Dalvelutinoside, a new isoflavone glycoside from the methanol extract of <i>Dalbergia velutina</i> roots

<p>A new isoflavone glycoside, dalvelutinoside (<b>1</b>), together with one known isoflavone (<b>2</b>) and five known isoflavone glycosides (<b>3–7</b>) were isolated from the methanol extract of the roots of <i>Dalbergia velutina</i>. Their structures were determined by spectroscopic analysis. All isolated compounds were evaluated for their cytotoxicity against KB and HeLa cell lines.</p

Catomentosaponin, a new triterpene saponin from the roots of <i>Catunaregam tomentosa</i>

<p>A new triterpene saponin, catomentosaponin (<b>1</b>) and 11 known analogues (<b>2</b>–<b>12</b>) were isolated from the roots of <i>Catunaregam tomentosa</i>. The structures of <b>1</b>–<b>12</b> were determined on the basis of extensive NMR and MS data analysis. The sugar residues were identified by co-TLC and HPLC analysis after hydrolysis. All isolated compounds were evaluated for their cytotoxicity against KB and HeLa cell lines. Compound <b>2</b> showed moderate cytotoxicity against KB cell with IC₅₀ value of 24.84 μM.</p

Calaxanthones A-C, three new xanthones from the roots of <i>Calophyllum calaba</i> and the cytotoxicity

<p>Three new xanthones, named calaxanthones A<b>-</b>C (<b>1</b>–<b>3</b>), along with 17 known xanthones (<b>4</b>–<b>20</b>) were isolated from the roots of <i>Calophyllum calaba</i>. Their structures were determined by spectroscopic analysis. All isolated compounds were evaluated for their cytotoxicity against five cancer cell lines (KB, HeLa S-3, HT-29, MCF-7 and HepG-2). Compound <b>3</b> showed potent cytotoxicity against all the five cancer cell lines with IC₅₀ values in the range of 0.82–5.04 μM. Furthermore, compound <b>6</b> showed potent cytotoxicity against KB, HeLa S-3 and HepG2 cells with IC₅₀ values of 7.06, 5.27 and 9.64 μM, respectively. Additionally, compound <b>7</b> showed potent cytotoxicity against KB cell with an IC₅₀ value of 4.62 μM.</p

Calaxanthones A-C, three new xanthones from the roots of <i>Calophyllum calaba</i> and the cytotoxicity

<p>Three new xanthones, named calaxanthones A<b>-</b>C (<b>1</b>–<b>3</b>), along with 17 known xanthones (<b>4</b>–<b>20</b>) were isolated from the roots of <i>Calophyllum calaba</i>. Their structures were determined by spectroscopic analysis. All isolated compounds were evaluated for their cytotoxicity against five cancer cell lines (KB, HeLa S-3, HT-29, MCF-7 and HepG-2). Compound <b>3</b> showed potent cytotoxicity against all the five cancer cell lines with IC₅₀ values in the range of 0.82–5.04 μM. Furthermore, compound <b>6</b> showed potent cytotoxicity against KB, HeLa S-3 and HepG2 cells with IC₅₀ values of 7.06, 5.27 and 9.64 μM, respectively. Additionally, compound <b>7</b> showed potent cytotoxicity against KB cell with an IC₅₀ value of 4.62 μM.</p

Caloinophyllin A, a new chromanone derivative from <i>Calophyllum inophyllum</i> roots

<p>A new chromanone derivative, namely caloinophyllin A (<b>1</b>), along with eight known compounds (<b>2</b>–<b>9</b>), nobiletin (<b>2</b>), pentamethylquercetin (<b>3</b>), 3,5,7,4′-tetramethoxyflavone (<b>4</b>), 5,7,4′-trimethoxyflavone (<b>5</b>), 1,5-dihydroxyxanthone (<b>6</b>), 1,8-dimethoxy-2-hydroxyxanthone (<b>7</b>), 1,6-dihydroxy-7-methoxyxanthone (<b>8</b>) and 4-methoxycaffeic acid (<b>9</b>) were isolated from the roots of <i>Calophyllum inophyllum</i>. The structures of all the isolated compounds (<b>1</b>–<b>9</b>) were fully characterised using spectroscopic data, as well as comparison with the previous literature data. In addition, the quantum chemical calculation has been used to confirm the conformation of <b>1</b>. Moreover, all isolated compounds were assessed for their <i>in vitro</i> cytotoxicity against five human cancer cell lines.</p

Bougainvinones A–H, Peltogynoids from the Stem Bark of Purple Bougainvillea spectabilis and Their Cytotoxic Activity

Eight new peltogynoids, named bougainvinones A–H (<b>1</b>–<b>8</b>), were obtained from the stem bark of Bougainvillea spectabilis. Their structures were elucidated by means of physical data (1D and 2D NMR, HRESIMS) and single-crystal X-ray crystallographic analyses. The peltogynoids, a rare type of modified flavonoids, are reported for the first time from this species of the genus <i>Bougainvillea</i>. All isolated compounds were evaluated for their cytotoxic effects against five cancer cell lines including KB, Hela S-3, HT-29, MCF-7, and HepG2. Among them, compound <b>7</b> showed cytotoxicity against five cancer cell lines with IC₅₀ values in the 7.4–9.7 μM range, and compounds <b>2</b> and <b>3</b> exhibited cytotoxicity against the KB cell line with IC₅₀ values of 6.6 and 9.0 μM

Cytotoxic Cardiac Glycoside Constituents of <i>Vallaris glabra</i> Leaves

Thirteen cardenolide glycosides (<b>1</b>–<b>13</b>) were isolated from the CH₂Cl₂ and MeOH extracts of <i>Vallaris glabra</i> leaves. The structures of the new compounds (<b>2</b>–<b>13</b>) were identified by spectroscopic methods, with the absolute configurations of the sugar moieties determined by acid hydrolysis. All compounds were evaluated for their cytotoxic activity against human cervix adenocarcinoma, lung carcinoma, and colorectal adenocarcinoma cell lines. The two most potent compounds [2′-<i>O</i>-acetylacoschimperoside P (<b>1</b>) and oleandrigenin-3-<i>O</i>-α-l-2′-<i>O</i>-acetylvallaropyranoside (<b>2</b>)] exhibited IC₅₀ values in the range of 0.03–0.07 μM