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A new hopan-type triterpenoic peracid, tinctoride A (1), together with three known compounds, zeorin (2), 6β,22-dihydroxyhopane (3), and ergosterol peroxide (4), was isolated from Parmotrema tinctorum (Despr. ex Nyl.) Hale. Their chemical structures were identified by extensive 1D and 2D NMR analysis and high-resolution mass spectroscopy and compared with those reported in the literature. The enzyme inhibitory potential of compounds 1–3 against α-glucosidase was investigated, exhibiting nil to weak inhibitory activity.

Two new cycloartanes, combretanones G and H (1 and 2), were isolated from the leaves of Combretum quadrangulare. Their structures were elucidated by applying a set of spectroscopic methods, while their relative configurations were determined using DFT-NMR chemical shift calculations and subsequent assignment of DP4 probabilities. Compounds 1 and 2 are C-23/C-24 stereoisomers of the previously-reported euphonerin E. Both exhibited moderate cytotoxicity against three human cancer cell lines. Compound 2 was shown to be a potent antiparasitic. Our results confirm the traditional medicinal uses of Combretum quadrangulare in Vietnam.

Bioactive-guided phytochemical investigation of Euphorbia antiquorum L. growing in Vietnam led to the isolation of five ent-atisanes, one seco-ent-atisane, and one lathyrane (ingol-type). The structures were elucidated as ent-1α,3α,16β,17-tetrahydroxyatisane (1), ethyl ent-3,4-seco-4,16β,17-trihydroxyatisane-3-carboxylate (2), ent-atisane-3-oxo-16β,17-acetonide (3), ent-3α-acetoxy-16β,17-dihydroxyatisane (4), ent-16β,17-dihydroxyatisane-3-one (5), calliterpenone (6), and ingol 12-acetate (7). Their chemical structures were unambiguously determined by analysis of one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) and high resolution mass spectrometry, as well as by comparison with literature data. Among them, 1 is a new compound while 2 is an ethylated artifact of ent-3,4-seco-4,16β,17-trihydroxyatisane-3-carboxylic acid, a new compound. Isolates were evaluated for alpha-glucosidase inhibition. Compound 3 showed the most significant inhibitory activity against alpha-glucosidase with an IC50 value of 69.62 µM. Further study on mechanism underlying yeast alpha-glucosidase inhibition indicated that 3 could retard the enzyme function by noncompetitive.

Two new cycloartane glycosides, nervisides I−J, were isolated from Nervilia concolor whole plants. Their structures were unambiguously established by interpretation of their HRESIMS and 1D and 2D NMR data. These cycloartanes comprised a stereogenic center at C-24, the R configuration of which was assigned based on DFT-NMR calculations and the subsequent DP4 probability score. These compounds were tested for cytotoxicity against K562 and MCF-7 tumor cell lines, revealing mild cytotoxic activity.

In Vietnam, Macrosolen tricolor is used for the treatment of bloating, broken bones, cough, diarrhea, diuretic, rheumatism, and laxative effects. The study aimed to identify the in vitro antiproliferation and anti-inflammation of all fractions and purified compounds from the M. tricolor whole plants, as well as the in silico molecular docking of the potentially cytotoxic compounds. As the results, fractions (MTH.I, MTH.II, MTE.I, and MTE.II) strongly demonstrated antiproliferative properties against three tested cells, MDA-MB-231, RD, and HepG2 (IC50 values ranged from 4.00 ± 0.20 to 70.60 ± 1.44 μg/mL), as well as anti-inflammatory effects (IC50 values ranged from 4.45 ± 0.08 to 23.00 ± 1.18 μg/mL), whereas other fractions meaningfully evidenced selective cytotoxicity and/or anti-inflammation. Therefore, the phytochemical compositions of the active fractions were illuminated, leading to the characterization of eighteen compounds. Compounds (3–5) revealed the most cytotoxic effects towards all examined cells (IC50 values ranged from 6.88 ± 0.12 to 71.64 ± 1.17 μM) and the strongest anti-inflammatory properties (IC50 values of 16.30 ± 0.92, 7.31 ± 0.55, and 9.23 ± 0.60 μM, respectively). Compound 11 showed potential cytotoxicity against MDA-MB-231, RD, and HepG2 cells (IC50 values of 24.42 ± 0.28, 20.60 ± 0.25, and 3.20 ± 0.02 μM, respectively). Furthermore, compounds (4, 5, and 11) interacted with the active site of the apoptosis regulator Bcl-2 protein (PDB ID: 2O2F), were comparable to PAC, and were compatible with their anticancer activity. This project suggests that M. tricolor is a good source of natural antiproliferative and anti-inflammatory agents and contributes to understanding the biological activities of Macrosolen species in traditional Vietnamese medicine.

From the leaves ofCleome chelidoniiL.f., two new flavonol glycosides, named cleomesides A (1) and B (2), and four known compounds, quercetin 3-O-β-glucopyranosyl(1 → 2)-α-rhamnoside-7-O-α-rhamnoside (3), ethyl α-galactopyranoside (4), adenine (5) and glycerol monostearate (6), were isolated. The structures of all isolated compounds (1–6) were determined by NMR spectroscopy and mass spectrometry. The data of known compounds (3–6) were further compared with the reported data for these compounds. [ABSTRACT FROM AUTHOR]

The study aims to determine the hepatoprotective effect of n-hexane, ethyl acetate, and methanol extracts of the leaves and stems of two Cleome species against carbon tetrachloride- (CCl4-) induced liver toxicity both in vitro using human hepatoma (HepG2) cells and in vivo in rats as well as the hepatoprotective property of all isolated compounds on HepG2. After 72 h of treatment, at the concentrations of 25, 50, and 100 μg/mL, the methanol of C. chelidonii stems (CCSM) ranged from 18.6% to 20.8%, whereas the methanol of C. chelidonii stems (CVSM) increased from 12.3% to 17.2% cell viability. The results show that CCSM and CVSM significantly expressed in vitro hepaprotective activity on HepG2. Therefore, the animals were daily treated with these extracts at the doses of 15, 30, and 45 mg/kg body weight for 5 days, and CCl4 was injected (2 ml/kg body weight, i.p.) on the 2nd and 3rd days. Levels of aspartate aminotransferase (ALT) and alanine aminotransferase (AST) in the blood were measured and compared to the silymarin control. The treatments with CCSM and CVSM (30, and 45 mg/kg) possessed significant hepatoprotection and were comparable with the activity of silymarin. Further, phytochemical studies of these ones were conducted and led to the identification of eight flavonoids: visconoside A (1), visconoside B (2), quercetin 3-O-β-D-glucopyranoside 7-O-α-L-rhamnopyranoside (3), kaempferol 3-O-β-D-glucopyranoside 7-O-α-L-rhamnopyranoside (4), cleomeside A (5), cleomeside B (6), cleomeside C (7), and quercetin-3-O-[β-D-glucopyranosyl-(1⟶2)]-α-L-rhamnopyranoside 7-O-α-L-rhamnopyranoside (8). Two major flavonoids (1 and 4) displayed significant hepatoprotective property (at the concentration of 100 μM, the prevention percentage values were 66.5% and 74.2%, respectively, compared to the quercetin control, with value of 80.3%).

Phytochemical investigations of the whole plants of Macrosolen bidoupensis Tangane & V.S. Dang, a new species discovered in Viet Nam were conducted and led to the purification of ten compounds, comprising three lupane-type (1-3), three friedelane-type (4-6), and one glutinane-type (7) triterpenoids and three cholestane-type steroids (8-10) using various chromatographic methods. Their structures were characterized by HR-ESI-MS, NMR experiments and comparison with previous literature. Compounds 1, 3 and 5 expressed moderate cytotoxicity against two tested cell lines - MDA-MB-231 and RD (IC50 ranged from 34.19 to 74.25 µM), whereas compounds 4 and 6 exhibited selective cytotoxic activity (IC50 ranged from 29.07 to 45.20 µM). [ABSTRACT FROM AUTHOR]