• Natural Product Sciences
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• v.24 no.3
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• pp.213-218
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• 2018

Chemical investigation of the plant Tristemma hirtum P. Beauv (Melastomataceae) resulted to the isolation of a new flavonol glycoside named quercetin-7-O-${\alpha}$-D-arabinofuranoside (1), together with nine known compounds including 3'-hexadecanoyl-2'-(9aZ)-tetradecanoyl-glycerol 1'-O-[${\beta}$-D-galactopyranosyl-(1'' ${\rightarrow}$ 6'')-${\alpha}$-D-galactopyranoside] (2), arjunolic acid (3), ${\beta}$-sitosterol-3-O-${\beta}$-D-glucopyranoside (4), terminolic acid (5), quercetin (6), asiatic acid (7), maslinic acid (8), $1{\beta}$-O-galloylpedunculagin (9) and 6-hydroxyapigenin 7-O-${\beta}$-D-glucopyranoside (10) from the methanol extract using normal and reversed phase column chromatography. The structures of these compounds were determined by comprehensive interpretation of their spectral data mainly including 1D- 2D-NMR ($^1H-^1H$ COSY, HSQC, and HMBC) spectroscopic and ESI-TOF-MS mass spectrometric analysis.

• Natural Product Sciences
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• v.6 no.2
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• pp.82-85
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• 2000

The aqueous ethanolic whole plant extract of Rosa arabica was found to contain the new natural dimeric phenolic compound, ellagic acid 3,3'-dimethyl ether $4-O-{\alpha}-rhamnopyranoside$, 9, along with ten known phenolic metabolites (1-8, 10 and 11). Structures of all compounds (1-11) were established by routine methods of analysis and confirmed by FAB-MS, $^1H\;and\;^{13}C$ NMR spectral analysis.

• Natural Product Sciences
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• v.3 no.1
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• pp.8-10
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• 1997

A new flavonol glycoside, quercetin 3-rhamnosyl $(1{\rightarrow}3)$ galactoside [5] was isolated from the leaves of M. africana. The known compounds kaempferol 3-rutinoside [1], 3'-O-methylquercetin 3-rutinoside [2], quercetin 3-rutinoside [3], and quercetin 3-rhamnosyl $(1{\rightarrow}6)$ galactoside [4] were also isolated for the first time from this plant. Their structures were determined by chemical and spectroscopic methods.

• Korean Journal of Pharmacognosy
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• v.20 no.3
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• pp.145-146
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• 1989

A furostanol glycoside, $mp\;190{\sim}198^{\circ}$, was isolated from the MeOH extract of Smilax china rhizomes. The structure was established as a mixture of $26-O-{\beta}-_D-glucopyranosyl-(25R)-22-methoxy-furost-5-en-3\beta,26-diol\;3-O-\alpha-_L-rhamnopyranosyl-(1\rightarrow2)-\beta-_D-glucopyranoside$ and its 22-hydroxy derivative on the basis of spectral data and chemical correlations.

• Korean Journal of Pharmacognosy
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• v.21 no.2
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• pp.148-152
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• 1990

Seven flavonol glycosides from the EtOAc fraction of Ginkgo biloba leaves were identified by high performance liquid chromatography. Separation by reversed phase chromatography on $Lichrosorb^{\circledR}$ RP-18 column was achieved by isocratic elution. The content of the major acylated flavonol glycoside, kaempferol 3-0-[$6'-O-{p}-coumaroyl-{\beta}-_D-glucosyl(1{\rightarrow}2)-{\alpha}-_L-rhamnoside$] was about 8.0% and 0.55% for EtOAc fraction and MeOH extract, respectively.

• Korean Journal of Pharmacognosy
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• v.25 no.2
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• pp.117-120
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• 1994

As part of search for new biologically active substances from marine organism, we have isolated a glyecrol glycoside from the marine red alga Gracilaria verrucosa. The structure of the glycerol glycoside was elucidated as 2-O-${\alpha}-_D$-galactopyranosylglycerol[floridoside(4)] on the basis of spectroscopic and physicochemical evidences.

• 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).

• Archives of Pharmacal Research
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• v.27 no.7
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• pp.727-729
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• 2004

A new cycloartane glycoside was isolated from the dried whole herbs of Camptosorus sibiricus Rupr By means of chemical (hydrolysis) and spectroscopic methods (IR, 1D, and 2D NMR, ESI-MS), the structure was established as $3{\beta}$, $7{\beta}$, $24{\beta}$, 25, 30-pentahydroxycycloartane-3-O-${\beta}$-D-glucopyranoside-24-O-${\beta}$-D-glucopyranoside (1).

• Advances in Traditional Medicine
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• v.9 no.3
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• pp.252-258
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• 2009

Shade-dried flowers of Sarcostemma brevistigma Wight Syn (SBF) belonging to Asclepiadaceae yielded a rare flavonol glycoside viz., Quercetin 5a prenyl, 3-O-glucosyl, 7-O-(4c-p-coumaroyl) neohesperidoside which were characterized based on chemical and spectral (including 2D NMR) studies. The ethyl acetate fraction of alcoholic concentrate (test sample) of flowers of this plant (SBF) was evaluated for its hepatoprotective and inhibition of lipid peroxidation activities to investigate the scientific basis of the traditional uses. The oral administration in varying doses viz., 125 and 250 mg/kg of aqueous suspension of SBF to rats for 7 days produced significant (P < 0.01) hepatoprotective effect comparable to that of standard drug silymarin. The SBF afforded good hepatoprotection against $CCl_4$ induced elevation levels of serum marker enzymes, serum bilirubin and liver weight. The free radical scavenging effects of SBF and flavonol glycoside (SA) were assigned by $Fe^{2+}$/ascorbate induction method (in vitro), which revealed the inhibition of lipid peroxidation. The SBF and SA showed prominent anti-lipid peroxidation activity ($IC_{50}$ about $\sim$180 mg/ml and 11.0 mg/ml respectively), which was comparable to standard drug curcumin ($IC_{50}$ about $\sim$8.25 mg/ml). Thus the hepatoprotective activity of SB could be correlated to the free radical scavenging property of the flavonol glycoside.

• Natural Product Sciences
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• v.17 no.3
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• pp.183-188
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• 2011

A bisdesmosidic cholestane glycoside was isolated from the rhizomes of Polygonatum sibiricum and the structure was elucidated by spectroscopic methods and acid hydrolysis as (22S)-cholest-5-ene-$1{\beta}$,$3{\beta}$,$16{\beta}$,22-tetrol 1-O-${\alpha}$-L-rhamnopyranosyl 16-O-${\beta}$-D-glucopyranoside. This compound exhibited weak cytotoxic activity with the $IC_{50}$ value, $63.6\;{\mu}M$ in human MCF-7 breast cancer line, whereas it failed to show agonistic activity at $100{\mu}M$ in TGR5 assay with Chinese hamster ovary (CHO) cells. This is the first report of a bisdesmosidic cholestane glycoside from Polygonatum species and the full assignments of $^1H$, $^{13}C$ NMR by HMBC, TOCSY and NOESY experiments were provided.