Anti-inflammatory Sesquiterpene Derivatives from the Leaves of <i>Tripterygium wilfordii</i>

Twelve new dihydroagarofuran sesquiterpene polyol esters, triptersinines A–L (<b>1</b>–<b>12</b>), and eight known sesquiterpene pyridine alkaloids were isolated from the leaves of <i>Tripterygium wilfordii</i>. Their structures were elucidated on the basis of spectroscopic analyses, including UV, IR, and NMR experiments (¹H–¹H COSY, NOESY, HSQC, and HMBC). Furthermore, in an in vitro bioassay, compounds <b>1</b>, <b>9</b>, <b>11</b>, <b>13</b>, <b>14</b>, and <b>18</b> showed moderate inhibitory effects on nitric oxide production in LPS-induced macrophages at 5 μM; all compounds were inactive when tested against five human cancer cell lines (IC₅₀ values >1 μM)

A,D-<i>seco</i>-Limonoids from the Stems of <i>Clausena emarginata</i>

Twelve new A,D-<i>seco</i>-limonoids, clauemargines A–L (<b>1</b>–<b>12</b>), and three known analogues were isolated from the stems of <i>Clausena emarginata</i>. The absolute configurations of <b>1</b> and <b>5</b> were confirmed by X-ray crystallography and ECD spectroscopy, respectively. Compounds <b>1</b>, <b>2</b>, <b>8</b>–<b>10</b>, and <b>13</b> showed moderate inhibitory effects on LPS-induced NO production (IC₅₀ values < 10 μM)

Lupane Triterpenoids from the Stems of <i>Euonymus carnosus</i>

Fifteen new lupane-type triterpenoids (<b>1</b>–<b>15</b>) and 10 known triterpenoids (<b>16</b>–<b>25</b>) were isolated from the stems of <i>Euonymus carnosus</i>. The structures of the new compounds were elucidated on the basis of spectroscopic analyses, and the absolute configuration of compound <b>1</b> was confirmed by X-ray crystallographic analysis using anomalous scattering of Cu Kα radiation. In addition, the compounds were tested for their cytotoxic activity against five human cancer cell lines and their ability to inhibit LPS-induced nitric oxide production in the murine microglia BV2 cell line. Compound <b>11</b> exhibited moderate cytotoxicity against several human cancer cell lines, and compounds <b>1</b>, <b>2</b>, <b>4</b>, <b>5</b>, <b>20</b>, and <b>25</b> showed neuritis inhibitory activity against microglial inflammation factor, with IC₅₀ values of 7.39, 7.48, 7.80, 3.48, 2.54, and 6.09 μM, respectively

Carbazole Alkaloids from the Stems of <i>Clausena lansium</i>

Ten new carbazole alkaloids, claulansines A–J (<b>1</b>–<b>10</b>), and seven known analogues (<b>11</b>–<b>17</b>) were isolated from the stems of <i>Clausena lansium</i>. Their structures were established on the basis of extensive spectroscopic analyses, and their absolute configurations were determined by CD experiments and computational methods. Screening results indicated that compounds <b>1</b>, <b>6</b>, <b>8</b>–<b>10</b>, <b>13</b>, <b>14</b>, and <b>17</b> showed selective neuroprotective effects at the concentration of 10 μM

Hepatoprotective glycosides from the rhizomes of <i>Imperata cylindrical</i>

<p>Three new C-methylated phenylpropanoid glycosides (<b>1</b>, <b>2</b>), a new 8–4′-oxyneolignan (<b>3</b>), together with two known analogs (<b>4</b>, <b>5</b>), were isolated from the rhizomes of <i>Imperata cylindrical</i> Beauv. var. <i>major</i> (Nees) C. E. Hubb. Their structures were determined by spectroscopic and chemical methods. Compounds <b>1</b>, <b>2</b>, and <b>5</b> (10 μM) exhibited pronounced hepatoprotective activity against <i>N</i>-acetyl-p-aminophenol (APAP)-induced HepG2 cell damage <i>in vitro</i> assays. Furthermore, their antioxidant activities against Fe²⁺-cysteine-induced rat liver microsomal lipid peroxidation and the effects on the secretion of TNF-α in murine peritoneal macrophages (RAW264.7) induced by lipopolysaccharides were evaluated.</p