Macrocyclic Diterpenoids from Euphorbia helioscopia and Their Potential Anti-inflammatory Activity.

Guided by 1H NMR spectroscopic experiments using the aromatic protons as probes, 11 macrocyclic diterpenes (1-11) were isolated from the aerial parts of Euphorbia helioscopia. Their full three-dimensional structures, including absolute configurations, were established unambiguously by spectroscopic analysis and single-crystal X-ray crystallographic experiments. Among the isolated compounds, compound 1 is the third member thus far of a rare class of Euphorbia diterpenes featuring an unusual 5/10 fused ring system, and 2-4 are new jatrophane diterpenes. Based on the NMR data of the jatrophane diterpenes obtained in this study as well as those with crystallographic structures reported in the literature, the correlations of the chemical shifts of the relevant carbons and the configurations of C-2, C-13, and C-14 of their flexible macrocyclic ring were considered. Moreover, the anti-inflammatory activities of 1-11 were investigated by monitoring their inhibitory effects on nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 cells. Compound 1 showed an IC50 of 7.4 ± 0.6 µM, which might be related to the regulation of the NF-κB signaling pathway by suppressing the translocation of the p65 subunit and the consequent reduction of IL-6 and TNF-α secretions.

Stilbene Glycoside Oligomers from the Roots of Polygonum multiflorum.

Five new trans-2,3,5,4'-tetrahydroxystilbene 2-O-ß-d-glucopyranoside (TSG)-based stilbene glycoside oligomers (1-5) were isolated from the roots of Polygonum multiflorum. Their structures were elucidated by comprehensive spectroscopic analyses and chemical evidences. The absolute configurations of 1, 2, 4, and 5 were established by quantum-chemical electronic circular dichroism (ECD) calculations. Putative biosynthetic pathways of 1-5 were proposed using TSG as the key precursor. In addition, compounds 1 (multiflorumiside H) and 3 (multiflorumiside J) exhibited moderate inhibitory activities against NO production in LPS-stimulated RAW264.7 cells.

Antiviral Triketone-Phloroglucinol-Monoterpene Adducts from Callistemon rigidus.

Callistrilones F - K (1 - 6), six new triketone-phloroglucinol-monoterpene hybrids were isolated from the twigs and leaves of Callistemon rigidus. Their structures with absolute configurations were established by a combination analysis of NMR spectra, X-ray diffraction, and electronic circular dichroism (ECD) calculations. Compounds 3 and 4 exhibited moderate inhibitory activities against herpes simplex virus (HSV-1) with IC50 values of 10.00 ± 2.50 and 12.50 ± 1.30 µm, respectively.

New Acetophenone Derivatives from Acronychia oligophlebia and Their Anti-inflammatory and Antioxidant Activities.

Seven new acetophenone derivatives (acroliones A - G, 1 - 7) and three known ones (8 - 10) were isolated from the leaves of Acronychia oligophlebia. Their structures were elucidated based on extensive spectroscopic analyses (IR, UV, HR-ESI-MS, 1D- and 2D-NMR), X-ray diffraction and comparison with literature data. The anti-inflammatory and antioxidant activities of all isolates were evaluated.

Antiviral activity of ethanol extract of Lophatherum gracile against respiratory syncytial virus infection.

ETHNOPHARMACOLOGICAL RELEVANCE: Lophatherum gracile, an important medicinal plant, is used traditionally in the treatment of cough associated with lung heat and inflammation. In this study, an ethanol extract of L. gracile (DZY) was shown to inhibit respiratory syncytial virus (RSV) infection and RSV-induced inflammation in vitro and in vivo. These findings provide a strong and powerful support for the traditional use of L. gracile in the treatment of RSV-related diseases. AIM OF THE STUDY: To determine the anti-RSV activities of DZY and its ingredients, and explore the relationship between RSV infection and inflammation. MATERIALS AND METHODS: DZY was extracted from L. gracile and its major ingredients were determined by high-performance liquid chromatography (HPLC). RSV-infected HEp-2 and RAW264.7 cell models were established to assess the inhibitory effect of DZY on RSV replication and nitric oxide (NO) production in vitro. Three-week-old BALB/c mice challenged intranasally with RSV were used to establish RSV-infected animal mode. The mice were respectively administered DZY at high-, middle-, and low-dose in different groups. The anti-RSV activity of DZY was evaluated by detecting viral load, lung lesion, CD4+ and CD8+ T cell population, and interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ expression in the lung tissue. RESULTS: In HEp-2 cell line, DZY effectively inhibited RSV infection in a dose-dependent manner with IC50 values of 20 µg/mL against RSV (Long strain) and IC50 values of 25 µg/mL against RSV (A2 strain). The anti-RSV activity of DZY was mainly determined by isoorientin, swertiajaponin, 3, 5-di-caffeoylquinic acid, and 3, 4-di-caffeoylquinic acid. Moreover, DZY suppressed NO production induced by RSV in vitro. In vivo, oral administration of DZY significantly reduced the viral load and ameliorated lesions in the lung tissue. A probable antiviral mechanism was mediated by slightly improving the ratio of CD4+/CD8+ T cells and inhibiting the mRNA and protein expression of IL-1ß, TNF-α, and IFN-γ. CONCLUSIONS: (1) DZY exhibits anti-RSV activities both in vitro and in vivo. (2) RSV infection can trigger a series of inflammatory reactions; thus, ameliorating inflammation is helpful to control the course of disease caused by RSV. These findings provide the rationale and scientific evidence behind the extensive use of L. gracile in traditional medicine for the treatment of diseases potentially caused by RSV.

Cajanusflavanols A-C, Three Pairs of Flavonostilbene Enantiomers from Cajanus cajan.

Three pairs of new flavonostilbene enantiomers, cajanusflavanols A-C (1-3), along with their putative biogenetic precursors 4-6, were isolated from Cajanus cajan. Compound 1 possesses an unprecedented carbon skeleton featuring a unique highly functionalized cyclopenta[1,2,3-de]isobenzopyran-1-one tricyclic core. Compounds 2 and 3 are the first examples of methylene-unit-linked flavonostilbenes. Their structures with absolute configurations were elucidated by spectroscopic analyses, X-ray diffraction, and computational calculations. Compounds 1 and 2 exhibited significant in vitro anti-inflammatory activities.