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Five undescribed sesquiterpenoid dimers, aucklandiolides A-E (1-5), one new sesquiterpenoid glycoside, β-cyclocostunolide-15-β-D-glucopyranoside (6), and seventeen known analogues (7-23) were isolated from the roots of Aucklandia costus. Their structures were elucidated by comprehensive HRESIMS and NMR spectroscopic data analysis, and their configurations were confirmed by the computational calculations of ECD and NMR chemical shifts. Aucklandiolides A and B are the first examples of dimeric sesquiterpenoids with a unique 6/6/6/5/6/6 ring system originated from a proposed Diels-Alder cycloaddition between two eudesmane sesquiterpenoids. Besides, compounds 9-11, 20, and 22 showed significant inhibition of nitric oxide production in LPS-stimulated RAW 264.7 cells at a concentration of 20 μM., Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Amethystoidesic acid ( 1 ), a triterpenoid with an unprecedented 5/6/6/6 tetracyclic skeleton, and six undescribed diterpenoids, amethystoidins A-F ( 2 - 7 ), were isolated from the rhizomes of Isodon amethystoides along with 31 known di- and triterpenoids ( 8 - 38 ). Their structures were fully elucidated via extensive spectroscopic analysis including 1D and 2D NMR, high-resolution electrospray ionization mass spectrometry (HRESIMS), and electronic circular dichroism (ECD) calculations. Compound 1 is the first example of a triterpenoid possessing a rare ring system (5/6/6/6) derived from a contracted A-ring and the 18,19- seco -E-ring of ursolic acid. Compounds 6 , 16 , 21 , 22 , 24 , and 27 significantly inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, which could be partly mediated by the downregulation of LPS-induced inducible nitric oxide synthase (iNOS) protein expression.

Electronic coupling can be used to tailor electronic states and optical properties of the luminophores. Therefore, electronically coupled systems would provide unique properties, which cannot be achieved by individual constituents. Here, electronically coupled gold nanoclusters (AuNCs) were prepared on the basis of organosilane grafting and a sol-gel-derived porous silica template. After prolonged drying, the formed AuNCs@silica composites exhibited red-shifted, line-width-narrowed, deep-red emission with high quantum yields (QYs) of ∼66% due to electronic-coupling-enhanced radiative rates and covalent-bonding-suppressed nonradiative relaxation. Meanwhile, the absorption maximum was slightly blue-shifted, leading to a large Stokes shift. All experimental findings revealed the formation of electronically coupled AuNC aggregates confined inside the nanopores and bonded to silica matrix. The mechanism is distinctly different from conventional aggregation-enhanced emission. Our work would provide great potential to engineer photophysical properties by controlling the packing modes.

Helicobacter pylori infection is a WHO class 1 carcinogenic factor of gastric adenocarcinoma. In the past decades, many studies have demonstrated the increasing trend of antibiotic resistance and pointed out the necessity of new effective treatment. This study was aimed at identifying phytochemicals that can inhibit H. pylori and possibly serve as adjuvant treatments. Here, in silico molecular docking and drug-like properties analyses were performed to identify potential inhibitors of urease, shikimate kinase and aspartate-semialdehyde dehydrogenase. These three enzymes are targets of the treatment of H. pylori . Susceptibility and synergistic testing were performed on the selected phytochemicals and the positive control antibiotic, amoxicillin. The in-silico study revealed that oroxindin, rosmarinic acid and verbascoside are inhibitors of urease, shikimate kinase and aspartate-semialdehyde dehydrogenase, respectively, in which, oroxindin has the highest potency against H. pylori , indicated by a minimum inhibitory concentration (MIC) value of 50 μg/mL. A combination of oroxindin and amoxicillin demonstrated additive effects against H. pylori , as indicated by a fractional inhibitory concentration (FIC) value of 0.75. This study identified phytochemicals that deserve further investigation for the development of adjuvant therapeutic agents to current antibiotics against H. pylori .