• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.171-171
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• 1994

Cephem ring의 C-7위치에 aminothiazoly lmethoxyimino기를 가진 화합물들이 항균활성을 증가시키고, G(-)균의 외막투과성을 촉진시킬뿐 아니라 광범위항균 spectrum을 갖게 하고 $\beta$-lactamase에 안정하며 PBP(penicillin binding protein)에 대한 결합친화성을 증가시킨다는 보고에 따라 본 저자는 C-7위치에 cefotaxime구조와 같이 aminothiazolylmethoxyimino acetamido moiety를 고정시키고 항균활성을 증가시키기 위하여 약리활성이 기대되는 5-(substituted)-2H-tetrazole유도체들을 합성하여 C-3 위치에 도입시킨 새로운 화합물 7$\beta$-〔(z)-2-(2-aminothiazol-4-yl)-2_(methoxyimino)acetamido〕-3-〔5-(substituted)tetrazol-2-yl〕 methyl-3-cephem-4-carboxylic acid 유도체를 합성하여 B. subtilis ATCC 6633, M. luteus ATCC 1004, E. coli KCTC 1039, E. coli ESS, K. pncumonia KCTC 1560, P. aeruginosa IF0 13130, S. typhimurium KCTC 1925, S. typhimurium SL 1102, 및 C. albicans ATCC 10231 등의 균과 fungus에 대하여 기존의 cefotaxime과 cefazoline을 대조물질로 사용하여 항균력을 비교하였다. 이들 화합물들은 대체적으로 M. luteus ATCC 6633, E. coli ESS, S. typhimurium SL 1102 균에 대해서는 cefotaxime보다 항균력이 우수하였으나 P. aeruginosa IF0 13130에 대해서는 항균력이 저하되었고 cefazolin보다는 대체적으로 항균력이 우수하였다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.212-212
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• 1994

본 연구소에서 분리하여 항암활성을 측정한바 있는 Sesquiterpene lactone계열의 KR-53170이 in vitro에 비해 in vivo에서 상대적으로 낮은 효력을 보이는데 착안 그 유도체들을 합성함으로써 in vivo stability 및 efficacy를 개선하고자 하였다. 합성된 물질의 in vivo activity는 human tumor cell중에서 A549(폐암), SK-OV-3(난소암1, SK-MEL-2(피부암), XF-498(중추신경계암), HCT-15(직장암)의 5개 암세포를 이용하여 ED$_{50}$($\mu\textrm{g}$/ml )를 측정하였으며 대조물질로는 KR-53170과 Cisplatin이 사용되었다. 그 결과 HR-53170의 terminal methyl ketone이 carboxylic acid로 변환된 CW-251001과 이것의 methyl ester인 CW-251002, ethyl ester인 CW-251003, 그리고 morpheline과 수용성으로 N-methylpiperazine, N-methyl-N'-aminopiperazine, 4-Piperidinopiperidine을 결합시켜서 합성한 CW-251011, CW-251012, CW-251013, CW-251014가 in vitro에서 어느 정도 활성을 유지하였다. 특히 이들중 CW-251001, CW-251012, CW-251013, CW-2s1014는 물에 대한 용해도가 상당히 개선되어 in vivo 활성검색을 위한 후보물질로 고려되었다. 하지만 이들중 CW-251001은 in vivo에서 낮은 농도에서는 활성이 거의 없었으며 놓은 농도에서는 독성을 나타내었다.

• Transactions on Electrical and Electronic Materials
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• v.14 no.3
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• pp.125-129
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• 2013

Composites of platinum and multiwalled carbon nanotubes (MWNTs) were prepared in various reduction conditions and characterized using cyclic voltammetry. The MWNTs were functionalized with carboxylic acid and/or hydroxyl groups in acidic solutions prior to the formation of MWNT-Pt composites. Platinum nanoparticles were deposited onto the chemically-oxidized MWNTs in 1-propanol and 1,3-propanediol. The reduction of Pt precursors in other solutions could induce differences in their morphologies in composite thin films. The morphologies of MWNTs with Pt deposited were dependent on the reduction solutions, and the electrocatalytic activities on alcohols changed accordingly. The electrochemical activities of the as-prepared MWNT-Pt thin films on common alcohols such as methanol and ethanol were investigated.

• Journal of the Korean Magnetic Resonance Society
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• v.3 no.1
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• pp.52-59
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• 1999

Authors synthesized common intermediates which are applicable for potential antibiotics. Their complete 13C and 1H NMR chemical shift data as well as carbon-and proton-fluorine coupling constants are reported. The knowledge of proton and carbon-fluorine coupling constants may help one assign the NMR data of the fluorinated quinolone derivatives. These results agree with the data published previously.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.370.4-371
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• 2002

The roots of Juglans mandshurica Maximowicz (Juglandaceae) have been used as a folk medicine for treatment of cancer in Korea. Several naphthoquinones and naphthalenyl glucosides from Juglans species have been reported (1-7). In the course of isolating cytotoxic compounds from the roots of this plant. we have isolated six naphthalene glycosides. four tetralone, one naphthalene carboxylic acid glucoside and nine diarylheptanoids (8-13). (omitted)

• YAKHAK HOEJI
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• v.41 no.3
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• pp.298-304
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• 1997

Molecular mechanics and conformation search methods were carried oyt to investigate the relationship between conformations and thromboxane synthetase ingibitory activities of om ega-pyridylalkenoic acids. The initial geometries of ${\omega}$-pyridylalkenoic acids and heme part of cytochrome P-450 were obtained from MM+ geometry optimization. The bond lenths and angles were not varied by step during the conformation searching. Stable conformers of some ${\omega}$-pyridylalkenoic acids were obtained by comformational search method. The distances were 8.5~10.8 ${\AA}$- between N atom at 3-position of pyridine ring and C atom at carboxylic group of stable ${\omega}$-pyridylalkenoic acids. The conformations of ${\omega}$-pyridylalkenoic acids and heme part complex were determined by same method. In theses structures, benzene ring and ethylene group in ${\omega}$-pyridylalkenoic acids are making the structure more rigid and increase inhbitory activity. The electron donating groups in C atom shich is connected to pyridine ring also increase activity.

• Bulletin of the Korean Chemical Society
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• v.29 no.1
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• pp.173-176
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• 2008

MJ0684 from Methanococcus jannaschii is a hypothetical protein belonging to the subfamily Ig of amino acid aminotransferases. In the present study, the crystal structure of MJ0684 has been determined at 2.2 resolution. It reveals that MJ0684 has an overall structure similar to subfamily Ig aminotransferases and its active site architecture is most similar to that of kynurenine aminotransferases among several kinds of aminotransferases in the subfamily Ig?. It has two hydrophobic active site residues conserved in the kynurenine aminotransferases for recognizing hydrophobic substrates. In addition, the absence of any basic residue for recognizing the side chain carboxylic group of the aspartate in the active site rules out the possibility that MJ0684 would act as an aspartate aminotransferase. These structural observations collectively imply that MJ0684 is a novel archaeal homolog of the subfamily Ig kynurenine aminotransferase.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.77-80
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• 2006

Graft copolymerized polycarboxylate(PC)-type superplasticizers(PCs) which have carboxylic acid with $\pi$ bond among the molecular structure and polyethyleneglycol methyl ether methacrylate(PMEM) were synthesized by free radical reaction and investigated the chemical structure, polymerization condition, and physical and chemical properties. Also, the effects of PCs in the dispersion, adsorption and hydration of cement were evaluated. As the molecular weight of graft chain decreases, the adsorption amount on cement particles increased. It was advantageous for the flow to reduce molar ratio, the lower the side bone molecular weight, and increase the molar ratio, the larger the side bone molecular weight. The hydration reaction speed was highly delayed at day 1, due to increase in molar ratio and reduction in side bone molecular weight, but it was recovered in the days after.

• Molecules and Cells
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• v.38 no.7
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• pp.597-603
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• 2015

Biosynthesis of the phytohormone ethylene is under tight regulation to satisfy the need for appropriate levels of ethylene in plants in response to exogenous and endogenous stimuli. The enzyme 1-aminocyclopropane-1-carboxylic acid synthase (ACS), which catalyzes the rate-limiting step of ethylene biosynthesis, plays a central role to regulate ethylene production through changes in ACS gene expression levels and the activity of the enzyme. Together with molecular genetic studies suggesting the roles of post-translational modification of the ACS, newly emerging evidence strongly suggests that the regulation of ACS protein stability is an alternative mechanism that controls ethylene production, in addition to the transcriptional regulation of ACS genes. In this review, recent new insight into the regulation of ACS protein turnover is highlighted, with a special focus on the roles of phosphorylation, ubiquitination, and novel components that regulate the turnover of ACS proteins. The prospect of cross-talk between ethylene biosynthesis and other signaling pathways to control turnover of the ACS protein is also considered.

• YAKHAK HOEJI
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• v.54 no.6
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• pp.466-473
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• 2010

A series of $3{\beta}$-substituted 5-androstene-$17{\beta}$-carboxamides were synthesized from analogs of $3{\beta}$-hydroxy-5-androstene-$17{\beta}$-carboxylic acid (1) with tert-butylamine, N,N-diethylamine and 3-aminopyridine and some compounds were epoxidized with mCPBA. A rat prostate testosterone $5{\alpha}$-reductase inhibitory activity of synthesized compounds was assessed by radioimmunoassay using [1,2,6,7-3H]-testosterone as substrate. All synthesized compounds showed lower activity than finasteride and the N-(3-pyridino)-$3{\beta}$-carboxycarbonyloxy-5-androstene-$17{\beta}$-carboxamide (12) showed weak inhibitory activity ($IC_{50}$: $2.4{\times}10^{-7}M$).