Antifungal constituents from the stems of Dracaena cambodiana

The stems of Dracaena cambodiana have been investigated for antifungal constituents, resulting in the isolation of a new steroidal saponin dracagenin A (1) together with two known components 25S-namogenin B (2) and spriroconazole A (3). Their structures were elucidated on the basis of extensive spectroscopic analysis including 1D, 2D NMR and ESI MS. The isolated compounds were evaluated for their antifungal activities. 1 and 3 exhibited inhibitory activity against Aspergilus niger at the MICs of 50 mg/ml. No inhibition effects on F. oxysporum, S. cerevisiae and C. albicans have been found for the tested compounds. Interestingly, toxicity of 3 towards several cancer cell lines has been demonstrated. The IC50 of 3 against Hep-2, Lu, and RD are 2.002, 4.727, and 4.029 mg/ml, respectively

Sterols from stems of Momordica cochinchinesis (Lour.) Spreng.

Three known sterols, polypodine B (1), (22E,24R)-24-methylcholesta-2,22-diene-3β,5α,6β-triol (2) and chondrillasterol (3) were isolated from the stems of Momordica cochinchinesis (Lour.) Spreng. Their chemical structures were successfully determined using NMR and ESI-MS analysis as well as in comparison with the reported data. All compounds were reported from Momordica genus for the first time. Keywords. Momordica cochinchinesis, Cucurbitaceae, steroid

Terpenoids from Adiantum emarginatum

From the petroleum ether fraction of the methanolic extract of Adiantum emarginatum Bory, three triterpenoids including tetrahymanol (1), isoadiantol B (2), hydroxyadiantone (3), and a diterpenoid 8,13-epoxy-14-labden-19-oic acid (4) have been isolated. Their structures were deduced from the spectral evidence and on the basis of X-ray diffraction studies

Chemical constituents of Belamcanda chinensis (L.) DC

From the ethyl acetate extract of the rhizomes from Belamcanda chinensis (Iridaceae) five compounds irisflorentin (1), tectorigenin (2), iristectorigenin A (3), irigenin (4), and acetovanillone(5) were isolated. Their structures were elucidated by spectroscopic methods. This is first report of 5 from B. chinensis. Keywords: Belamcanda chinensis, Iridaceae, acetovanillone

Flavonoid glycosides from Viscum album

Using combined chromatographic methods, four flavonoid glycosides, (2S)-homoeriodictyol-7-O-β-D-apiofuranosyl-(1→2)-O-β-D-glucopyranoside (1), (2S)-5-hydroxy-7,3′-dimethoxyflavanone-4′-O-β-D-apiofuranosyl-(1→2)-O-β-D-glucopyranoside (2), homoflavoyadorinin-B (3), and 3′-methoxyapiin (4) were isolated from the methanol extract of the leaves and twigs of Viscum album. Their structures were elucidated by 1D- and 2D-NMR spectra and in comparison with those reported in the literature. Keywords. Viscum album, flavonoid glycoside

Triterpenes and triterpene-glycoside from the leaves of Lawsonia inermis.

From the leaves of  Lawsonia inermis (syn. L. alba), two triterpenes augustic acid (1) and 1b,2a,3a,19a-tetrahydroxy-12-ursen-28-oic acid (2), and a triterpene-glycoside suavissimoside R1 (3) were isolated by using various chromatoghraphies. Their structures were characterized on the basis of the spectroscopic data (1D-NMR, HSQC, HMBC, ESI-MS) in comparison with the literature. This is the first report of 1 - 3 from Lawsonia species. Keywords: Lawsonia inermis, Lythraceae, Triterpene

Prototane-type tripternenes from the Rhizomes of Alisma plantago-aquatica

Three terpenes with Protostane type were isolated from the rhizomes of Alisma plantago-aquatica. The chemical structures of isolated compounds were characterized as 11β,23S,24R,25-tetrahydroxyprotost-13(17)-en-3-one (alisol A, 1), 11β,23S,25-trihydroxyprotost-13(17)-en-3-one-24R-yl acetate (alisol A acetate, 2), and 11β,23S,24S-trihydroxyprotost-13(17),25-dien-3-one (alisol G, 3), by detailed analysis of the 1D- and 2D-NMR spectra such as 1H-, 13C-NMR, DEPT 90, DEPT135, HSQC, HMBC, 1H-1H COSY, and by the Electronspray Ionization (ESI) mass spectrum. This is the first report of alisol G from Alisma plantago-aquatica

Highly oxygenated sterols from the starfish Archaster typicus

Three highly oxygenated sterols named ergost-22-ene-3β,4β,5α,6α,8β,14α,15α,25R,26-nonol, 27-norcholestane-3β,4β,5α,6α,7β,8β,14α,15α,24R-nonol, 27-norcholestane-3β,4β,5α,6α,8β,14α, 15α,24R-octol were isolated from the methanolic extract of the starfish Archaster typicus. Their structures were determined by the physicochemical and spectral data in comparison with the reported literature. This is the first report of these compounds from the Vietnamese starfish Archaster typicus

Study on synthesis of some new derivatives of Malloapelta B isolated from Mallotus apelta

Six new benzopyran derivatives were synthesized by reduction reaction and Michael reaction from malloapelta B. Their structures were determined as 8-(1’-oxo-butyl)-5,7-dimethoxy-2,2-dimethyl-2H-1-benzopyran (2), 8-(1’-oxo-3’(R)-methyl-4’-acetyl-5’-oxo-hexyl)-5,7-dimethoxy-2,2-dimethyl-2H-1-benzopyran (3), 8-(1’-oxo-3’(R)-methyl-4’(S/R)-(methyl fomiate)-5’-oxo-hexyl)-5,7-dimethoxy-2,2-dimethyl-2H-1-benzopyran (4,4’), 8-(1’-oxo-3’(R)-methyl-4’(S/R)-(ethyl formiate)-5’-oxo-hexyl)-5,7-dimethoxy-2,2-dimethyl-2H-1-benzopyran (5,5’) by spectroscopic data, including two-dimensional NMR techniques and ESI spectrum.Keywords: Malloapelta B; Michael reaction; reduction reaction; 5,7-dimethoxy-2,2-dimethyl-2H-1-benzopyran

Saponins isolated from the Vietnamese sea cucumber Stichopus chloronotus.

Using various chromatographic methods, three triterpene saponins neothyonidioside (1), stichoposide D (2), and holothurin B (3), were isolated from the methanol extract of the sea cucumber Stichopus chloronotus. Their structures were elucidated by 1D and 2D-NMR experiments and comparison of their NMR data with reported values. Compound 1 was isolated from S. chloronotus for the first time