• Korean Journal of Pharmacognosy
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• v.23 no.1
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• pp.9-13
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• 1992

From the leaves of Polygala japonica, kaempferol (1), astragalin (2), kaempferol $3-O-(6'-O-acetyl)-{\beta}-D-glucopyranoside$ (3) and kaempferol $3,7-di-O-{\beta}-D-glucopyranoside$ (4), have been isolated and characterized by chemical and spectral means.

• Archives of Pharmacal Research
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• v.22 no.1
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• pp.81-85
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• 1999

Nine flavonoids (1-9) were isolated from the leaves of Morus alba (Moraceae). The structures of compounds were determined to be kaempferol-3-O-$\beta$-glucopyranoisde (astragalin, 1) kaempferol-3-O-(6"-O-acetyl)-$\beta$-D-glucopyranoside (2), quercetin-3-O-(6"-O-acetyl)-$\beta$-D-glucopyranoside (3), quercetin-3-O-$\beta$-D-glucopyranoside (4), kaempferol-3-O-$\alpha$-L-rhamnopyranosyl-(1 6)-$\beta$-D-glucopyranoside (5), quercetin-3-O-$\alpha$-L-rhamnopyranosyl-(1 6)-$\beta$-D-glucopyranoside (rutin, 6), quercetin-3-O-$\beta$-D-glucopyranosyl-(1 6)-$\beta$-D-glucopyranoside (7), quercetin-3,7-di-O-$\beta$-D-glucopyranoside (8) and quercetin (9) on th basis of spectroscopic and chemical studies. Compounds 7 and 9 exhibited significant radical scavenging effect on 1,1-diphenyl-2-picryl-hydrazyl radical.

• Natural Product Sciences
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• v.24 no.4
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• pp.259-265
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• 2018

The three flavone glycosides, 4'-O-methylisoscutellarein 7-O-(6'''-O-acetyl)-${\beta}$-D-allopyranosyl(1${\rightarrow}$2)-${\beta}$-D-glucopyranoside (1), isoscutellarein 7-O-(6'''-O-acetyl)-${\beta}$-D-allopyranosyl(1${\rightarrow}$2)-${\beta}$-D-glucopyranoside (3), and isoscutellarein 7-O-${\beta}$-D-allopyranosyl(1${\rightarrow}$2)-${\beta}$-D-glucopyranoside (4) in addition to a flavonol glycoside, kaempferol 3-O-${\beta}$-D-glucopyranoside (astragalin, 2), were isolated from Stachys japonica (Lamiaceae). In cholinesterase inhibition assay, compound 1 significantly inhibited aceylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities ($IC_{50}s$, $39.94{\mu}g/ml$ for AChE and $86.98{\mu}g/ml$ for BChE). The content of isolated compounds were evaluated in this plant extract by HPLC analysis. Our experimental results suggest that the flavonoid glycosides of S. japonica could prevent the memory impairment of Alzheimer's disease.

• Korean Journal of Pharmacognosy
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• v.38 no.3 s.150
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• pp.254-257
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• 2007

The aerial parts of Brassica juncea (Cruciferae) called by brown or oriental mustard have been widely used as a spice in food and also traditional folk medicine as stimulant, diuretic and expectorant agent. And Gatkimchi made of the aerial parts of this plant are very popular in Korea. The aerial parts of this plant was refluxed with MeOH and then fractionationed with $CH_2Cl_2$, EtOAc, n-BuOH and $H_2O$, successively. One higher alcohol compound and three flavonoids were isolated from the EtOAc fraction through silica gel and Sephadex LH-20 column chromatographies. Their structures were elucidated as n-hexacosanol(1), kaempferol(2), isorhamnetin $3-O-{\beta}-D-glucopyranoside(3)$ and isorhamnetin $3-O-(6'-O-acetyl)-{\beta}-D-glucopyranoside(4)$ by comparison of spectral data with those in references. And compounds 1 and 4 were firstly isolated from this plant.