New cytotoxic lignan glycosides from <i>Phyllanthus glaucus</i>

<div><p>During the process of exploring bioactive lead compounds from <i>Phyllanthus</i> species, two new glycosides including an arylnaphthalene lignan, diphyllin 4-<i>O</i>-α-l-arabinopyranosyl-(1 → 3)-α-l-arabinopyranoside (<b>1</b>), and a phenolic compound, 3,4,5-trimethoxybenzyl alcohol 7-<i>O</i>-α-l-arabinofuranosyl-(1 → 6)-β-d-glucopyranoside (<b>2</b>), were isolated from the methanol extract of the whole plants of <i>Phyllanthus</i><i>glaucus</i> Wall. ex Müll. Arg. In addition, 31 known compounds, including 19 lignan derivatives (<b>3</b>–<b>21</b>), four phenylpropanoids (<b>22</b>–<b>25</b>), seven simple phenolics (<b>26</b>–<b>32</b>) and one monoterpenoid (<b>33</b>) were obtained. Their structures were determined on the basis of the HR-ESI-MS, 1D and 2D NMR spectroscopic analysis, and pre-column derivative/chiral HPLC analysis in case of <b>1</b> for the absolute configurations. All these compounds were obtained from <i>P. glaucus</i> for the first time. Moreover, the known lignan glycoside, phyllanthusmin C (<b>5</b>) showed <i>in vitro</i> cytotoxicities against HL-60, MCF-7 and SW480 cells with IC₅₀ values of 9.2 ± 0.2, 19.2 ± 1.7 and 20.5 ± 0.9, respectively.</p></div

A new dimeric stilbene from the lianas of <i>Gnetum parvifolium</i>

<p>A new dimeric stilbene, gnetifolin P (<b>1</b>), was isolated from the lianas of <i>Gnetum parvifolium</i>, together with seven known compounds <b>2</b>–<b>8</b>. The structure of compound <b>1</b> was determined by extensive NMR and HRESIMS data analyses, and quantum chemical calculations. All the compounds were evaluated for their anti-inflammatory activity. Compounds <b>1</b> and <b>6</b> inhibited the expression of IL-1β on LPS induced THP-1 cells with the inhibition rate of 35.78 and 64.67%, respectively, at concentration of 25 μg/mL.</p

Cytotoxic Bisbenzylisoquinoline Alkaloids from <i>Stephania epigaea</i>

Six new bisbenzylisoquinoline alkaloids (<b>1</b>–<b>6</b>) and seven known compounds (<b>8</b>–<b>14</b>) were isolated from the tubers of <i>Stephania epigaea</i>, in addition to the major alkaloid, cepharanthine (<b>7</b>). The structures of <b>1</b>–<b>6</b> were elucidated by combined spectroscopic data analysis and chemical methods, with their configurations determined from their optical rotation values and confirmed using circular dichroism. Compounds <b>1</b>–<b>6</b> belong to the oxyacanthine type of bisbenzylisoquinoline alkaloids and have a rare methylenedioxy substituent. Compound <b>1</b>, a dimer composed of benzylisoquinoline and seco-aristolactam units, represents a new type of bisbenzylisoquinoline alkaloid, while compounds <b>3</b>–<b>6</b> are bisbenzylisoquinoline <i>N</i>-oxides. These compounds were evaluated for their in vitro cytotoxicities against six human cancer cell lines (A-549, ECA109, HL-60, MCF-7, SMMC-7721, and SW480). Cepharanthine (<b>7</b>), the major component of <i>S. epigaea</i>, exhibited cytotoxicity against all of these cancer cell lines except ECA109, while its known analogue, <b>10</b>, displayed cytotoxicity against all six cancer cell lines

Triterpenoids with Promoting Effects on the Differentiation of PC12 Cells from the Steamed Roots of <i>Panax notoginseng</i>

The roots of <i>Panax notoginseng</i>, an important Chinese medicinal plant, have been used traditionally in both the raw and processed forms, due to the different chemical constituents and bioactivities found. Thirty-eight dammarane-type triterpenoid saponins were isolated from the steam-processed roots of <i>P. notoginseng</i>, including 18 new substances, namely, notoginsenosides SP1–SP18 (<b>1</b>–<b>18</b>). The structures of <b>1</b>–<b>18</b> were determined on the basis of spectroscopic analysis and acidic hydrolysis. The absolute configuration of the hydroxy group at C-24 in <b>1</b>–<b>4</b>, <b>19</b>, and <b>20</b> was determined in each case by Mo₂(AcO)₄-induced circular dichroism. The new compounds were found to feature a diversity of highly oxygenated side chains, formed by hydrolysis of the C-20 sugar moiety followed by dehydration, dehydrogenation, epoxidation, hydroxylation, or methoxylation of the main saponins in the raw roots. The new saponins <b>1</b>, <b>2</b>, <b>6</b>–<b>8</b>, <b>14</b>, and <b>17</b> and the known compounds <b>20</b>–<b>27</b> showed promoting effects on the differentiation of PC12 cells, at a concentration of 10 μM