• Asian-Australasian Journal of Animal Sciences
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• v.13 no.2
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• pp.188-191
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• 2000

Appetite stimulant ether-soluble neutral extract of a high-grain compound feed was separated into four fractions with an open column of silica gel chromatograph using four carrier solutions containing n-pentane and diethyl ether as 100:0 (Fraction A), 90:10 (Fraction B), 75:25 (Fraction C) and 0:100 (Fraction D). The stimulative effects of the fractions were examined by comparing the intake of hay (with or without the fractions) in two-choice test bioassays with cattle. The Fractions A, B and C of the neutral extract stimulated (p<0.05) hay consumption in cattle, whereas Fraction D had no effect on selective feeding when compared with the control fraction. Furthermore, Fractions A, B and C had higher (p<0.05) feeding stimulative indices (FSI) than that of the Fraction D. The results suggest that chemical stimulants to increase palatability of hay are present in the neutral Fractions A, B and C of high-grain concentrate.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.585-589
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• 2007

Gas hydrate is a special kind of inclusion compound that can be formed by capturing gas molecules to water lattice in high pressure and low temperature conditions. When referred to standard conditions, $1m^3$ solid hydrates contain up to $172Nm^3$ of methane gas, depending on the pressure and temperature of production, Such large volumes make natural gas hydrates can be used to store and transport natural gas. In this study, three-phase equilibrium conditions for forming methane hydrate were theoretically obtained in aqueous single electrolyte solution containing 3wt% Nacl. The results show that Nacl acts as a inhibitor, but help gases such as ethan, propane, i-butane, and n-butane reduce the hydrate formation pressure at the same temperature.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3341-3347
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• 2010

A series of oxazolidinone-based strobilurin analogues were efficiently synthesized by the reaction of 3-(2-bromomethylphenyl) oxazolidin-2-one with 1-substituted phenyl-2H-pyrazolin-3-one. Their structures were confirmed and characterized by $^1H$-NMR, $^{13}C$-NMR, elemental analysis, and mass spectroscopy. In addition, the crystal structure of the target compound 3-(2-((1-phenyl-2H-pyrazol-3-yloxy)methyl)phenyl) oxazolidin-2-one was determined by single crystal X-ray diffraction. The bioassay results of these compounds indicated that some of the oxazolidin-2-one derivatives containing N-substituted phenyl 2H-pyrazol ring exhibited potential in vivo fungicidal activities against M. grisea at the dosage of $1\;g\;L^{-1}$.

• Microbiology and Biotechnology Letters
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• v.26 no.2
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• pp.137-142
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• 1998

Helicobacter pylori is a Gram-negative bacterium which causes chronic gastritis and is associated with gastric ulcer, duodenal ulcer and gastric carcinoma. In the process of screening of antibacterial activities against H. pylori from soil microorganisms, fungus No. 60686 was isolated. After fermentation of No.60686, the antibacterial compound was isolated, purified and followed by extraction of mycelium with organic solvents, acetone and ethyl acetate, through silica gel chromatography, LH-20 gel chromatography and HPLC. As a result of the structural analyses of the compound by IR, $^1$H- and $^{13}$C-NMR, FAB/Mass spectrophotometer, the compound having the antimicrobial activity was identified as chaetoglobosin A ($C_{32}H_{36}N_2O_5$), a cytochalasan derivative. The antimicrobial activity of chaetoglobosin A was tested against Gram-positive and negative bacteria by paper disk method. Among the test strains of 9 Gram-positive bacteria and 18 Gram-negative bacteria containing 4 H. pylori strains, the growth of 4 H. pylori strains and 3 S. aureus strains (SG 511, 285 and 503) was only inhibited by chaetoglobosin A. Also it was shown that its growth inhibition against H. pylori strains was stronger than that against S. aureus strains at the treatment of the same concentration. Therefore it was concluded that chaetoglobosin A has a specific growth inhibition against H. pylori of the tested bacteria.

• Journal of the Korean Chemical Society
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• v.52 no.1
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• pp.30-35
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• 2008

purpose of the study was to synthesize new series of 5-cyano substituted pyrimidine analogues with different substitutions at N1 and 6 positions and to evaluate them for antibacterial and antifungal activities. The desired compounds were synthesized by tertiary condensation of ethylcyanoacetate, substituted thioureas and suitable aldehyde in presence of potassium carbonate using MORE technique. The antibacterial and antifungal activities were evaluated by cup plate method in the concentration of 25 mg. The zone of inhibition was measured in mm. All the compounds have shown significant antibacterial and antifungal activities. The maximum activity was shown by P1 and P5 against S.aureus and E.coli respectively, while P6 has shown significant activity against all types of microorganisms. The compound P8 has been found to be significantly effective against C. albicans. Norfloxacin and griseofulvin were used as standards to compare the activites of synthesized compounds. It is concluded that analogues containing p-hydroxy, p-methoxy substituted phenyl moiety at 6 position have been found to be more potent against gram-positive microorganisms, while analogues lacking these substituents on phenyl moiety possessed gram-negative activity. The compounds having p-dimethylamino substituent on phenyl moiety at 6 positions have shown moderate activity. Further, only fluorine containing analogue at N1 position was found to possess appreciable antifungal activity. This suggests that electron donating substituent on aryl moiety as well as electron withdrawing substituent at N1 plays important role in determining potency of the compounds.

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.977-982
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• 2004

The reaction of $cis-[Cr([14]-decane)(OH_2)_2]^+$ ([14]-decane = rac-5,5,7,12,12,14-hexamethyl-1,4,8,11-teraazacyclotetradecane) with auxiliary ligands {$L_a$ = benzoate(bz) or chlorobenzoate(cbz)} leads to a new compound $[Cr([14]-decane)(bz)_2]ClO_4$ or $[Cr([14]-decane)(cbz)_2]ClO_4$. These complexes have been characterized by a combination of elemental analysis, conductivity, IR and Vis spectroscopy, mass spectrometry, and X-ray crystallography. The crystal structure of $[Cr([14]-decane)(cbz)_2]^+$ was determined. The complex shows a distorted octahedral coordination environment with the macrocycle adopting a folded cis-V conformation. The angle $N_{axial}-Cr-N_{axial}$ deviates by $14.5^{\circ}$ from the ideal value of $180^{\circ}$for a perfect octahedron. The bond angle cis-O-Cr-O between the Cr(III) ion and the two carboxylate oxygen atoms of the monodentate p-chlorobenzoate ligands is close to 90$^{\circ}$. The FAB mass spectra of the $cis-[Cr([14]-decane)(La)_2]ClO_4$ display peaks due to the molecular ions $[Cr([14]-decane)(bz)_2-H]^\;,\;[Cr([14]-decane)(cbz)_2-2H]^$ at m/z 578, 646, respectively.

• Bulletin of the Korean Chemical Society
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• v.28 no.1
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• pp.89-94
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• 2007

The new pinane derivative containing unique multifused ring system was synthesized. The crystal, molecular and electronic structure of the title compound has been determined. Both pinane ring systems have the same conformation. The five-membered oxazolidine ring exists in twisted chair conformation. The structure is expanded through O-H…O hydrogen bond to semiinfinite hydrogen-bonded chain. The bond lengths and angles in the optimised structure are similar to the experimental ones. The CH3 and CH2 groups (except this of oxazolidine ring) are negatively charged whereas the CH groups are positively charged. The largest negative potential is on the oxygen atoms. The C-N natural bond orbitals are polarised towards the nitrogen atom (ca. 61% at N) whereas the C-O bond orbitals are polarised towards the oxygen atom (ca. 67% at O). It is consistent with the charges on the nitrogen and oxygen atom of oxazolidine ring and the direction of the dipole moment vector (3.08 Debye).

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.299-307
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• 1996

The surface tension of PO added sodium poly(oxyethylene(EO), oxyisopropylene(PO)) dodecyl ether sulfate firstly were slightly lower than EO added sulfate in the concentration range of $10^{-6}{\sim}10^{-3}mol/{\ell}$. And they had lower critical micelle concentration ($10^{-4}{\sim}9{\times}10^{-5}mol/{\ell}$) than general anionic surfactants. The adsorptivity ($2.2{\times}10^{-10}mol/cm^2$) of sodium $(PO)_{10}(EO)_5$ dodecyl ether(compound of PO addition firstly) calculated by Gibbs' adsorption isotherm were higher than that of sodium $(EO)_{10}(PO)_5$, dodecyl ether(compound of EO addition firstly), but were lower than that of sodium dodecyl sulfate (${\Gamma}=3.2{\times}10^{-10}mol/cm^2$). These could be understood that the adsorption areas of compounds were very large because of their high molecular weight. Moreover, PO compounds showed better properties than EO compounds in foamability, emulsifying power for organics (n-hexane, benzene), detergency for the lard, tallow oil mixture and dispersability for iron oxide. It was interpreted in terms of surface properties of the PO compounds. These showed that the interfacial activity become higher when hydrophilic and hydrophobic portion existed in aggoromerated state respectively. The test results of emulsifying power for organics (n-hexane, benzene) showed better for benzene than n-hexane. Eight kinds of sodium (EO, PO) dodecyl ether derivatives showed irregular dispersibilities for polar iron oxide in water dispersed media.

• Korean Journal of Pharmacognosy
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• v.45 no.1
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• pp.84-87
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• 2014

A high performance liquid chromatography (HPLC) method for the quantitation of ellagic acid in Nymphaea tetragona was developed for the quality control of functional cosmetic ingredient, the extract of N. tetragona. Separation and quantitation were successfully achieved with a Kromasil C18 column ($5{\mu}m$, $250mm{\times}4.6mm$, i.d.) by isocratic elution of a mixture of acetonitrile containing 0.1% trifluoroacetic acid and water containing 0.03% phosphoric acid at a flow rate of 1.0 ml/min. The UV detector was used for the detection and the wavelength for quantitation was set at 254 nm. The presence of ellagic acid in the extract was determined by comparison of retention time and spiking with authentic standard. Analytical results showed good linearity ($R^2=0.99996$) in relatively wide concentration ranges. The R.S.D. for precision test was less than 3.0%. Recovery of the compound was 98.55~101.72% with R.S.D values less than 4.0%. In conclusion, this method has been successfully applied to the determination of ellagic acid in N. tetragona.

• Bulletin of the Korean Chemical Society
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• v.13 no.5
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• pp.531-537
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• 1992

The approximate rates and stoichiometry of the reaction of excess potassium 2-thexyl-1,3,2-dioxaborinane hydride(KTDBNH) with 55 selected compounds containing representative functional groups under standardized conditions (tetrahydrofuran, TEX>$0^{\circ}C$, reagent : compound=4 : 1) was examined in order to define the characteristics of the reagent for selective reductions. Benzyl alcohol and phenol evolve hydrogen immediately. However, primary, secondary and tertiary alcohols evolve hydrogen slowly, and the rate of hydrogen evolution is in order of $1^{\circ}$> $2^{\circ}$> $3^{\circ}$. n-Hexylamine is inert toward the reagent, whereas the thiols examined evolve hydrogen rapidly. Aldehydes and ketones are reduced rapidly and quantitatively to give the corresponding alcohols. Cinnamaldehyde is rapidly reduced to cinnamyl alcohol, and further reduction is slow under these conditions. The reaction with p-benzoquinone dose not show a clean reduction, but anthraquinone is cleanly reduced to 9,10-dihydro-9,10-anthracenediol. Carboxylic acids liberate hydrogen immediately, further reduction is very slow. Cyclic anhydrides slowly consume 2 equiv of hydride, corresponding to reduction to the caboxylic acid and alcohol stages. Acid chlorides, esters, and lactones are rapidly and quantitatively reduced to the corresponding carbinols. Epoxides consume 1 equiv hydride slowly. Primary amides evolve 1 equiv of hydrogen readily, but further reduction is slow. Tertiary amides are also reduced slowly. Both aliphatic and aromatic nitriles consume 1 equiv of hydride rapidly, but further hydride uptake is slow. Analysis of the reaction mixture with 2,4-dinitrophenylhydrazine yields 64% of caproaldehyde and 87% of benzaldehyde, respectively. 1-Nitropropane utilizes 2 equiv of hydride, one for hydrogen evolution and the other for reduction. Other nitrogen compounds examined are also reduced slowly. Cyclohexanone oxime undergoes slow reduction to N-cyclohexylhydroxyamine. Pyridine ring is slowly attacked. Disulfides examined are reduced readily to the correponding thiols with rapid evolution of 1 equiv hydrogen. Dimethyl sulfoxide is reduced slowly to dimethyl sulfide, whereas the reduction of diphenyl sulfone is very slow. Sulfonic acids only liberate hydrogen quantitatively without any reduction. Finally, cyclohexyl tosylate is inert to this reagent. Consequently, potassium 2-thexyl-1,3,2-dioxaborinane hydride, a monoalkyldialkoxyborohydride, shows a unique reducing characteristics. The reducing power of this reagent exists somewhere between trialkylborohydrides and trialkoxyborohydride. Therefore, the reagent should find a useful application in organic synthesis, especially in the field of selective reduction.