• Proceedings of the Ginseng society Conference
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• 1993.09a
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• pp.74-83
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• 1993

In an attempt toward the synthesis of the difficulty accessible ginseng saponins the four dammarane glycosides identical to the natural $ginsenosides-Rh_2,$ - F2, compound K and chikusetsusaponin - LT8 have been prepared from betulafolienetriol(=dammar-24-ene-$3{\alpha},12{\beta}\;20(S)-triol).\;3-O-{\beta}-D-Glucopyranoside$ of 20(S) - protopanaxadiol $(=ginsenoside-Rh_2)$ have been obtained by the regio - and stereoselective glycosylation of the $12-O-acetyldammar-24-ene-3{\beta},\;12{\beta},$ 20(S)-triol. The 12-ketoderivative of 20(S)-protopanaxadiol has been used as aglycon in synthesis of chikusetsusaponin - LT8. Attempted regio - and stereoselective glycosylation of the less reactive tertiary C - 20 - hydroxyl group in order to synthesize the $20-O-{\beta}-D-glucopyranoside$ of 20(S)-protopanaxadiol(=compound K) using 3, 12 - di - O - acetyldammar - 24 - ene - $3{\beta},12{\beta},20(S)$-trial as aglycon was unsuccessful. Glycosylation of 3, 12 - diketone of betulafolienetriol followed by $NaBH_4$ reduction yielded the $20-O-{\beta}-D-glucopyranoside\;of\;dammar-24-ene-3{\beta},12{\alpha},$ 20(S)-triol, the $12{\alpha}-epimer$ of 20(S) - protopanaxadiol. Moreover, a number of semisynthetic ocotillol - type glucosides, analogs of natural pseudoginsenosides, have been prepared.

• YAKHAK HOEJI
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• v.45 no.4
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• pp.339-346
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• 2001

A new oxygenated monoterpene (4) was isolated from the methanol extract of the aerial part of Erechtites hieracifolia together with six known components, a dimethylheptane (1), three ionone derivatives (2, 3 and 7) and two phenylpropanoids (5 and 6). Their structures were identified by means of physico-chemical and spectral data to be (2E, 5E)-6-hydroxy-2,6-dimethylhepta-2,4-dienal (1), 3(R)-hydroxy-5,6-epoxy-$\beta$-ionone (2), 3(R)-hydroxy-5,6-epoxy-7-ionol (3), (3E, 6E)-3,7-dimethylocta-3,5-dien-1,2,7-triol(4), 2-hydroxy-4-(2-propenyl)phenyl-$\beta$-D-glucopyranoside (5), 2-methoxy-4-(2-propenyl)phenyl -$\beta$-D-glucopyra-noside (6) and (6R, 9R)-3-oxo-$\beta$-ionol-$\alpha$-D -glucopyranoside (7).

• Natural Product Sciences
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• v.11 no.2
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• pp.75-78
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• 2005

A new acetophenone named rumexin $(3-hydroxy-5-methyl-4-O-{\beta}-D-glucopyranosyl\;acetophenone)$ was isolated from methanolic extract of Rumex aquatica together with eight known compounds, $quercetin-3-O-{\beta}-D-glucuropyranoside$, $musizin-8-O-{\beta}-D-glucopyranoside$, $quercetin-3-O-{\alpha}-L-rhamnoside$, $emodin-8-O-{\beta}- D-glucopyranoside$, caffeic acid, $1-O-caffeoyl-{\beta}-D-glucopyranoside$, 1-methyl caffeic acid, $kaempferol-3-O-{\beta}-D-glucuropyranoside$. All of the above compounds were isolated from Rumex aquatica for the first time, and structures of compounds were established by spectroscopic means.

• Archives of Pharmacal Research
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• v.14 no.2
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• pp.143-146
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• 1991

A new synthetic sequence for the chiral lactone moiety of compactin was developed from $\alpha$-D-glucose in 9 steps via simultaneous reductive detosylation and epoxide-ring opening of 2, 3-epoxy-4-tosylate using NaBH_4$ to afford 2, 4-dideoxy sugar as a key intermediate.

• Bulletin of the Korean Chemical Society
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• v.21 no.6
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• pp.562-566
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• 2000

$\beta-D-Mannopyranosyl$ disaccharides have been obtained from the coupling of 4,6-O-benzylidene derivatives of ethylthio $\alpha-D-mannopyranoside$ employing NIS-TfOH promoter. NIS-TfOH promoted couplings of the corresponding ethylthio $\beta-D-glucopyranoside$ and produced $\alpha-D-glucopyranosyl$ disaccharides. IDCP (iodonium dicollidine perchlorate) was inactive toward the 4,6-O-benzylidenated ethylthio glucopyranosyl donor. However,lDCP coupled the 4,6-O-benzylidenated $ethylthio-\beta-D-galactopyranoside$ to give a-D-galactopyranosyl disaccharides.

• Natural Product Sciences
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• v.18 no.2
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• pp.111-115
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• 2012

In the course of screening for antioxidant compounds by measuring the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging effect and superoxide quenching activity, methanol extract of Cyperus flaccidus (Cyperaceae) was found to show potent antioxidant activities. Subsequent activity-guided fractionation of the methanolic extract led to the isolation of ten compounds, kaempferol-3,7-O-${\alpha}$-L-dirhamnopyranoside (1), caffeic acid (2), quercetin-3-O-${\alpha}$-L-rhamnopyranosyl($1{\rightarrow}6$)-${\beta}$-D-glucopyranoside (3), kaempferol-3-O-${\alpha}$-L-rhamnopyranoside (4), quercetin-3-O-${\alpha}$-L-rhamnopyranoside (5), luteoiln-7-O-${\beta}$-D-glucopyranoside (6), kaempferol-3-O-${\alpha}$-L-rhamnopyranosyl($1{\rightarrow}6$)-${\beta}$-D-glucopyranoside (7), luteoiln (8), quercetin (9) and quercetin-3-O-${\beta}$-D-glucuronide (10). Their structures were elucidated by spectroscopic studies. Compounds 1 - 10 were isolated for the first time from this plant. Among them, compounds 2, 8 and 9 showed the significant radical scavenging effects on DPPH, and the potent xanthine-originated superoxide quenching activities.

• Natural Product Sciences
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• v.12 no.3
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• pp.122-124
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• 2006

Three flavonoid glycosides, $kaempferol-3-O-{\alpha}-L-rhamnopyranosyl-(1\;{\rightarrow}\;6)-{\beta}$-D-glucopyranoside$ or kaempferol-3-O-rutinoside (1), $isorhamnetic-3-O-{\alpha}-L-rhamnopyranosyl-(16)-{\beta}-D-glucopyranoside$ or isorhamnetin-3-O-rutinoside (2), and $quercetin-3-O-{\beta}-D-glucopyranosyl-(1 ${\rightarrow}\;2)-{\beta}-L-arabinopyranoside$ 3, the latter one being a new compound, were isolated from the methanolic extract of the aerial parts of Carrichtera annua. Mass spectrometry and 1D and 2D NMR spectroscopy allowed establishing the structure of these compounds.

• Natural Product Sciences
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• v.23 no.1
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• pp.16-20
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• 2017

In a continuing study of the fermented noni (Morinda citrifolia) juice exudates, five compounds, heptanyl $2-O-{\beta}-{\small{D}}-xylofuranosyl-(1{\rightarrow}6)-{\beta}-{\small{D}}-glucopyranoside$ (1), n-butyl ${\beta}-{\small{D}}-glucopyranoside$ (2), (1S)-(3-ethenyl-phenyl)-1,2-ethanediol (3), (2S)-2-hydroxybutanedioic acid (4), and daucosterol (5) were isolated from the buthanol partition of the extract. The structures of the isolates were identified by 1D and 2D NMR, and MS experiments, as well as by comparison of their data with the published values. Among the isolates, compounds 1 - 3 were isolated for the first time from the plant species. The isolated compounds were evaluated for their cancer chemopreventive potential based on their ability to inhibit nitric oxide (NO) production and tumor necrosis factor alpha ($TNF-{\alpha}$)-induced $NF-{\kappa}B$ activity, and quinonone reductase-1 (QR1)-inducing effect.

• Archives of Pharmacal Research
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• v.28 no.11
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• pp.1236-1238
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• 2005

A new phenolic glycoside, ophiopojaponin D (1), together with two known compounds, was isolated from the tubers of a famous traditional Chinese herb-Ophiopogon japonicus Ker-Gawl. The spectroscopic and chemical data revealed their structures to be 3-tetradecyloxy-4­hydroxy-allylbenzene-4-O-$\alpha$-L-rhamnopyranosyl (1$\rightarrow$6)-$\beta$-D-glucopyranoside (1), 3, 4-dihy-droxy-allylbenzene-4-O-$\alpha$-L-rhamnopyranosyl (1$\rightarrow$6)-$\beta$-D-glucopyranoside (2) and L-pyro­glutamic acid (3).

• Biomolecules & Therapeutics
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• v.19 no.3
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• pp.336-341
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• 2011

As part of an ongoing search for natural plants with antioxidant compounds by measuring the radical scavenging effect on 1,1-diphenyl- 2-picrylhydrazyl (DPPH), a total extract of the twigs of Galium spurium L. (Rubiaceae) was found to show potent antioxidant activity. Subsequent activity-guided fractionation of the methanolic extract led to the isolation of nine compounds, asperulosidic acid methyl ester (1), asperuloside (2), caffeic acid (3), kaempferol-3-O-L-rhamnopyranoside (4), quercetin-3-O-[${\alpha}$-Lrhamnopyranosyl($1{\rightarrow}6$)-${\beta}$-D-glucopyranoside] (5), isorhamnetin-3-O-glucopyranoside (6), quercetin-3-O-${\alpha}$-L-rhamnopyranoside (7), kaempferol-3-O-[${\alpha}$-L-rhamnopyranosyl($1{\rightarrow}6$)-${\beta}$-D-glucopyranoside] (8), and quercetin (9). Their structures were elucidated by spectroscopic studies. Compounds 1, 3-8 were isolated for the first time from this plant. Among them, compounds 3 and 9 showed the significant radical scavenging effects on DPPH, and compounds 3 and 7 showed the potent riboflavin originated superoxide quenching activities.