• Bulletin of the Korean Chemical Society
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• 제28권7호
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• pp.1159-1166
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• 2007

New unsymmetrical trans-stilbenes have been prepared by the sequential coupling reactions of bromobenzenesulfonate with formylarylboronic acids, benzylphosphonates and arylmagnesium bromides and characterized. The nickel-catalyzed reactions of stilbenesulfonates with aryl Grignard reagents produced the corresponding stilbenes via the nucleophilic aromatic substitution of the neopentyloxysulfonyl group by aryl nucleophiles. The great chemoselectivity of the alkyloxysulfonyl group allows the stepwise construction of unsymmetrical trans-stilbenes possessing terphenyl moieties. This procedure appears to be a promising and conceptually straightforward route for the parallel synthesis of various unsymmetrical stilbenes as well as other highly conjugated hydrocarbons.

• Natural Product Sciences
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• 제13권4호
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• pp.369-372
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• 2007

Oxidative stress induced by reactive oxygen species (ROS) has been suggested to be the cause of various degenerative diseases as well as aging. To evaluate the antioxidant potential of stilbenes, we have investigated the cytoprotective effect of 10 stilbenes derived from plants on the oxidative stress induced by tertiary butyl hydroperoxide (t-BuOOH). Of the stilbenes tested, piceatannol (3) showed the most potent activity, which was further investigated using an animal model. When 3 (30 or 10 mg/kg) was topically administered prior to UVB irradiation, the amount of the thiobarbituric acid reactive substances (TBARS) was significantly reduced compared to that of the control (vehicle). Our findings suggest that piceatannol is capable of protecting cells and tissues from oxidative stress.

• 대한화학회지
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• 제36권1호
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• pp.38-43
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• 1992

치환 스틸벤 계열에 대해 HMO법으로 Hammett치환기 상수를 해석하였다. 이 계열에서 치환기 상수에 대한 유도효과와 공명효과의 기여를 양자화학적 지수로 취하여 계산한 이론값이 Hammett 치환기 상수 ${\sigma}_p$와 병행성이 있음을 알았으며 이 이론값으로 치환 스틸벤의 쌍극자능륙에 미치는 치환기 효과를 설명할 수 있었다. 아울러 이 화합물의 전자전이에 대한 최대 흡수파장$({\lambda}_{max})$은 HOMO와 LUMO 에너지의 창에 의존됨이 확인되었다.

• Natural Product Sciences
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• 제3권1호
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• pp.49-54
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• 1997

We studied the attachment-repelling activity of flavonoids, stilbenes, and their glycosides against the blue mussel Mytilus edulis galloprouincialis. Molecular mechanics calculations have shown that the most stable conformations of potent repellents 29 and 32 were the same. On the basis of these results, structure-activity relationships of these compounds are discussed.

• Plant Biotechnology Reports
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• 제3권2호
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• pp.135-138
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• 2009

Cell cultures of Cayratia trifolia (Vitaceae), a tropical lianas, were maintained in Murashige and Skoog's medium containing $0.25mg\;1^{-1}$ NAA, $0.2mg\;1^{-1}$ kinetin and casein hydrolysate $250mg\;1^{-1}$. Cell suspension cultures of C. trifolia accumulate stilbenes (piceid, resveratrol, viniferin, ampelopsin), which on elicitation by any of $500{\mu}M$ salicylic acid, $100{\mu}M$ methyl jasmonate, $500{\mu}M$ ethrel and $500mg\;1^{-1}$ yeast extract, added on the 7th day, were enhanced by 3- to 6-fold ($5-11mg\;1^{-1}$) by the 15th day.

• 한국약용작물학회지
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• 제13권2호
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• pp.80-84
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• 2005

Five known anthraquinones, physcion (1), I-O-methylemodin (2), emodin (3), $physcion-8-O-{\beta},-D-glucopyranoside$ (5), $emodin-8-O-{\beta},-D-glucopyranoside$ (6) and two known stilbenes, trans-resveratrol (4), $trans-resveratrol-3-O-{\beta},-D-glucopyranoside$ (7) were isolated from MeOH extract of Reynoutria sachalinensis (Polygonaceae). All structures were unambiguously established by 1D and 2D NMR and MS data and the compounds were evaluated for their cytotoxicity against L1210, HL-60, BI6F10 tumor cell lines in MTT assay. Among the compounds, trans-resveratrol (4) exhibited significant cytotoxic activity with $IC_{50}$ values of 9.2, 6.7 and $9.8\;{\mu}g/ml$, against the test cell lines respectively, but compounds 1-3 exhibited the moderate cytotoxic activity.

• Archives of Pharmacal Research
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• 제25권3호
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• pp.293-299
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• 2002

Cytotoxic and antimutagenic effects of a novel cis-$\varepsilon$-viniferin and five known stilbenes, transresveratrol, trans-$\varepsilon$-viniferin, gnetin H, suffruticosols A and B, isolated from the seeds of Paeonia lactiflora Pall. (Paeoniaceae) were determined against five different cancer cell lines, and mutagenicity of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in Salmonella typhimurium TA100, respectively. Six stilbenes showed cytotoxic activity in a dose-dependent manner, and especially did potent cytotoxic activity against C6 (mouse glioma) cancer cell with $IC_{50}$ values ranging from 8.2 to $20.5{\;}{\mu\textrm{g}}/ml$. trans-Resveratrol showed significant cytotoxic activity against HepG2 (liver hepatoma) and HT-29 (colon) human cancer cell lines with $IC_{50}$ values of 11.8 and 25.2 g/ml, respectively. In contrast, trans-$\varepsilon$-viniferin and cis--viniferin, and gnetin H exhibited marked cytotoxic activity against Hela (cervicse) and MCF-7 (breast) human cancer cell lines with $IC_{50}$ values of 20.4, 21.5, and $12.9{\;}{\mu\textrm{g}}/ml$, respectively. However, suffruticosol A and B had less cytotoxic effect against all cancer cells except C6. Meanwhile, six stilbenes exerted antimutagenic activity in a dose-dependent fashion. Of them, trans-resveratrol exhibited the strongest antimutagenic effect against MNNG with $IC_{50}$ value of $27.0{\;}{\mu\textrm{g}}/plate$, while other five resveratrol oligomers also did moderate antimutagenic activity with $IC_{50}$ values ranging from 31.7 to $35.2{\;}{\mu\textrm{g}}/plate$.

• Archives of Pharmacal Research
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• 제21권6호
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• pp.703-706
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• 1998

The anticomplementary activity of stilbenes from medicinal plants in Korea was investigated in vitro. 3,5-Dihydroxy-4'-methoxystilbene (3) was most potent with $IC_{50}$ value of $1.5{\times}10^{-4}M$ followed by rhapontigenin (4), oxyresverastrol (2), 2,3,4',5-tetrahydroxystilbene-2-O-beta-glucoside (9), rhaponticin (8), resverastrol (1), and piceid (7). The activity was found to be increased by a methylation on a hydroxy group of C-4' of 1, but decreased by further methylation on hydroxy groups of C-3 and C-5 and glucosylation on any hydroxy group of 1. Addition of hydroxy group on C-2' of 1 or C-3' of 3 was little affected on the anticomplementary activity but the activity was increased by O-glucosylation on C-2 of 1.

• Natural Product Sciences
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• 제14권2호
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• pp.143-146
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• 2008

Protein tyrosine phosphatase 1B (PTP1B) is emerging as a potential therapeutic target for the treatment of type-2 diabetes and obesity. To search for new types of PTP1B inhibitors, we have undertaken in vitro enzyme assay for some anthraquinones and stilbenes isolated from plants. Of the anthraquinones tested, physcion (1), 1-O-methylemodin (2), and emodin (3) showed high activities, with $IC_{50}$ values of 7.6, 7.0, and $3.8{\mu}g/mL$, respectively, while the anthraquinone glycosides, physcion-8-O-${\beta}$-D-glucopyranoside (4) and emodin-8- O-${\beta}$-D-glucopyranoside (5), were less active than their aglycones. All the stilbenens (6 - 15) slightly inhibited PTP1B activity at high concentration of $30{\mu}g/mL$. Our findings suggest that the hypoglycemic effect of anthraquinones may be associated with their PTP1B inhibitory activity.

• 원예과학기술지
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• 제29권4호
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• pp.374-381
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• 2011

Stilbene 화합물은 항산화 및 항균 활성을 가지는 폴리페놀계의 천연물이다. 포도를 포함하는 몇몇 종류의 식물에서 stilbene 화합물은 resveratrol의 유도체로서 매우 다양한 형태로 존재한다. 자외선 조사 포도 잎에서 stibene 화합물을 정량 분석하기에 앞서, 먼저 각 stilbene 화합물을 동정하기 위한 실험을 수행하였다. 이를 위하여, 자외선을 심하게 조사한 잎에서 stilbene 배당체를 추출하였다. 추출한 배당체 시료는 ${\beta}$-glucosidase를 이용하여 가수분해한 후, 특정 stilbene 화합물의 질량에 해당하는 m/z에서 HPLC-mass spectrometer를 이용하여 분석하였다. 효소적 가수분해에 의해 chromatogram상에는 glycoside에 해당할 것으로 예상되는 peak의 감소와 aglycone에 해당할 것으로 예상되는 peak 증가가 나타났다. 또한 stilbene 화합물의 광 이성질화를 유도하기 위하여 시료를 일광에 노출하였으며, 광 노출에 의해 trans-isomer에 해당할 것으로 예상되는 peak의 소멸과 cis-isomer에 해당할 것으로 예상되는 peak의 생성이 나타났다. Chromatogram상의 peak의 이러한 증감으로부터 각 peak의 성분을 유추하였다. 이러한 방법으로 포도 잎에서 16종의 stilbene 화합물을 동정할 수 있었으며 자외선을 조사한 포도 잎에서 동정된 화합물에 대한 정량적 분석을 수행하였다. 자외선 조사는 포도 잎에서 총 stilbene 함량의 상당한 증가를 가져왔는데 특히 trans-resveratrol은 수백 배 증가하였다. 또한, resveratrol보다 더 강한 radical 소거 활성을 가지지만 무처리 잎에서는 단지 미량으로만 존재하는 piceatannol의 함량 역시 수십배 증가하였다. 자외선 조사에 의한 이러한 stilbene 함량의 증가는 hormesis 현상으로서 포도의 스트레스 대응 반응의 하나로 생각된다.