Biological thiols are important small molecule bioregulators that play important roles in numerous crucial processes and are directly associated with a variety of serious diseases. Consequently, sensing and imaging thiols have emerged as key research focuses. Fluorescent probes provide an important cornerstone for investigating the multifaceted roles of active thiols at the cellular level and in vivo with high sensitivity and selectivity. This review provides a systematic overview of the classification and structural properties of the fluorophores, functional groups and detection mechanisms for thiols. We focus on interesting breakthroughs of small molecule fluorescent probes for sensitive and selective sensing and imaging of thiols. We emphasize the strategies and chemical mechanisms behind the design of fluorescent probes and primarily describe the biological imaging, diagnostics and therapeutics. This review concludes with a discussion of the challenges and perspective for fluorescent probes, highlighting future avenues of research that should enable these probes to achieve accurate detection to enrich diagnostic and therapeutic tools for biomedical research and clinical applications.

The strong localized charges at the center of BiX6 octahedra in bismuth-based halide perovskite restrict carrier migration, ultimately affecting photocatalytic performance. However, whether A-site cations could suppress strong localized charges at the center of BiX6 remains unexplored, primarily because they indirectly contribute to the band-edge orbitals of halide perovskite. In this work, we reported a strategy to disperse strong localized charges at the center of BiX6 through changing organic A-site cations with conjugative effect (thiazoline, thiazole, and benzothiazole) and inductive effect (benzoxazole and benzoselenazole), and delve into the impact of the strategy on materials' optoelectronic and photocatalytic properties. Increased conjugative and inductive effects were found to suppress localized charges of BiBr6 center, improving carrier separation and transport, as well as improving photocatalytic CO2 conversion efficiency. Among these designed halide perovskites, benzoselenazole ammonium functionalized BSABiBr4 exhibited the highest CO2 conversion rate (mu mol g-1 h-1) of 36.20 with high reusability and stability. This finding successfully overcomes the limitation of A-site cations to suppress localized charges at the center of octahedra for enhancing photocatalytic performance.

This work reports the first example of rhodium-catalyzed asymmetric hydrogenation of 4-quinolone-2-carboxylic acids, providing direct access to chiral 2,3-dihydro-4-quinolones-a privileged scaffold in medicinal chemistry. Through systematic optimization of ligands, metal precursors, and solvents, the optimal catalytic system was identified as Rh(COD)2OTf combined with the chiral bisphosphine ligand (R,R)-Ph-BPE. The reaction proceeds smoothly under 40 atm of H2 in t-BuOH at 80 degrees C, affording a broad range of enantioenriched 2,3-dihydro-4-quinolones in moderate to excellent yields (40%-99%) and with high enantioselectivities (up to 99% ee). A broad range of substituents, including N-alkyl, N-benzyl, and electron-donating or electron-withdrawing groups on the quinolone core, are well tolerated, though the position and electronic nature of the substituents can affect enantioselectivity. Deuterium labeling experiments using D2/t-BuOH and D2/t-BuOD confirmed that molecular hydrogen (H2/D2) is the exclusive hydrogen source, with no direct participation of the protic solvent in the reduction step. Control experiments using C2-methyl or C2-ester substituted quinolones resulted in no conversion, demonstrating that the free carboxylic acid group is essential for substrate coordination to the rhodium center. Based on these findings and previous mechanistic studies, a plausible catalytic cycle is proposed involving oxidative addition of H2, carboxylate-directed substrate coordination, migratory insertion into the C=C bond, and reductive elimination. Gram-scale reactions successfully delivered the desired products in high yields (92%-95%) and enantioselectivity (88% ee). Furthermore, product derivatization successfully furnished a new class of non-natural chiral amino esters, underscoring the synthetic utility of this method for constructing pharmaceutically relevant scaffolds.

Unsaturated carbon–carbon bonds are fundamental building blocks in organic compounds. The difunctionalization of olefins allows for the rapid construction of drugs and complex molecular architectures. This transformation, which simultaneously installs two distinct functional groups across a carbon–carbon double bond, has therefore emerged as prominent research frontier in organic chemistry. In recent years, the synergy between photoredox and transition metal catalysis has emerged as a powerful and sustainable platform for constructing C-X bonds. This review covers advances since 2018 in the asymmetric difunctionalization of olefins enabled by synergistic visible light photoredox and transition metal catalysis, encompassing the construction of both carbon–carbon and carbon–heteroatom bonds. It systematically summarizes the reaction conditions, substrate scope, mechanisms, and merits and limitations of these catalytic systems, aiming to provide a useful reference for researchers in this field.

The asymmetric Henry reaction represents a powerful method for constructing chiral β-nitro alcohols; however, most existing catalytic systems suffer from poor recyclability, which limits their sustainable application. To address this challenge, based on the concept of green organocatalysis, this study is dedicated to developing a novel recyclable chiral catalytic system. A dual-core design strategy was adopted: (i) methoxy polyethylene glycol, which exhibits good biocompatibility, was selected as an environmentally friendly carrier; (ii) readily available L-tert-leucine was used as the precursor of the chiral catalytic center. A novel methoxy polyethylene glycol-supported chiral Schiff base ligand, L12, was successfully prepared. This ligand, in cooperation with copper acetate, facilitated the construction of a rationally designed catalytic system that exhibits remarkable activity for asymmetric Henry reactions. The system enables the efficient synthesis of various chiral β-nitro alcohols with considerable stereoselectivity. Notably, the catalytic system demonstrates satisfactory recyclability, further enhancing its practical value. Based on these performance advantages, the system shows significant application potential in the synthesis of chiral drug molecules and active intermediates. Overall, this work not only provides an efficient and recyclable protocol for the green synthesis of chiral β-nitro alcohols, but also offers a promising route for the sustainable preparation of key intermediates in chiral drug synthesis, highlighting its potential for industrial application.

Large it-conjugated system challenges the traditional notion of A-site cations non-participation in band-edge states for halide perovskites, tuning alkyl chain length to alter electrostatic interactions between the ammonium cations and octahedra, which modulates "valence band" (VB) edge states and photogenerated hole migration. However, how the conjugative and steric effects of A-site cations regulate band-edge states, particularly the photoreductive capability of photogenerated electrons at "conduction band" (CB) edge states, awaits systematic exploration. Herein, we reported a strategy for the direct regulation of band-edge states through varying A-site cations with different conjugated systems (phenyl/naphthyl). Increased conjugative effect benefits the CB edge and eliminates localized charge of BiBr6 center, while the spatially oriented 1-(2-naphthyl)meth-anamium (beta-NMA+) with minimized steric hindrance achieves deeper anchoring distance into octahedral cavity, significantly enhancing electrostatic interactions. The results reveal that beta-NMA+ functionalized perovskite (beta-NMA2BiBr5), conjugation-enhanced and low-steric-hindrance, exhibited the highest CO2 conversion efficiency which is 6.5 times higher than that of phenylmethylamium functionalized perovskite (PMA2BiBr5). This work validates a viable approach for regulating the ammonium-octahedron interaction via conjugative-steric strategy of A-site cations, significantly promoting catalytic capacity and offering a novel design pathway for efficient Bibased perovskite photocatalysts.

Lipid droplets (LDs) are multifunctional organelles essential for lipid storage, metabolic regulation, and cellular homeostasis, and their dysregulation is closely associated with the onset and progression of metabolic dysfunction-associated steatotic liver disease (MASLD). Sensitive and specific fluorescent imaging of LDs dynamics is crucial for elucidating MASLD pathogenesis and accelerating the development of effective therapeutics. Herein, we report near-infrared fluorescent carbon dots (NIR-FCDs) with precise LDs-targeting capability and enabling high-contrast imaging of LDs distribution in AML-12 cells and MASLD mice model, exhibiting high brightness (QY: 8.6%), deep-tissue penetration (75 μm), excellent photostability (>3 h continuous irradiation), and superior signal-to-background (SBR = 26). Leveraging these properties, NIR-FCDs was applied for visualizing pathological lipid accumulation in MASLD mice models and demonstrated their utility in a drug-screening platform successfully. This work developed a robust NIR-FCDs for LDs-specific imaging and highlighted its potential to advance mechanistic studies and therapeutic discovery in metabolic liver diseases.

The enantioselective Michael reactions of benzophenone-imine of glycine esters with phenol- and benzofuran-derived α,β-unsaturated pyrazolamides have been realized by using a chiral cyclopropenimine (Lambert catalyst, CSB-1) as an organocatalyst. In the presence of 20 mol % CSB-1, the Michael adducts were obtained in up to 85% yield and 98% ee under mild conditions. The configurations of these Michael products were deduced by X-ray single crystal diffraction of a pyroglutamic acid ester containing two adjacent stereocenters, which was obtained from in-situ acidic hydrolysis and lactamization of the corresponding Michael product.

TiO2 photocatalysis is limited by poor solar light utilization and rapid charge recombination. In this work, a benzothiadiazole-based small molecule (BTDSCN) was designed and combined with TiO2 to form a heterojunction for the simultaneous degradation of organic dyes and the reduction of Cr(VI). The introduction of BTDSCN increases the number of oxygen vacancies (VO) in TiO2, effectively boosting the availability of photocatalytic active sites. Compared to TiO2, the BTDSCN/TiO2 heterojunction exhibits improved performance in degrading organic dyes and reducing Cr(VI). The removal efficiencies for Rhodamine B and Cr(VI) are approximately 2 times and 7 times higher than those of TiO2, respectively. The abundant VO in BTDSCN/TiO2 creates defect levels within its band gap, significantly enhancing the photocatalytic activity of TiO2.

The development of asymmetric hydrogenation (AH) catalysts that achieve over a million turnover numbers (TONs) with high enantioselectivity for the industrial production of chiral compounds remains a major challenge. We report a novel class of readily accessible, ferrocene-based PNNO tetradentate ligands for the Ir-catalyzed asymmetric hydrogenation of ketones. This system delivers exceptional performance in the hydrogenation of acetophenone, reaching a TON of up to 4,080,000 with 98% ee. It exhibits a broad substrate scope, successfully hydrogenating 87 diverse ketones with high efficiency and excellent enantioselectivity. Mechanistic studies by DFT calculation reveal the critical role of the phenolic hydroxyl group in ligand and the significant boost in performance provided by a -CF3 substituent. DIAS and IGMH analysis reveal the high reactivity and stereoselectivity is promoted by stabilizing weak noncovalent interactions in the S-configured transition state. The practical utility is highlighted by the gram-scale synthesis of key pharmaceutical intermediates, showcasing great potential for industrial application.

Inorganic lead halide perovskite quantum dots (PQDs) feature exceptional optoelectronic properties but suffer from poor stability, limiting their commercial viability. This study employs a mechanochemical synthesis route utilizing shared cesium ion to synthesize CsPbBr3 PQDs within supramolecular γ-cyclodextrin metal-organic frameworks (γ-CD-MOFs). The resulting CsPbBr3@γ-CD-MOFs achieves high photoluminescence quantum yield (73%) alongside exceptional thermal, photochemical, and environmental stabilities. Mechanistic investigations reveal synergistic augmentation effects: multianchored defect passivation via γ-CD hydroxyl groups, enhanced radiative recombination through type-I heterojunction-driven directional carrier injection, and suppression of ion migration and phase separation by MOFs' physical barriers and interfacial chemical bonds. The composite was successfully applied in white light-emitting diodes, boasting color rendering index of 90.1 and color gamut coverage of 115%. Furthermore, benefiting from the good biocompatibility imparted by γ-CD-MOFs, the composite serves as fluorescent probe for specific labeling and imaging of lysosomes in living cells. This supramolecular-MOFs strategy provides design principles for developing stable, efficient, and biologically compatible PQDs, accelerating their optoelectronic and bioimaging applications.

ABSTRACT Prostate cancer (PCa) is a leading malignancy in men globally. Although serum prostate‐specific antigen (PSA) testing is prevalent for PCa screening, its inherent limitation in specificity and sensitivity frequently leads to high false‐positive and false‐negative diagnoses. To address this challenge, we present a PSA+ strategy that integrates a clinically defined PSA threshold (10 ng/mL) with a pair of complementary near‐infrared (NIR) fluorescent probes: a zinc‐complex‐based probe (Cy‐O‐NS‐a‐Zn) targeting the zinc transporter solute carrier family 39 member 1 (SLC39A1), and a glutamate‐urea‐lysine (Glu‐Urea‐Lys) ligand‐based probe (Cy‐S‐Glu) targeting prostate‐specific membrane antigen (PSMA). This combinatorial approach accurately discriminates PCa from normal prostate cells, delineates tumor margins in patient‐derived xenograft (PDX) mouse models with robust tumor‐to‐background ratios (TBR), and enables fluorescence‐guided surgery. Importantly, a double‐blind histopathological validation using 70 cases of human prostate tissue specimens revealed that the PSA+ strategy substantially outperformed PSA testing alone, improving diagnostic specificity from 70% to 97.6% and sensitivity from 75% to 96.8%. Collectively, this work provides a rapid, accurate, and comprehensive diagnostic paradigm that complements standard PSA testing, thereby refining clinical diagnosis and decision‐making in PCa.

Since the first chiral cylcopropenimine (CPI) was reported by Lambert and colleagues in 2012, this type of chiral organosuperbase has been used to catalyze asymmetric Michael reactions, Mannich reactions, and [3 + 2] cyclization reactions in high to excellent yields and stereoselectivities. In this mini-review, we have provided a comprehensive overview of chiral cyclopropenimines, including their structural features, preparation, versatility in asymmetric synthesis, and mechanistic studies. Furthermore, we have offered a perspective on the future development of this new class of chiral organosuperbases.

A novel chiral P*NN ligand featuring a P-chirality has been synthesized, and its catalytic properties in Manganese(I)-catalyzed asymmetric hydrogenation and asymmetric transfer hydrogenation of ketones are investigated. A broad range of substrates (42 examples) are hydrogenated, delivering a series of chiral alcohols with outstanding yields (>90%) and good enantioselectivities (up to 92% ee). In addition, a plausible catalytic cycle is performed through deuterium-labeling experiments and high-resolution mass spectrometry analysis.

Solar-driven photocatalytic CO2-to-CH4 conversion represents a promising strategy to mitigate the energy and climate crisis. However, it is still challenging to achieve efficient CO2 conversion due to the difficulties of CO2 activation, sluggish kinetics of water oxidation half-reaction and high cost of sacrificial agents in conventional reaction systems. Herein, by precisely integrating bimetallic sulfide with functionalized UiO-66 to construct a Cu0.1Zn0.9S/Bim-UiO-66 S-scheme heterojunction photocatalyst, which innovatively accomplished complete CO2 methanation and benzimidazole synthesis in one redox cycle. Experimental results reveal that the optimized photocatalyst exhibited an exceptional CH4 production rate of 35.2 mu mol h- 1 g- 1 (selectivity of 100 %) and 92 % benzimidazole conversion under simulated solar irradiation. Mechanistic studies demonstrate that the S-scheme heterojunction significantly enhances photogenerated charge carrier separation efficiency through the establishment of a built-in electric field, while preserving the strongest redox potentials of the two semiconductors. Remarkably, the benzimidazole synthesis process replaced conventional H2O oxidation, proving beneficial for CO2-to-CH4 conversion. This work provides new insights into designing high-performance photocatalysts for CO2 conversion and the synthesis of fine chemicals.

Fluorescence imaging-guided photodynamic therapy (PDT) offers immense clinical potential for cancer treatment. However, their therapeutic efficacy and biosafety are compromised by the high oxygen dependency of traditional Type II photosensitizers and insufficient targeting accuracy. Herein, we present a tumor-organelle-targeted and activatable phototheranostic platform (termed NO2/BDP-BT), which was engineered via an atom-economical all-in-one design strategy. The NO2/BDP-BT gathers exceptional tumor-organelle targeting ability, nitroreductase (NTR)-activated fluorescence enhancement, allowing it to monitor hypoxia levels in biosystems (living cells, clinical patient tissues, and in vivo). Moreover, it enables the generation of Type I/II reactive oxygen species (ROS) in situ after NTR activation, thereby suppressing tumor growth with an inhibition rate of 93.2 % via mitochondria-mediated apoptosis and potentiating the antitumor immunity response. Cocrystal structural analysis of the NTR protein in complex with the precursor of NO2/BDP-BT (PDB: 7XWW; resolution: 2.80 Å) first reveals that multiple non-covalent interactions (e.g., hydrogen bonding and π-π stacking) make it anchor in the catalytic environment with high affinity. Moreover, NO2/BDP-BT can be expanded to a Type I PDT photosensitizer (NO2/BDPS-BT) by introducing a thiophene unit, conquering hypoxia restriction in PDT. This work establishes a molecular platform of activatable phototheranostic sensor with potent therapeutic efficacy and biosafety, which would effectively address both hypoxia resistance and targeting deficiencies inherent in conventional PDT.

A palladium catalytic system incorporating novel Fc-JosiPhos ligands enables efficient C-N bond formation with diverse (hetero)aryl halides under low palladium loading (0.1 mol%). We rationally designed novel ferrocenyl phosphine-derived JosiPhos ligands (L1-L3). These ligands incorporate a ferrocenyl group providing greater steric bulk than tert-butyl or cyclohexyl and superior electron donation to cyclohexyl, along with a tunable side chain. They delivered excellent yields in the catalytic coupling of challenging (hetero)aryl chlorides with hydrazine. The scalable synthesis of arylhydrazines (5 mmol scale) and subsequent cyclization to pyrazoles (65%-91% yields) highlights their potential for industrial conversion. Furthermore, the modularity of this strategy supports late-stage pharmaceutical functionalization, exemplified by TRPC inhibitor intermediate.

A modular protocol that achieved the efficient synthesis of imidazo[2,1-b][1,3,4]thiadiazoles/selenadiazoles via using easily available N-tosylhydrazones, chalcone derivatives, and KSCN/KSeCN is proposed. The method overcomes the elongated synthesis steps and prefunctionalized synthons of previous methods. It solves the problem of traditional preparation methods, which makes it difficult to synthesize thickened selenium-containing heterocyclic molecules, further expanding the number of members in its family. The fluorescence of these compounds also reveals the potential values of the scaffolds we synthesized.