• Archives of Pharmacal Research
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• 제16권4호
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• pp.283-288
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• 1993

Fourteen flavonoids were evaluated for their effects as potential bradykinin (BK) antagonists. The compounds were evaluatd in several in vitro and in vivo (oral administration) systems ; inhibition of BK induced contractions in isolated rat ileum and uterus, antagonistic effects of BK induced plasma extravasation, reduction of acetic acid induced withing nociception and protection from endotoxic shock. Skullcapflavone II (3), baicalein (5), 5-methoxyflavone (11), 6-methoxyflavone (12) and 2'-methoxyflavone (14) showed effects in all the tests although the order of potency were somewhat varied.

• Journal of the Korean Wood Science and Technology
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• 제31권5호
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• pp.49-56
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• 2003

잣나무 목부 에탄올 조추출물로부터 7종의 화합물을 단리하였으며, 기기분석 결과 flavonoids인 5-hydroxy-7-methoxyflavone을 비롯하여 chrysin, pinocembrin, pinobanksin, galangin 그리고 stilbenoids 화합물인 3-hydroxy-5-methoxystilbene과 pinosylvin으로 각각 동정되었다.

• Journal of the Korean Wood Science and Technology
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• 제31권1호
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• pp.1-9
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• 2003

항균활성이 우수한 헛개나무 목부 에탄올 조추출물로부터 7종의 화합물을 단리하였으며, 기기분석 결과 flavonoid인 5-hydroxy-7-methoxyflavone를 비롯하여 5,7-dihydroxyflavone (chrysin), 5,7-dihydroxyflavanone (pinocembrin), 3,5,7-trihydroxyflavanone (pinobanksin), 3,4',5,7-tetrahydroxyflavanone (aromadendrin)과 stilbenoid인 3-hydroxy-5-methoxystilbene과 3,5-dihydroxystilbene (pinosylvin)으로 각각 동정되었다. 이들 단리물질에 대한 항균활성을 조사한 결과 stilbenoid인 3-hydroxy-5-methoxystilbene이 공시균주의 생장을 완전히 저해하여 단리물질 중 활성이 가장 높은 것으로 나타났다. 그 다음이 pinocembrin과 pinosylvin으로 Cryphonectria parasitica, Trametes versicolor, Tyromyces palustris 그리고 Trichoderma viride에 대해 높은 균사생장억제율을 나타내어 활성이 우수한 것으로 나타났다. 그러나, flavonoid인 pinobanksin, 5- hydroxy-7-methoxyflavone, chrysin, 그리고 aromadendrin은 항균활성이 낮은 것으로 나타났다. 이상의 결과, 헛개나무 목부 에탄올 조추출물의 높은 항균활성은 3-hydroxy-5-methoxystilbene과 pinocembrin, 그리고 pinosylvin에서 유래된 것으로 사료되었다.

• Archives of Pharmacal Research
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• 제26권5호
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• pp.345-350
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• 2003

5,7-Dihydroxyflavones and their Ο-methylated flavone analogs were prepared and evaluated their anti-inflammatory activity to decipher the structure-activity relationships. Most of the analogs were achieved from 2,4,6-trihydroxyacetophenone in 4 steps. 5,7-Dihydroxy-4 -methoxyflavone (4c) and 7-hydroxy-4 ,5-dimethoxyflavone(6c) were prepared following a different synthetic pathway. Among the synthetic flavones tested, 5-hydroxy-7-methoxyflavone analogs (3a-3e) showed moderate inhibitory activities of $PGE_2$ production from LPS-induced RAW 264.7 cells.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.245-245
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• 1994

From the active fraction, cytotoxic constituents 1-5 were isolated and identified to be 2(S)-5,7-dihydroxy-8,2'-dimethoxyflavanone (1), wogonin (5,7-dihydroxy-8-methoxyflavone, 2), 5,7-dihydruxy-8,2'-dimethoxyflavone (3), 2(5) -5,7,2'-trihydroxy-8-methoxyflavanone (4), 2(S) - 5,2',5'-trihydroxy-7,8-dimethoxyflavanone (5), respectively, with those of specimens$\^$1-2)/

• 생약학회지
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• 제33권3호통권130호
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• pp.173-176
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• 2002

In search for the plant-derived antioxidant compound, it was found that the EtOAc, BuOH extracts obtained from the leaves parts of Oryza sativa L. which exhibited a significant antioxidant activity from 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical cleavage. Activity-guided fractionation on the basis of the inhibitory activity upon the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical cleavage. and repeated column chromatography afforded several antioxidant compounds from Oryza sativa L. The structures and stereochemistry of these compounds were established on the basis of analysis of spectra and some chemical transformations as follows: 5,7-dihydroxy- 8-methoxyflavone, $acacetin-7-O-{\beta}-rutinoside$, $pectolinarigenin-7-O-{\beta}-rutinoside$. At antioxidant activity test for isolated three compounds, antioxidant activity was showed too.

• Archives of Pharmacal Research
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• 제18권6호
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• pp.440-448
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• 1995

Fitty two flavones were synthesized from polyoxygenated dibenzoylmethanes which were obtained by a modified Baker-Venkatarman rearrangement, of 2-benzoyl oxyacetophenones. The following flavones among them showed good cytotoxic activities against L1210 and HL60 cells ; 2'-benzoyloxy-5,7-dimethoxyflavone $(8.2{\mu}g/ml,{\;}5.0 {\mu}g/ml)$, 2'-benzyloxy-5,7,8-trimethoxyflavone $(5,9 {\mu}g/ml,{\;}11.0{\mu}g/ml,{\;}2.7{\mu}g/ml)$, 2'-hydroxy-5,7,8-trimethoxyflavone $(9.8{\mu}/ml,{\;}6.2{\mu}g/ml)$, 2'-benzyloxy-5-hydroxyflavone $(5.2 {\mu}g/ml,{\;}3.6{\mu}g/ml)$, and 5,2'-dihydroxyflavone $(5.1{\mu}g/ml,{\;}4.0{\mu}g/ml)$. Presence of 5-methoxy group potentiated the cytotoxic activity, while the existence of 7-methoxy group decreased the activity. 5-Hydroxy or methoxy activates 4-carbonyl group, while 7-methoxy group deactivates the acrbonyl group. From these observation it was concluded that the activation of carbonyl group at C-4 of a flavone is important for the enahncement of the cytotoxic activity. The presence of both 5-hydroxy and 2-benzyloxy-or 2-hydroxy group enhanced the antitumor activity; 2'-benzyloxy-5-hydroxy-7-methoxyflaone 9T/C=144%), 5.2'-dihydroxy-7-methoxyflavone (T/C=132%) and 5,2'-dihydroxy-6,78,6' trtramethoxyflvone (T/C = 172%) 2'hexanolytion of 5,2'-dihydroxy-flavones did not improve the natitumor activity; 2' hexanoyloxy-5-hydroxy-7-methoxyflavone showed T/C = 132%, about the same as that of 5,2'-dihydroxy-7-methoxyflvone (T/C=130%)

• Journal of Microbiology and Biotechnology
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• 제20권9호
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• pp.1359-1366
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• 2010

A search of the Streptomyces avermitilis genome reveals that its closest homologs are several O-methyltransferases. Among them, one gene (viz., saomt5) was cloned into the pET-15b expression vector by polymerase chain reaction using sequence-specific oligonucleotide primers. Biochemical characterization with the recombinant protein showed that SaOMT5 was S-adenosyl-L-methionine-dependent Omethyltransferase. Several compounds were tested as substrates of SaOMT5. As a result, SaOMT5 catalyzed O-methylation of flavonoids such as 6,7-dihydroxyflavone, 2',3'-dihydroxyflavone, 3',4'-dihydroxyflavone, quercetin, and 7,8-dihydroxyflavone, and phenolic compounds such as caffeic acid and caffeoyl Co-A. These reaction products were analyzed by TLC, HPLC, LC/MS, and NMR spectroscopy. In addition, SaOMT5 could convert phenolic compounds containing ortho-dihydroxy groups into O-methylated compounds, and 6,7-dihydroxyflavone was known to be the best substrate. SaOMT5 converted 6,7-dihydroxyflavone into 6-hydroxy-7-methoxyflavone and 7-hydroxy-6-methoxyflavone, and caffeic acid into ferulic acid and isoferulic acid, respectively. Moreover, SaOMT5 turned out to be a $Mg^{2+}$-dependent OMT, and the effect of $Mg^{2+}$ ion on its activity was five times greater than those of $Ca^{2+}$, $Fe^{2+}$, and $Cu^{2+}$ ions, EDTA, and metal-free medium.

• Natural Product Sciences
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• 제4권1호
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• pp.38-41
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• 1998

From the dried leaves of Isodon eriocalyx (Labiatae) six flavonoids were isolated and two of them were elucidated to be novel ones named 5,7,8,4'-tetrahydroxy-6-methoxyflavone (1), and $isothymusin-8-O-{\beta}-D-glucoside$ (2).

• Bulletin of the Korean Chemical Society
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• 제28권8호
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• pp.1261-1264
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• 2007

Bioassay-directed fractionations of the seed extracts of Trichosanthes kirilowii, have resulted in the isolation of two new compounds, 2-(4-hydroxy-3-methoxyphenyl)-3-(2-hydroxy-5-methoxyphenyl)-3-oxo-1-propanol (2) and isoetin 5'-methyl ether (5,7,2',4'-tetrahydroxy-5'-methoxyflavone) (3), together with two known compounds, 7-hydroxychromone (1) and 5,7,4'-trihydroxy-3',5'-dimethoxyflavone (tricin, 4). Their structures were characterized by spectroscopic analysis such as 2D-NMR, HRTOFMS, and UV. Compound 3 showed cytotoxicity against human lung cancer cell line A549, human skin melanoma SK-Mel-2, and mouse melanoma B16F1, with IC50 of 0.92, 8.0, and 7.23 μg/mL, respectively.