-confined delivery, and metal-node reactivity. We discuss how acidity, redox-active species, competing ions, and protein-rich exudates regulate framework evolution and therapeutic ion release; how pore engineering enables host-guest matching and stimuli-gated delivery; and how metal nodes and heterostructures mediate ROS generation or scavenging. Key challenges include evaluating framework evolution in realistic wound fluids, distinguishing intrapore loading from surface adsorption, achieving stage-specific redox regulation, and ensuring safe degradation and metal-ion release.

The main theme of interest of the current study is to evaluate the electrochemical water splitting activity of Cu-cluster-based MOFs, generated using the node-spacer concept. Accordingly, a series of Cu-MOFs were constructed using an inorganic cluster, namely, the trinuclear Cu-pyrazolate [Cu3(μ3-OH)(μ-Pyz)3] (TCuP) moiety, as the node, and various halogen-substituted dicarboxylic acids as spacers. The recurrence of networks comprising the TCuP motif node not only supports the robustness and reproducibility of the synthetic strategy but can also be envisaged as successful improvisation for the periodic grafting of a potentially important water oxidation catalytic site inside the framework. Furthermore, strategically chosen linkers with immobilized halogens, in their part, vindicate our thematic aim of forming peripheral hedges to exert a positive impact on the local electronic environment of the OER site (TCuP) by instigating charge species formation as well as transportation, a potentially crucial facilitator for electrocatalysis. Comprehensive electrochemical water splitting studies under alkaline media were carried out to evaluate the importance of the TCuP-based MOFs as water oxidation catalysts. The results, presented in terms of overpotential, electrocatalytic surface area values and Tafel slopes, are gratifying and highly competitive to those of well-known published systems. Finally, the presence of Cu6 units, comprising two triangular hydroxy-bridged tris Cu-pyrazolate motifs, as nodes enhances the prospective use of these MOFs as magnetic materials. Accordingly, detailed magnetic studies of TCuP-2 and TCuP-3 were carried out, which show interesting magnetic features, including encouraging cryogenic magnetic refrigeration with respective -ΔSM values of 7 J kg-1 K-1 and 6.1 J kg-1 K-1 at T = 2 K for a field change of ΔH = 7 T.

We present a series of heteroleptic ruthenium chromophores that integrate bis-imidazole-2-ylidene (C^C)/4,4'-di-tBu-2,2'-bipyridine (N^N) or 4'-tBu-2,2':6',2″-terpyridine (N^N^N) as donor ligands paired with [2,2'-bipyridine]-4,4'-dicarboxylic acid (bpyA) as the acceptor/anchoring unit. These complexes exhibit broad visible light absorption extending to 630 nm. Incorporation of the C^C donor together with two bpyA anchors induces an ∼40 nm bathochromic shift, yielding a molar extinction coefficient of 29 100 M-1 cm-1 at 515 nm relative to the N^N^N-based analogue. The complexes display prolonged excited-state lifetimes in the 125-279 ns range, suitable for efficient electron injection into the TiO2 conduction band. Among the donor sets, the N-heterocyclic carbene-based C^C ligand enriches the ruthenium centre with electron density, lowering the Ru2+/3+ oxidation potential to 0.89 V below the I3-/I- redox couple, and enabling favourable dye regeneration. When integrated into dye-sensitized solar cells, the C^C-containing dye exhibits superior charge collection in the TiO2 conduction band, supported by an electron lifetime of ∼20 ns, and an enhanced photocurrent density. Quantum dynamics simulations further elucidate the structure-function relationships governing charge injection pathways in these photosensitizers.

A new series of MOFs (metal-organic frameworks) based on the lanthanides Ln = Sm-Lu and a fluorinated variant of benzene-1,3,5-tribenzoate (BTB3-) is presented. These compounds, named UoC-14(Ln) (UoC = University of Cologne), crystallize as pseudo-merohedral twins in the space group P21/c and possess permanent porosity as confirmed by gas sorption measurements (SBET = 723.8 m2 g-1 for Ln = Eu). Thermogravimetric analyses reveal the release of solvent molecules below 200 °C under inert conditions. The wide range of metal cations which can serve as nodes for this type of MOF enables the synthesis of luminescent framework materials whose properties are examined for Ln = Eu, Tb in detail. The 3F-BTB3- linker was shown to serve as an antenna, increasing the spectral absorption width of the material significantly, whereas the electron withdrawing fluorine substituents lead to the expected bathochromic shift. The crystal structure of UoC-14(Ln) is similar to a recently published structure for [Ln(BTB)DMF] (Ln = Y, Eu, Tb) with the unfluorinated linker. However, subtle differences occur. In order to gain a deeper understanding of the effect of the fluorination on the preferred geometry of the linker, DFT calculations and a detailed meta-analysis of the BTB linker system are carried out.

Hydrogenation of N2 to NH3 by the enzyme nitrogenase necessarily involves intermediates with H-N bonds. I propose a tactic for trapping these intermediates, through formation of stabilising hydrogen bonds using contiguous hydrogen bond acceptors in the reaction space. Wild type protein contains an aprotic reaction space, significantly bounded by α-70Val. The carboxylate sidechain of aspartate substituted at this position is capable of forming very good O⋯H-N hydrogen bonds with intermediates in proposed mechanisms. Alternatively, serine at this position can form O-H⋯N hydrogen bonds with N lone pairs on some intermediates. These expectations are elaborated with density functional optimisations of nine proposed intermediates and one transition state in the substituted proteins 70Asp, 70Ser and 70Glu. Possible outcomes are discussed, with the expectation that experiments in which these three substituted proteins undergo turnover with N2 could yield trapped intermediates on a time scale that permits their structural characterisation by crystal diffraction or cryoEM.