• Title/Summary/Keyword: quinone

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Synthesis of Benzoquinoxalines

  • Kwon, Nam-Koong;Lee, Hee-Soon
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.351.2-351.2
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    • 2002
  • We have previously reported the synthesis and cytotoxic activities of a series of azaanthraquinone derivatives on the model of doxorubicin(Dox). Dox is known to intercalate into DNA and to inhibit topoisomerase II activity. But in the case of Quinone compounds like Dox. its use is limited because of systemic toxicities. primarily cardiotoxicity and myelosuppression. In this study. we describe the synthesis of benzoquinoxaline derivatives as DACA analogue. DACA has a neutral chromophore and acridine moiety and posions both topoisomerases I and ll with DNA intercalating activity. In order to delineate the SAR of benzoquinoxaline derivatives. an effcient sythetic rout to the target compounds without quinone group. Various attempted removal of quinone from benzoquinoxlinedione was unsuccessful. Diels-Alder rout applied for the synthesis of the target compounds will be discussed.

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Induction of Quinone Reductase by Obtusafuran from Dalbergiae Lignum

  • Yin, Hu-Quan;Oh, Seon-Hee;Kim, Youn-Chul;Sohn, Dong-Hwan;Lee, Byung-Hoon
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.161.1-161.1
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    • 2003
  • NAD(P)H:quinone oxidoreductase (quinone reductase: QR: EC1.6.99.2), a cytosolic FAD-containing flavoprotein, form one of the important component of the phase II drug-metabolizing enzyme systems. It is found in all mammalian species tested and is expressed in many organs including the liver. QR catalyses two-electron reduction of qui nones to hydroquinones thereby suppresses the formation of superoxide anion radical. (omitted)

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EFFECT OF QUINONES ON $NADPH_2$ OXIDATION AND PHOTOSYNTHETIC $CO_2$ ASSIMILATION IN CHLORELLA PYRENOIDOSA (Chlorella Pyrenoidosa에 있어서 $NADPH_2$의 산화(酸化)와 광합성(光合性)에 의(依)한 $CO_2$ 동화작용(同化作用)에 대(對)한 Quinone의 영향(影響))

  • Cho, Duck-Hiyon
    • Applied Biological Chemistry
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    • v.11
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    • pp.29-33
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    • 1969
  • 1. The oxidizability of $NADPH_2$ by quinones in the presence of $NADPH_2$-diaphorase was tested under aerobic conditions. Also the $^{14}CO_2$-fixation rates were compared when Chlorella suspensions were pretreated with $3{\cdot}10^{-5}M$ cocentration of variou quinones for 10 minutes prior and during the $^{14}CO_2$-fixation period. 2. A close correlation seems to exist between the rate of $NADPH_2$ oxidation by quinones and the $^{14}CO_2$-fixation rate. The effect of quinones on $NADPH_2$ oxidation and $^{14}CO_2$-fixation were in the order of Dichlone>06-K>NQ>BQ. 3. It is postulated that the phytotoxicity of quinones on Chlorella is due to the deprival of $NADPH_2$ consequently inhibiting $^{14}CO_2$-fixation, thus causing death of the cells. 4. The effect of quinones on amino acids biosyn-thesis in Chlorella was one of depressed rates, which was especially noted in the case of dichlone. This would be expected from a consideration of $NADPH_2$ deprival and inhibition of $^{14}CO_2$-fixation. Sucrose synthesis was either not affected or rather stimulated, the reasons of which are not clear at the present time.

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Synthesis of Polyphenylene-1,2,4-Owadiazoles and Quinone Polymer by the Reactions of Tere- and Iso-Phthalohydroxamoyl Chlorides with Bisdipolarophiles

  • Suck-Ju Hong
    • Journal of the Korean Chemical Society
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    • v.15 no.3
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    • pp.121-125
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    • 1971
  • Tere-and Isophthalohydroxamoyl chlorides were condensed with 1, 4-benzoquinone to afford quinone type polymer with the oxidation of the ring structure. Similarly, tere-and isophthalohydroxamoyl chlorides were condensed with tere-and isophthaldioximes and terephthalonitrile to give crystalline polyphenylene-1,2,4-oxadiazoles, among which the reaction product of terephthalohydroxamoyl chloride with terephthalonitrile in xylene afforded the highest crystallinity.

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Inhibitory Effects on Cell Survival and Quinone Reductase Induced Activity of Aster yomena Fractions on Human Cancer Cells (쑥부쟁이 분획물의 in vitro 암세포증식 억제 및 QR 유도효과)

  • Jung, Bok-Mi;Lim, Sing-Sn;Park, Yun-Ja;Bae, Song-Ja
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.1
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    • pp.8-12
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    • 2005
  • This study was performed to determine the inhibitory effects on cell survival and Quinone reductase induced activity of Aster yomena (AY) on human cancer cells which, using methanol, was extracted and fractionated into five different solvent types: hexane (AYMH), ethylether (AYMEE), ethylacetate (AYMEA), butanol (AYMB) and aqueous (AYMA) partition layers. The experiment was conducted to determine cytotoxicity of various Aster yomena partition layers on HepG2, HeLa and MCF-7 cells by MTT assay. Among various partition layers of Aster yomena, A YMEE and A YMEA showed the strong cytotoxic effects on all cancer cell lines we used. The Quinone reductase (QR) induced activity on HepG2 cells, A YMH at a does of 100 $\mu$g/mL was 2.46 times more effective compared to the control value of 1.0.

Antioxidant and Quinone Reductase Inductive Activities of Various Organs of Pepper (고추 기관별 항산화 활성과 quinone reductase 유도활성)

  • Ku, Kang-Mo;Kang, Young-Hwa
    • Journal of Applied Biological Chemistry
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    • v.53 no.1
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    • pp.31-36
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    • 2010
  • We analyzed antioxidant and quinone reductase (QR) inductive activities of various organs of pepper for utilizing by-product of them. Peppers were separated into fruits, roots, stems, and leaves and extracted with methanol for the analysis. As a result, pepper leaves showed higher phenol content than other organs. Using the DPPH assay, there was not considerably different activity depending on pepper organs, but pepper leaves showed significantly higher antioxidant activity using the ABTS assay. In FTC and TBA assay, stems and leaves showed significantly higher lipidperoxidation inhibitory activity. In QR inductive assay, pepper tissues showed different QR inductive activity: leaves>roots>>stems>fruits. In addition, pepper leaves showed highest antiproliferation activity on hepa1c1c7 among pepper tissues in $50-200\;{\mu}g/mL$. These results indicate that pepper leaves have high potential to be a good functional food material due to high QR inductive and antioxidant activities.

Effect of Lipoxygenase on Oxidative Stability of ${\beta}-Carotene$ and ${\alpha}-Tocopherol$ (베타-카로틴과 알파-토코페롤의 산화안정성에 대한 리폭시게나아제의 영향)

  • Kim, Hae-Gyoung;Cheigh, Hong-Sik
    • Korean Journal of Food Science and Technology
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    • v.24 no.1
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    • pp.37-41
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    • 1992
  • Starch solid system was used to investigate the effects of lipoxygenase, linoleic acid and water activity on the oxidation of ${\beta}-carotene$ or ${\alpha}-tocopherol$. ${\beta}-carotene$ or ${\alpha}-tocopherol$ was co-oxidized severely with linoleic acid by lipoxygenase, and these were reduced to 19% and 5% of initial concentration, respectively, after 2 days storage at $a_w$ 0.72 in the system. The concentration of ${\beta}-carotene$ and the destruction rates were linearly correlated. However, the ${\beta}-carotene$ was very stable in the system without linoleic acid and lipoxygenase. The oxidation products of ${\alpha}-tocopherol$ were considered as ${\alpha}-tocopheryl$ quinone and ${\alpha}-tocopheryl$ dimer, and the level of ${\alpha}-tocopherol$ quinone increased as the reaction time increased.

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Induction of Quinone Reductase, an Anticarcinogenic Marker Enzyme, by Extract from Chrysanthemum zawadskii var. latilobum K.

  • Kim, Ju-Ryoung;Kim, Jung-Hyun;Lim, Hyun-Ae;Jang, Chan-Ho;Kim, Jang-Hoon;Kwon, Chong-Suk;Kim, Young-kyun;Kim, Jong-Sang
    • Preventive Nutrition and Food Science
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    • v.10 no.4
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    • pp.340-343
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    • 2005
  • Induction of NAD(P)H:(quinone-acceptor) oxidoreductase (QR) which promotes obligatory two electron reduction of quinones and prevents their participation in oxidative cycling and thereby the depletion of intracellular glutathione, has been used as a marker for chemopreventive agents. Induction of phase II enzyme is considered to be an important mechanism of cancer prevention. In our previous study, we assessed the quinone reductase QR-inducing activities of 216 kinds of medicinal herb extracts in cultured murine hepatoma cells, BPRc1 and hepalc1c7 cells. Among the 216 herbal extracts tested in that study, extracts from Chrysanthemum zawadskii showed significant induction of QR. In this study, we examined QR-inducing activity of solvent fractions of the herbal extract. The dichloromethane fraction of the herb showed the highest QR induction among the samples fractionated with four kinds of solvents with different polarity. The fraction also significantly induced the activity of glutathione S-transferase (GST), one of the major detoxifying enzymes, at $4{\mu}g/mL\;and\;2{\mu}g/mL$ in hepalc1c7 and BPRc1 cells, respectively. In conclusion, dichloromethane-soluble fraction of Chrysanthemum zawadskii which showed relatively strong induction of detoxifying enzymes merits further study to identify active components and evaluate their potential as cancer preventive agents.