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Research has been conducted on the spiroisoxazolinoproline-based amino acid derivatives. The route to these derivatives developed via the reaction of exo-methyleneprolinate as a dipolarophile with nitrile oxides in generating diastereoselective spiroisoxazolinoprolinates is described.

Research has been conducted on benzo[c]quinolizines and 4-hydroxycoumarins. The ipso substitution preparation method of these compounds has been developed and the details are reported.

Depression is a neuropsychiatric disease that significantly impacts the physical and mental health of >300 million people worldwide and places a major burden on society. Ginsenosides are the main active ingredient in ginseng and have been proven to have various pharmacological effects on the nervous system. Herein, we investigated the antidepressant effect of ginsenoside Rk3 and its underlying mechanism in a murine model of depression. Rk3 significantly improved depression-like behavior in mice, ameliorated the disturbance of the hypothalamus-pituitary-adrenal axis, and alleviated neuronal damage in the hippocampus and prefrontal cortex of mice. Additionally, Rk3 improved the abnormal metabolism of tryptophan in brain tissue by targeting tryptophan hydroxylase, thereby reducing neuronal apoptosis and synaptic structural damage in the mouse hippocampus and prefrontal cortex. Furthermore, Rk3 reshaped the composition of the gut microbiota of mice and regulated intestinal tryptophan metabolism, which alleviated intestinal barrier damage. Thus, this study provides valuable insights into the role of Rk3 in the tryptophan metabolic cycle along the brain-gut axis, suggesting that Rk3 may have the potential for treating depression.

Foot activity can reflect numerous physiological abnormalities in the human body, making gait a valuable metric in health monitoring. Research on flexible sensors for gait monitoring has focused on high sensitivity, wide working range, fast response, and low detection limit, but challenges remain in areas such as elasticity, antibacterial activity, user-friendliness, and long-term stability. In this study, we have developed a novel capacitive pressure sensor that offers an ultralow detection limit of 1 Pa, wide detection ranges from 1 Pa to 2 MPa, a high sensitivity of 0.091 kPa -1 , a fast response time of 71 ms, and exceptional stability over 6000 cycles. This sensor not only has the ability of accurately discriminating mechanical stimuli but also meets the requirements of elasticity, antibacterial activity, wearable comfort, and long-term stability for gait monitoring. The fabrication method of a dual dielectric layer and integrated composite electrode is simple, cost-effective, stable, and amenable to mass production. Thereinto, the introduction of a dual dielectric layer, based on an optimized electrospinning network and micropillar array, has significantly improved the sensitivity, detection range, elasticity, and antibacterial performance of the sensor. The integrated flexible electrodes are made by template method using composite materials of carbon nanotubes (CNTs), two-dimensional titanium carbide Ti 3 C 2 T x (MXene), and polydimethylsiloxane (PDMS), offering synergistic advantages in terms of conductivity, stability, sensitivity, and practicality. Additionally, we designed a smart insole that integrates the as-prepared sensors with a miniature instrument as a wearable platform for gait monitoring and disease warning. The developed sensor and wearable platform offer a cutting-edge solution for monitoring human activity and detecting diseases in a noninvasive manner, paving the way for future wearable devices and personalized healthcare technologies.

Two-dimensional conjugated metal-organic frameworks (2D c-MOFs) have attracted increasing interest in electronics due to their (semi)conducting properties. Charge-neutral 2D c-MOFs also possess persistent organic radicals that can be viewed as spin-concentrated arrays, affording new opportunities for spintronics. However, the strong π-interaction between neighboring layers of layer-stacked 2D c-MOFs annihilates active spin centers and significantly accelerates spin relaxation, severely limiting their potential as spin qubits. Herein, we report the precise tuning of the charge transport and spin dynamics in 2D c-MOFs via the control of interlayer stacking. The introduction of bulky side groups on the conjugated ligands enables a significant dislocation of the 2D c-MOFs layers from serrated stacking to staggered stacking, thereby spatially weakening the interlayer interactions. As a consequence, the electrical conductivity of 2D c-MOFs decreases by 6 orders of magnitude, while the spin density achieves more than a 30-fold increase and the spin-lattice relaxation time ( T 1 ) is increased up to ∼60 μs, hence being superior to the reference 2D c-MOFs with compact stackings whose spin relaxation is too fast to be detected. Spin dynamics results also reveal that spinless polaron pairs or bipolarons play critical roles in the charge transport of these 2D c-MOFs. Our strategy provides a bottom-up approach for enlarging spin dynamics in 2D c-MOFs, opening up pathways for developing MOF-based spintronics.

Although two-dimensional conjugated metal-organic frameworks (2D c -MOFs) provide an ideal platform for precise tailoring of capacitive electrode materials, high-capacitance 2D c -MOFs for non-aqueous supercapacitors remain to be further explored. Herein, we report a novel phthalocyanine-based nickel-bis(dithiolene) (NiS 4 )-linked 2D c -MOF (denoted as Ni 2 [CuPcS 8 ]) with outstanding pseudocapacitive properties in 1 M TEABF 4 /acetonitrile. Each NiS 4 linkage is disclosed to reversibly accommodate two electrons, conferring the Ni 2 [CuPcS 8 ] electrode a two-step Faradic reaction with a record-high specific capacitance among the reported 2D c -MOFs in non-aqueous electrolytes (312 F g -1 ) and remarkable cycling stability (93.5% after 10,000 cycles). Multiple analyses unveil that the unique electron-storage capability of Ni 2 [CuPcS 8 ] originates from its localized lowest unoccupied molecular orbital (LUMO) over the nickel-bis(dithiolene) linkage, which allows the efficient delocalization of the injected electrons throughout the conjugated linkage units without inducing apparent bonding stress. The Ni 2 [CuPcS 8 ] anode is used to demonstrate an asymmetric supercapacitor device that delivers a high operating voltage of 2.3 V, a maximum energy density of 57.4 Wh kg -1 , and ultralong stability over 5000 cycles.

Pentosinane is a structurally complex nonenzymatic post-translational modification of proteins believed to be present in all living things. It falls into the category of advanced glycation end products (AGEs) and is structurally related to the other AGEs pentosidine and glucosepane. Although pentosidine and glucosepane have been widely studied for their role in wide-ranging conditions (e.g., diabetes mellitus, Alzheimer's disease, and human aging), relatively little is known about pentosinane. Interestingly, previous reports have suggested that pentosidine may derive from pentosinane. The (patho)physiological significance of pentosinane in humans is largely unexplored. As a first step to address this knowledge gap, we report herein the first total synthesis of pentosinane. Our synthesis is high yielding (1.7% over seven steps), concise, and enantioselective, and it leverages a strategy for synthesizing 2,5-diaminoimidazoles previously developed by our lab. Access to synthetic pentosinane has allowed us to perform additional studies showing that its oxidation to pentosidine is both pH and oxygen dependent and is substantially slower under physiological conditions than previously believed. Additionally, pentosinane rapidly decomposes under harshly acidic conditions typically employed for pentosidine isolation. Taken together, these results suggest that pentosinane is likely to be more abundant in vivo than previously appreciated. We believe these results represent a critical step toward illuminating the role(s) of pentosinane in human biology.

Advanced supercapacitor electrodes require the development of materials with dense redox sites embedded into conductive and porous skeletons. Two-dimensional (2D) conjugated metal-organic frameworks ( c -MOFs) are attractive supercapacitor electrode materials due to their high intrinsic electrical conductivities, large specific surface areas, and quasi-one-dimensional aligned pore arrays. However, the reported 2D c -MOFs still suffer from unsatisfying specific capacitances and narrow potential windows because large and redox-inactive building blocks lead to low redox-site densities of 2D c -MOFs. Herein, we demonstrate the dual-redox-site 2D c -MOFs with copper phthalocyanine building blocks linked by metal-bis(iminobenzosemiquinoid) (M 2 [CuPc(NH) 8 ], M = Ni or Cu), which depict both large specific capacitances and wide potential windows. Experimental results accompanied by theoretical calculations verify that phthalocyanine monomers and metal-bis(iminobenzosemiquinoid) linkages serve as respective redox sites for pseudocapacitive cation (Na + ) and anion (SO 4 2- ) storage, enabling the continuous Faradaic reactions of M 2 [CuPc(NH) 8 ] occurring in a large potential window of -0.8 to 0.8 V vs Ag/AgCl (3 M KCl). The decent conductivity (0.8 S m -1 ) and high active-site density further endow the Ni 2 [CuPc(NH) 8 ] with a remarkable specific capacitance (400 F g -1 at 0.5 A g -1 ) and excellent rate capability (183 F g -1 at 20 A g -1 ). Quasi-solid-state symmetric supercapacitors are further assembled to demonstrate the practical application of Ni 2 [CuPc(NH) 8 ] electrode, which deliver a state-of-the-art energy density of 51.6 Wh kg -1 and a peak power density of 32.1 kW kg -1 .

Molybdenum disulfide (MoS 2 ) has shown large promise in harvesting osmotic energy. However, the current investigations generally focus on proof-of-concept nanoscale single-pore devices with a semiconductor phase structure. Exploration of the application viability of MoS 2 in a more robust macroscopic-scale two-dimensional (2D) nanofluidic membrane and acquisition of fundamentals of how the phase structure influences the power generation process are highly demanded. Here, we demonstrate that robust and stable composite membranes made up of 2D metallic MoS 2 can act as high-performance osmotic power generators. Both experiment and simulation reveal that the higher electron density of metallic MoS 2 increases the affinity of cations to the surface, which renders the system excellent ion selectivity and high ionic flux and greatly promotes transmembrane ion diffusion. When natural river water and seawater are mixed, the power density can achieve about 6.7 W m -2 . This work shows the great potential of metallic MoS 2 in nanofluidic energy devices.

An indane-based, bifunctional, chiral selenide catalyst has been developed. The new catalyst is efficient for the enantioselective synthesis of saturated azaheterocycles possessing a trifluoromethylthio group. The desired products were obtained in good yields with high diastereo- and enantioselectivities.

This paper investigates the pH-responsive self-assembly of an amphiphilic carboxyl-terminated polyester dendrimer, H20-COOH, in aqueous solution using the dissipative particle dynamics method. The electrostatic interactions were described by introducing the explicit interaction between the smeared charges on ionized polymer beads and the counterions. The results show that the self-assemblies could change from unimolecular micelles, microphase-separated small micelles, wormlike micelles, sheetlike micelles, and small vesicles to large vesicles with the decrease in the degree of ionization (α) of carboxylic acid groups. In addition, the detailed self-assembly mechanisms and the molecular packing models have also been disclosed for each self-assembly stages. Interestingly, the wormlike micelles are found to change from linear to branched when α decreases from 0.182 to 0.109. The current work might serve as a comprehensive understanding on the effect of carboxylic acid groups on the self-assembly behaviors of dendritic polymers.

An efficient approach to vicinal trifluoromethylthioamination of alkenes with a broad substrate scope catalyzed by electron-rich diaryl selenide has been developed. This intermolecular amination strategy was successfully applied to SCF3-esterification of alkenes using weak acids as nucleophiles.