Tetracyclic Diterpenoids with Isomerized Isospongian Skeleton and Labdane Diterpenoids from the Fruits of <i>Amomum kravanh</i>

Four novel diterpenoids, including three tetracyclic diterpenes with isomerized isospongian skeletons, kravanhins A–C (<b>1</b>–<b>3</b>), and kravanhin D (<b>4</b>), and three new labdane diterpenes (<b>5</b>–<b>7</b>) were isolated from the fruits of <i>Amomum kravanh</i>. Compounds <b>1</b>–<b>4</b> had unprecedented isospongian diterpene skeletons with a <i>trans-anti-cis</i> fused tricyclic ring system. The structures of compounds <b>1</b>–<b>7</b> were established on the basis of extensive analysis of NMR spectra, CD, and X-ray crystallography. Compound <b>2</b> showed inhibitory activity on nitric oxide production in lipopolysaccharide-induced RAW264.7 macrophages with an IC₅₀ value of 36.2 μM

Cytotoxic Dammarane-Type Triterpenoids from the Stem Bark of <i>Dysoxylum binecteriferum</i>

Fourteen new dammarane-type triterpenoids (<b>1</b>–<b>14</b>) and 11 known analogues were isolated from the stem bark of <i>Dysoxylum binecteriferum</i>. The absolute configurations were established by comparison with the literature or by Mo₂(OAc)₄-induced electronic circular dichroism data. All isolates were evaluated for their cytotoxicities against three human cancer cell lines as well as their inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW264.7 cells. Compounds <b>4</b> and <b>8</b> displayed moderate cytotoxicities against HepG2 with IC₅₀ values of 6.5 and 8.0 μM, respectively

α‑Glucosidase Inhibitors via Green Pathway: Biotransformation for Bicoumarins Catalyzed by <i>Momordica charantia </i>Peroxidase

Peroxidase extracted from <i>Momordica charantia</i> catalyzed the H₂O₂-dependent oxidative coupling of 7-hydroxy-4-methylcoumarin to form four new dimers (<b>1</b>–<b>4</b>) and two known ones (<b>5</b>, <b>6</b>). The structures, including the absolute configurations of axially chiral compounds, were unambiguously characterized by NMR spectroscopy, online HPLC-CD, and a variety of computational methods. Bioactive experiments demonstrated that compounds <b>1</b> and <b>2</b> had significant inhibitory effects on yeast α-glucosidase, much better than the controls. Noncompetitive binding mode was found by the graphical analysis of steady-state inhibition data. The mechanism of enzymatic inhibition confirmed in some depth that the inhibitors altered the secondary structure of α-glucosidase by decreasing the α-helix and increasing the β-sheet content. In summary, bicoumarins <b>1</b> and <b>2</b> might be exploited as the lead compounds for further research of antidiabetic agents, and this research provided a “green” method to synthesize compounds with the chiral biaryl axis generally calling for multistep reactions in organic chemistry

Phytotoxicity of Lignanamides Isolated from the Seeds of Hyoscyamus niger

Bioassay-guided fractionation of phytotoxic extracts prepared from the seeds of Hyoscyamus niger led to the isolation of three new lignanamides (<b>1</b>–<b>3</b>), along with six known lignanamides (<b>4</b>–<b>9</b>). The structures of the new compounds were determined by spectroscopic methods, including 1D and 2D nuclear magnetic resonance techniques, and high-resolution electrospray ionization mass spectrometry. The bioactivity analysis of the isolated compounds showed that compound <b>3</b> exhibited significant inhibition on the germination and radical elongation of Allium fistulosum at 10^–4 M concentration

Cytotoxic and Anti-inflammatory Triterpenoids from <i>Toona ciliata</i>

Toonaciliatavarins A–H (<b>1</b>–<b>8</b>), including three new protolimonoids (<b>1</b>–<b>3</b>), two new tirucallane-type triterpenoids (<b>4</b> and <b>5</b>), and three new tetranortriterpenoids (<b>6</b>–<b>8</b>), and 10 known compounds were isolated from the stem barks of <i>Toona ciliata Roem.</i> var. <i>henryi</i>. Their structures were identified on the basis of spectroscopic analysis. The absolute configurations of <b>2</b> and <b>8</b> were determined by ECD calculation. The new isolates were evaluated for their cytotoxicities using six human cancer cell lines and also for their inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW264.7 cells. Compounds <b>4</b> and <b>5</b> showed moderate cytotoxicities, and the protolimonoids (<b>1</b>–<b>3</b>) exhibited marked inhibitory effects on LPS-stimulated NO production

Antihyperglycemic Glucosylated Coumaroyltyramine Derivatives from <i>Teucrium viscidum</i>

Eight new glucosylated coumaroyltyramine derivatives, teuvissides A–H (<b>1</b>–<b>8</b>), were isolated from whole plants of <i>Teucrium viscidum</i>. Their structures were elucidated using spectroscopic data and chemical methods. The antihyperglycemic activities of these compounds were evaluated in HepG2 cells and 3T3-L1 adipocytes, and all of the isolates elicited different levels of glucose consumption at a concentration of 2.0 μM. Teuvissides A (<b>1</b>), B (<b>2</b>), and F (<b>6</b>) induced 2.2-, 2.1-, and 2.2-fold changes, respectively, in the levels of glucose consumption in HepG2 cells and 2.5-, 2.1-, and 2.3-fold changes, respectively, in 3T3-L1 adipocytes relative to the basal levels

Data_Sheet_1_Metabolomic Assessment of Acute Cholestatic Injuries Induced by Thioacetamide and by Bile Duct Ligation, and the Protective Effects of Huang-Lian-Jie-Du-Decoction.DOCX

<p>Huang-Lian-Jie-Du-Decoction, a traditional Chinese formula, has been reported to protect liver from various injuries. Two cholestasis models of rats induced by thioacetamide and by bile duct ligation were established and treated with Huang-Lian-Jie-Du-Decoction. Nuclear Magnetic Resonance-based urinary metabolic profiles were analyzed by orthogonal partial least squares discriminant analysis and univariate analysis to excavate differential metabolites associated with the injuries of the two models and the treatment effects of Huang-Lian-Jie-Du-Decoction. The two cholestatic models shared common metabolic features of excessive fatty acid oxidation, insufficient glutathione regeneration and disturbed gut flora, with specific characteristics of inhibited urea cycle and DNA damage in thioacetamide-intoxicated model, and perturbed Kreb's cycle and inhibited branched chain amino acid oxidation in bile duct ligation model. With good treatment effects, Huang-Lian-Jie-Du-Decoction could regain the balance of the disturbed metabolic status common in the two cholestasis injuries, e.g., unbalanced redox system and disturbed gut flora; and perturbed urea cycle in thioacetamide-intoxicated model and energy crisis (disturbed Kreb's cycle and oxidation of branched chain amino acid) in bile duct ligation model, respectively.</p

Two new arylalkenyl <i>α</i>,<i>β</i>-unsaturated <i>δ</i>-lactones with cytotoxic activity from the leaves and twigs of <i>Cryptocarya concinna</i>

<p>Tow new arylalkenyl <i>α</i>,<i>β</i>-unsaturated <i>δ</i>-lactones named cryptoconcatones K (<b>1</b>) and L (<b>2</b>) were obtained from the leaves and twigs of <i>Cryptocarya concinna</i>. Their structures were established on the basis of spectroscopic data (MS, 1D and 2D NMR). Compounds <b>1</b> and <b>2</b> showed cytotoxic activities with IC₅₀ values of 4.5 and 3.9 μM against Huh7 cancer cell line, respectively.</p

Synergistic Antifungal Meroterpenes and Dioxolanone Derivatives from the Endophytic Fungus <i>Guignardia</i> sp.

Nine new meroterpenes (<b>1</b>–<b>9</b>) and one new dioxolanone derivative (<b>10</b>), along with seven known compounds (<b>11</b>–<b>17</b>), were isolated from solid cultures of the endophytic fungus <i>Guignardia</i> sp., obtained from <i>Euphorbia sieboldiana</i>. Their structures were elucidated by analysis of UV, IR, 1D and 2D NMR, and HRESIMS data, and their absolute configurations were determined by a combination of single-crystal X-ray studies, modified Mosher methods, and Rh₂(OCOCF₃)₄- and Mo₂(OCOCH₃)₄-induced electronic circular dichroism experiments. All compounds were evaluated for their inhibitory effects alone and with fluconazole on the growth and biofilms of <i>Candida albicans</i>. At 6.3 μg/mL combined with 0.031 μg/mL of fluconazole, compounds <b>8</b> and <b>16</b> were found to have prominent inhibition on the growth of <i>C. albicans</i> with fractional inhibitory concentration index values of 0.23 and 0.19, respectively. Combined with fluconazole, both of them (40 μg/mL for <b>8</b> and 20 μg/mL for <b>16</b>) could also inhibit <i>C. albicans</i> biofilms and reverse the tolerance of <i>C. albicans</i> biofilms to fluconazole

Structurally diverse triterpenoid alkaloids from <i>Buxus rugulosa</i>

Four new nortriterpenoid alkaloids, namely buxrugulines E–H (1–4), along with five known ones (5–9), were isolated from the twigs and leaves of Buxus rugulosa. Their structures were identified based on extensive NMR data and MS spectroscopic analyses. Our bioassays revealed that compounds 5, 6 and 8 exhibited potent cytotoxicity in vitro against MCF-7 cell lines, with IC50 values ranging from 6.70 to 11.00 μM, respectively.</p