ABSTRACT
Three new resveratrol oligomers, cotylelophenol C (1) (resveratrol tetramer) and cotylelosides A (2) and B (3) (O-glucosides of resveratrol trimer), together with four known glucosides of resveratrol oligomers (vaticasides A, B, C, D) and piceid, were isolated from an acetone soluble part of stem of Cotylelobium lanceolatum (Dipterocarpaceae). The structures of new compounds were determined by spectral data analysis. The characteristic properties observed in the NMR spectra of 1 were also discussed.
Subject(s)
Ericales/chemistry , Stilbenes/chemistry , Glucosides/chemistry , Glucosides/isolation & purification , Isomerism , Magnetic Resonance Spectroscopy , Models, Molecular , Molecular Conformation , Resveratrol , Spectrometry, Mass, Fast Atom Bombardment , Spectrophotometry, Ultraviolet , Stilbenes/isolation & purification , Structure-Activity RelationshipABSTRACT
Fourteen flavonol glycosides including two new compounds were isolated from the leaves of two Diospyros plants (D. cathayensis and D. rhombifolia). The structures of isolated compounds were determined by spectroscopic analysis. The scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical of the isolated compounds was also investigated.
Subject(s)
Diospyros , Flavonols/isolation & purification , Glycosides/isolation & purification , Flavonols/chemistry , Glycosides/chemistry , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant LeavesABSTRACT
Four new resveratrol derivatives, upunaphenols B (1), C (4), D (5) (resveratrol tetramer) and E (6, resveratrol dimer with a C6-C1 unit), together with nine known resveratrol oligomers and resveratrol were isolated from an acetone soluble part of stem of Upuna borneensis (Dipterocarpaceae). The structures of new compounds were determined by spectral analysis including 1D and 2D NMR experiments.
Subject(s)
Ericales/chemistry , Stilbenes/chemistry , Chromatography, Thin Layer , Magnetic Resonance Spectroscopy , Models, Molecular , Molecular Conformation , Resveratrol , Spectrometry, Mass, Fast Atom Bombardment , Spectrophotometry, UltravioletABSTRACT
Five new resveratrol (=5-[(E)-2-(4-hydroxyphenyl)ethenyl]benzene-1,3-diol) tetramers, upunaphenols H-J (1-3) and trans-(4) and cis-upunaphenol K (5), were isolated from the stem of Upuna borneensis (Dipterocarpaceae). Their structures were elucidated on the basis of 1D- and 2D-NMR as well as FAB-MS data. Compounds 1-3 bear a rare biphenyl bond in their frameworks. Compounds 1 and 2 have an unprecedented nonacyclic fused ring system, and compounds 2 and 3 have symmetrical structures.
Subject(s)
Ericales , Stilbenes/chemistry , Stilbenes/isolation & purification , Molecular Structure , Plant Bark , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Stems , ResveratrolABSTRACT
Four new trimeric stilbene glucosides, mirabilosides C-F (1-4) were isolated from MeOH extract of stem and root of Welwitschia mirabilis (Welwitschiaceae) along with three known stilbenoids, resveratrol (5), gnemonoside B (6), and gnetin G (7). The structures of these compounds were elucidated by spectroscopic methods.
Subject(s)
Glucosides/chemistry , Gnetophyta/chemistry , Stilbenes/chemistry , Molecular Structure , Plant Roots/chemistry , Plant Stems/chemistryABSTRACT
Two new resveratrol (= 5-[(E)-2-(4-hydroxyphenyl)ethenyl]benzene-1,3-diol) trimers, cotylelophenols A (1) and B (2), were isolated from the stem of Cotylelobium lanceolatum (Dipterocarpaceae), together with ten known resveratrol oligomers (3-12). The structures of the isolates were established on the basis of spectroscopic analyses, including a detailed NMR spectroscopic investigation of 1 under different conditions. Compound 1 is the first resveratrol trimer with a rearranged 4-hydroxyphenyl group. Four possible biogenetic pathways towards resveratrol oligomers are proposed (Scheme).
Subject(s)
Ericales/chemistry , Stilbenes/chemistry , Molecular Structure , ResveratrolABSTRACT
Three acetophenone C-glycosides; 2,4,6-trihydroxyacetophenone 3-C-beta-(2'-O-p-hydroxybenzoyl)-glucopyranoside, 2,4,6-trihydroxyacetophenone 3-C-beta-(2'-O-E-coumaroyl)-glucopyranoside, 2,4,6-trihydroxyacetophenone 3-C-beta-(2'-O-E-cinnamoyl)-glucopyranoside, and two resveratrol O-glycosides; piceid 2'-O-p-hydroxybenzoate and, piceid 2'-O-E-ferulate, together with three known compounds were isolated from the acetone soluble part of stem of Upuna borneensis (Dipterocarpaceae). The structures of isolates were determined by spectral analysis including extensive 2D-NMR spectral analyses.
Subject(s)
Acetophenones/chemistry , Ericales/chemistry , Glucosides/chemistry , Chromatography, Agarose , Glucosides/isolation & purification , Magnetic Resonance Spectroscopy , Molecular Structure , Plant Stems/chemistry , Spectrum AnalysisABSTRACT
Three new stilbene oligomers (1-3) were isolated from the stem bark of Vatica pauciflora. The structures of a resveratrol heptamer (pauciflorol D) (1), a resveratrol dimer (pauciflorol E) (2), and an indanone derivative (pauciflorol F) (3) were elucidated by means of spectroscopic data interpretation, especially HMBC and NOESY NMR experiments.
Subject(s)
Ericales/chemistry , Stilbenes/chemistry , Stilbenes/isolation & purification , Indonesia , Models, Molecular , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Plant Bark/chemistry , Resveratrol , StereoisomerismABSTRACT
Four new phenolic derivatives, gnetofurans A-C (1-3) and dihydropinosylvindiol (4), were isolated from a methanol-soluble extract of the stems of Gnetum klossii, together with nine known compounds [gnetifolin F (5), isorhapontigenin, gnetulin, gnetins E and C, latifolol, gnetol, (-)-epsilon-viniferin, and trans-resveratrol]. The structures of the new compounds were determined by spectral data analysis.
Subject(s)
Benzofurans/isolation & purification , Gnetum/chemistry , Benzofurans/chemistry , Indonesia , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Plant Stems/chemistry , StereoisomerismABSTRACT
Four stilbene derivatives, gnemonols K and L (resveratrol trimers), M (isorhapontigenin dimer), and gnemonoside K (glucoside of resveratrol trimer) together with eleven known stilbenoids and a lignan were isolated from the acetone, methanol and 70% methanol soluble parts of the root of Gnetum gnemon (Gnetaceae). The structures of the isolates were determined by spectral analysis. The antioxidant activity of the stilbenoids on lipid peroxide inhibition and super oxide scavenging activity were also investigated.
Subject(s)
Antioxidants/isolation & purification , Free Radical Scavengers/isolation & purification , Gnetum/chemistry , Stilbenes/isolation & purification , Antioxidants/chemistry , Antioxidants/pharmacology , Free Radical Scavengers/chemistry , Free Radical Scavengers/pharmacology , Indonesia , Lipid Peroxides/antagonists & inhibitors , Magnetic Resonance Spectroscopy , Molecular Structure , Plant Roots/chemistry , Stilbenes/chemistry , Stilbenes/pharmacology , Superoxides/chemistryABSTRACT
Three stilbene trimers (gnemonols D, E, F) were isolated from the root of Gnetum gnemon. The structures were determined by spectroscopic analysis. In addition, the antioxidant activity of the compounds on lipid peroxide inhibition and super oxide scavenging activity were also investigated.
Subject(s)
Gnetum/chemistry , Stilbenes/chemistry , Plant Roots/chemistry , Stilbenes/isolation & purificationABSTRACT
An acetone extract of the stem of Gnetum latifolium Blume afforded the stilbene trimer (latifolol) together with five known stilbenoids (gnetin E, gnetin D, gnetin C, (-)epsilon -viniferin and resveratrol). Their structures were elucidated on the basis of spectral evidence, in particular by using 2D NMR methods.
Subject(s)
Gnetum/chemistry , Plant Stems/chemistry , Stilbenes/chemistry , Stilbenes/isolation & purification , Magnetic Resonance Spectroscopy , Molecular StructureABSTRACT
Five new stilbene oligomers (gnemonols A, B and C, gnemonoside E and gnetal) were isolated together with 2b-hydroxyampelopsin F and gnetin E from Gnetum gnemon and G. gnemonoides. The structures of the compounds were elucidated on the basis of spectral evidence.
