• Natural Product Sciences
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• v.13 no.3
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• pp.190-194
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• 2007

Two new flavonoid compounds, 8,8'-bisbaicalein 1 and baicalein-7-O-caffeate 2 along with six known flavonoids, baicalein, chrysin, scutellarein, 6-hydroxyluteolin, 6-methoxyluteolin and baicalein-7-Oglucoside and ${\beta}-sitosterol$ have been isolated from the stem-bark of Oroxylum indicum (Bignoniaceae) and identified on the basis of spectroscopic and chemical studies. 6-Hydroxyluteolin and 6-methoxyluteolin are reported for the first time from this plant.

• Korean Journal of Pharmacognosy
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• v.23 no.4
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• pp.234-239
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• 1992

Seven flavonoid components were isolated from fr. C of Scutellariae radix which showed antagonistic effects against bradykinin(BK). The results indicated that two oxygen functions (either -OH or $-OCH_3$) at 2'- and 6'-positions and/or an oxygen function at 6-position of flavone seemed to be favored for the BK inhibitory activities. Skullcapflavone-II(IV) which contains $6-OCH_3$, 2'-OH and $6-OCH_3$ in the structure was the most active among the flavones tested.

• Archives of Pharmacal Research
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• v.28 no.6
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• pp.652-656
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• 2005

A number of thioflavones has been synthesized and evaluated for their iNOS inhibitory activities. Thiowogonin (6) was obtained from naturally occurring chrysin in 5 steps. Other thioflavones were prepared from the corresponding flavones in a single step by the reaction with Lawesson's reagent. The biological activities of thioflavones were not enhanced by the functional group conversion from carbonyl to thiocarbonyl. Compounds 11 and 13 showed potent. NO inhibitory activity at high concentration (40 uM), leading to the possible development of novel neuroprotective agents based on wogonin.

• YAKHAK HOEJI
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• v.52 no.1
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• pp.85-91
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• 2008

8-Acyl and 8-sulfonylamidowogonin analogues were synthesized as potential anti-inflammatory agents. Nitration of 5,7-dihydroxyflavone (chrysin) followed by methylation of phenol groups and reduction of nitro group yielded 8-aminowogonin analogues. Acylation and sufonylation of 8-aminowogonin followed by demethylation reactions gave the title compunds. The synthesized wogonin analogues showed much reduced inhibitory activity on prostaglandin $E_2\;(PGE_2)$ production.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2001.11a
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• pp.113-113
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• 2001

Stable MCF-7-ERE cells, in which pERE-Luc reporter gene has been stably integrated into the genome of the MCF-7 cells, were used to detect the estrogenic activity of various dietary flavonoids in either pure chemical or mixtures. Estradiol (E2) induced luciferase activity in dose dependent manner and this activity was inhibited by tamoxifen (Tam) concomitant treatment. A large series of flavonoids showed estrogenic activities, corresponding to EC5O values between 0.2 and 9 microM and their mixtures didn't show additive or synergistic effects. And we could find some structure and activity relationship. First, 4-methoxylation and catechol structure decreased estrogenic activities. Second, hydroxylation of 3 position reduced estrogenic effect. Third glycosides of flavonoids showed weak estrogenic activity or no activity. Interestingly, when tested at high concentrations, genistein, kaempferol, biochanin A and chrysin elicited luciferase induction higher than that of the maximum induction by estradiol. And these effects of genistein and kaempferol could not be fully inhibited with tamoxifen

• Archives of Pharmacal Research
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• v.27 no.3
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• pp.278-282
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• 2004

A number of 8-arylflavones have been synthesized as congeners of wogonin and evaluated for their inhibitory activities of $PGE_2$ production. 8-Arylflavones were obtained from commercially available chrysin via two different synthetic pathways. Most 8-arylflavones exhibited much reduced inhibitory activities against COX-2 catalyzed $PGE_2$ production compared to that of wogonin. Functional group replacement at the 8-position of wogonin from methoxy to aryl group caused loss of inhibitory activity. Our present results imply that the functional group at the 8-position of flavones seems to play very important roles for bioactivity.

• Biomolecules & Therapeutics
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• v.6 no.3
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• pp.256-260
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• 1998

-7-o-p-Fluorobenzoylchrysin was synthesized by condensing p-flouorbenzoic acid with chrysin in organic solvent, and its structure was identified by NMR, MS, UV, and IR. We also investigated the physicochemical properties, hypoglycemic effect, and the quantitative analysis method of this compound. The correlation coefficient of calibration curve on this compound was approximately 0.9945 by absorption spectrophotometry and 0.9989 by high perfornance liqid chromatography 7-o-p-Fluorobenzoylchrysin was resolved in 6.014 min by reversed-phase HPLC column with solvents consisting of methanol (80%) and 10mM phosphoric acd. Its blood glucose inhibition rate is 20.7%.

• Biomolecules & Therapeutics
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• v.17 no.1
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• pp.43-46
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• 2009

The immunosuppressive properties of flavonoids were examined for the first time by testing their effects on T-cell-mediated antibody production, using a classical plague-forming cell (PFC) assay in mice. Among the tested flavonoids including naringenin, chrysin, flavonol, galangin, quercetin, morin, myricetin and biochanin A, only quercetin, orally administered at 25 mg/kg, significantly inhibited the number of IgMproducing PFCs induced by sheep red blood cells (SRBC). Interestingly, biochanin A (isoflavone) increased the number of PFCs, suggesting an immunostimulatory effect. The other flavonoids tested did not inhibit or enhance PFC response significantly. Quercetin was also found to show thymus atrophy dose-dependently at 5-500 mg/kg. All these results indicate that quercetin inhibits in vivo antibody production probably by inhibiting T-cell function.

• Archives of Pharmacal Research
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• v.22 no.3
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• pp.309-312
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• 1999

In searching for potent cancer chemopreventive agents from synthetic or natural products, 28 randomly selected flavonoids were screened for inhibitory effects against partially purified aromatase prepared form human placenta. Over 50% of the flavonoids significantly inhibited aromatase activity, with greatest activity being demonstrated with apigenin $(IC_{50}: 0.9{\mu}/mL)$, chrysin $(IC_{50}: 1.1{\mu}/mL)$ , and hesperetin $(IC_{50}:1.0{\mu}/mL)$.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.112.2-112.2
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• 2003

CYP1 enzymes, CYP1A1, CYP1A2 and CYP1B1, are known to bioactivate procarcinogens particularly polyaromatic compounds. Flavonoids are a class of natural compounds that are present in edible plants. Structurally, these compounds are polyphenols with two aromatic rings (A, B) and a heterocycyclic ring (C). We observed the differential inhibition of 5,7-dihydroxyflavones which are different in numbers of B-ring-OH, to the activity of ethoxyresorufin O-deethylase (EROD) in human hepatic microsomes with the IC50 values, ie, 0.57 mM, 1.28 mM, and 3.62 mM, chrysin, apigenin, and Luteolin, respectively. (omitted)