Two new chemical constituents from the aerial parts of <i>Tripterygium wilfordii</i>

Tripterygium wilfordii has been historically employed as a conventional botanical insecticide and a plant of medicinal significance. A new dihydroagarofuran sesquiterpene (1) and a new acyclic compound (2), along with seven known compounds (3–9), have been isolated from the aerial parts of Tripterygium wilfordii. The identification of the structures of novel compounds were accomplished through comprehensive spectroscopic analyses, encompassing HRESIMS, NMR, UV, IR, and a comparative analysis with spectroscopic data from compounds previously characterised. In in-vitro bioassay, compound 8 exhibited significant inhibitory activity for NO release in LPS-induced RAW 264.7 cells, with an IC50 value of 15.7 μM.</p

Phenolic and flavonoid compounds from the fruit shell of <i>Camellia oleifera</i>

A new phenolic compound oleiphenol (1), and a new dihydrochalcone oleifechalcone (2) along with seven known compounds (3-9) were isolated from the fruit shell of Camellia oleifera Abel. The planar structures of compounds 1 and 2 were determined on the basis of extensive spectroscopic analyses (IR, UV, NMR, and HR-ESI-MS) and comparison with literature data. The absolute configurations of the new structures were determined by ECD calculations and chemical methods. In addition, compounds 1-9 underwent a series of pharmacological activity tests, including cytotoxic, anti-inflammatory, anti-RSV and antioxidant activities.</p

Four Matrine-Based Alkaloids with Antiviral Activities against HBV from the Seeds of Sophora alopecuroides

Four novel matrine-based alkaloids (<b>1</b>–<b>4</b>) were isolated from the seeds of Sophora alopecuroides. Compounds <b>1</b> and <b>2</b> possess unprecedented 6/6/6/4 and 6/5/6/6 ring systems, respectively, while <b>3</b> and <b>4</b> are a pair of stereoisomeric matrine–acetophenone alkaloids with an unusual skeleton. Their structures were elucidated by means of spectroscopic methods and single-crystal X-ray diffraction. Hypothetical biogenetic pathways for <b>1</b>–<b>4</b> are proposed, and their antiviral activities are also discussed

Three new diterpenoids from <i>Croton laui</i> Merr. et Metc

<p>Three new diterpenoids, including one labdane diterpenoid (<b>1</b>) and two cembrane diterpenoids (<b>2</b>–<b>3</b>), were isolated from the aerial parts of <i>Croton laui</i>, along with four known analogues (<b>4</b>–<b>7</b>). Their structures were elucidated by spectroscopic analysis and comparison with literature data. All compounds were evaluated for their cytotoxicity against two tumour cell lines.</p

Drychampones A–C: Three Meroterpenoids from <i>Dryopteris championii</i>

Three novel sesquiterpenoid-based meroterpenoids, drychampones A–C (<b>1</b>–<b>3</b>, respectively), were isolated from <i>Dryopteris championii</i>. Compounds <b>1</b> and <b>3</b> possessed a novel carbon skeleton which was constructed by an 11/6/6 ring system coupled with a pyronone moiety, and <b>1</b>–<b>3</b> were three racemates. Their structures and absolute configurations were elucidated by NMR, MS, and computational methods. The hypothetical biosynthetic pathways of these meroterpenoids and their antibacterial activities were also discussed

Dimeric Matrine-Type Alkaloids from the Roots of <i>Sophora flavescens</i> and Their Anti-Hepatitis B Virus Activities

Six unusual matrine-type alkaloid dimers, flavesines A–F (<b>1–6</b>, respectively), together with three proposed biosynthetic intermediates (<b>7–9</b>) were isolated from the roots of <i>Sophora flavescens</i>. Compounds <b>1–5</b> were the first natural matrine-type alkaloid dimers, and compound <b>6</b> represented an unprecedented dimerization pattern constructed by matrine and (−)-cytisine. Their structures were elucidated by NMR, MS, single-crystal X-ray diffraction, and a chemical method. The hypothetical biogenetic pathways of <b>1–6</b> were also proposed. Compounds <b>1–9</b> exhibited inhibitory activities against hepatitis B virus

Watsonianone A from Rhodomyrtus tomentosa Fruit Attenuates Respiratory-Syncytial-Virus-Induced Inflammation <i>In Vitro</i>

Respiratory syncytial virus (RSV) is one of the most common respiratory pathogens. Immoderate inflammation plays a great role in causing RSV-induced diseases. In the present study, watsonianone A, isolated from the fruit of Rhodomyrtus tomentosa (Ait.) Hassk, was found to show a good inhibitory effect on RSV-induced NO production, with a half-maximal inhibitory concentration of 37.2 ± 1.6 μM. Enzyme-linked immunosorbent assay and fluorescence quantitative polymerase chain reaction analyses indicated that watsonianone A markedly reduced both mRNA and protein levels of tumor necrosis factor α, interleukin 6, and monocyte chemoattractant protein 1 in RSV-infected RAW264.7 cells. Mechanistically, watsonianone A inhibited nuclear factor κB (NF-κB) activation by suppressing IκBα phosphorylation. Further analysis revealed that watsonianone A activated the thioredoxin system and decreased intracellular reactive oxygen species (ROS) levels, which are closely associated with NF-κB activation in RSV-infected cells. These results reveal that watsonianone A can attenuate RSV-induced inflammation via the suppression of ROS-sensitive inflammatory signaling