• Title/Summary/Keyword: ${\beta}$-ME

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Phenolic Compounds from Japanese anise (Illicium anisatum L.) Twigs

  • Min, Hee-Jeong;Bae, Young-Soo
    • Journal of the Korean Wood Science and Technology
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    • 제45권4호
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    • pp.456-462
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    • 2017
  • Japanese anise (Illicium anisatum L.) twigs were collected and ground after drying, then immersed with 50% aqueous acetone for 3 days. After filtration, the extracts were fractionated with n-hexane, chloroform ($CHCl_3$), ethylacetate (EtOAc) and $H_2O$, and then freeze-dried after condensation. A portion of EtOAc soluble fraction (5.7 g) was chromatographed on a Sephadex LH-20 column with various aqueous $MeOH-H_2O$. Compound 2 and compound 3 were isolated from fraction 8 and 5, respectively. Compound 1 and compound 4 were isolated after rechromatography of fraction 7. The isolated compounds were elucidated as (+)-catechin (1), taxifolin (2), taxifolin-3-O-${\beta}$-D-(+)-xylopyranose (3) and quercitrin (4) by spectral and literature data, and by comparison with the authentic samples. Of the isolated compounds, taxifolin (2), taxifolin-3-O-${\beta}$-D-(+)-D-xylopyranose (3) and quercitrin (4) were isolated, for the first time, from the extracts of japanese anise twigs.

Nucleophilic Substitution Reactions of Aryl Thiophene-2-carbodithioates with Pyridines in Acetonitrile

  • Oh, Hyuck-Keun;Lee, Jae-Myon
    • Bulletin of the Korean Chemical Society
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    • 제25권2호
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    • pp.203-206
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    • 2004
  • The kinetics of reactions between Z-aryl thiophene-2-carbodithioates and X-pyridines in acetonitrile at 60.0 $^{\circ}C$ have been investigated. The Bronsted plots obtained for the pyridinolysis of aryl thiophene-2-carbodithioates are curved, with the center of curvature at $pK_a$ ~ 5.2 ($pK_a^{\circ}$). The Bronsted plots for these nucleophilic reactions show a change in slope from a large ( ${\beta}_X{\cong}$0.78-0.87) to a small ( ${\beta}_X{\cong}$0.33-0.35) value, which can be attributed to a change in the rate-determining step from breakdown to formation of a zwitterionic tetrahedral intermediate in the reaction path as the basicity of the pyridine nucleophile increases. A clear-cut change in the crossinteraction constants, ${\rho}_{XZ}$, from +0.92 to -0.23 supports the proposed mechanistic change. The breakpoint at $pK_a$ = 5.2 for R = thiophene ring in the present work is in agreement with those for the pyridinolysis of R = Me and 2-furyl, and attests to the insignificant effects of acyl group, R, on the breakpoint.

Kinetics and Mechanism of the Pyridinolysis of Methyl Phenyl Phosphinic Chloride in Acetonitrile

  • Adhikary, Keshab Kumar;Lee, Hai-Whang
    • Bulletin of the Korean Chemical Society
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    • 제32권6호
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    • pp.1945-1950
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    • 2011
  • The pyridinolysis of methyl phenyl phosphinic chloride is investigated kinetically in acetonitrile at -20.0 $^{\circ}C$. The Hammett and Br${\o}$nsted plots for substituent X variations in the nucleophiles are biphasic concave downwards with a break point at X = H, and unusual positive ${\rho}_X$ (= 2.94) and negative ${\beta}_X$ (= -0.48) values are obtained for the strongly basic nucleophiles. A stepwise mechanism with a rate-limiting step change from bond breaking for the weakly basic pyridines to bond formation for the strongly basic pyridines is proposed on the basis of biphasic concave downward Hammett and Br${\o}$nsted plots. Unusual positive ${\rho}_X$ and negative ${\beta}_X$ values are rationalized by the isokinetic relationship. The pyridinolyses and anilinolyses of four $R_1R_2$P(=O)Cl-type substrates, dimethyl, diethyl, methyl phenyl, and diphenyl phosphinic chlorides in acetonitrile are compared to obtain systematic information on phosphoryl transfer reaction mechanism. The combination of the two ligands, Me and Ph, shows unexpected kinetic results for both the anilinolysis and pyridinolysis: greatest magnitude of $k_H/k_D$ (= 2.10) involving deuterated anilines $[XC_6H_4NH_2(D_2)]$ for the anilinolysis, and exceptionally fast rate and biphasic concave downward free energy correlation for the pyridinolysis.

Phytochemical Constituents of the Aerial Parts from Aster hispidus

  • Lee, Sung-Ok;Choi, Sang-Zin;Choi, Sang-Un;Ryu, Shi-Yong;Lee, Kang-Ro
    • Natural Product Sciences
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    • 제10권6호
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    • pp.335-340
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    • 2004
  • The chromatographic separation of the MeOH extract of the aerial parts from Aster hispidus (Compositae) led to the isolation of eight compounds. Their structures were established by spectroscopic methods to be ${\beta}-amyrin$ (1), oleanolic acid (2), (2R)-1, 2-O-(9Z, 12Z, $15Z-dioctadecatrienoyl)-3-O-{\beta}-D-galactopyranosyl\;glycerol$ (3), trans-phytol (4), 9, 12, 15-octadecatrienoic acid (5), kaempferol (6), 3,5-dicaffeoyl quinic acid (7), 3,4-dicaffeoyl quinic acid (8) and kaempferol-3-O-rutinoside (9). Compounds 1, $3{\sim}6$ and 9 showed non-specific moderate cytotoxicity against five human tumor cell lines $(5.44{\sim}23.51\;{\mu}g/ml)$. The other compounds were of marginal activity against tested five human cancer cell lines $(9.05{\sim}>30.0\;{\mu}g/ml)$.

혹쐐기풀의 Flavonoid 성분 및 항산화 효과 (Flavonoid Constituents and Their Antioxidant Activity of Laportea bulbifera Weddell)

  • 양민철;최상진;이성옥;정애경;남정환;이규하;이강노
    • 생약학회지
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    • 제34권1호통권132호
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    • pp.18-24
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    • 2003
  • The repeated column chromatographic separation of the MeOH extract of Laportea bulbifera Weddell resulted in the isolation of five flavonoids. Structures of the isolated compounds have been identified as $isorhamnetin-7-O-{\alpha}-L-rhamnoside$ (1), $isorhamnetin-3-O-{\alpha}-L-rhamnoside$ (2), $isorhamnetin-3,7-O-{\alpha}-L-dirhamnoside$ (3), $isorhamnetin-3-O-{\alpha}-L-rhamnopyranosyl-(1{\rightarrow}2)-{\beta}-galactopyranoside$ (4), $isorhamnetin-3-O-{\alpha}-rhamosyl-(1{\rightarrow}2)-rhamnoside$ (5) by spectroscopic means.

갓 지상부에서 플라보노이드와 고급 알콜 화합물의 분리 (Isolations of Flavonoids and a Higher Alcohol from the Aerial Parts of Brassica juncea)

  • 안병관;허종문;박종철
    • 생약학회지
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    • 제38권3호통권150호
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    • pp.254-257
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    • 2007
  • The aerial parts of Brassica juncea (Cruciferae) called by brown or oriental mustard have been widely used as a spice in food and also traditional folk medicine as stimulant, diuretic and expectorant agent. And Gatkimchi made of the aerial parts of this plant are very popular in Korea. The aerial parts of this plant was refluxed with MeOH and then fractionationed with $CH_2Cl_2$, EtOAc, n-BuOH and $H_2O$, successively. One higher alcohol compound and three flavonoids were isolated from the EtOAc fraction through silica gel and Sephadex LH-20 column chromatographies. Their structures were elucidated as n-hexacosanol(1), kaempferol(2), isorhamnetin $3-O-{\beta}-D-glucopyranoside(3)$ and isorhamnetin $3-O-(6'-O-acetyl)-{\beta}-D-glucopyranoside(4)$ by comparison of spectral data with those in references. And compounds 1 and 4 were firstly isolated from this plant.

의이인(薏苡仁)의 염증성 사이토카인 발현 및 조절에 관한 연구 (Inhibitory Effect of Coicis Semen Extract(CSE) on Pro-inflammatory Mediatory)

  • 윤혜진;이유진;강미선;백정한
    • 대한한방소아과학회지
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    • 제23권1호
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    • pp.159-171
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    • 2009
  • Objectives This study was evaluated the effects of CSE the regulatory mechanism of NO and cytokines in the LPS-stimulated Raw 264.7 cells. Methods The Coicis Semen MeOH extract dissolved in EMEM for 1 hour prior to the addition of LPS(1${mu}g/ml$). The cell viability was measured by MTT assay, and Nitric Oxide production was monitored by measuring the nitrite content in culture medium. The levels of cytokine and PGE2 were analyzed by sandwich immunoassays. Results CSE inhibited the production of NO (0.03 and 0.1 mg/ml), $TNF-{\alpha}$ (0.03 and 0.1 mg/ml), $IL-1{\beta}$ (0.03 and 0.1 mg/ml), IL-6 (0.03, 0.1 mg/ml) and PGE2(0.03 and 0.1 mg/ml) in Raw 264.7 cells activated with LPS(lipopolysaccharide). Conclusion According to the results above, Coicis Semen can produce anti-inflammatory effect, which may play a role in adjunctive therapy in Gram-negative bacterial infections.

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좀 갈매나무 줄기의 플라보노이드 (Flavonoids from the Stem of Rhamnus taquetii)

  • 황완균;정혜진;고성권;이무택;김일혁
    • 약학회지
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    • 제40권4호
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    • pp.394-399
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    • 1996
  • As a series of the studies on the specific and indigenous plants of Mt. Halla, the constituents from stem of Rhamnus taquetii (Rhamnaceae) were investigated. From the water fraction of the MeOH extract, a new flavonol glycoside, kaempferide-3-O-${\alpha}$-L-rhamnopyranosyl(1->3)-${\alpha}$-L-rhamnopyranosyl(1-6)-${\beta}$-D-galactopyranoside, was isolated with three known compounds, quercetin, quercetin-3-methylether, kaempferol, by column chromatographic separation using Amberlite XAD-2, ODS-gel and Sephadex LH-20 and elucidated physico-chemical evidences($^1H-NMR,\;^{13}C-NMR$,IR, EI-Mass, FAB-Mass, and G.C.),respectively.

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포공영(蒲公英)의 염증성 사이토카인 발현 및 조절에 관한 연구 (Inhibitory Effect of Taraxaci Herba Extract (THE) on Pro-inflammatory Mediatory)

  • 노경호;백정한
    • 대한한방소아과학회지
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    • 제23권3호
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    • pp.165-176
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    • 2009
  • Objectives The purpose of this study is to find out the effect of Taraxaci Herba Extract (THE), LPS, on pro-inflammatory mediatory. Methods After the treatment of Taraxaci Herba MeOH extract dissolved in EMEM for 1 hour prior to the addition of LPS ($1\;{\mu}g/ml$), cell viability was measured by MTT assay, Nitric Oxide production was monitored by measuring the nitrite content in culture medium. And levels of cytokine and PGE2 were analyzed by sandwich immunoassays. Results THE inhibited the production of nitrite and nitrate (0.03 and 0.1 mg/ml), TNF-$\alpha$, (0.03 and 0.1 mg/ml), IL-$1{\beta}$(0.03 and 0.1 mg/ml), IL-6 (0.01, 0.03 and 0.1 mg/ml) and PGE2(0.03 and 0.1 mg/ml) activated with LPS. In Raw 264.7 cells activated with lipopolysaccharide. Conclusions According to the results above, Taraxaci Herba can produce anti-inflammatory effect, which may play a role in adjunctive therapy in Gram-negative bacterial infections.

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Hydrolysable Tannins from Cercidiphyllum japonicum Bark

  • Lee, Min-Sung;Min, Hee-Jeong;Si, Chuan-Ling;Bae, Young-Soo
    • Journal of the Korean Wood Science and Technology
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    • 제44권4호
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    • pp.559-570
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    • 2016
  • The EtOAc and $H_2O$ soluble fractions of Katsura tree (Cercidiphyllum japonicum Sieb. Et Zucc) bark extracts were chromatographed on a Sephadex LH-20 column with various aqueous MeOH. Gallic acid (1), methyl galate (2), kurigalin (3), 1,2,3,6-tetra-O-galloyl-${\beta}$-D-glucose (4) and 1,2,3,4,6-penta-O-galloyl-${\beta}$-D-glucose (5) were isolated from EtOAc fraction. Isocorilagin (6) and methyl galate (2) were separated from $H_2O$ fraction. The structure determination was done by $^1H$ and $^{13}C$ NMR. Of these isolated compounds, methyl galate (2), kurigalin (3) and isocorilagin (6) were isolated, for the first time, from the bark extracts of Cercidiphyllum japonicum.