• Archives of Pharmacal Research
• /
• v.23 no.2
• /
• pp.159-162
• /
• 2000

A new stilbene diglycoside, piceatannol-3, 4'-O-$\beta$-D-diglucopyranoside (I), together with desoxyrhaponticin (II), emodin-1-O-$\beta$-D-glucopyranoside (III), and physcion-8-O-b-D-gluco-pyranoside (IV), were isolated from the rhizomes of cultivated Korean rhubarb rhizomes(Rheum undulatum), Jong DaeWhang, and the structures of 1-IV were identified on the basis of chemical and spectral evidences.

• Archives of Pharmacal Research
• /
• v.18 no.4
• /
• pp.282-288
• /
• 1995

The sutdies were carried out to evaluate the consituents in the rihzomes of the cultivated Korean Rhubarb (Polygonaceae). From the acetone fraction ofl methanol extract Compound I (1, 8-dihydroxy-3-methyl anthraquinone, chrysophanic acid), Compound II($chrysophanol-8-O-{\beta}-D-glucopyranoside$), Compound III ($emodin-8-O-{\beta}-D-glucopyranoside$) and Compound IV ($aloe-emodin-8-O-{\beta}-D-glucopyranoside$), and from the ether fraction Compound V(1, 8-dihydorxy-3-emthyl-6-methoxy anthraquinone, physcion) and Compound VI (1, 6, 8-thitydroxy-3-emthyl anthrauinone, emodin), and also from the n-buthanol fraction Compound VII ($rhapontigenin-3-O-{\beta}-D-glucopyranoside, rhaponticin$) and Compound VIII ($piceatannol-3'-O-{\beta}-D-glucopyranoside$), were isolated and identified on the basis of their physico-chemical and spectroscopic evidences (UV, IR, H-NMR, C-NMR, EI-MS), respectively.

• Korean Journal of Medicinal Crop Science
• /
• v.13 no.2
• /
• pp.80-84
• /
• 2005

Five known anthraquinones, physcion (1), I-O-methylemodin (2), emodin (3), $physcion-8-O-{\beta},-D-glucopyranoside$ (5), $emodin-8-O-{\beta},-D-glucopyranoside$ (6) and two known stilbenes, trans-resveratrol (4), $trans-resveratrol-3-O-{\beta},-D-glucopyranoside$ (7) were isolated from MeOH extract of Reynoutria sachalinensis (Polygonaceae). All structures were unambiguously established by 1D and 2D NMR and MS data and the compounds were evaluated for their cytotoxicity against L1210, HL-60, BI6F10 tumor cell lines in MTT assay. Among the compounds, trans-resveratrol (4) exhibited significant cytotoxic activity with $IC_{50}$ values of 9.2, 6.7 and $9.8\;{\mu}g/ml$, against the test cell lines respectively, but compounds 1-3 exhibited the moderate cytotoxic activity.

• Natural Product Sciences
• /
• v.14 no.2
• /
• pp.143-146
• /
• 2008

Protein tyrosine phosphatase 1B (PTP1B) is emerging as a potential therapeutic target for the treatment of type-2 diabetes and obesity. To search for new types of PTP1B inhibitors, we have undertaken in vitro enzyme assay for some anthraquinones and stilbenes isolated from plants. Of the anthraquinones tested, physcion (1), 1-O-methylemodin (2), and emodin (3) showed high activities, with $IC_{50}$ values of 7.6, 7.0, and $3.8{\mu}g/mL$, respectively, while the anthraquinone glycosides, physcion-8-O-${\beta}$-D-glucopyranoside (4) and emodin-8- O-${\beta}$-D-glucopyranoside (5), were less active than their aglycones. All the stilbenens (6 - 15) slightly inhibited PTP1B activity at high concentration of $30{\mu}g/mL$. Our findings suggest that the hypoglycemic effect of anthraquinones may be associated with their PTP1B inhibitory activity.

• Archives of Pharmacal Research
• /
• v.28 no.1
• /
• pp.22-27
• /
• 2005

Bioassay-guided fractionation of methanol extract of Reynoutria sachalinensis flower using DPPH assay has led to the isolation of three anthraquinones and three flavonoids. Their structures were identified as emodin (1), emodin-8-O-$\beta$-D-glucopyranoside (2), physcion-8-O-$\beta$-D­glucopyranoside (3), quercetin-3-O-$\alpha$-L-arabinofuranoside (4), quercetin-3-O-$\beta$-D-galactopyra­noside (5), and quercetin-3-O-$\beta$-D-glucuronopyranoside (6) by comparing their physicochemical and spectral data with those published in literatures. All isolated compounds were evaluated for antioxidant activities with free radical 1, 1-diphenyl-2-picrylhydrazyl (DPPH) scavenging, superoxide radical scavenging and $Cu^{2+}$-mediated low density lipoprotein (LDL) oxidation assay. The results demonstrated that three flavonoids, 4, 5, and 6 had remarkable antioxidant activities with the $IC_{50}$ values of 64.3, 54.7, and 46.2${\mu}M$ (DPPH scavenging), the $IC_{50}$ values of 6.0, 6.7, and $4.4{\mu}M$ (superoxide radical scavenging) and the $IC_{50}$ values of 3.8, 3.2, and 5.4${\mu}M$ against LDL oxidation, respectively.