• 제목/요약/키워드: Carboxylic Acid

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Adsorption of Cu(II) from Aqueous Solutions Using Pinus densiflora Wood (Pinus densiflora 목질을 이용한 수용액 중의 Cu(II) 흡착)

  • Park, Se-Keun;Kim, Ha-Na;Kim, Yeong-Kwan
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.1
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    • pp.27-36
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    • 2007
  • Milled Korean pine (Pinus densiflora) wood was used to evaluate its adsorption capacity of Cu(II) ions from aqueous solution by running a series of batch experiments. Prior to the tests, the milled woods were pretreated with 1N NaOH, 1N $NHO_3$, and distilled water, respectively, to examine the effect of pretreatment. Within the tested pH range in this study between 3 and 6, copper adsorption efficiency of NaOH-treated wood(96~99%) was superior than $NHO_3$-treated wood(19~31%) and distilled water-treated wood(18~35%). Adsorption behavior of copper onto both raw and $NHO_3$-treated woods was mainly attributed to interaction with carboxylic acid group. For NaOH-treated wood, carboxylate ion produced by hydrolysis was a major functional group responsible for Cu sorption. NaOH treatment of wood changed the ester and carboxylic acid groups into carboxylate group, whereas $NHO_3$ treatment did not affect the production of functional groups which could bind copper. A pseudo second-order kinetic model fitted well for the sorption of copper ion onto NaOH-treated wood. A batch isotherm test using NaOH-treated wood showed that equilibrium sorption data were better represented by the Langmuir model than the Freundlich model.

Purification and the Stoichiometry of Nucleoside Oxidase from Flavobacterium meningosepticum (Flavobacterium meningosepticum이 생산하는 Nucleoside Oxidase의 정제 및 Stoichiometry)

  • 최양문;조홍연;양한철
    • Microbiology and Biotechnology Letters
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    • v.21 no.1
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    • pp.23-29
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    • 1993
  • A bacterial strain. producing a nucleoside oxidase was isolated from soil and identified as Flavobacterium meningosepticum by its taxonomical characteristics. The enzyme has been purified ISO-fold to electrophoretic homogeniety in an overall yield of 18% from the cell free extract of the producer. The enzyme catalyzed oxidation of only nucleosides related to both purine and pyrimidine with very high substrate specificity. The nucleoside oxidase was proved to be a noble enzyme by stoichiometry that 1 mol adenosine as a substrate was especially oxidized via adenosine 5' -aldehyde to 1 mol adenosine 5' -carboxylic acid with the formation of 2 mol $H_20_2$

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Elucidation of Antifungal Metabolites Produced by Pseudomonas aurantiaca IB5-10 with Broad-Spectrum Antifungal Activity

  • Park, Gwee-Kyo;Lim, Jong-Hui;Kim, Sang-Dal;Shim, Sang-Hee
    • Journal of Microbiology and Biotechnology
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    • v.22 no.3
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    • pp.326-330
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    • 2012
  • Antifungal metabolites were isolated from a culture of Pseudomonas aurantiaca IB5-10. Chemical structures of the metabolites were elucidated as phenazine-1-carboxylic acid (PCA; 1), 2-hydroxyphenazine (2-OH-PHZ; 2), and cyclo-(L-Pro-L-Val; 3), respectively, based on spectroscopic methods. Among them, 3 was isolated for the first time from this strain. The antifungal activities of 1-3 were evaluated against a variety of plant pathogens. To the best of our knowledge, the antifungal activities of 3 against plant fungal pathogens have been evaluated for the first time in this work. PCA (1) showed the most potent antifungal activities against Phytophthora capsici, Rhizoctonia solani AG-1(IA), and Pythium ultimum with MICs (${\mu}g/ml$) of less than 1.0, 1.3, and 2.0, respectively. On the other hand, 2-OH-PHZ (2) showed potent antifungal activity against R. solani AG-1(IA) with the MIC (${\mu}g/ml$) of 2.0, whereas it showed moderate antifungal activity against P. ultimum with the MIC (${\mu}g/ml$) of 50.0. In addition, 3 showed antifungal activity against only R. solani AG-1(IA).

Development of Novel Pyrone Derivative Retaining Retinoidal Anti-aging Activity with Low Skin Irritation

  • Rho, H.S;Kim, D.H;Kim, S.N;Kim, S.J;Chang, I.S;Kang, H.H;Lee, O.S
    • Proceedings of the SCSK Conference
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    • 2003.09b
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    • pp.184-191
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    • 2003
  • New pyranone derivative, 2-((3E)-4(2H, 3H, -benzo[3, 4-d] 1, 3-dioxolan-5-yl)-2-oxo-but-3-enyloxy)-5-hydroxy-4H-pyran-4-one (Seletinoid $G^{TM}$), was designed as a novel retinoid on the assumption that the pyranone ring may mimic the carboxylic acid moiety in retinoid structure. The enolic hydroxy of pyranone at five position was easily deprotonated to form an enolate. The role of enolate was similar to that of carboxylic acid. To evaluate the value of Seletinoid G as an anti-aging ingredient, various tests were performed for example inhibitory effect for MMP-l expression, anti-oxidative activity, procollagen synthesis in hairless mouse and primary skin irritation. The result of this study suggested that our new synthetic retinoid could be used as a safe material for anti-aging cosmetics.

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Studies on the Cytotoxic Constituent of Saururus chinensis$(L_{OUR.})\;B_{AILL.}$ (삼백초의 세포독성 성분연구)

  • Park, Si-Kyung;Oh, Gab-Jin;Bae, Choon-Il;Kim, Hyun-Jong;Han, Wan-Sik;Chung, Sun-Gan;Cho, Eui-Whan
    • YAKHAK HOEJI
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    • v.41 no.6
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    • pp.704-708
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    • 1997
  • In our search for bioactive natural products with antitumor activity, we have valuated various extracts of Saururi Herba (Saururaceae), which has been used in traditional medici ne for edema, beriberi, jaundice, turbid urine, carbuncle and furuncle. The hexane extract of the aerial part of this plant was found to show a potent cytotoxicity against several kinds of cultured human solid tumor cell lines (AGS, A549, HCT15, SKOV3, HEP-3B) in vitro. Using cytotoxicity-guided chromatographic separation of the hexane extract, cytotoxic constituent: 10-aminomethyl-3-hydroxy-4-methoxyphenanthrene-carboxylic acid lactam, was isolated and structurally identified by physico-chemical properties and spectroscopic evidences.

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1H-NMR and HPLC analysis on the chiral discrimination of β-blockers using (S)-2-tert-butyl-2-methyl-1,3-benzodioxole-4-carboxylic acid

  • Seo, Sang Hun;Mai, Xuan-Lan;Le, Thi-Anh-Tuyet;Kim, Kyeong Ho
    • Analytical Science and Technology
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    • v.34 no.1
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    • pp.9-16
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    • 2021
  • In the group of commonly prescribed β-blocker drugs, one of the enantiomers is generally relatively more active than the others. This study aims to develop a technique for the chiral analysis of select β-blockers based on proton nuclear magnetic resonance (1H-NMR) spectrometry. (S)-2-Tert-butyl-2-methyl-1,3-benzodioxole-4-carboxylic acid ((S)-TBMB) was synthesized and utilized as a chiral derivatizing agent. Pure β-blocker enantiomers were isolated from racemates by semi-preparative liquid chromatography prior to derivatization. The reaction time and concentration of (S)-TBMB were controlled to improve the derivatization procedure. No racemization was found during the analysis. High-performance liquid chromatography (HPLC) analysis was also performed for comparative purposes. High agreement between the NMR and HPLC methods was achieved in the determination of (R)-metoprolol in a standard solution of the (S) isomer.

The Synthesis of 6-Fluoroquinolone Carboxamidopenicillin Derivatives (6-Fluoroquinolone Carboxamidopenicillin 유도체의 합성)

  • 임철부;김정주
    • YAKHAK HOEJI
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    • v.31 no.2
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    • pp.92-97
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    • 1987
  • The N-[1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroquinoline-3-carboxy] succinimide was reacted with amoxicillin, ampicillin and 6-APA to give 6-[D-(-)-$\alpha$-{1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroguinoline-3-carboxamido} p-hydroxyphanyl acetamido] penicillanic acid [1], 6-[D-(-)-$\alpha$-{1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroquinoline-3-carboxamido} phenylacetamido] penicillanic acid [10] and 6-[1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroquinoline-3-carboxamido] penicillanic acid [19]. The 1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxylic acids were reacted with ethyl chloroformate for making mixed anhydride; these mixed anhydrides were reacted with amoxicillin, ampilcillin and 6-APA to give 6-[D-(-)-$\alpha$-{1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxamido} p-hydroxyphenylacetamido] penicillanic acid [2-9], 6-[D-(1)-$\alpha$-{1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxamido} phenylacetamidod penicillanic acid [11-18] and 6-[1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxamido] penicillanic acid [20-27].

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Explorative and Mechanistic Studies of the Photooxygenation of Sulfides

  • Albini, Angelo;Bonesi, Sergio M.
    • Journal of Photoscience
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    • v.10 no.1
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    • pp.1-7
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    • 2003
  • The results of recent work on the dye-sensitized photooxygenation of sulfides is discussed. In the case of dialkyl sulfides, the weakly bonded adduct initially formed with singlet oxygen (the persulfoxide) decays unproductively unless protonation by an acid (an alcohol or a carboxylic acid) facilitates its conversion to the sulfoxide. The effect is proportional to the strength of the acid (eg., less than 0.1 % chloroacetic acid in benzene is sufficient for maximal efficiency) and corresponds to general acid catalysis, suggesting that protonation of the persulfoxide occurs. On the other hand, with sulfides possessing an activated hydrogen in ${\alpha}$ position (eg., benzyl and allyl sulfides), hydrogen transfer becomes an efficient process in aprotic media and yields a S-hydroperoxysulfoniumm ylide, possibly arising from a conformation of the persulfoxide that is different from the one protonated in the presence of acids. Calculations on some substituted sulfides support this hypothesis. This process, which leads to C-S bond fragmentation with formation of an aldehyde, may be viewed as a general method for the preparation of aryl and heteroaryl aldehydes. In this effort, mechanistic studies offered new hints on the structure of the intermediate persulfoxide.

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FTIR study of E7 liquid crystals confined to perfluorinated carboxylic acid treated cylindrical cavities of Anodisc membranes

  • Ha, Ki-Ryong;Ahn, Hee-Jun;Yoon, Sung-Kyoun;Lee, Dong-Ho;West, John L.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.369-372
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    • 2004
  • Orientation of E7 liquid crystals(LCs) confined to 200 nm-diameter cylindrical cavities of Anodisc membranes are investigated by FTIR dichroism techniques. The cavity walls of the confining pores are chemically modified with different perfluorinated carboxylic acids (PCA, $C_nF_{2n+1}$COOH, n=3, 4, 5, 6). From the FTIR spectra of PCA treated alumina Anodsic membranes, we found the salt formation between -COOH group of PCA and Anodisc membrane. From the FTIR spectra of LC filled Anodisc membranes, we found abrupt alignment direction change of LC molecules between n=4 and 5 for 1 mM PCA treated Anodisc membranes, from parallel to perpendicular direction to the cavity walls. But 5mM PCA treated Anodisc membranes, alignment direction of LC molecules changed between n=3 and n=4, from parallel to perpendicular direction.

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Synthesis and Antimicrobial Activities of Thiocarbamyl Enoxacin Derivatives (Thiocarbamyl Enoxacin 유도체의 합성 및 항균작용)

  • 신화우;고무수;정동훈;최광식;임철부
    • YAKHAK HOEJI
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    • v.35 no.5
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    • pp.353-359
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    • 1991
  • Treatment of 1-ethyl-6-fluoro-1, 4-dihydro-4-oxo-7-(l-piperazinyl)-I, 8- naphthyridine-3-ca rboxylic acid (Enoxacin) with alkyl(or aryl) isothiocyanates which obtained from alkyl(or aryl) amines afforded six 1-ethyl-6-fluoro-1, 4-dihydro-4-oxo-7-(1-alkylthiocarbamylpiperazinyl)-1, 8- naphthyridine-3-carboxylic acids and five 1-ethyl-6-fluoro-1, 4-dihydro-4-oxo-7-(l-arylthiocarbamyl piperazinyl)-1, 8-naphthyridine-3-carboxylic acids. The compounds synthesized were evaluated for their antimicrobial activities, in vitro, against Escherichia coli 6-PE-4, Bacillus subtilis 74-51, Proteus vulgaris 78645, Klebsiella pneumoniae JYA-78314, Staphylococcus aureus 79110 and Pseudomonas aeruginosa 8765-1 P$_{2}$.

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