• Title/Summary/Keyword: ${\beta}$-ME

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Elimination Reactions of Aryl Furylacetates Promoted by R2NH-R2NH2 + in 70 mol% MeCN(aq). Effects of β-Aryl on the Ketene-Forming Transition-State

  • Pyun, Sang Yong;Kim, Ju Chang;Cho, Bong Rae
    • Bulletin of the Korean Chemical Society
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    • v.35 no.7
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    • pp.2143-2147
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    • 2014
  • Ketene-forming elimination from 2-X-4-nitrophenyl furylacetates (1a-d) promoted by $R_2NH-R_2NH_2{^+}$ in 70 mol % MeCN(aq) has been studied kinetically. When X = Cl and $NO_2$, the reactions exhibited second-order kinetics as well as Br$\ddot{o}$nsted ${\beta}$ = 0.37-0.54 and $|{\beta}_{lg}|$ = 0.31-0.45. The Br$\ddot{o}$nsted ${\beta}$ decreased with a poorer leaving group and $|{\beta}_{lg}|$ increased with a weaker base. The results are consistent with an E2 mechanism. When the leaving group was changed to a poorer one [X= H (1a) and $OCH_3$ (1b)], the reaction mechanism changed to the competing E2 and E1cb mechanisms. A further change to the E1cb mechanism was realized for the reaction of 1a with $i-Pr_2NH/i-Pr_2NH_2{^+}$ in 70 mol % MeCN-30 mol % $D_2O$. By comparing the kinetic results in this study with the existing data for $ArCH_2C(O)OC_6H_3-2-X-4-NO_2$, the effect of the ${\beta}$-aryl group on the ketene-forming elimination was assessed.

Biolosical Activities of Isolated Compounds from Peucedani Radix (식방풍의 성분분리 및 생리활성)

  • Kim, Do-Hoon;Han, Chi-Su;Kim, Gi-Eun;Kim, Jin-Hyo;Kim, Sung-Gun;Kim, Ho-Kyoung;Oh, O-Jin;Whang, Wan-Kyunn
    • YAKHAK HOEJI
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    • v.53 no.3
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    • pp.130-137
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    • 2009
  • In this study, isolation of antioxidative compounds was performed for development of anti-oxidizing agent. $CHCl_3$, $H_2O$, 30%, 60% MeOH, MeOH fractions were examined antioxidative activity by DPPH, test of inhibition on NO production. It was revealed that 30%, 60% MeOH and $CHCl_3$ fractions had significant antioxidative activity. In 30% MeOH and 60% MeOH, $CHCl_3$ fraction, six compounds were isolated and elucidated as adenosine(I), guanosine(II), peucedanol 7-O-$\beta$-D-apiofuranosyl(1$\rightarrow$6)-$\beta$-glucopyranoside(III), peucedanol 7-O-$\beta$-D-glucopyranoside(IV), peucedanol(V) and scopoletin(VI) by physicochemical data and spectroscopic methods. (Negative FAB-MS, $^{1}H-NMR$, $^{13}C-NMR$). The results from antioxidative activity screening for the each compound showed that compound IV was relatively superior antioxidant ability. In anti-inflammatory activation assay, compound III, IV, VI had concentration-dependent-activity and compound IV had superior anti-inflammatory ability. These results suggest that Peucedani Radix might be developed as a potent anti-oxidative, anti-inflammatory agents and ingredients for related functional foods.

Effects of MeOH Extract from Stem Bark of Plantocracy strobilacea on the Metabolism of Amyloid Precursor Protein in Neuroblastoma Cells (화향수(化香樹) 수피(樹皮)의 메탄올 추출물이 신경세포에서 아밀로이드 전구단백질의 대사에 미치는 영향)

  • Jiang, Gui Bao;Leem, Jae Yoon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.27 no.1
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    • pp.57-62
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    • 2013
  • Alzheimer's disease (AD), one of the most common forms of dementia, is characterized pathologically by the presence of intracellular neurofibrillary tangles and deposition of ${\beta}$-amyloid ($A{\beta}$) peptides of 40-42 residues, which are generated by processing of amyloid precursor protein (APP). $A{\beta}$ has been believed to be neurotoxic and now is also considered to have a role on the mechanism of memory dysfunction. Here, we show that MeOH extract from stem bark of Platycarya strobilacea Sieb. et. Zucc. (PSM) affects on the processing of APP from the APPswe over-expressing Neuro2a cell line. We found that PSM may regulate the processing of APP and increase the sAPP${\alpha}$. PSM does not change the protein level of presenilin and nicastrin, however, it reduces the protein expression level of BACE1. In addition, PSM reduces the secretion level of $A{\beta}42$ and $A{\beta}40$ from the cell line without toxicity. We suggest that Platycarya strobilacea may be useful as a herbal medicine to treat Alzheimer's disease.

Effects of MeOH Extract of Impatiens balsamina L. on the Metabolism of Amyloid Precursor Protein in Neuroblastoma Cells (봉선화 전초의 메탄올 추출물이 신경세포에서 아밀로이드 전구단백질의 대사에 미치는 영향)

  • Jo, Yoon Jeong;Leem, Jae Yoon
    • Korean Journal of Pharmacognosy
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    • v.46 no.1
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    • pp.72-77
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    • 2015
  • One of the most common forms of dementia, Alzheimer's disease (AD) is a progressive neurodegenerative disorder symptomatically characterized by impairment in memory and cognitive abilities. AD is characterized pathologically by the presence of intracellular neurofibrillary tangles and deposition of ${\beta}$-amyloid ($A{\beta}$) peptides, believed to be neurotoxic and now is also considered to have a role on the mechanism of memory dysfunction. In this study, we tested that MeOH extract of Impatiens balsamina L. (IBM) affects on the processing of APP from the APPswe over-expressing Neuro2a cell line. We found that IBM increased over 2 folds of the $sAPP{\alpha}$ secretion level, a main metabolite of ${\alpha}$-secretase. We shown that IBM reduced the secretion level of $A{\beta}42$ and $A{\beta}40$ without cytotoxicity. BACE (${\beta}$-site APP cleaving enzyme) FRET assay shown that BACE activity was specifically decreased in the presence of IBM. We suggest that Impatiens balsamina L. may be an useful source to develop a herbal medicine of BACE inhibitor for Alzheimer's disease.

Pharmaco-Constituents of Korean Cultivated Rhubarb Leaves -The Anthraquinones from Leaves- (한국산 재배대황엽의 약효성분 -엽의 안트라퀴논-)

  • Ham, In-Hye;Kim, Il-Hyuk
    • YAKHAK HOEJI
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    • v.38 no.4
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    • pp.410-417
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    • 1994
  • As one of the studies for Korean cultivated Rhubarb, which has been used stomachic bitter, laxative and purgative, etc, MeOH extract of the leaves was fractionated with ether, ethylacetate. From the ether fraction of MeOH extract, two anthraquinone derivatives, 1,6,8-trihydroxy-3-methyl anthraquinone(emodin, $C_{15}H_{10}O_5$), 1,6,8-trihydroxy-3-hydroxymethyl anthraquinone (citrerosein, $C_{15}H_{10}O_6$) and from the ethyl acetate fraction of MeOH extract, one anthraquinone derivative, emodin-8-${\beta}$-D-glucopyranoside$(C_{21}H_{20}O_{10})$ were isolated and identified through the physico-chemical properties and spectroscopic evidences(UV, IR, NMR, Mass), respectively.

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Anti-Rheumatoid Arthritis Effect of the Kochia scoparia Fruits and Activity Comparison of Momordin Ic, its Prosapogenin and Sapogenin

  • Choi, Jongwon;Lee, Kyung-Tae;Jung, Hyun-Ju;Park, Hee-Sun;Park, Hee-Juhn
    • Archives of Pharmacal Research
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    • v.25 no.3
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    • pp.336-342
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    • 2002
  • MeOH extract of Kochia scoparia was fractionated into $CHCl_3-$, EtOAc- and BuOH extracts and the last fraction were hydrolyzed by 3%-NaOH ($MeOH-H_2O$) to compare the bioactivities on antinociceptive and anti-inflammatory effects. Silica gel column chromatography of BuOH fraction afforded a large amount of $3-Ο-{\beta}-D-xylopyranosyl {\;}(1{\rightarrow}3)-{\beta}-D-glucuronopyranosyl$ oleanolic acid (momordin Ic, 4) and that of acid hydrolysate of BuOH fraction gave $3-Ο-{\beta}-D-glucuronopyranosyl oleanolic$ acid (momordin Ib, 3), its 6'-Ο-methyl ester (2) and oleanolic acid (1). Silica gel column chromatography of alkaline hydrolysate afforded a large amount of 4. MeOH extract and both EtOAc- and BuOH fractions were active in the rheumatoidal rat induced Freund's complete adjuvant reagent (FCA) whereas $CHCl_3$ fraction was inactive. Compound 1 and 4 showed significant activities in the same assay but oleanolic acid 3-Ο-glucuronopyranoside (3) showed no activity. These fashions were also observed in carrageenan-induced edema of the rat and in the antinociceptive activity tests undertaken in hot plate- and writhing methods. These results suggest that momordin Ic and its aglycone, oleanolic acid, could be active principles for rheumatoid arthritis.

The Anti-oxidative Compounds of Smilax riparia Leaves (Smilax riparia 잎의 항산화 성분)

  • 조은선;김정일;김호현;전인주;함인혜;황완균
    • YAKHAK HOEJI
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    • v.47 no.5
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    • pp.300-306
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    • 2003
  • Rhizoma of Smilax china has been used as anti-inflammatory and analgesic, antiedemic agent in Korean folk medicine. In order to investigate the efficacy of anti-oxidative activity, the activity-guided fractionation and the isolation were performed. Each fractions ($H_2O$ fraction, 20%, 40%, 60%, 100% MeOH fractions and CHCl$_3$ fraction) was examined antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging potential. It was revealed that 40%, 20% MeOH fractions and $H_2O$ fractions have significant anti-oxidative activity. From 40% and 20% MeOH fractions two flavonoid glycosides and one procyanidin were isolated and elucidated apigenin-7-Ο-$\alpha$-L-rhamnopyranosyl(1\longrightarrow2)-$\beta$-D-glucopyranoside, apigenin-7-Ο-$\alpha$-L-rhamnopyranosyl(1\longrightarrow6)-$\beta$-D-glucopyranoside and catechin(4$\alpha$\longrightarrow6)epicatechin through their physicochemical data and IR, FAB-MS, $^{13}$ C-NMR, and $^1$H-NMR analysis with authentics, respectively. The isolated compounds were examined by DPPH method. Apigenin-7-Ο-$\alpha$-L-rhamnopyranosyl(1\longrightarrow2)-$\beta$-D-glucopyranoside and catechin (4$\alpha$\longrightarrow6) epicatechin showed powerful radical scavenging activities on DPPH radical among three compounds.

Determination of Flavonoid by HPLC and Biological Activities from the Leaves of Cudrania tricuspidata Bureau (꾸지뽕나무 잎의 생리활성 및 HPLC에 의한 성분의 정량)

  • 김성환;김남재;최재수;박종철
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.22 no.1
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    • pp.68-72
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    • 1993
  • The methanol extract of the leaves of Cudrania tricuspidata and ethyl acetate fraction from the methanol extract showed inhibition for trypsin activity and the growth inhibition of Staphylococcus aureus. The content of kaempferol 7-O-$\beta$-D-glucopyranoside isolated from this plant was determined by HPLC and it was about 0.31% for the methanol extract.

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Culture of Clonal Lines in Porcine Fetal Fibroblast Cells (돼지 태아섬유아세포 Clonal Lines의 배양)

  • Kwon, D. J.;Park, C. K.;B. K. Yang;Kim, C. I.;H. T. Cheong
    • Reproductive and Developmental Biology
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    • v.28 no.1
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    • pp.7-12
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    • 2004
  • This study was performed to establish the effective culture condition for the establishment of clonal lines from porcine fetal fibroblast cells. Fibroblasts derived from a pig fetus (Day 50) were cultured and passaged two times before use. A single cell was seeded in 96-well plates, cultured in medium supplemented with different concentrations of FBS, catalase or $\beta$-mercaptoethanol ($\beta$ME), and classified by cell size and morphology. Cells were passaged two times into 4-well dish before freezing. The establishment efficiencies were not different among different concentrations of FBS (0.3 to 5.1%). However, population doubling time (PDT) was significantly decreased by increasing the FBS concentration (P<0.05). The establishment efficiency of $\beta$ME-added group (10.4%) was significantly higher than those of catalase-added and control groups (3.5%, and 3.5%, respectively, p<0.05), and PDT was significantly decreased (23.6 vs 28.1, and 25.5 h, respectively, p<0.05). However, catalase did not show a positive effect on the establishment efficiency. Cell size and morphology did not affect the establishment efficiency and PDT of clonal lines. The result of present study shows that the establishment efficiency of clonal cell lines can be enhanced by the culture in media supplemented with 30% FBS and $\beta$ME.

Development of Radiopharmaceutical DW-166HC for Anticancer drug

  • Man, Ryu-Jei
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1999.04a
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    • pp.53-61
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    • 1999
  • Radiation therapy has been used for the cancer treatment and radiation synovectomy$\^$1-3)/. There are two kinds of radiation therapy; the external radiation therapy and the internal radiation therapy. Hitherto, the external radiation therapy has been widely used, but for the lack of its selectivity it requires strong radiation dose and causes the irritation and damage of the normal tissue or organ. Therefore many researchers give their interests to the internal radiation therapy in which the radioactive materials are injected directly into the target organ or tissue. Many ${\beta}$-emitting radionuclides have been studied for the application of the internal radiation theraily. Among them, Holmium-166 has the many beneficial physical characteristics for the internal radiation therapy such as appropriate half life (26.8hr), high ${\beta}$ energy (max. 1.85 MeV(51%), 1.77 MeV (48%), mean 0.67MeV), and low ${\gamma}$ energy (0.081MeV) easily detected by ${\gamma}$-camera. In the internal radiation therapy, the administered radioactive materials should be retained in the target long enough to increase the therapeutic effects and avoid the damage in the normal tissue or organ. For this purpose, radionuclides are used as complex form with carriers. Carriers should have a high affinity with radionuclides in vivo and in vitro, so the complex can be evenly distributed in the lesion but can not be leaked out from the lesion.

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