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[Display omitted] • Highly dispersed copper species are successfully constructed in 20CuCe. • The oxidized Cu species are proved as actives sites. • The bulk oxygen in CeO 2 diffuses to surface to keep Cu species oxidized. • New recognitions in the interaction between copper and ceria for the WGSR. To prepare supported catalysts with high loading and high dispersion of active metals is a crucial challenge in heterogeneous catalysis. Here we report the fabrication of very reactive catalyst that contains finely dispersed copper with 20 wt% content supported on high-surface area CeO 2 for the water–gas shift (WGS) reaction. This copper-ceria catalyst shows superb activity with a CO consumption rate of 116.7 μmol CO g cat -1 s−1 at 300 ℃, nearly one order of magnitude more active than other copper-based catalysts ever reported. Based on the precise and integrated characterizations, the oxidized not the metallic Cu are proved to be active centers where the adsorbed CO directly reacted with bridged —OH groups to finish the WGS reaction. The oxidized Cu sites are confirmed to be originated from the activation effect from Cu to CeO 2 , which promotes the oxygen of CeO 2 diffuse from the bulk to surface, making Cu oxidized even under reductive atmosphere. [ABSTRACT FROM AUTHOR]

Emerging fungal phytodiseases are a food security threat and novel fungicides are in an urgent need. Herein, a series of isobutyrophenone derivatives were designed and synthesized. The derivatives exhibited excellent fungicidal activities against seven fungi. The structure-activity relationship (SAR) study indicated that the introduction of a bromo group at the position 3 or 5 of the phenyl ring, as well as esterification of the 4-hydroxy with a chloroacetyl group, could substantially increase the antifungal activity and spectrum of the compounds. Among all 23 compounds, 2-bromo-3-hydroxy-4-isobutyryl-6-methylphenyl 2-chloroacetate (12b) showed the highest fungicidal activity against all seven tested fungal pathogens with EC 50 values ranging from 1.22 to 39.94 μg/mL and exhibited the most potent inhibition against class II fructose-1,6-bisphosphate aldolase with an IC 50 of 3.63 μM. The lead compounds were proven to be safe to NIH3T3/293 T cells and silkworm larvae, and relatively stable under different harsh conditions. Detached fruit tests showed the practical potential of lead compounds for fruit (or plant) protection. Taken together, our results indicated that the isobutyrophenone derivatives could be further optimized and developed as advanced leads for new fungicides. Unlabelled Image • Novel isobutyrophenone analogs were designed and synthesized. • 2-bromo-3-hydroxy-4-isobutyryl-6-methylphenyl 2-chloroacetate (12b) showed potent broad-spectrum antifungal activity. • Compound 12b exhibited relative stable and non-toxic properties. • Compound 12b could control C. gloeosporioides infection on detached fruit. [ABSTRACT FROM AUTHOR]

• The reactivity of Au/TiO 2 -1 0 1 was higher than Au/TiO 2 -0 0 1 during CO oxidation. • Diverse gold status induced different CO adsorption behavior. • The crystal plane of support strongly affected the surface carbonate species. • Different ability of CO adsorption and CO 2 desorption led to disparate reactivity. Supported gold catalysts exhibit very high activity for CO oxidation. However, there is lack of systematic study for supports effect on reactants adsorption and products desorption. Herein, we successfully prepared supported gold catalysts on TiO 2 matrix exposing either {1 0 1} or {0 0 1} crystal plane (labeled as Au/TiO 2 -1 0 1 and Au/TiO 2 -0 0 1 respectively) by deposition-precipitation (DP) method. It is found that the reactivity of Au/TiO 2 -1 0 1 was much higher than Au/TiO 2 -0 0 1 in CO oxidation reaction (9.33 × 10−3 mol CO g Au −1 s−1 vs. 6.23 × 10−4 mol CO g Au −1 s−1 at 30 °C). The gold nanoparticles (∼2 nm) were detected as sole gold species in Au/TiO 2 -1 0 1, while not only gold nanoparticles (∼4 nm) but also clusters (∼1.3 nm) were present in Au/TiO 2 -0 0 1. The difference in gold status induced different CO adsorption situations that CO was more effectively adsorbed on gold nanoparticles in Au/TiO 2 -1 0 1 which existed more Au0 site. Meanwhile, we revealed that the bidentate carbonate, which could either block active sites for the reaction or hinder access of reactants, were adsorbed much more strongly on TiO 2 -0 0 1. While on TiO 2 -1 0 1, bicarbonate was the main surface species which was easier decomposed to form CO 2. Therefore, the differences between Au/TiO 2 -1 0 1 and Au/TiO 2 -0 0 1 in the efficiency of CO adsorption and the ability of CO 2 desorption resulted in disparate reactivity. We reasonably gave the deep insight into the support effect that was intrinsically related to the adsorption and desorption behavior of surface species on the catalyst. [ABSTRACT FROM AUTHOR]

Gelsemium elegans (G.elegans) is a plant of the Loganiaceae family, known for its indole alkaloids, including gelsemine, koumine, and gelsenicine. Gelsemine and koumine are well-studied active alkaloids with low toxicity, valued for their anti-anxiety and analgesic properties. However, gelsenicine, another important alkaloid, remains underexplored due to its high toxicity. This study focuses on evaluating the analgesic properties of gelsenicine and comparing them with gelsemine and koumine. The results indicate that all three alkaloids exhibit robust analgesic properties, with gelsemine, koumine, and gelsenicine showing ED 50 values of 0.82 mg/kg, 0.60 mg/kg, and 8.43 μg/kg, respectively, as assessed by the hot plate method. Notably, the therapeutic dose of gelsenicine was significantly lower than its toxic dose (LD 50 = 0.185 mg/kg). The study also investigated the mechanism of action by analyzing the expression levels of GlyRα3 and Gephyrin. The PGE 2 model group showed decreased expression levels of GlyRα3 and Gephyrin, while groups treated with gelsemine, koumine, and gelsenicine were able to reverse this decrease. These results suggest that gelsenicine effectively alleviates PGE 2 -induced hyperalgesia by upregulating the expression of GlyRα3 and Gephyrin, which are key targets of the Gly receptor pathway. • This study explored the analgesic mechanism of gelsenicine for the first time. • Gelsenicine can significantly relieve the hypersensitivity pain caused by PGE 2. • Gelsenicine did not cause pathological damage to the mouse's spinal cord. • Gelsenicine has the best analgesic effect among the G.elegans alkaloids. [ABSTRACT FROM AUTHOR]

[Display omitted] • A facile photochemical synthetic strategy to support noble metal single atoms onto CeO 2 is developed. • An efficient dechlorination strategy, where the stubborn Cl ions strongly binding to Pt sites are deeply removed from the catalyst, is proposed via photo-deposition. • Surface oxygen on CeO 2 is activated after dechlorination, resulting in enhanced capability of H 2 O dissociation. • The water–gas shift activity is thus promoted. Such strategy shows universality toward different metals, supports and reactions. During regular synthesis, the supported catalysts may suffer from incomplete exposure of metal sites, whose activity may accordingly be limited by the stubborn residues and inert coordination environment. Here we report a photochemical strategy to fabricate promoted Pt-CeO 2 catalysts, where UV-induced deep dechlorination and the following surface oxygen activation are achieved. With a photo-deposition method, the usually neglected stubborn Cl residues are easily removed from Pt-CeO 2. The adjacent oxygen species are activated under UV illumination, whose flexible elimination creates sufficient surface vacancies, resulting in enhanced H 2 O dissociation. The derived catalyst shows excellent performances for the water–gas shift (WGS) reaction. Such strategy shows universality toward different metals, supports and reactions. This work sheds light on the synthesis of robust catalysts, by applying photochemical method for Cl removal and surface oxygen activation. The universal strategy shows great potentials in developing promoted solid catalysts for various heterogeneous reactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thirteen anti-neuroinflammatory compounds were from E. ulmoides Oliv. leaves.. • Triterpenoid ulmoidol significantly inhibited the proinflammatory mediators. • Ulmoidol reduced the expression of inducible iNOS and COX-2. • Ulmoidol significantly inhibited the TLR4/MAPK/NF-κB signaling pathway. • Ulmoidol could prevent the binding of PU.1 protein and DNA. • PU.1 might be a potential ULM target. Chronic neuroinflammation is closely associated with the development of neurodegenerative diseases, including Alzheimer's disease (AD). In the current study, 13 anti-neuroinflammatory compounds were isolated from Eucommia ulmoides Oliv. leaves. Among these compounds, trans -sinapaldehyde (6), 3′,4′,5,7-tetrahydroxy-3-methylflavone (7), and amarusine A (13) were isolated from E. ulmoides leaves for the first time. The ursane-type C 29 -triterpenoid, ulmoidol (ULM, 9), significantly inhibited the production of proinflammatory mediators and reduced the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Moreover, ULM inhibited the cluster of differentiation 14 (CD14)/Toll-like receptor 4 (TLR4) signaling pathway and consequently limited the activation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Notably, electrophoretic mobility shift assay (EMSA) and molecular docking analyses indicated that ULM could prevent PU box binding-1 (PU.1) from binding to DNA, suggesting that PU.1 might be a potential ULM target. In conclusion, ULM alleviates neuroinflammatory responses in microglia, which could be partly explained by its targeting of PU.1 and the resulting suppression of the TLR4/MAPK/NF-κB signaling pathways. These results suggested that ULM may have therapeutic potential as an agent for treating neuroinflammation-related neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Abstract: Manganese oxide (hausmannite) polyhedral nanocrystals were prepared by a microwave-assisted solution-based method using Mn(CH3COO)2 and (CH2)6N4 at 80°C. The as-prepared Mn3O4 nanocrystals were characterized by means of X-ray diffraction, field-emission transmission electron microscopy, field-emission scanning electron microscopy and Raman spectrum. Mn3O4 polyhedral nanocrystals prepared by microwave heating at 80°C for 60min were of cubic and rhombohedral shapes with the edge lengths in the range of 15–40nm. Mn3O4 nanocrystals grew following the Ostwald ripening mechanism with increasing reaction time. High-resolution transmission electron microscopy and selected area electron diffraction confirm that the as-obtained polyhedral nanocrystals were single-crystalline. The magnetic behavior of Mn3O4 nanocrystals was studied. Mn3O4 nanocrystals show an obvious ferromagnetic behavior at low temperatures. The magnetic behavior of Mn3O4 nanocrystals was sensitive to crystal size. Ferromagnetic onset temperatures (T c) of samples 1 and 3 are 40.6 and 41.1K, respectively, lower than that observed for bulk Mn3O4 (42K). [Copyright &y& Elsevier]