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Color scheme: Reversibly photochromic crystals of (MV)Bi2Cl8 (methyl viologen, MV2+: N,N′‐dimethyl‐4,4′‐bipyridinium) show structural variations before and after UV irradiation. Color reversion is accomplished by heating in air (see picture). ([Bi2Cl8]2−)∞ double‐octahedral chains serve as electron donors to in situ generated MV2+ dications.

Uric acid is the end product of purine metabolism in humans. Hyperuricemia is a metabolic disease caused by the increased formation or reduced excretion of serum uric acid (SUA). Alterations in SUA homeostasis have been linked to a number of diseases, and hyperuricemia is the major etiologic factor of gout and has been correlated with metabolic syndrome, cardiovascular disease, diabetes, hypertension, and renal disease. Oxidative stress is usually defined as an imbalance between free radicals and antioxidants in our body and is considered to be one of the main causes of cell damage and the development of disease. Studies have demonstrated that hyperuricemia is closely related to the generation of reactive oxygen species (ROS). In the human body, xanthine oxidoreductase (XOR) catalyzes the oxidative hydroxylation of hypoxanthine to xanthine to uric acid, with the accompanying production of ROS. Therefore, XOR is considered a drug target for the treatment of hyperuricemia and gout. In this review, we discuss the mechanisms of uric acid transport and the development of hyperuricemia, emphasizing the role of oxidative stress in the occurrence and development of hyperuricemia. We also summarize recent advances and new discoveries in XOR inhibitors.

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Two structural series, including two isomorphous homodinuclear complexes Ln(2)(H(2)O)(4)(C(6)NO(2)H(4))(6) (Ln = Tb (1) and Er (2)) and four isostructural one-dimensional (1-D) chain-like assemblies [Ln(H(2)O)(4)(C(6)NO(2)H(4))(2)](n) x nCl (Ln = Sm (3), Eu (4), Tb (5), and Dy (6)), have been rationally prepared through a facile ultrasonic synthesis and have been characterized by X-ray diffraction and photophysical measurements. Both complexes, 1 and 2, feature a homodinuclear structure, based on two 8-fold coordination lanthanide atoms bridged by four nicotinic acid ligands. Complexes 3-6 are characterized by a 1-D polycationic chain-like structure, containing eight-coordinated lanthanide ions and bridging isonicotinic acid ligands. The 1-D polycationic chains and the isolated chloride anions are interconnected via hydrogen bonds and pi-pi interactions to form a three-dimensional supramolecular network. The effect of nicotinic/isonicotinic acid ligands on the structures and the photoluminescence properties, as well as the relationship between the photoluminescence properties and the structures, was investigated based on IR, UV-vis absorption spectra, low temperature phosphorescent spectra, excitation, and emission spectra. The fluorescence quantum yields of complexes 1 and 2 were determined to be 44% and 21%, respectively.

Lung cancer is one of the most malignant cancers around the world, with high morbidity and mortality. Metastasis is the leading cause of lung cancer deaths and treatment failure. MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs), two groups of small non-coding RNAs (nc-RNAs), are confirmed to be lung cancer oncogenes or suppressors. Transforming growth factor-β (TGF-β) critically regulates lung cancer metastasis. In this review, we summarize the dual roles of miRNAs and lncRNAs in TGF-β signaling-regulated lung cancer epithelial-mesenchymal transition (EMT), invasion, migration, stemness, and metastasis. In addition, lncRNAs, competing endogenous RNAs (ceRNAs), and circular RNAs (circRNAs) can act as miRNA sponges to suppress miRNAs, thereby mediating TGF-β signaling-regulated lung cancer invasion, migration, and metastasis. Through this review, we hope to cast light on the regulatory mechanisms of miRNAs and lncRNAs in TGF-β signaling-regulated lung cancer metastasis and provide new insights for lung cancer treatment.

The photocatalytic generation of hydrogen peroxide (H 2 O 2 ) from H 2 O and O 2 under visible light irradiation is a hopeful approach to achieve solar-to-chemical energy transformation. While the lack of specific redox reaction centers is still the main reason for low photocatalytic H 2 O 2 production efficiency, herein, we present a conjugated organic polymer (AQTEE-COP) containing anthraquinone redox centers by Sonogashira cross-coupling reaction between 2,6-dibromoanthraquinone (AQ) and 1,1,2,2-tetrakis(4-ethynylphenyl)ethene. The extended π-conjugated framework with an electron push−pull effect between electron-donating tetraphenylethene moieties and electron-withdrawing anthraquinone moieties not only broadened the visible light absorption range but also promoted the separation and migration of photo-induced charge carriers. Meanwhile, the anthraquinone moieties can serve as redox centers to accept photoinduced electrons and transfer them to adsorbed O 2 molecules for subsequent H 2 O 2 production. The well-defined structure of AQTEE-COP with task-specific anthracene redox centers provides molecular-level insights into the mechanistic understanding of the photocatalytic H 2 O 2 generation from H 2 O and O 2 . The AQTEE-COP exhibits efficient photocatalytic H 2 O 2 production with an initial rate of 3204 μmol g −1 h −1 under visible light (λ ≥ 400 nm) irradiation without any additional photosensitizers, organic scavengers, or co-catalysts. This article provides a protocol for the rational design of pre-functionalized conjugated organic polymerbased materials for solar-to-chemical energy transformation.

Two crystalline porphyrins, CuT(4'-OMePh)P (1) and H2T(4'-OMePh)P (2) (T(4'-OMePh)P(2-) = 5, 10, 15,20-tetrakis(4-methoxyphenyl)-21H,23H-porphyrin dianion), have been synthesized and characterized by a single-crystal X-ray diffraction. Compound 1 is crystallized in the orthorhombic system with a space group of Pna21, but compound 2 is crystallized in the monoclinic system with a space group of P2/c. Compound 1 is characterized as an isolated structure with a saddle-distorted nonplanar porphyrin macrocycle and an embedded cupric ion coordinating to four pyrrole nitrogen atoms. Nonmetalated compound 2 also displays an isolated structure, but the macrocycle of porphyrin is close to a perfect plane. The molecules in 2 are interconnected through five C-H · · · π hydrogen bonding interactions to yield a 3-D supramolecular network. However, the molecules in 1 are interlinked via five C-H · · · π interactions and two C-H · · · O hydrogen bonding interactions to yield a more complex 3-D supramolecular motif. The two more C-H · · · O hydrogen bonding interactions are attributed to the distortion of porphyrin macrocycle, resulting from the metalation. The metalation brought changes not only in the crystal structures and supramolecular motifs but also in the properties. The photophysical and redox properties of 1 and 2 in solution have also been studied by steady-state absorption and fluorescence, cyclic voltammetry, fluorescence lifetime and nanosecond transient absorption techniques.