Sesquiterpene constituents from the soft coral <i>Sinularia nanolobata</i>

<p>Using various chromatographic separations, four sesquiterpenes (<b>1</b>–<b>4</b>), including two new compounds, nanolobatols A and B (<b>1</b> and <b>2</b>), were isolated from the Vietnamese soft coral <i>Sinularia nanolobata</i>. Their structures were determined on the basis of spectroscopic data (¹H and ¹³C NMR, HSQC, HMBC, ¹H–¹H COSY, NOESY and FT-ICR-MS) and by comparison with the literature values. The cytotoxic activity of isolated compounds against a panel of eight human cancer cell lines was also evaluated.</p

Steroid constituents from the soft coral <i>Sinularia microspiculata</i>

<p>A methanol extract of the soft coral <i>Sinularia microspiculata</i> revealed five sterols, including two new compounds. Using combined chromatographic and spectroscopic experiments, the new compounds were found to be 7-oxogorgosterol (<b>1</b>) and 16α-hydroxysarcosterol (<b>2</b>). Their structures were determined on the basis of spectroscopic data (¹H and ¹³C NMR, HSQC, HMBC, ¹H-¹H COSY, NOESY, and FT-ICR-MS) and by comparing obtained results to the values indicated in previous studies. Among the isolated compounds, <b>3</b> showed weak cytotoxic effects against HL-60 (IC₅₀ =  89.02  ±  9.93 μM) cell line, whereas <b>5</b> was weakly active against HL-60 (IC₅₀ =  82.80  ±  13.65 μM) and SK-Mel2 (IC₅₀ =  72.32  ±  1.30 μM) cell lines.</p

Polar steroid derivatives from the Vietnamese starfish <i>Astropecten polyacanthus</i>

<p>Five polar steroid derivatives, including one new glycosylated polyhydroxysteroid namely polyacanthoside A (<b>1</b>), were isolated from the water-soluble materials from the MeOH extract of the Vietnamese starfish <i>Astropecten polyacanthus</i> using various chromatographic separations. The structure elucidation was confirmed by spectroscopic experiments such as HR-ESI-MS, 1D and 2D NMR. Among the isolated compounds, (20<i>R</i>,24<i>S</i>)-3<i>β</i>,6<i>α</i>,8,15<i>β</i>,24-pentahydroxy-5<i>α</i>-cholestane (<b>3</b>) showed significant cytotoxic effect against five human cancer cell lines as HepG2, KB, LNCaP, MCF7 and SK-Mel2 with the IC₅₀ values from 18.03 ± 2.63 to 21.59 ± 3.23 μM.</p

sj-docx-1-npx-10.1177_1934578X221134882 - Supplemental material for Sarcokontums A and B, Two New 13,27-Cyclo-Pentacyclic Triterpenes from the Stems and Leaves of <b><i>Sarcosperma kontumense</i></b> Gagnep. ex Aubrév

Supplemental material, sj-docx-1-npx-10.1177_1934578X221134882 for Sarcokontums A and B, Two New 13,27-Cyclo-Pentacyclic Triterpenes from the Stems and Leaves of Sarcosperma kontumense Gagnep. ex Aubrév by Nguyen Quoc Vuong, Vu Van Chien, Nguyen Thi Hue, Pham Thi Hang, Nguyen Hoang Nam, Nguyen Le Tuan, Pham Van Cuong, Duong Thi Hai Yen, Nguyen Xuan Nhiem, Bui Huu Tai and Phan Van Kiem in Natural Product Communications</p

Eudesmane and aromadendrane sesquiterpenoids from the Vietnamese soft coral <i>Sinularia erecta</i>

<p>Using various chromatographic separations, eight sesquiterpenoids (<b>1</b>–<b>8</b>), including one new compound 3<i>β</i>,5<i>α</i>-dihydroxyeudesma-4(15),11-diene (<b>1</b>), were isolated from the MeOH extract of the Vietnamese soft coral <i>Sinularia erecta</i>. The structure elucidation was confirmed by spectroscopic experiments including 1D and 2D NMR and HR-ESI-MS. The cytotoxic activities against three human cancer cell lines (A-549, HeLa and PANC-1) of all isolated compounds were evaluated by MTT-based colorimetric assays. Compound <b>1</b> exhibited selective cytotoxicity against the A549 cell line with IC₅₀ of 14.79 ± 0.91 μM.</p

Anti-inflammatory Asterosaponins from the Starfish <i>Astropecten monacanthus</i>

Four new asterosaponins, astrosteriosides A–D (<b>1</b>–<b>3</b> and <b>5</b>), and two known compounds, psilasteroside (<b>4</b>) and marthasteroside B (<b>6</b>), were isolated from the MeOH extract of the edible Vietnamese starfish <i>Astropecten monacanthus</i>. Their structures were elucidated by chemical and spectroscopic methods including FTICRMS and 1D and 2D NMR experiments. The effects of the extracts and isolated compounds on pro-inflammatory cytokines were evaluated by measuring the production of IL-12 p40, IL-6, and TNF-α in LPS-stimulated bone marrow-derived dendritic cells. Compounds <b>1</b>, <b>5</b>, and <b>6</b> exhibited potent anti-inflammatory activity comparable to that of the positive control. Further studies are required to confirm efficacy <i>in vivo</i> and the mechanism of effects. Such potent anti-inflammatory activities render compounds <b>1</b>, <b>5</b>, and <b>6</b> important materials for further applications including complementary inflammation remedies and/or functional foods and nutraceuticals

Steroid glycosides from the starfish <i>Pentaceraster gracilis</i>

<p>Using combined chromatographic separations, two new steroid glycosides namely pentacerosides A (<b>1</b>) and B (<b>2</b>), and four known compounds were isolated from the methanol extract of the starfish <i>Pentaceraster gracilis</i>. Their structures were determined on the basis of spectroscopic data (¹H and ¹³C NMR, HSQC, HMBC, ¹H-¹H COSY, ROESY, and FT-ICR-MS) and by comparing obtained results to the literature values. Among the isolated compounds, only maculatoside (<b>5</b>) showed significant cytotoxic effect against Hep-G2 (IC₅₀ = 16.75 ± 0.69 μM) and SK-Mel2 (IC₅₀ = 19.44 ± 1.45 μM) cell lines and moderate effect on KB (IC₅₀ = 36.53 ± 0.78 μM), LNCaP (IC₅₀ = 39.75 ± 3.34 μM), and MCF7 (IC₅₀ = 47.34 ± 7.01 μM) cell lines.</p

Two new simple iridoids from the ant-plant <i>Myrmecodia tuberosa</i> and their antimicrobial effects

<p>Six iridoid derivatives (<b>1–6</b>), including two new compounds myrmecodoides A and B (<b>1</b> and <b>2</b>), were isolated from the ant-plant <i>Myrmecodia tuberosa</i>. Their structures were determined on the basis of spectroscopic data (¹H and ¹³C NMR, HSQC, HMBC, ¹H-¹H COSY, NOESY and HR-ESI-MS) and by comparison with the literature values. Among isolates, <b>3</b> and <b>4</b> exhibit weak antibacterial effect against <i>Staphylococcus aureus</i> subsp. <i>aureus</i> with MIC value of 100.0 μg/mL.</p

Macrocyclic <i>bis</i>-quinolizidine alkaloids from <i>Xestospongia muta</i>

<p>A new stereoisomer <i>Meso</i>-araguspongine C together with nine reported macrocyclic <i>bis</i>-quinolizidine alkaloids araguspongines A, C, E, L, N−P, petrosin, and petrosin A were isolated from marine sponge <i>Xestospongia muta</i>. Stereochemistry of <i>meso</i>-araguspongine C (<b>2</b>) and araguspongines N-P (<b>3</b>−<b>5</b>) were established by their NMR data and conformational analyses. Both araguspongine C (<b>1</b>) and <i>meso</i>-araguspongine C (<b>2</b>) exhibited great cytotoxic activity towards HepG-2, HL-60, LU-1, MCF-7, and SK-Mel-2 human cancer cells (IC₅₀ in the range of 0.43–1.02 μM). At a concentration of 20 μM, isolated compounds (<b>1</b>−<b>10</b>) also showed modest inhibitory effects (from 7.6 to 40.8%) on the NO production in LPS activated RAW264.7 macrophages.</p

Asterosaponins and glycosylated polyhydroxysteroids from the starfish <i>Culcita novaeguineae</i> and their cytotoxic activities

<div><p>Using combined chromatographic methods, two asterosaponins (compounds <b>1</b> and <b>2</b>), including a new compound novaeguinoside E (compound <b>1</b>), and six glycosylated polyhydroxysteroids (compounds <b>3</b>–<b>8</b>) were isolated from a methanol extract of the starfish <i>Culcita novaeguineae</i>. Their structures were determined on the basis of spectroscopic data (¹H and ¹³C NMR, HSQC, HMBC, ¹H–¹H COSY, ROESY, and HRESI-MS) and by comparison with the literature values. The new compound <b>1</b> represents the third example of asterosaponins containing the 5α-cholesta-9(1l)-en-3β,6α,20,22-tetraol aglycone. Among isolated compounds, <b>4</b>–<b>7</b> exhibited moderate to weak cytotoxic activities against five human cancer cell lines such as Hep-G2 (hepatoma), KB (epidermoid carcinoma), LNCaP (prostate cancer), MCF7 (breast cancer), and SK-Mel2 (melanoma).</p></div