Six New Polyoxygenated Xanthones from Garcinia cowa and Their Neuroprotective Effects on Glutamate-Mediated Hippocampal Neuronal HT22 Cell Death.

Six new polyoxygenated xanthones, garcicowanones F-H (1-3), norcowanol A-B (4-5), and garcinone F (6) along with twelve known compounds 7-18 were obtained from the latex of Garcinia cowa Roxb. ex Choisy. All new compounds have a 1,3,7-trioxygenated or 1,3,6,7-tetraoxygenated xanthone nucleus and differ from majority of xanthones from G.

Chemical Constituents of and Anti-Inflammatory, Cytotoxic, and Apoptotic Activities of Eupatoriopicrin on Cancer Stem Cells.

Thunb. of the plant family Asteraceae is a popular traditional herb in Vietnam. However, its chemical constituents as well as bioactive principles have not been investigated yet.

Methylated Flavonols from J.F.Gmel. and Their Antimicrobial and Antioxidant Activities.

Methylated flavonols form a special group with modulating biological activities in comparison with kaempferol and quercetin. The present study isolated ten compounds including two kaempferol methyl ethers: 5-hydroxy-3,7,4'-trimethoxyflavone (), 3-hydroxy-5,7,4'-trimethoxyflavone (); four quercetin methyl ethers: retusin (5-hydroxy-3,7,3',4'-tetramethoxyflavone) (), 3,5-dihydroxy-7,3',4'-trimethoxyflavone (), 3,4'-dihydroxy-5,7,3'-trimethoxyflavone (), and 3,5,7,3',4'-pentamethoxyflavone (); -sitosterol (); 5-hydroxy-1-(4'-hydroxyphenyl)eicosan-3-one (); -hydroquinone (); and vanillic acid () from the rhizomes and fruit of J.F.

Chemical and biological evaluation on scopadulane-type diterpenoids from Scoparia dulcis of Vietnamese origin.

From the aerial parts of Scoparia dulcis L. (Scrophulariaceae) grown in Vietnam, four scopadulane-type diterpenoids (4-7), of which 7 is new and was given the trivial name scopadulcic acid C, together with nine known compounds were isolated. Their structures were elucidated by spectroscopic analyses.

New neolignans and lignans from Vietnamese medicinal plant Machilus odoratissima NEES.

Four new natural neolignans and lignans, which were given the trivial names odoratisols A-D (1-4), together with (-)-licarin A, kachirachirol B, obovatifol, and machilin-I were isolated from the air-dried bark of the Vietnamese medicinal plant Machilius odoratissima NEES (Lauraceae). Their absolute structures were determined on the basis of spectroscopic analyses including circular dichroism spectra.

Cytotoxic diterpenoids from Vietnamese medicinal plant Croton tonkinensis GAGNEP.

Six new ent-kaurane-type diterpenoids were isolated from the leaves of the endemic Vietnamese medicinal plant Croton tonkinensis GAGNEP. (Euphorbiaceae) together with three known ent-11alpha-acetoxy-7beta,14alpha-dihydroxykaur-16-en-15-one (1), ent-kaur-16-en-15-one 18-oic acid (5) and ent-18-hydroxykaur-16-ene (7). Their structures were determined by spectroscopic analyses to be ent-7beta-acetoxy-11alpha-hydroxykaur-16-en-15-one (2), ent-18-acetoxy-11alpha-hydroxykaur-16-en-15-one (3), ent-11alpha-acetoxykaur-16-en-18-oic acid (4), ent-15alpha,18-dihydroxykaur-16-ene (6), ent-11alpha,18-diacetoxy-7beta-hydroxykaur-16-en-15-one (8), and ent-(16S)-1alpha,14alpha-diacetoxy-7beta-hydroxy-17-methoxykauran-15-one (14).