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1,4-Naphthoquinone (1) and a new coumarin (3) were isolated fromAjania salicifolia, together with two known compounds (2,4). The structures and stereochemistry of new compounds were elucidated using spectroscopic methods. Two compounds exhibited potent ABTS cation radical scavenging activities with IC50values ranging 7.97–8.44 μM. Two quinones (1,2) exhibited moderate cytotoxic activity against the human cancer cell lines (Hela, HepG2, and K562) with IC50values of 11.24–35.15 μMin vitro. This is the first report of naphthoquinone in the genusAjania. [ABSTRACT FROM PUBLISHER]

Abstract: Gold catalysts supported on high surface area CeO2 were synthesized and tested for low temperature formaldehyde oxidation. It was found that the reactivity was greatly enhanced by increasing surface area of the support. Complete conversion of formaldehyde was obtained on a 3.0Au/CeO2-270 catalyst with a surface area of 270m2 g−1 at 50°C, and a conversion of 92.3% was obtained at 37°C over the same catalyst, which made it promising for indoor formaldehyde removal. Detailed characterizations of the catalyst showed that the enhancement could be attributed to two factors. One was that Au species mainly in high oxidation states formed on the high surface area CeO2 resulted in a high degree of HCHO adsorption, as revealed by in situ diffuse reflectance infrared Fourier transform spectroscopy. The other was the high surface area CeO2 provided more oxygen vacancies by the nano effect and the formation of Au x Ce1−x O2−δ solid solution as revealed by Raman spectroscopy, on which oxygen molecules could be transformed to active species for the reaction. [Copyright &y& Elsevier]

Extracts of the aerial parts of Scorzonera divaricata afforded sulfoscorzonin D ( 1 ) and sulfoscorzonin E ( 2 ), two novel pyrrolidine inner salt alkaloids with a sulfated guaiane sesquiterpene lactone nucleus, along with 22 known compounds. Especially, sulfoscorzonin D containing a unusual monoterpene moiety is very rare. The structures of new compounds were established using spectroscopic analysis including one- and two-dimensional NMR and HRESIMS. The cytotoxicities of compounds 1 – 4 and 10 against three tumor cell lines (K562, Hela, and HepG2) were evaluated using the MTT assay. Compounds 2 and 10 exhibited moderate cytotoxic activity. The biological properties of 1 – 3 , 5 – 8 , 10 – 14 , and 16 – 24 , were screened against nine different gram-positive and gram-negative bacteria. Compounds 1 , 5 – 8 , 10 , and 18 , showed potent antibacterial activities. Chemical compounds studied in this article Glucozaluzanin C (PubChem CID: 442320); 1β,4α-dihydroxy-5α,6β,7α,11βH-eudermn-12; 6-olide (CID: 11119093); oleanolic acid (CID: 10494); lup-20(29)-ene-3β,28-diol (CID: 72326); (22 E )-5α,8α-epidioxyergosta-6,22-dien-3β-ol (CID: 5469431); ergosta-3β,5α, 6β-trialcohol (CID: 44558918); stigma-5-en-3- O -β-glucoside (CID: 5742590); vomifoliol (CID: 12444927); trans -caffeic acid (CID: 689043); trans - p -hydroxy coumaric acid (CID: 637542); 4-hydroxy-3-methoxyphenyl ferulate (CID: 11500646); 7,3′,4′-trihydroxyflavonol (CID: 5281614); tricin (ID: 5281702); luteolin (CID: 5280445); diosmetin (CID: 5281612); 5,7-dihydroxy-8-methoxyflavone (CID: 5281703); 5,7-dihydroxy-6-methoxyflavone (CID: 5320315); methyl-3,4-dihydroxy benzoate (CID: 287064); m -hydroxy benzoic acid (CID: 7420); 7-hydroxy-coumarin (CID: 5281426); and scopoletin (CID: 5280460). [ABSTRACT FROM AUTHOR]

Electrochemical reduction of CO 2 to multicarbon (C 2+ ) products with added value represents a promising strategy for achieving a carbon-neutral economy. Precise manipulation of the catalytic interface is imperative to control the catalytic selectivity, particularly toward C 2+ products. In this study, a unique Cu/UIO-Br interface is designed, wherein the Cu(111) plane is co-modified simultaneously by Br and O from UIO-66-Br support. Such Cu/UIO-Br catalytic interface demonstrates a superior Faradaic efficiency of ≈53% for C 2+ products (ethanol/ethylene) and the C 2+ partial current density reached 24.3 mA cm -2 in an H-cell electrolyzer. The kinetic isotopic effect test, in situ attenuated total reflection Fourier transform infrared spectroscopy and density functional theory calculations have been conducted to elucidate the catalytic mechanism. The Br, O co-modification on the Cu(111) interface enhanced the adsorption of CO 2 species. The hydrogen-bond effect from the doped Br atom regulated the kinetic processes of * H species in CO 2 RR and promoted the formation of * COH intermediate. The formed * COH facilitates the * CO- * COH coupling and promotes the C 2+ selectivity finally. This comprehensive investigation not only provides an in-depth study and understanding of the catalytic process but also offers a promising strategy for designing efficient Cu-based catalysts with exceptional C 2+ products., (© 2024 Wiley‐VCH GmbH.)