• Title/Summary/Keyword: Natural ester

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Triterpenoids and Flavonoids Isolated from the Leaves of Alnus firma (사방오리 잎의 Triterpenoid 및 Flavonoid 화합물)

  • Yu, Young-Beob;Nakamura, Norio;Miyashiro, Hirotsugu;Hattori, Masao;Park, Jong-Cheol
    • Korean Journal of Pharmacognosy
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    • v.38 no.1
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    • pp.76-83
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    • 2007
  • In this study, three triterpenoids, two steroids and nine flavonoids were isolated from the leaves of Alnus firma Sieb. et Zucc. On the basis of spectroscopic evidences, the structures of these compounds were established as ${\beta}$-amyrin acetate, ${\beta}$-amyrin, ${\beta}$-sitosterol, alnustic acid methyl ester, ${\beta}$-sitosterol glucoside, pinocembrin, alnustinol, quercetin, quercetin-3-O-${\alpha}$-L-arabinofuranoside, quercetin-3-O-${\alpha}$-L -rhamnopyranoside, quercetin-3-O-${\beta}$-D-glucopyranoside, myricetin-3-O-${\beta}$-D-galac-topyranoside, (+)-catechin and (-)-epicatechin.

Lupane-Triterpenes from the Leaves of Brassaiopsis glomerulata

  • Kiem, Phan-Van;Dat, Nguyen-Tien;Minh, Chau-Van;Lee, Jung-Joon;Kim, Young-Ho
    • Archives of Pharmacal Research
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    • v.26 no.8
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    • pp.594-596
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    • 2003
  • Three known lupane-triterpenes, 3a-hydroxy-lup-20(29)-en-23,28-dioic acid (1), 3$\alpha$-hydroxylup-20(29)-en-23,28-dioic acid 28-Ο-$\alpha$-L-rhamnopyranosyl-(1$\rightarrow4)-\beta-D-glucopyranosyl-(1\rightarow6)-\beta$-D-glucopyranosyl ester (acankoreoside A, 2) and $3\alpha$, $11\alpha$-dihydroxy-23-oxo-lup-20(29)-en-28-oic acid (3) were isolated from the leaves of Brassaiopsis glomerulata (Blume) Regel, a species of Araliaceae family growing in Vietnam. Their structures were determined on the basis of spectroscopic data.

Protoberberine Alkaloids and their Reversal Activity of P-gp Expressed Multidrug Resistance (MDR) from the Rhizome of Coptis japonica Makino

  • Min, Yong-Deuk;Yang, Min-Cheol;Lee, Kyu-Ha;Kim, Kyung-Ran;Choi, Sang-Un;Lee, Kang-Ro
    • Archives of Pharmacal Research
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    • v.29 no.9
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    • pp.757-761
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    • 2006
  • Six protoberberine alkaloids were isolated from the chloroform layer of the rhizome of Coptis japonica Makino (Ranunculaceae). The structures of the isolated compounds were determined to be 6-([1,3]dioxolo[4,5-g]isoquinoline-5-carbonyl)-2,3-dimethoxy-benzoic acid methyl ester (1), oxyberberine (2), 8-oxo-epiberberine (3), 8-oxocoptisine (4), berberine (5) and palmatine (6) by physicochemical and spectroscopic methods. The compound 3 (8-oxo-epiberberine) was first isolated from natural sources. The compounds were tested for cytotoxicity against five tumor cell lines in vitro by SRB method, and also tested for the MDR reversal activities. Compound 4 was of significant P-gp MDR inhibition activity with ED50 value $0.018\;{\mu}g/mL$ in MES-SA/DX5 cell and $0.0005\;{\mu}g/mL$ in HCT15 cell, respectively.

Synthesis and Physical Properties of Novel Fluorinated Liquid Crystalline Compounds

  • Keum, Hye-Won;Roh, Su-Dong;Do, Yun-Sun;Lee, Jae-Ho;Kim, Yong-Bae
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.1142-1146
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    • 2004
  • The synthetic route and physical properties for three-ring derivatives, trans-2,3,2',3'-tetrafluoro-4-alkyl-4'-(4-alkyl-cyclohexyl)-biphenyl and 4-alkyl-cyclohexane carboxylic acid 2,3,2',3',4'-pentafluoro-biphenyl-4-yl ester are presented. They exhibit broad range nematic phases exceeding 30K and low viscosity of nematic liquid crystal mixtures containing these materials. Their viscosity is compared with that of homologues with a lateral isothiocyanate group and show large negative dielectric anisotropies. The threshold voltage $V_{th}$ was low enough to be operated at a driving voltage of 5V. Our novel LC compounds are suitable materials for the improvement of dielectric anisotropy of vertical align liquid crystal displays (VA-LDCs).

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Phytochemical Constituents of Amomum xanthioides

  • Choi, Jung-Wook;Kim, Ki-Hyun;Lee, Il-Kyun;Choi, Sang-Un;Lee, Kang-Ro
    • Natural Product Sciences
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    • v.15 no.1
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    • pp.44-49
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    • 2009
  • Seven monoterpenes, three sesquiterpenes, three phenolics and one flavonoid were isolated from the MeOH extract of Amomum xanthioides. Their structures were determined by spectroscopic methods to be caryophyllene oxide (1), bornyl acetate (2), nerolidol (3), spathulenol (4), (-)-borneol (5), (+)-5-endohydroxycamphor (6), vanillic acid (7), protocatechuic acid methyl ester (8), betulabuside A (9), (1R,4S,6R)-6-hydroxyfenchan-2-one-6-O-$\beta$-D-glucopyranoside (10), (1S,4R,6S)-6-hydroxybornan-2-one-6-O-$\beta$-D-glucopyranoside (11), (1R,2S,4S,5R)-angelicoidenol 2-O-$\beta$-D-glucopyranoside (12), 1-O-vanilloyl-$\beta$-D-glucopyranoside (13), and quercetin-3-rhamnopyranoside (14). Compounds 6-14 were isolated for the first time from this plant source. Compounds 3 and 4 exhibited moderate cytotoxicity against four human cancer cell lines in vitro using a SRB bioassay.

Diffraction Behaviors of New Photopolymers and their Diffuser Properties

  • Yoon, Hyuk;Kim, Jae-Hong;Lee, Seung-Hwan;Paek, Sang-Hyon;Choi, Dong-Hoon
    • Journal of Information Display
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    • v.5 no.1
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    • pp.22-27
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    • 2004
  • Photopolymers are quite promising candidates for holographic data storage and diffusers because of their high sensitivity and high refractive index modulation. New photopolymers were prepared using the cellulose ester binder bearing different kinds of monomer. The holographic gratings were elaborated successfully in these photopolymer samples by conventional optical interference method. We investigated the dynamic behavior of the diffraction efficiency and the effect of the functionality of the monomer doped into the polymer binder. Triacrylate monomer doped photopolymer showed the highest diffraction efficiency of around 80-90 %, even under low intensity of writing beam (I=2 mW/$cm^2$). We inscribed the gratings of the glass diffuser on the surface of the photopolymer and investigated their diffusion properties.

Synthesis of 7,8-Dichloro-6-Nitro-1H-1,5-Benzodiazephine-2,4-(3H, 5H)-dione as a potential NMDA Receptor Glycine Site Antagonist

  • Hwang, Ki-Jun
    • Archives of Pharmacal Research
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    • v.23 no.1
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    • pp.31-34
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    • 2000
  • An efficient procedure for the preparation of 7,8-dichloro-6-nitro-1H-1,5-benzodiazepine-2,4-(3H, 5H)-dione(7) as a potential lead compound for the NMDA receptor glycine binding site antagonist, starting from readily available 4,5-dichloro-2-nitroaniline(8), is described. The key step in the synthesis involves the cyclization of malonic ester amide 10 to compound 11.

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Phytochemical Study of the Aerial Parts of Conyza discoridis Growing in Saudi Arabia

  • Alqasoumi, Saleh I.
    • Natural Product Sciences
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    • v.15 no.2
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    • pp.66-70
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    • 2009
  • Phytochemical investigation of the aerial parts of Conyza discoridis (L.) Desf. resulted in the isolation of the new sesquiterpene dilactone ester vernomenin-6-(2-hydroxymethyl)-acrylate (4) and two known sesquiterpene dilactones vernolepin (1) and vernomenin (3). Two known flavonols, 3-O-methylquercetin (2) and transilin (3-O-methylquercetin 7-O-${\beta}$-D-glucopyranoside) (5), were also identified. The structures were determined utilizing physical, chemical and spectral methods.

Inhibitory Activity of IL-6 Production by Flavonoids and Phenolic Compounds from Geranium thunbergii

  • Liu, Qing-He;Woo, Eun-Rhan
    • Natural Product Sciences
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    • v.14 no.1
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    • pp.16-20
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    • 2008
  • Three flavonoids (1 - 3) and three phenolic compounds (4 - 6) were isolated from the whole plant of Geranium thunbergii Sieb. et Zucc (Geraniaceae). Their structures were determined by chemical and spectral analysis. These compounds were examined for the inhibitory activity of IL-6 production in $TNF-{\alpha}$ stimulated MG-63 cell. Among the isolated compounds, gallic acid (4) and gallic acid methyl ester (6) showed potent inhibitory activity.

A Comparative Study on the Manufacturing Processes of Red Wine (포도주(葡萄酒) 제조방법(製造方法)에 관(關)한 비교연구(比較硏究))

  • Byun, Sang-Sook
    • Journal of Nutrition and Health
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    • v.13 no.3
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    • pp.139-144
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    • 1980
  • A study was conducted to examine the physical and chemical changes of wines fermented from three different varieties by three different methods. The products were evaluated by twenty subjects on color, aroma, and taste. The results were as follows; 1) The moisture contents of those varieties were ranged from 90. 70 to 90.82% The Brix sugar and sugar contents were in order of Muscat Bailey A>Alden>Cambell Early. The titratable acidity was higher in Muscat Bailey A and Alden than in Cambell Early while PH of Cambell Early was higher than those of the two others. 2) The specific gravities of the products were slightly decreased as the fermentation progressed. 3) The yeast-fermentation showed the higher degree of alcoholic contents compared to the natural fermentations. of the natural fermentations, the washed-natural fermentation resulted in the lower alcoholic contents than unwashed one. 4) The PH's were also higher in the yeast-fermentation products than in the natural fermentation groups. The difference, however, was smaller as the fermentation progressed further. 5) The total ester coutents of the yeast fermentation group were slightly higher at the beginning of the fermentation than those of the natural fermentation products and the contents were increased during the fermentation in overall. 6) Twenty panel mentors judged the ripe wine products and the order of preference was Alden>Muscat Baliey A>Cabell Early. They preferred the yeast-fermentation wine to the natural fermentation products.

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