In this work, two magnesium-based metal-organic frameworks (Mg-MOFs) assembled from 1,4-naphthalinic acid (1,4-H2NDC) and pyridine-containing ligands, namely, 1,2-di(4-pyridyl)ethylene (L1) or 2-di(pyridin-4-yl)diazene (L2), are presented and characterized. In these two compounds, L1 or L2 acts as terminal ligands coordinated to Mg2+ ions in the binuclear second building units (SBUs) to generate two-dimensional (2D) [Mg2(1,4-NDC)2(H2O)(L)]& centerdot;6H2O networks (where L = L1 for 1 and L = L2 for 2). Although compounds 1 and 2 are constructed from ligands that are not intrinsically photoactive, both compounds exhibit photochromic behavior, representing the first reported two-dimensional (2D) photochromic Mg-MOFs achieved from coordination between Mg2+ and the non-photochromic organic ligands. Moreover, compound 1 displays bright blue luminescence and can function as a selective luminescent sensing material towards Fe3+ ions. When modified with CuI, it exhibits dual emission and shows luminescence sensing ability for cysteine (Cys) molecules as well. This work provides a useful reference for designing luminescent sensing MOFs using earth-abundant metals.

A pyridinium-functionalized CP was ultrasonically transformed into nanoparticles, delivering a recyclable photocatalyst for selective alcohol oxidation. Notably, water addition triggers 1O2 generation via ˙O2- and H2O interactions, markedly boosting selectivity. This work presents the first exploration of pyridinium-bearing CPs functioning as nanocatalysts for controlled photooxidation.

Bulk Copper(I) iodide (CuI) has been extensively investigated due to its interesting properties and promising applications in photodetectors, piezoelectrics, and transparent transistors. it forms multiple structural phases (α, β and γ), each exhibiting distinct structure-dependent properties, for example, the α- and β-CuI phases act as superionic conductors, whereas γ-CuI functions as a transparent p-channel transistor in p-n hetero/homojunction optoelectronic devices. Consequently, developing hybrid materials incorporating functional {CuxIy} modules with diverse structures is highly desirable. Coordination assembly, enabled by the formation of coordinate bonds between CuI and organic ligands, has proven to be an efficient strategy for synthesizing CuxIy(L)z hybrids (L = N-, S-, or P-based organic ligand). Further structural tunability can be achieved by constructing {CuxIy} modules within metal organic frameworks (MOFs), where various coordination modes between metal centers and organic linkers enable a broader range of architectures. Tailoring bulk CuI into discrete {CuxIy} motifs and periodically assembling them into ordered MOF frameworks under confined environments can lead to CuI-MOFs with enhanced structure-dependent properties distinct from those of pristine CuI. This review summarizes recent advances in CuI-MOFs, emphasizing the structural characteristics of {CuxIy} modules confined within MOFs and their associated applications. Our aim is to highlight a powerful approach for designing functionally tailored materials, featuring unique structures and customizable properties through the integration of functional inorganic modules into MOFs. For clarity, this review excludes CuxIy(L)z compounds constructed solely from {CuxIy} modules and organic ligands.

Metal-organic frameworks (MOFs), emerging as a promising class of chemiresistive sensing materials operating at room temperature (RT), have garnered substantial attention in recent years. Herein, through tuning the coordination modes between isonicotinic acid (HINA) and alkaline earth (AE, AE = Mg, Ca, Ba) metals with different radii and varied coordination numbers, the bulk CuI can be tailored into one-dimensional (1D) chain-like and 2D layered {Cu x I y } modules during coordination assembly, which are encapsulated within the AE-INA frameworks to obtain a series of AE-CuI-INA MOFs. Significantly, these AE-CuI-INA show selective and sensitive gas sensing performances toward NO2 working at room temperature, marking the first report of AE-CuI-INA MOFs for NO2 sensing. The sensing mechanism was examined through various experimental techniques, including but not limited to PXRD, X-ray photoelectron spectroscopy (XPS), and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). This work not only enriches the family of gas sensing MOFs but also provides valuable insights into the design of novel functional materials by utilizing {Cu x I y } modules as central sensing units.

Metal-organic frameworks (MOFs) possess high sensitivity as chemiresistive gas sensing materials at room temperature (RT), while their applications are severely hampered by the issues of slow recovery and poor recyclability. To address these challenges, a strategy integrating DFT calculation with experimental synthesis is developed to identify and remove non-essential active units with excessive interactions to gas molecules, thereby enhancing sensing recovery and recyclability. In a case study, DFT calculations reveal that one-dimensional (1D) {Cu4I3}nn+ chains in a K-MOF, K-CuI-K-INA (HINA = isonicotinic acid), exhibit strong affinity to NO2 while 2D {Cu4I5}nn- layers show moderate interactions. Thus, by modulating the structure features of CuI motifs in M-CuI-K-INA (M = Na+, K+, and Cs+, HINA = isonicotinic acid) type of MOFs, their NO2 sensing recovering and recycling performances are consequently optimized. Particularly, Cs-CuI-K-INA with solely 2D {Cu4I5}nn- layers possesses the best sensing recovery and recycle abilities, meanwhile maintains the excellent sensitivity and selectivity among these RT NO2 sensing materials presented in the current study. This approach paves the way for chemiresistive sensing materials with improved recoverability and recyclability while retaining high sensitivity and selectivity.

Metal-organic frameworks (MOFs), emerging as a promising class of chemiresistive sensing materials operating at room temperature (RT), have garnered substantial attention in recent years. Herein, through tuning the coordination modes between isonicotinic acid (HINA) and alkaline earth (AE, AE = Mg, Ca, Ba) metals with different radii and varied coordination numbers, the bulk CuI can be tailored into one-dimensional (1D) chain-like and 2D layered {CuxIy} modules during coordination assembly, which are encapsulated within the AE-INA frameworks to obtain a series of AE-CuI-INA MOFs. Significantly, these AE-CuI-INA show selective and sensitive gas sensing performances toward NO2 working at room temperature, marking the first report of AE-CuI-INA MOFs for NO2 sensing. The sensing mechanism was examined through various experimental techniques, including but not limited to PXRD, X-ray photoelectron spectroscopy (XPS), and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). This work not only enriches the family of gas sensing MOFs but also provides valuable insights into the design of novel functional materials by utilizing {CuxIy} modules as central sensing units.

By leveraging the dual photochemical activity of vinylpyridinium building blocks, the concurrent [2+2] photocycloaddition and photoinduced electron transfer are integrated within coordination polymer frameworks to achieve triple photoresponses, simultaneously generating photochromism, fluorescence modulation, and photomechanical actuation within a single crystalline system. The efficient photocycloaddition occurs in the interpenetrated framework despite the criss-crossed olefin arrangement, resulting in rapid stress accumulation and release that manifests as explosive photosalient behavior alongside optical switching. The framework-dependent ligand conformations produce distinct fluorescence readouts, allowing the progress of the cycloaddition to be monitored optically. When embedded in poly(vinyl alcohol) matrices, the crystal-level micro-strain is amplified into programmable macroscopic motions including straightening, crawling, and gathering under single-wavelength irradiation. This work provides a design strategy for integrating multiple photoresponses into a single material, contributing to programmable light-driven actuators and adaptive devices.

We decipher functions of three monooxygenases (PasO1, PasO3, and PasO4) in early biosynthetic steps in spirotetronate PA-46101 and demonstrate a PasO4/PasO3 cascade for forging the signature macrocyclic lactone. The P450 PasO4 oxidizes a methyl group to a carboxylate, enabling a regiospecific Baeyer-Villiger oxidation by PasO3. Structural analysis of a PasO3 homologue identifies a carboxylate-binding pocket essential for this strict substrate specificity. This two-enzyme cascade can serve as a portable biocatalytic tool for diversifying spirotetronates.

This study introduces a bimetallic alkali-metal coordination assembly approach to modulate the structural configurations of copper iodide (CuI) units within various Li-A-CuI-INA (A+ = Na+, K+, Rb+, and HINA denotes isonicotinic acid) coordination frameworks. By co-coordinating Li+ ions with other alkali metal ions (A+) in competition for binding with INA-, the 0D discrete CuI clusters found in the monometallic compound of Li-CuI-INA are transformed into extended 1D chain-like CuI modules, which are then stabilized within the resultant bimetallic Li-A-CuI-INA frameworks. Supported by DFT calculations, the Li-Rb-CuI-INA compound, featuring exclusively 1D stair-like {Cu4I4}n chains, was synthesized via this bimetallic coordination assembly strategy. This compound exhibits superior chemiresistive sensing performance for NO2 operating at room temperature (RT), rivaling the most effective sensing materials reported to date. This study highlights a promising strategy for the rational design of high-performing chemiresistive sensing materials through the integration of DFT computational insights with crystal engineering methodologies.

Due to their wide applications with regard to health and safety, sensitive and selective detection and distinguishing of alcohol molecules ( e.g. , methanol in counterfeit wine) is very important.

Due to their wide applications with regard to health and safety, sensitive and selective detection and distinguishing of alcohol molecules (e.g., methanol in counterfeit wine) is very important. Fluorescence (FL)-sensing materials towards probing alcohol molecules have been extensively developed based on their advantages of economy, convenience, and rapid detection. Herein, a fluorescent metal-organic framework (FL MOF) Cu2I2(pdc)4Sr4(DMF)6 (Sr-CuI-MOF, H2pdc = 3,5-pyridinedicarboxylic acid) featuring a three-dimensional (3D) structure was characterized. Sr-CuI-MOF exhibited a thermally activated delayed fluorescence arising from the Cu2I2-pdc motif. Upon exposure to methanol, Sr-CuI-MOF showed a sensitive and selective fluorescence redshift, characterized by a pronounced solvatochromism. Consequently, Sr-CuI-MOF could be used to accurately detect methanol by analyzing the linear relationship between the shift in emission wavelength or percentage of the fluorescence intensity quenching and methanol concentration. It represents the first CuI-bearing MOF with fluorescence detection of methanol. This work presents a novel approach to design FL-sensing MOFs that can be seen by the naked eye utilizing CuI-ligand motifs as building blocks and emission centers.

Activating silent biosynthetic gene clusters (BGCs) within various microorganisms is an important approach to uncover valuable natural products. In this study, we reported the capture and activation of two large silent BGCs from a marine-derived Streptomyces sp. SCSGAA 0027 in the heterologous host Streptomyces albus J1074 by inserting a widely used constitutive promoter kasOp∗ upstream of the core biosynthetic genes, which led to the production of coprisamides (COPs) and padanamides (PADs), respectively. Interestingly, the yields of COPs and PADs were significantly enhanced when potassium or sodium salts were supplemented in the fermentation media, especially 1 % KCl. The promoting strength of kasOp∗ was found to be obviously increased upon KCl addition by using the eGFP (enhanced green fluorescent protein) as an indicator. These findings revealed for the first time that the exogenous promoter kasOp∗ performed unexpectedly as a salt-enhanced element in S. albus J1074. Consequently, a "kasOp∗-KCl" strategy was developed to achieve the highest production of COPs A/B at 97.9 mg/L in fermentation with shaking flasks, along with the coproduction of a pair of new analogues, COPs E/F at 151.8 mg/L, leading to a maximum isolation titer of COPs at 171.7 mg/L, about 170-fold improvement comparing to previous reports. Similarly, the strategy increased the titers of the antimalarial agent PAD A to 76.7 mg/L and the diisonitrile copper chelator SF2768 to 72.8 mg/L in S. albus J1074, representing the highest yields reported to date for both compounds. Moreover, a small library of kasOp∗ variants were generated and validated to also be KCl-responsive, expanding the promoter toolkits for metabolic engineering and genome mining. These findings provide new insights into the salt-enhancing property of the widely used promoter kasOp∗, and offer a simple "kasOp∗-KCl" approach to efficiently activate silent BGCs and improve the production of the encoding natural products in multiple commonly used Streptomyces hosts.

Integrating dissimilar building units of discrete organic cages and inorganic clusters into single‐crystal supramolecular frameworks with tailored architectures and synergistic functions presents a significant challenge. Here, we presented our discovery of achieving such hybrids through electrostatically driven self‐assembly of cationic ammonium organic cages with anionic lead iodide clusters. Notably, by carefully modulating the size, shape, and composition of cationic organic cages, we have constructed an integrated porous host‐in‐host architecture. In this system, the internal cationic cage snugly resided, encapsulated within the external network constructed from anionic lead iodide clusters. This unique nested hierarchy showcased enhanced interhost interactions facilitated by electrostatic forces, which intricately tailored the electronic structure of the outer lead iodide moiety. As a result, the hybrid demonstrated distinguished photophysical properties, including efficient oxygen activation and enhanced photothermal conversion capability, as confirmed by comprehensive experimental and theoretical analyses. The critical role of interhost electrostatic interactions was further demonstrated through a systematic comparison with a structurally similar host‐in‐host architecture comprising lead iodide clusters and neutral amine cages. Furthermore, the integrated and compartmentalized dual‐host served as spatially isolated dual active sites for cascade reactions, exhibiting 33–47‐folds enhancement in activity compared to structural counterparts lacking charge cooperation.

Stimuli‐induced fluorescence in metal–organic frameworks is typically achieved by stimulating emissive organic centers in their frameworks. In this work, a {Cu 2 I 2 } cluster is incorporated in a Gd‐based metal–organic framework as part of a fluorescence center to yield [Gd 2 (Cu 2 I 2 )(L) 3 (DMF) 4 ]·(DMF) 0.5 (CH 3 CN) (Gd‐CuI‐MOF, H 2 L = 3, 5‐pyridinedicarboxylic acid). The Gd‐CuI‐MOF exhibits sensitive and reversible solvatochromic fluorescence between green and orange color, triggered by solvent molecules. Gd‐CuI‐MOF, as a colorimetric fluorescence sensor, shows considerable promise for applications in qualitative monitoring of organic reactions for specific industrial synthesis. It can also be used as an intriguing dual‐stimuli‐responsive (solvent and temperature) luminescent material in multiple information encryption, offering a sophisticated and accurate information protection system.

Stimuli-induced fluorescence in metal-organic frameworks is typically achieved by stimulating emissive organic centers in their frameworks. In this work, a {Cu2I2} cluster is incorporated in a Gd-based metal-organic framework as part of a fluorescence center to yield [Gd2(Cu2I2)(L)3(DMF)4](DMF)0.5(CH3CN) (Gd-CuI-MOF, H2L = 3, 5-pyridinedicarboxylic acid). The Gd-CuI-MOF exhibits sensitive and reversible solvatochromic fluorescence between green and orange color, triggered by solvent molecules. Gd-CuI-MOF, as a colorimetric fluorescence sensor, shows considerable promise for applications in qualitative monitoring of organic reactions for specific industrial synthesis. It can also be used as an intriguing dual-stimuli-responsive (solvent and temperature) luminescent material in multiple information encryption, offering a sophisticated and accurate information protection system.

Correction for 'The {Cu2I2} cluster bearing metal organic frameworks: crystal structures and fluorescence detecting performances towards cysteine and explosive molecules' by Jiang Jiang et al., Dalton Trans., 2024, 53, 706-714, https://doi.org/10.1039/d3dt03363e.

Two {Cu2I2} cluster-bearing metal organic frameworks (MOFs) of {[Eu(CuI)2(INA)3DMF]·0.95DMF}n (Eu-CuI-INA) and {K[(CH3)2NH2]Sr4(INA)2(DMF)2{(Cu2I2)2(INA)8}·2H2O}n (Sr-K-CuI-INA, HINA = isonicotinic acid, DMF = N,N-dimethyl formamide) were prepared and characterized in this work. Both materials feature a three-dimensional (3-D) structure, in which the {Cu2I2} clusters and Eu3+ (or Sr2+) metal ions are coordinated by INA- ligands with pyridine and carboxylic groups, respectively. Impressively, Sr-K-CuI-INA exhibits sensitive fluorescence sensing behaviors towards cysteine and nitro-bearing molecules, demonstrating potential FL sensing applications for bio and explosive molecules. This work would provide a good reference for designing fluorescent MOF probes containing CuI molecules.

Through effective regulation of active species in photocatalytic process, the oxidation or C(sp(3))-S bond cleavage upgrading of widespread aryl alkyl sulfides under mild conditions was successfully achieved by using a pyridinium photocatalyst. Benefiting from the excellent redox ability of the photocatalyst, the electron transfer between the pyridinium molecule and the substrate, molecular oxygen, or counter-anion effectively promotes the conversion and upgrading of the substrate thioether. Among them, the efficient generation of reactive oxygen species (ROS) enables the highly selective oxidation of sulfides to sulfoxides under visible light and air atmosphere. More importantly, the chlorine radical (Cl & sdot;) generated by electron transfer, reported for the first time, contributes to the cleavage of C(sp(3))-S bonds, achieving the transformation of aryl alkyl sulfides to disulfides. By harnessing the superior photocatalytic ability of pyridinium molecules, this work not only achieves the highly selective conversion of thioether by taming the active species in the photocatalytic process, but also sheds light on the untapped potential of chlorine radicals in the field of C(sp(3))-S bond activation and cleavage.

Naturally occurring resistances diminish the effectiveness of antibiotics, and present significant challenges to human health. Human activities are usually considered as the main drivers of the dissemination of antibiotic resistance, however, the origin of the clinical antibiotic resistance can be traced to the environmental microbes, and the clinically relevant resistance determinants have already pre-existed in nature before the antibiotics come into clinic. In this concept, we present the naturally occurring and widespread resistance determinants recently discovered during the biosynthesis study of bioactive compounds. These widely prevalent resistances in environmental microbes, including antibiotic producers and non-producers, advance the understanding of the origin of resistance, and provide prediction for the clinically relevant resistance to aid in the rational design of more effective drug analogues to combat resistance.

Correction for 'The {Cu2I2} cluster bearing metal organic frameworks: crystal structures and fluorescence detecting performances towards cysteine and explosive molecules' by Jiang Jiang et al., Dalton Trans., 2024, 53, 706-714, https://doi.org/10.1039/d3dt03363e.