Ninh Thi Ngoc

Pyrrole and furan oligoglycosides from the starfish Asterina batheri and their inhibitory effect on the production of pro-inflammatory cytokines in lipopolysaccharide-stimulated bone marrow-derived dendritic cells.

Three new pyrrole oligoglycosides, astebatheriosides A-C (1-3), and a new furan oligoglycoside, astebatherioside D (4), were isolated from the starfish Asterina batheri by various chromatographic methods. Their structures were elucidated by spectroscopic and chemical methods. Compounds 2, 3, and 4 moderately inhibited IL-12 p40 production in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs) with IC50 values of 36.4, 31.6, and 22.8μM, respectively.

Steroid constituents from the soft coral Sinularia microspiculata

Abstract A methanol extract of the soft coral Sinularia microspiculata revealed five sterols, including two new compounds. Using combined chromatographic and spectroscopic experiments, the new compounds were found to be 7-oxogorgosterol (1) and 16α-hydroxysarcosterol (2). 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, 3 showed weak cytotoxic effects against HL-60 (IC50  =  89.02  ±  9.93 μM) cell line, whereas 5 was weakly active against HL-60 (IC50  =  82.80  ±  13.65 μM) and SK-Mel2 (IC50  =  72.32  ±  1.30 μM) cell lines.

Steroid Constituents from the Soft Coral Sinularia nanolobata

Six steroids (1-6), including the two new compounds 3β,4α-dihydroxyergosta-5,24(28)-diene (1) and 24(S),28-epoxyergost-5-ene-3β,4α-diol (2), were isolated from the methanol extract of the Vietnamese soft coral Sinularia nanolobata. Their structures were elucidated by spectroscopic methods including one and two dimensional (1D- and 2D)-NMR, Fourier transform ion cyclotron resonance (FT-ICR)-MS, and circular dichroism (CD). Compound 2 exhibited moderate cytotoxicity against the acute leukemia (HL-60) cell line with IC50 value of 33.53±4.25 µM and weak effect on the hepatoma cancer (HepG2) and colon adenocarcinoma (SW480) cell lines with IC50 values of 64.35±7.00 and 71.02±4.00 µM, respectively.

Anti-inflammatory tirucallane saponins from Paramignya scandens.

Five new tirucallane saponins, paramignyosides A-E (1-5), were isolated from the water fraction of the Paramignya scandens stem and leaves. Their structures were elucidated on the basis of spectroscopic evidence including high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) and one dimensional (1D)- and 2D-NMR. The effects of isolated compounds on pro-inflammatory cytokines were evaluated by measuring the production of interleukin (IL)-12 p40, IL-6, and tumor necrosis factor-α (TNF-α) in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs). Paramignyoside C (3) exhibited selective and potent inhibitory effect (IC50=5.03±0.19 µM) on the production of IL-12 p40 comparable to that of the positive control, SB203580 (IC50=5.00±0.16 µM). Further studies are required to confirm efficacy in vivo and the mechanism of anti-inflammatory effects.

Sesquiterpene constituents from the soft coral Sinularia nanolobata

Abstract Using various chromatographic separations, four sesquiterpenes (1–4), including two new compounds, nanolobatols A and B (1 and 2), were isolated from the Vietnamese soft coral Sinularia nanolobata. 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.

Cytotoxic Biscembranoids from the Soft Coral Sarcophyton pauciplicatum

Ten biscembranoids (1-10), including the two new compounds sarcophytolides M and N (1 and 2), were isolated from the methanol extract of the Vietnamese soft coral Sarcophyton pauciplicatum. Their structures were elucidated by spectroscopic methods including one dimensional (1D)- and 2D-NMR, high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), and circular dichroism (CD). The in vitro cytotoxic activity of all isolated compounds against a panel of eight human cancer cell lines including HepG2 (hepatoma cancer), HL-60 (acute leukemia), KB (epidermoid carcinoma), LNCaP (prostate cancer), LU-1 (lung cancer), MCF7 (breast cancer), SK-Mel2 (melanoma), and SW480 (colon adenocarcinoma) was evaluated using the sulforhodamine B colorimetric assay. Among the isolated biscembranoids, 1, 3, 4, 7, 9, and 10 exhibited significant cytotoxic effects and may be selected for further studies of their anticancer activity.

Cytotoxic steroids from the Vietnamese gorgonian Verrucella corona

Graphical abstract Figure. No Caption available. HighlightsSeventeen steroids were isolated from the gorgonian Verrucella corona.Seven new compounds were elucidated by spectroscopic methods.Two compounds were firstly isolated from natural source.Structure of the known compound reticulatic acid was revised.Some compounds showed significant cytotoxicity against eight human cancer cell lines. ABSTRACT Using various chromatographic separations, seventeen steroids including seven new compounds, verrucorosteroids A–F (1–6) and verrucorosterone (7), were isolated from the Vietnamese gorgonian Verrucella corona. Their structures were elucidated by spectroscopic analysis, including HR QTOF MS, 1D and 2D NMR. Among isolates, verrucorosterone (7), 5,6&agr;‐epoxy‐3&bgr;‐hydroxy‐(22E)‐ergosta‐8,22‐dien‐7‐one (14), and 5,6&agr;‐epoxy‐3&bgr;‐hydroxy‐(22E)‐ergosta‐8(14),22‐dien‐7‐one (15) showed significant cytotoxicity (IC50 values ranging from 12.32 ± 1.47 to 33.77 ± 1.28 &mgr;M) against eight human cancer cell lines as LNCaP (prostate cancer), HepG2 (hepatoma cancer), KB (epidermoid carcinoma), MCF‐7 (breast cancer), SK‐Mel2 (melanoma), HL‐60 (acute leukemia), LU‐1 (lung cancer), and SW480 (colon adenocarcinoma).

Eudesmane and aromadendrane sesquiterpenoids from the Vietnamese soft coral Sinularia erecta

Abstract Using various chromatographic separations, eight sesquiterpenoids (1–8), including one new compound 3β,5α-dihydroxyeudesma-4(15),11-diene (1), were isolated from the MeOH extract of the Vietnamese soft coral Sinularia erecta. 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 1 exhibited selective cytotoxicity against the A549 cell line with IC50 of 14.79 ± 0.91 μM.

STRUCTURE ELUCIDATION OF FOUR STEROIDS FROM THE SOFT CORAL SINULARIA NANOLOBATA

Four steroids namely 3 β -hydroxyergosta-5,24(28)-diene-7-one ( 1 ), dissesterol ( 2 ), 16 α -hydroxysarcosterol ( 3 ), and sarcophytosterol ( 4 ) were isolated form the soft coral Sinularia nanolobata using various chromatographic methods. Their structures were elucidated by detailed analysis of the 1D and 2D NMR data and comparison with the reported values.

SESQUITERPENOIDS FROM HOMALOMENA PIERREANA ENGL.

Chemical investigation of Homalomena pierreana Engl. resulted in the isolation of six known sesquiterpenoids, namely 1 β,4β,6α-trihydroxyeudesmane ( 1), 1β,4β,7αtrihydroxyeudesmane ( 2), oplodiol (3), bullatantriol (4), homalomenol A ( 5), and oplopanone (6). Their structures were elucidated by 1D and 2D NM R spectral interpretation.