Two new triterpenoid saponins from <i>Ilex cornuta</i>

<div><p>Two new triterpenoid saponins (<b>1</b> and <b>2</b>) were isolated from the stems of <i>Ilex cornuta</i>, along with two known triterpenoids (<b>3</b> and <b>4</b>). The structures of compounds <b>1</b> and <b>2</b> were determined as ursane-12,19-diene-28-oic acid 3β-<i>O</i>-β-d-glucuronopyranoside-6-<i>O</i>-methyl ester (<b>1</b>), 3α,23α-dihydroxy-olean-9(11),12-diene-28-oic acid 28-<i>O</i>-β-d-glucopyranosyl ester (<b>2</b>), on the basis of hydrolysis and spectral evidence, including 1D and 2D NMR and high resolution electrospray ionization mass spectrometry (HR-ESI-MS) analyses. Protective effects of compounds <b>1</b>–<b>4</b> were tested against H₂O₂-induced H9c2 cardiomyocyte injury, and the data showed that all these compounds had no cell-protective effect.</p></div

Copper-Catalyzed C–N Bond Formation/Rearrangement Sequence: Synthesis of 4<i>H</i>‑3,1-Benzoxazin-4-ones

A facile and efficient copper-catalyzed method for the synthesis of 4<i>H</i>-3,1-benzoxazin-4-one derivatives has been developed. This procedure is based on a tandem intramolecular C–N coupling/rearrangement process. This method would provide a new and useful strategy for construction of N-heterocycles

Two triterpenoid glycosides from the roots of <i>Camellia oleifera</i> and their cytotoxic activity

<div><p>Two new triterpenoid saponins, oleiferoside N and oleiferoside O, were isolated from the EtOH extract from the roots of <i>Camellia oleifera</i> C. Abel. Their structures were elucidated as 16α-acetoxy-21β,22α-<i>O</i>-diangeloyloxy-23,28-dihydroxyolean-12-ene 3β-<i>O</i>-β-d-xylopyranosyl-(1 → 3)-α-l-arabinopyranosyl-(1 → 3)-β-d-glucuronopyranoside (<b>1</b>), 16α-acetoxy-21β-<i>O</i>-angeloyloxy-23,28-dihydroxy-22α-<i>O</i>-(2-methylbutanoyloxy)olean-12-ene 3β-<i>O</i>-β-d-xylopyranosyl-(1 → 3)-α-l-arabinopyranosyl-(1 → 3)-β-d-glucuronopyranoside (<b>2</b>), on the basis of spectroscopic analyses (IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR) and acid hydrolysis. Both were characterized to be oleanane-type saponins with sugar moieties linked to C-3 of the aglycone. Cytotoxic activities of two saponins were evaluated against four human tumor cell lines (A549, B16, BEL-7402, and MCF-7) by using the MTT <i>in vitro</i> assay. Compounds <b>1</b> and <b>2</b> showed moderate cytotoxic activities toward the tested cell lines.</p></div

Cu-Mediated Stereoselective [4+2] Annulation between <i>N</i>‑Hydroxybenzimidoyl Cyanide and Norbornene

A Cu-mediated stereoselective [4+2] annulation between <i>N</i>-hydroxybenzimidoyl cyanides and norbornene (NBE) has been developed for the synthesis of 4<i>H</i>-1,2-oxazin-4-ones. The reaction proceeds through sequentially forming C–O/C–C bonds. The advantage of this reaction includes high stereoselectivity, excellent yields, as well as simple and mild reaction conditions. A total of 26 examples are presented along with some control experiments

Antibacterial Prenylated Acylphloroglucinols from <i>Psorothamnus fremontii</i>

Psorothatins A–C (<b>1</b>–<b>3</b>), three antibacterial prenylated acylphloroglucinol derivatives, were isolated from the native American plant <i>Psorothamnus fremontii</i>. They feature an unusual α,β-epoxyketone functionality and a β-hydroxy-α,β-unsaturated ketone structural moiety. The latter forms a pseudo-six-membered heterocyclic ring due to strong intramolecular hydrogen bonding, as indicated by the long-range proton–carbon correlations in the NMR experiments. Psorothatin C (<b>3</b>) was the most active compound against methicillin-resistant <i>Staphylococcus aureus</i> and vancomycin-resistant <i>Enterococcus faecium</i>, with IC₅₀ values in the range 1.4–8.8 μg/mL. The first total synthesis of <b>3</b> described herein permits future access to structural analogues with potentially improved antibacterial activities

Oleiferoside W from the roots of <i>Camellia oleifera</i> C. Abel, inducing cell cycle arrest and apoptosis in A549 cells

<p><i>Camellia oleifera</i> C<i>.</i> Abel has been widely cultivated in China, and a group of bioactive constituents such as triterpeniod saponin have been isolated from <i>C. oleifera</i> C. Abel<i>.</i> In the current study, a new triterpeniod saponin was isolated from the EtOH extract of the roots of <i>C. oleifera</i> C. Abel, named as oleiferoside W, and the cytotoxic properties of oleiferoside W were evaluated in non-small cell lung cancer A549 cells. At the same time the inducing apoptosis, the depolarization of mitochondrial membrane potential (Δψ), the up-regulation of related pro-apoptotic proteins, such as cleaved-PARP, cleaved-caspase-3, and the down-regulation of anti-apoptotic marker Bcl-2/Bax were measured on oleiferoside W. Furthermore, the function, inducing the generation of reactive oxygen species (ROS) and apoptosis, of oleiferoside W could be reversed by N-acetylcysteine (NAC). In conclusion, our findings showed that oleiferoside W induced apoptosis involving mitochondrial pathway and increasing intracellular ROS production in the A549 cells, suggesting that oleiferoside W may have the possibility to be a useful anticancer agent for therapy in lung cancer.</p

Antischistosomal activity of hederacochiside C against <i>Schistosoma japonicum</i> harbored in experimentally infected animals

<p>The present study was undertaken to investigate whether hederacochiside C (HSC) possesses antischistosomal effects and anti-inflammatory response activities in <i>Schistosoma japonicum</i>-infected mice. Different concentrations of HSC were administrated to the mice infected by schistosomula or adult worm by intravenous injection twice a day for five consecutive days. The total worm burden, female worm burden, and the egg burden in liver of mice treated with 400 mg/kg HSC were fewer than those in non-treated ones. Murine immune responses following HSC treatment were investigated using enzyme-linked immunosorbent assays (ELISA). Our results indicated that 200 mg/kg HSC could reduce the expression of IgG, tumor necrosis factor (TNF)-α, interleukin (IL)-4 and IL-17 in comparison to infected group, exhibiting best immunomodulatory effects. In addition, scanning electron microscopical examination revealed that male worms treated with HSC lost their normal surface architecture since its surface showed extensive swelling, erosion, and peeling in tegumental regions. Remarkable amelioration was noticed in histopathological investigations, and 200 mg/kg HSC treatment could reduce the size of granulomatous inflammatory infiltrations in the liver which was reflected in nearly normalization of liver architecture. These results suggested that HSC had potential antischistosomal activity and provided a basis for subsequent experimental.</p