Bis-azopyrazole Photoswitches for Efficient Solar Light Harvesting.

Although natural sunlight is one of the most abundant and sustainable energy resources, only a fraction of its energy is currently harnessed and utilized in photoactive systems. The development of molecular photoswitches that can be directly activated by sunlight is imperative for unlocking the full potential of solar energy and addressing the growing energy demands. Herein, we designed a series of 2-amino-1,3-bis-azopyrazoles that features a coupled πn system, resulting in a pronounced redshift in its spectral absorption, reaching up to 661 nm in the red region. By varying the amino substituents of these molecules, highly efficient E→Z photoisomerization under unfiltered sunlight can be achieved, with yields of up to 88.4%. Moreover, the Z,Z-isomers have high thermal stability with half-lives from days to years at room temperature. The introduction of ortho-amino substitutions and meta-bisazo units leads to a reversal of the n-π* and πn-π* transitions on the energy scale. This change provides a new perspective for further tuning the visible absorption of azo-switches by utilizing the πn-π* band instead of the conventional n-π* band. These results suggest that photoresponsive systems can be powered by sunlight instead of traditional artificial lights, thereby paving the way for sustainable smart materials and devices.

Solar Azo-Switches for Effective E→Z Photoisomerization by Sunlight.

Natural photoactive systems have evolved to harness broad-spectrum light from solar radiation for critical functions such as light perception and photosynthetic energy conversion. Molecular photoswitches, which undergo structural changes upon light absorption, are artificial photoactive tools widely used for developing photoresponsive systems and converting light energy. However, photoswitches generally need to be activated by light of specific narrow wavelength ranges for effective photoconversion, which limits their ability to directly work under sunlight and to efficiently harvest solar energy. Here, focusing on azo-switches-the most extensively studied photoswitches, we demonstrate effective solar E→Z photoisomerization with photoconversions exceeding 80 % under unfiltered sunlight. These sunlight-driven azo-switches are developed by rendering the absorption of E isomers overwhelmingly stronger than that of Z isomers across a broad ultraviolet to visible spectrum. This unusual type of spectral profile is realized by a simple yet highly adjustable molecular design strategy, enabling the fine-tuning of spectral window that extends light absorption beyond 600 nm. Notably, back-photoconversion can be achieved without impairing the forward solar isomerization, resulting in unique light-reversible solar switches. Such exceptional solar chemistry of photoswitches provides unprecedented opportunities for developing sustainable light-driven systems and efficient solar energy technologies.

Humidity-Controlled Molecular Assembly and Photoisomerization Behavior with a Bubble-Assisted Patterning Approach.

Precise control of molecular assembly is of great significance in the application of functional molecules. This work has systematically investigated the humidity effect in bubble-assisted molecular assembly. This work finds humidity is critical in the evolution of the soft confined space, leading to the formation of microscale liquid confined space under high humidity, and nanoscale liquid confined space under low humidity. It is also revealed that the differences in surface wettability and adhesion play the key role. Consequently, a flat pattern with thermodynamically favorable ordered structure and a sharp pattern with dynamically favorable disordered structure are achieved, which show different solid-state photoisomerization behaviors and photoresponsiveness. Interestingly, conductivity of sharp pattern with disordered structure is higher than that of flat pattern with layered ordered structure due to electronic transport mechanism of different spatial dimensions. This work opens a new way for manipulating the molecular self-assembly to control the morphology and function of molecular patterns.

Thiazolylazopyrazoles as Nonsymmetric Bis-Heteroaryl Azo Switches: High-Yield Visible-Light Photoisomerization and Increased Z-Isomer Stability by o-Carbonylation.

Following the progress on mono-heteroaryl azo switches (Het-N=N-Ph), a few bis-heteroaryl azo switches (Het-N=N-Het) have been studied recently, whereas the nonsymmetric bis-heteroaryl ones (Het1 -N=N-Het2 ) that can combine the respective merits of each heterocycle, have received little attention. Here we report thiazolylazopyrazoles as nonsymmetric bis-heteroaryl azo switches that combine the visible-light switching character of the thiazole ring and the ease of o-substitution of the pyrazole ring. Thiazolylazopyrazoles can achieve (near-)quantitative visible-light isomerization in both directions and long Z-isomer thermal half-lives of several days. In contrast to the drastically destabilizing effect of o-methylation, o-carbonylation of the pyrazole ring can remarkably stabilize Z isomers by inducing attractive intramolecular interactions (dispersion, C-H⋅⋅⋅N bond, and lone-pair⋅⋅⋅π interaction). Our work highlights the importance of the rational combination of two heterocycles and suitable structural substitution in developing bis-heteroaryl azo switches.

Efficient and Robust Molecular Solar Thermal Fabric for Personal Thermal Management.

Molecular solar thermal (MOST) materials, which can efficiently capture solar energy and release it as heat on demand, are promising candidates for future personal thermal management (PTM) applications, preferably in the form of fabrics. However, developing MOST fabrics with high energy-storage capacity and stable working performance remains a significant challenge because of the low energy density of the molecular materials and their leakage from the fabric. Here, an efficient and robust MOST fabric for PTM using azopyrazole-containing microcapsules with a deep-UV-filter shell is reported. The MOST fabric, which can co-harvest solar and thermal energy, achieves efficient photocharging and photo-discharging (>90% photoconversion), a high energy density of 2.5 kJ m-2 , and long-term storage sustainability at month scale. Moreover, it can undergo multiple cycles of washing, rubbing, and recharging without significant loss of energy-storage capacity. This MOST microcapsule strategy is easily used for the scalable production of a MOST fabric for solar thermal moxibustion. This achievement offers a promising route for the application of wearable MOST materials with high energy-storage performance and robustness in PTM.

Palladium-Catalyzed Regio- and Enantioselective Hydrosulfonylation of 1,3-Dienes with Sulfinic Acids: Scope, Mechanism, and Origin of Selectivity.

Chiral sulfones are important structural motifs in organic synthesis because of their widespread use in pharmaceutical chemistry. In particular, chiral allylic sulfones have drawn particular interest because of their synthetic utility. However, enantioselective synthesis of 1,3-disubstituted unsymmetrical chiral allylic sulfones remains a challenge. In this article, we report a protocol for (R)-DTBM-Segphos/Pd-catalyzed regio- and enantioselective hydrosulfonylation of 1,3-dienes with sulfinic acids, which provides atom- and step-economical access to 1,3-disubstituted chiral allylic sulfones. The reaction occurs under mild conditions and has a broad substrate scope. Combined experimental and computational studies suggest that the reaction is initiated by a ligand-to-ligand hydrogen transfer followed by a C-S bond reductive elimination via a six-membered transition state. Steric repulsion between the olefinic C-H of the substrate and the tert-butyl group of (R)-DTBM-Segphos was found to be a key factor in the enantiocontrol.

Hsa_circ_0001649 restrains gastric carcinoma growth and metastasis by downregulation of miR-20a.

BACKGROUND: Gastric carcinoma (GC) is a familiar carcinoma and serious threat to human health. We investigated the efficacy and mechanism of circular RNA hsa_circ_0001649 on the growth, migration, and invasion of GC cells. METHODS: microRNA (miR)-20a and hsa_circ_0001649 expression was investigated by RT-qPCR and was changed by cell transfection. CCK-8, flow cytometry, and BrdU assays were, respectively, used to investigate the efficacies of hsa_circ_0001649 and miR-20a on cell viability, apoptosis, and proliferation. Transwell assay was used to investigate the efficacies of hsa_circ_0001649 and miR-20a on cell migration and invasion. Moreover, the levels of cyclin D1, Bax, cleaved caspase-3, and signal pathway-related proteins were investigated by Western blot. RESULTS: Hsa_circ_0001649 was downregulated in GC cells and tissues. Upregulation of hsa_circ_0001649 restrained viability, proliferation, migration, and invasion, while promoted apoptosis. Furthermore, miR-20a was negatively regulated by hsa_circ_0001649 and miR-20a overexpression reversed the efficacy of hsa_circ_0001649 upregulation. Finally, upregulation of hsa_circ_0001649 restrained ERK and Wnt/ß-catenin pathways while miR-20a overexpression reversed these progresses. CONCLUSION: Upregulation of hsa_circ_0001649 restrained GC cell growth and metastasis by downregulating miR-20a and thereby inactivated ERK and Wnt/ß-catenin pathways.

Circular RNA circMAN2B2 promotes growth and migration of gastric cancer cells by down-regulation of miR-145.

BACKGROUND: CircMAN2B2 is a newly discovered circRNA that has been found to be an oncogene in lung cancer and glioma. The present study was designed to reveal the role of circMAN2B2 in gastric carcinoma (GC). METHODS: qRT-PCR method was utilized to examine circMAN2B2 expression in GC tissues and paracancerous tissues. Next, circMAN2B2 expression in SNU-16 and AGS cells was silenced by transfection. CCK-8 assay, colony formation assay, flow cytometer, Transwell assay, and Western blot were conducted for testing cell phenotype changes. Further, the downstream genes and signaling were uncovered by qRT-PCR and Western blot. RESULTS: As relative to paracancerous tissues, circMAN2B2 was high-expressed in GC tissues. Silence of circMAN2B2 clearly declined SNU-16 and AGS cells viability, survival, migration but enhanced apoptosis. Meanwhile, silence of circMAN2B2 induced the cleavage of caspases (-3 and -9), down-regulation of MMPs (-2 and -9), and up-regulation of miR-145. The impacts of circMAN2B2 silence toward SNU-16 and AGS cells were attenuated by miR-145 silence. Moreover, circMAN2B2 silence deactivated PI3K, AKT while activated JNK through regulating miR-145. CONCLUSION: This work presented the oncogenic function of circMAN2B2 in GC cells growth and migration. CircMAN2B2 exerted its function possibly through regulating miR-145 as well as PI3K/AKT and JNK pathways.

Circular RNA circHIAT1 inhibits proliferation and epithelial-mesenchymal transition of gastric cancer cell lines through downregulation of miR-21.

Gastric cancer (GC) is the third leading cause of cancer-related death worldwide. Circular RNA circHIAT1 has been proved to play an antitumor role. We aimed to explore the function and mechanism of circHIAT1 in GC. MKN28 and MKN45 cells were transfected with PLCDH-circHIAT1, miR-21 mimic, and relative control. Cell viability and apoptosis were examined through Cell Counting Kit-8 and flow cytometry, respectively. CircHIAT1 expression and other relative factors were tested through quantitative reverse transcription-polymerase chain reaction and Western blot analysis, respectively. Our findings demonstrated that circHIAT1 was lowly expressed in GC tissues. After transfection with PLCDH-circHIAT1 in MKN28 and MKN45 cells, cell viability was decreased, while the expression levels of p53 and p21 were raised, as well as apoptosis. Besides this, the epithelial-mesenchymal transition process was inhibited by PLCDH-circHIAT1 transfection. Mechanistically, miR-21 expression was upregulated in GC tissues and could be negatively regulated by circHIAT1. Further experiments showed that the addition of miR-21 mimic reversed the growth inhibition effects of circHIAT1 overexpression. Moreover, circHIAT1 inhibited the activation of phosphatase and tensin homolog/phosphatidylinositol 3 kinase/protein kinase B and extracellular signal-regulated kinase signal pathways via downregulating miR-21. CircHIAT1 functioned as a tumor inhibitor in GC cells through downregulating miR-21, and could be a novel target for GC treatment.

Silencing of long non-coding RNA PCAT6 restrains gastric cancer cell proliferation and epithelial-mesenchymal transition by targeting microRNA-15a.

Gastric cancer (GC) is a high mortality disease. We studied the function and mechanism of long non-coding RNA prostate cancer-associated transcript 6 (lncRNA PCAT6) on cell proliferation and epithelial-mesenchymal transition (EMT) in GC cells. CCK-8, flow cytometry and colony formation assay were respectively used to detect the cell viability, apoptosis and colony formation. PCAT6 and miR-15a expression were changed by cell transfection. Moreover, the level of Cyclin D1, p53, Bax, Cleaved caspase-3 and relate-proteins of EMT and cell pathways were investigated by Western blot. Besides, the level of miR-15a and PCAT6 was tested by RT-qPCR. Besides, the target relation between miR-15a and PCAT6 were tested by luciferase assay. PCAT6 was highly expressed in GC cells and tissues. Silencing of PCAT6 restrained the relate-proteins of cell proliferation and EMT. Furthermore, PCAT6 reversely regulated miR-15a and miR-15a inhibitor reversed the efficacy of sh-PCAT6 in cell proliferation and EMT. PCAT6 restrained the relate-proteins of RB/E2F and Wnt/ß-catenin pathways and miR-15a reverse this progress. Finally, PCAT6 was a target of miR-15a. Silencing of lncRNA PCAT6 restrained proliferation and EMT of GC cells by targeting miR-15a via RB/E2F and Wnt/ß-catenin pathways.

Stereodivergent Coupling of 1,3-Dienes with Aldimine Esters Enabled by Synergistic Pd and Cu Catalysis.

Herein we describe the use of synergistic Pd and Cu catalysis for stereodivergent coupling reactions between 1,3-dienes and aldimine esters. By using different enantiomers of the two metal catalysts, all four stereoisomers of the coupling products, which have two vicinal stereocenters, could be accessed with high diastereo- and enantioselectivity. This atom-economical cross-coupling reaction has a wide substrate scope and good functional group tolerance. Our work highlights the power of synergistic catalysis for asymmetric coupling reactions involving Pd-hydride catalysts.

The experimental and numerical investigation on the ballistic limit of BB-Gun pellet versus skin simulant.

The insufficient recognition of injuries by the BB-gun (regarded as toys for children) has led to its increasing misuse without permission, which has caused many public safety issues. Aiming to enhance the understanding of the injuries by the BB-gun, the experimental and numerical study of BB-Gun pellet penetrating "cowhide + gelatine" composite target was comprehensively carried out. It was confirmed from the experiment that BB-Gun is capable of inflicting severe or fatal wounds to important organs, and perforating the skin or not could be employed to evaluate the safety of BB-guns. Moreover, three forms of ballistic limit (including: velocity, kinetic energy and specific kinetic energy) of typical BB were calculated and analyzed by reasonably validated numerical simulation method. Additionally, a formulation was acquired by dimensional analysis based on the simulation results and was verified to accurately predict the ballistic limit velocity of BB with different mechanical properties. The method may help to improve the understanding on the minimal velocity needed to perforate skin and may be advised as the determination of the safety of BB-gun.

Long Noncoding RNA CAT104 Promotes Cell Viability, Migration, and Invasion in Gastric Carcinoma Cells Through Activation of MicroRNA-381-Inhibiting Zinc Finger E-box-Binding Homeobox 1 (ZEB1) Expression.

Gastric carcinoma (GC) remains the second leading cause of cancer-related deaths worldwide. Good biomarkers are of paramount importance for GC therapy. This study aimed to assess the role of long noncoding RNA (lncRNA) CAT104 in GC. We found that CAT104 was highly expressed in human GC NCI-N87, SGC7901, BGC823, BGC803, and AGS cells. Suppression of CAT104 decreased NCI-N87 cell viability, migration, and invasion, but promoted apoptosis. CAT104 knockdown enhanced the expression of microRNA-381 (miR-381) expression in NCI-N87 cells. miR-381 participated in the regulatory effects of CAT104 on NCI-N87 cell viability, migration, invasion, and apoptosis. Zinc finger E-box-binding homeobox 1 (ZEB1) was identified as a direct target of miR-381. Overexpression of ZEB1 reversed the miR-381 mimic-induced cell viability, migration, and invasion inhibition. Suppression of ZEB1 reversed the miR-381 inhibitor-induced activation of the c-Jun N-terminal kinase (JNK) pathway and Wnt/ß-catenin signaling pathways in NCI-N87 cells. In conclusion, CAT104 might function as an oncogenic factor in GC cells via regulating the expression of miR-381 and ZEB1.