RESUMO
Two new acylated flavonoid glycosides have been isolated from the leaves of Quercus dentata Thunb. On the basis of chemical and spectral data, the structures of the compounds have been elucidated as kaempferol 3-O-(2", 4"-diacetyl-3"-cis-p-coumaroyl-6"-trans-p-coumaroyl)-beta-D-glucopyranoside (1), and kaempferol 3-O-(2"-trans-p-coumaroyl-3", 4"-diacetyl-6"-cisp-coumaroyl)-beta-D-glucopyranoside (2).
Assuntos
Glucosídeos/isolamento & purificação , Quempferóis/isolamento & purificação , Quercus/química , Glucosídeos/química , Quempferóis/química , Folhas de Planta/químicaRESUMO
AIM: To study the alkaline-degradation products of ginsenosides from leaves and stems of Panax quinquefolium L. METHODS: Isolation and purification were carried out on silica gel and HPLC; the structures of chemical constituents were elucidated by spectral analysis. RESULTS: From the alkaline-degradation products, nine compounds were identified as: 20 (S) -protopanaxadiol (I), 20 (S) -dammar-25 (26)-ene-3beta, 12beta, 20-triol (II), 24 (R) -ocotillol (III), 20 (S) -protopanaxatriol (IV), 20 (S) -dammar-25 (26)-ene-3beta, 6alpha, 12beta, 20-tetrol (V), dammar-20 (21), 24-diene-3beta, 12beta-diol (VI), dammar-20(21), 24-diene-3beta, 6alpha, 12beta-triol (VII), 20 (S), 24 (S) -dammar-25 (26) -ene-3beta, 6alpha, 12beta, 20, 24-pentanol (VIII), 20 (S) -dammar-23-ene-25-hydroperoxyl-3beta, 6alpha, 12beta, 20-tetrol (IX). CONCLUSION: The configuration of C20 position of ginsenosides was not changed by alkaline-degradation. The complete assignments of 1H and 13C NMR chemical shifts of four new compounds V, VII, VIII, IX, were acquired by means of 2D NMR spectra. Compound I showed antitumor effect on human colon carcinoma cells in vitro.
Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/patologia , Ginsenosídeos/metabolismo , Panax/química , Sapogeninas/isolamento & purificação , Triterpenos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Ginsenosídeos/isolamento & purificação , Humanos , Conformação Molecular , Estrutura Molecular , Folhas de Planta/química , Caules de Planta/química , Plantas Medicinais/química , Sapogeninas/química , Sapogeninas/farmacologia , Triterpenos/química , Triterpenos/farmacologiaRESUMO
A new biphenyl derivative, 4',5-dimethoxy-3-beta-D-glucopyranosyloxy-4-hydroxy-biphenyl, named kakispyrol (1), has been isolated from the leaves of Diospyros kaki, together with three known compounds, vitexin (2), 2'-O-rhamnosyl vitexin (3) and isorhamnetin-3-O-beta-D-glucopyranoside (4). The structure of compound 1 has been determined on the basis of spectroscopic evidence.
Assuntos
Compostos de Bifenilo/isolamento & purificação , Diospyros/química , Monossacarídeos/isolamento & purificação , Folhas de Planta/química , Compostos de Bifenilo/química , Espectroscopia de Ressonância Magnética , Monossacarídeos/químicaRESUMO
Two new acetyl C-glucoside flavonoids, 8-C-beta-D-(2"-O-acetyl)glucofuranosylapigenin and 3"-O-acetylvitexin, along with four known C-glucoside flavonoids, vitexin, 6"-O-acetylvitexin, 2-O-acetylvitexin, and 2"-O-rhamnosylvitexin were isolated from the leaves of Crataegus pinnatifida Bge. var. major N.E.Br. Their structures were elucidated by spectroscopic means and chemical evidence.
Assuntos
Crataegus/química , Flavonoides/isolamento & purificação , Glucosídeos/isolamento & purificação , Plantas Medicinais/química , China , Flavonoides/química , Glucosídeos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Extratos Vegetais/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria Infravermelho , Espectrofotometria UltravioletaRESUMO
Bioassay-guided fractionation of an active n-BuOH extract of the whole plant of Ixeris sonchifolia, using a cytotoxicity assay, resulted in the isolation of three new triterpenoid saponins, ixeris saponins A (1), B (2), and C (3). On the basis of chemical evidence and extensive spectral studies, their structures were established as echinocystic acid 3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->3)-alpha- L-arabinopyranoside (1), 3-O-[bis[beta-D-glucopyranosyl(1-->2 and 1-->3)-alpha-L-arabinopyranosyl]]echinocystic acid 28-O-beta-D-glucopyranosyl ester (2), and 3- O-[beta-D-glucopyranosyl(1-->3)-beta- D-glucopyranosyl(1-->3)-alpha-L-arabinopyranosyl]-16alpha, 23-dihydroxyolean-12-ene 28-O-beta-D-glucopyranosyl ester (3). Compounds 2 and 3 showed significant cytotoxicity against cancer cell lines A375, L929, and HeLa with IC50 values ranging from 8.83 microM to 15.83 microM, while compound 1 was inactive against these three cell lines.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Asteraceae , Fitoterapia , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Linhagem Celular Tumoral/efeitos dos fármacos , Células HeLa/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Triterpenos/químicaRESUMO
A new compound, 2-(1,4-dihydroxy cyclohexanyl )-acetic acid isolated from the seeds of Forsythia suspensa (Thunb.) Vahl, has been assessed for potent antiviral effect on RSV for the first time in vitro by cell morphology methods. Its structure was elucidated on the basis of spectroscopic evidence (IR, MS, 1H-NMR, 13C-NMR). We have trivially named it Rengynic acid.
