• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1784-1786
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• 2011

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.1085-1087
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• 2004

• Bulletin of the Korean Chemical Society
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• v.32 no.6
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• pp.2070-2072
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• 2011

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3366-3368
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• 2014

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2529-2530
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• 2011

• YAKHAK HOEJI
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• v.7 no.1
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• pp.8-12
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• 1963

The piperazine salts with 24 kinds of phenols and 6 kinds of organic carboxylic acids were prepared. The test of anthelmintic effect against Ascaris suilla, in vitro, for Hexachlorophene-piperazine salt, Bithionol-piperazine salt, Kainic acid-piperazine salt were also carried out compared with piperazine, Hexachlorophene, Bithionol and Kainic acid.

• Bulletin of the Korean Chemical Society
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• v.10 no.6
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• pp.547-551
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• 1989

1-Methoxypyrrole-2-carboxylic acid and its derivatives were prepared. Fridel-Crafts bromination occurs first at 4-position and then at 5-position. Acylation of 3-methyl derivative was also directed to 4-position.

• Journal of the Korean Chemical Society
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• v.19 no.4
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• pp.280-285
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• 1975

The degradation mechanisms of naphthoquinone-1,2-diazide-5-sulfonyl esters(PGND, BEND and PVAND) of polyglyceryl phthalate (PG), bisphenol A-epichlorohydrin (BE) and polyvinyl alcohol (PVA) were studied by infrared absorption spectra. Absorption band due to C=N=and C=O of o-quinonediazide group decreased or disappeared after sufficient exposing to light. And also, absorption band C=O of indene carboxylic acid was increased. From the results, it may be concluded that the above photosensi tive polymers were dissociated to indene carboxylic acid soluble in aqueous alkali solution. Further, the effect of sensitizers were examined by the variation of intensity in infrared absorption spectra of sensitized and unsensitized samples.

• Journal of the Korean Chemical Society
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• v.38 no.10
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• pp.749-752
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• 1994

Two furanosesquiterpenes, (5'E)-5-(2',6'-dimethylocta-5',7'-dienyl) furan-3-carboxylic acid (1) and (1'E,5'E)-5-(2',6'-dimethylocta-l',5',7'-trienyl) furan-3-carboxylic acid (2), were isolated from soft coral Sinularia lochmodes collected from Palikir pass at Pohnpei Micronesia, June, 1990 in Hawaii. Their structures were elucidated by $^1H$, $^{13}C$ NMR, Homo-COSY, $^1H$-$^{13}C$ (1 bond) Heteronuclear Multiple Quantum Coherence Spectroscopy (HMQC), $^1H$-$^{13}C$ (2 and 3 bond) Heteronuclear Multiple Bond Coherence Spectroscopy (HMBC), Electron Impact Mass Spectroscopy (EI-ms), and Infrared Spectroscopy (IR).

• Microbiology and Biotechnology Letters
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• v.22 no.6
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• pp.636-642
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• 1994

Essential amino acids involving in the catalytic mechanism of the $\beta$-D-xylosidase of Bacillus stearothermophilus were determined by chemical modification studies. Among various che- mical modifiers tested N-bromosuccinimide (NBS), $\rho$-hydroxymercurybenzoate (PHMB), N-ethylma- leimide, 1-[3-(di-ethylamino)-propyl]$-3-ethylcarbodi-imide (EDC), and Woodward's Reagent K(WRK)inactivated the enzyme, resulting in the residual activity of less than 20%. WRK reduced the enzyme activity by modifying carboxylic amino acids, and the inactivation reacion proceeded in the form of pseudo-first-order kinetics. The double-lagarithmic plot of the observed pseudo-first- order rate constant against the modifier concentration yielded a reaction order of 2, indicating that two carboxylic amino acids were essential for the enzyme activity. The $\beta$-D-xylosidase was also inactivated by N-ethylmaleimide which specifically modified a cysteine residue with a reaction order of 1, implying that one cysteine residue was important for the enzyme activity. Xylobiose protected the enzyme against inactivation by WRK and N-ethylmaleimide, revealing that carboxylic amino acids and a cysteine residue were present at the substrate-binding site of the enzyme molecule.