Bioactive Sesquiterpenoids from the Peeled Stems of <i>Syringa pinnatifolia</i>

Fourteen new sesquiterpenoids, alashanoids A–H (<b>1</b>, <b>2</b>, and <b>4</b>–<b>9</b>), (+)-2,9-humuladien-6-ol-8-one (<b>3b</b>), and five pairs of enantiomers (<b>1</b> and <b>4</b>–<b>7</b>), along with eight known analogues (<b>3a</b> and <b>10</b>–<b>16</b>) were isolated from the stems of <i>Syringa pinnatifolia</i>. The structures were established using IR, UV, MS, and NMR data. The absolute configurations of the new compounds were resolved by X-ray diffraction, a modification of Mosher’s method, and experimental and calculated ECD data analysis. The new sesquiterpenoids represent three skeletons: a rare 2,2,5,9-tetramethylbicyclo[6.3.0]-undecane (<b>1</b>), a humulane-type (<b>2</b>–<b>8</b>), and a caryophyllene-type (<b>9</b>) skeleton. Compounds <b>6a</b>, <b>7</b>, and <b>11</b> showed protective effects against hypoxia-induced injury to H9c2 cells at a concentration of 40 μM, and <b>5</b>–<b>7</b>, <b>11</b>, and <b>13</b> inhibited NO production in LPS-induced RAW264.7 macrophage cells with IC₅₀ values ranging from 13.6 to 70.6 μM. These compounds decreased the TNF-α and IL-6 levels in RAW264.7 cells in a concentration-dependent manner at 20–80 μM

Bioactive Sesquiterpenoids from the Peeled Stems of <i>Syringa pinnatifolia</i>

Fourteen new sesquiterpenoids, alashanoids A–H (<b>1</b>, <b>2</b>, and <b>4</b>–<b>9</b>), (+)-2,9-humuladien-6-ol-8-one (<b>3b</b>), and five pairs of enantiomers (<b>1</b> and <b>4</b>–<b>7</b>), along with eight known analogues (<b>3a</b> and <b>10</b>–<b>16</b>) were isolated from the stems of <i>Syringa pinnatifolia</i>. The structures were established using IR, UV, MS, and NMR data. The absolute configurations of the new compounds were resolved by X-ray diffraction, a modification of Mosher’s method, and experimental and calculated ECD data analysis. The new sesquiterpenoids represent three skeletons: a rare 2,2,5,9-tetramethylbicyclo[6.3.0]-undecane (<b>1</b>), a humulane-type (<b>2</b>–<b>8</b>), and a caryophyllene-type (<b>9</b>) skeleton. Compounds <b>6a</b>, <b>7</b>, and <b>11</b> showed protective effects against hypoxia-induced injury to H9c2 cells at a concentration of 40 μM, and <b>5</b>–<b>7</b>, <b>11</b>, and <b>13</b> inhibited NO production in LPS-induced RAW264.7 macrophage cells with IC₅₀ values ranging from 13.6 to 70.6 μM. These compounds decreased the TNF-α and IL-6 levels in RAW264.7 cells in a concentration-dependent manner at 20–80 μM

Bioactive Sesquiterpenoids from the Peeled Stems of <i>Syringa pinnatifolia</i>

Fourteen new sesquiterpenoids, alashanoids A–H (<b>1</b>, <b>2</b>, and <b>4</b>–<b>9</b>), (+)-2,9-humuladien-6-ol-8-one (<b>3b</b>), and five pairs of enantiomers (<b>1</b> and <b>4</b>–<b>7</b>), along with eight known analogues (<b>3a</b> and <b>10</b>–<b>16</b>) were isolated from the stems of <i>Syringa pinnatifolia</i>. The structures were established using IR, UV, MS, and NMR data. The absolute configurations of the new compounds were resolved by X-ray diffraction, a modification of Mosher’s method, and experimental and calculated ECD data analysis. The new sesquiterpenoids represent three skeletons: a rare 2,2,5,9-tetramethylbicyclo[6.3.0]-undecane (<b>1</b>), a humulane-type (<b>2</b>–<b>8</b>), and a caryophyllene-type (<b>9</b>) skeleton. Compounds <b>6a</b>, <b>7</b>, and <b>11</b> showed protective effects against hypoxia-induced injury to H9c2 cells at a concentration of 40 μM, and <b>5</b>–<b>7</b>, <b>11</b>, and <b>13</b> inhibited NO production in LPS-induced RAW264.7 macrophage cells with IC₅₀ values ranging from 13.6 to 70.6 μM. These compounds decreased the TNF-α and IL-6 levels in RAW264.7 cells in a concentration-dependent manner at 20–80 μM

Bioactive Sesquiterpenoids from the Peeled Stems of <i>Syringa pinnatifolia</i>

Fourteen new sesquiterpenoids, alashanoids A–H (<b>1</b>, <b>2</b>, and <b>4</b>–<b>9</b>), (+)-2,9-humuladien-6-ol-8-one (<b>3b</b>), and five pairs of enantiomers (<b>1</b> and <b>4</b>–<b>7</b>), along with eight known analogues (<b>3a</b> and <b>10</b>–<b>16</b>) were isolated from the stems of <i>Syringa pinnatifolia</i>. The structures were established using IR, UV, MS, and NMR data. The absolute configurations of the new compounds were resolved by X-ray diffraction, a modification of Mosher’s method, and experimental and calculated ECD data analysis. The new sesquiterpenoids represent three skeletons: a rare 2,2,5,9-tetramethylbicyclo[6.3.0]-undecane (<b>1</b>), a humulane-type (<b>2</b>–<b>8</b>), and a caryophyllene-type (<b>9</b>) skeleton. Compounds <b>6a</b>, <b>7</b>, and <b>11</b> showed protective effects against hypoxia-induced injury to H9c2 cells at a concentration of 40 μM, and <b>5</b>–<b>7</b>, <b>11</b>, and <b>13</b> inhibited NO production in LPS-induced RAW264.7 macrophage cells with IC₅₀ values ranging from 13.6 to 70.6 μM. These compounds decreased the TNF-α and IL-6 levels in RAW264.7 cells in a concentration-dependent manner at 20–80 μM