Photocatalytic conversion of CO2 into multi-carbon products is severely constrained by the inefficient C–C coupling process, which remains a fundamental challenge in artificial photosynthesis. To address this limitation, we propose a molecular precursor engineering strategy based on a well-defined Cu3 cluster precursor (Cu3(PyCA)3, PyCA = pyrazolate-4-carboxaldehyde) to fabricate the Cu3@PCN photocatalyst, in which Cu species are highly dispersed on the PCN framework. The optimized catalyst exhibits exceptional performance in CO2-to-C2H5OH conversion, achieving a production rate of 8.26 µmol·g− 1·h− 1 with 87.8 Photocatalytic CO2 conversion to multi-carbon products is severely limited by inefficient C–C coupling, a fundamental challenge in artificial photosynthesis. Here we report a Cu cluster precursor-derived Cu3@PCN photocatalyst that delivers a C2H5OH production rate of 8.26 μmol·g-1·h-1 with 87.8
Four nickel(II) complexes derived from 1-(((2-(pyrrolidin-1-yl)ethyl)imino)methyl)naphthalen-2-ol (HL) were synthesized from nickel(II) acetate or nickel(II) nitrate in the absence or presence of ammonium thiocyanate or sodium azide, and their crystal structures and antibacterial activities were investigated. Reaction of HL with nickel(II) acetate afforded the centrosymmetric acetate/phenoxo-bridged trinuclear complex [Ni3(µ2-η1:η1-OAc)2(µ2-η2:η1-OAc)2L2] (1), whereas the reactions with nickel(II) acetate/NH4NCS, nickel(II) nitrate, and nickel(II) nitrate/NaN3 gave the mononuclear complexes [NiL(NCS)] (2), [Ni(HL)2](NO3)2 (3), and [NiL(N3)] (4), respectively. Single crystal X-ray diffraction shows that the identity and coordination preference of the anion markedly influence the nuclearity and coordination geometry of the products, although the four syntheses differ in more than one experimental variable. Complexes 2–4 are square planar, while complex 1 contains six-coordinate terminal and central nickel centres. Antibacterial assays show strain-dependent activity: 3 has the lowest MIC against B. subtilis (2.3 µM), 1 is the most active against S. aureus, E. coli and P. fluorescens, and 2 and 4 show MIC values identical to those of HL. These results demonstrate a strong anion-dependent structure-modifying effect and indicate that the antibacterial response is compound- and strain-specific.
The selective detection of Zn2⁺ is critically important owing to its essential roles in biological regulation, neurological signaling, and environmental systems. Among diverse fluorophoric platforms, quinoline-based scaffolds have attracted considerable attention as efficient Zn2⁺ sensing platforms due to their rigid π-conjugated architecture, strong metal-binding nitrogen site, and excellent photostability. This review critically summarizes research advances from 2011 to 2025 on quinoline-derived fluorescent probes developed for selective Zn2⁺ detection. Key fluorescence response mechanisms, including chelation-enhanced fluorescence, suppression of photoinduced electron transfer, and modulation of intramolecular charge transfer that govern signal transduction upon Zn2⁺ coordination, are discussed. Performance parameters such as detection limits, binding stoichiometry, solvent compatibility, pH responsiveness, and reversibility are systematically compared. Recent developments highlighting water-soluble probes, ratiometric systems, and bioimaging-capable sensors are also addressed, demonstrating the growing relevance of quinoline fluorophores in live-cell imaging and biomedical diagnostics. Finally, current challenges and future perspectives are outlined, focusing on improving in vivo applicability, real-time sensing, and multifunctional probe design.
Tetradentate pyrazole–biphenyl ligands offer tunable coordination chemistry for catalysis and bioactivity, but cross-domain structure–activity relationships are underexplored. The synthesized tetraethyl 1,1’,1’’,1’’’-(((3,3’-dimethoxy-[1,1’-biphenyl]-4,4’-diyl)bis(azanetriyl)) tetrakis(methylene))tetrakis(5-methyl-1 H-pyrazole-3-carboxylate) (ligand 3; 31.12
Hydrazone compounds have a wide range of biological activities and play an important role in coordination chemistry. In this study, four new copper(II), cobalt(II) and zinc(II) complexes, [Cu2L2(ONO2)2] (1), [Co2L2(EtOH)2(OH2)2](NO3)2 (2), [Co2L2(EtOH)2(OH2)2]Cl2 (3) and [ZnL2]n (4), where L is the deprotonated N'-(5-chloro-2-hydroxybenzylidene)-3-methylbenzohydrazide (HL), were prepared and structurally characterized. Molecular structures of the complexes were determined by single crystal X-ray diffraction. Complexes 1, 2 and 3 are dinuclear structures, and complex 4 is a polymeric structure. The tridentate hydrazone ligands in the complexes chelate to the metal centers through imino N, phenolate and carbonyl O atoms. Inhibitory effect of the four complexes on Jack bean urease was assayed. As a result, the copper(II) complex exhibited the best inhibitory effect (IC50 = 1.1 +/- 0.3 & micro;mol L-1), while the two cobalt(II) complexes showed moderate effects, and the zinc(II) complex had no activity.
