Seven new ent-eudesmane-type sesquiterpenoids (1-7) and six known analogues (8-13) were isolated from the Chinese liverwort Chiloscyphus polyanthus var. rivularis. Their structures were determined from analysis of MS and NMR spectroscopic data and single-crystal X-ray diffraction.
View Article and Find Full Text PDFIn the present study, scapaundulin C (1), a new labdane diterpenoid, and four related known compounds scapaundulin A (2), 5α, 8α, 9α-trihydroxy-13E-labden-12-one (3), 5α, 8α-dihydroxy-13E-labden-12-one (4), and (13S)-15-hydroxylabd-8 (17)-en-19-oic acid (5), were isolated from the Chinese liverwort Scapania undulate (L.) Dum., using column chromatography.
View Article and Find Full Text PDFThree new polyacetylated labdane diterpenoids ptychantins P-R (1-3) and four known compounds (4-7) were isolated from an EtOH extract of the Chinese liverwort Ptychanthus striatus (Lehm. & Lindenb.) Nees.
View Article and Find Full Text PDFBackground: As probiotics, soy oligosaccharides have become popular as healthy foods to reduce disease risk. However, comprehensive information about oligosaccharides in different food legumes is limited.
Results: In this study, eight oligosaccharides were well detected and quantified in different varieties of eight legume species using high-resolution mass spectrometry.
Two new stigmastane-type steroids, stigmasta-5,22E-diene-3β,11α-diol (1) and stigmasta-5,22E-diene-3β,7α,11α-triol (2), together with eight known compounds, were isolated from the resinous exudates of Commiphora mukul. Their structures were established by extensive analysis of their HR-MS, 1D- and 2D-NMR (COSY, HMQC, HMBC and NOESY) spectra. The isolates were evaluated for their antiproliferative activities against four human cancer cell lines.
View Article and Find Full Text PDFUsing D-pinitol (= 3-O-methyl-D-chiro-inositol) as starting material, a concise synthesis of 4/5-deoxy-4/5-nucleobase derivatives 11-19 has been achieved. The key intermediate 9 was obtained in good yield via an epoxidation from mono-methanesulfonate of D-pinitol. The process of opening of the epoxide ring in 9 by nucleobases appeared to be regioselective in presence of 1,8-diazabicyclo[5.
View Article and Find Full Text PDFFour new monoterpene esters, 2alpha,5beta-dihydroxybornane-2-cinnamate (1), 2alpha,5beta-dihydroxybornane-5-acetyl-2-cinnamate (2), 2alpha,5beta-dihydroxybornane-2-p-hydroxycinnamate (3) and 2alpha,5beta-dihydroxy-bornane-2-cis-p-hydroxycinnamate (4), together with a known compound 3,4-dimethoxystyrene (5) were isolated from Chinese liverwort Conocephalum conicum and six known compounds, 5,7-dihydroxycalamenene (6), 7-hydroxycalamenene (7), lunularin (8), riccardin C (9), marchantin C (10) and riccardin D (11) were isolated from Dumortiera hirsuta. Their structures were elucidated by extensive spectral analysis and chemical correlations. Compounds 1 and 8 showed moderate cytotoxicity against human HepG2 cells with IC50 4.
View Article and Find Full Text PDFAim: To isolate polyphenols from grape seeds and to evaluate their antioxidant effects.
Methods: Pure compounds were isolated by using Diaion HP20, Toyopearl HW40 chromatography repeatedly, as well as semi-preparative RP-HPLC, from ethyl acetate extract of grape seeds. IR, MS, NMR, CD, X-Ray crystal diffraction spectral analysis were used to identify the structures.
J Asian Nat Prod Res
September 2004
From Peucedanum praeruptorum, one new khellactone ester (3'R)-O-acetyl-(4'S)-O-angeloylkhellactone (3), as well as four known angular dihydropyranocoumarins (1, 2, 4, 5) have been isolated. On the basis of NMR spectra and X-ray crystallography, their structures were determined. We have elucidated their absolute configuration by either chiral separation of their alkaline hydrolysis products with Rp-18 HPLC eluted with 5% hydroxypropyl-beta-cyclodextrin (beta-HCD) or by measurement of their CD spectra.
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