• Asian-Australasian Journal of Animal Sciences
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• 제13권2호
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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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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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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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• 제31권11호
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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 $1\;g\;L^{-1}$.

• 한국미생물·생명공학회지
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• 제26권2호
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• pp.137-142
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• 1998

본 실험에서는 만성위염, 위궤양, 십이지장궤양, 위암발생의 원인균으로 알려진 H. pylori를 저해하는 특이항균물질을 생성하는 균주를 토양에서 분리한 방선균액과 곰팡이 추출액을 대상으로 탐색하여 곰팡이 균주번호 60686을 선별하였다. Jar fermentor로 배양하여 얻은 균체를 acetone 및 EtOAc로 추출하였고, 얻어진 추출액을 silica column chromatography와 LH-20 gel chromatography를 수행하여 활성분획을 농축하였고 HPLC를 사용하여 항균 활성을 나타내는 단일물질 IDA를 분리 정제하였다. 항균 활성물질 IDA의 구조를 MS, NMR 분석등을 통해 추정한 결과 곰팡이의 2차 대사산물인 cytochalasan의 전형적 구조를 갖는 분자식 $C_{32}H_{36}N_2O_5$의 chaetoglobosin A라는 물질로 판명되었다. 항균물질 IDA의 항균력을 paper disk법으로 실험한 결과 그람양성 균주중에서는 S. aureus SG 511, 285와 503 3주에서만 항균력을 보였고, 그람음성 균주중에서는 H. pylori 4주에서만 항균력을 보였으나 동일농도 처리시 H. pylori에 대한 항균력이 S. aureus에 비해 우수한 항균효과를 가진다고 판단되었다.

• 대한화학회지
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• 제52권1호
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• pp.30-35
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• 2008

연구의 목적은 N1과 6번 자리에 다른 치환기를 가진 5-cyano가 치환된 pyrimidine 아날로그의 새로운 시리즈의 합성과 그것들의 항균성과 항진균성의 활성도에 대해 평가하기 위해서이다. 이 화합물은 MORE technique 를 이용한 potassium carbonate 의 존재하에서 ethylcyanoacetate, 치환된 thioureas, 적당한 알데히드의 제 3차 축합으로 합성 되어졌다. 항균성과 항진균성의 활성도는 25 mg의 농도에서 cup-plate 방법으로 측정되었다. 억제구역은 mm로 측정 되어졌다. 모든 화합물은 좋은 항균성과 항진균성을 보여주었다. P1과 P5는 S.aureus과 E.coli에 대해 최대 활성도를 보여주었고, P6은 모든 종류의 미생물에 대해 좋은 활성도를 보여주었다. P8 화합물은 C. albicans 에 대해 좋은 효과가 있음을 알아냈다. Norfloxacin와 griseofulvin는 합성된 화합물의 활성도와 비교되는 기준물질로 사용되었다. 6번 자리에 p-hydroxy와 p-methoxy로 치환된 phenyl moiety를 가진 gram-양성 미생물에 대해 강력했고, 6번 자리에 이것들이 없는 phenyl moiety 를 가진 아날로그는 gram-음성 활성도를 가졌다,6번 자리에 p-dimethylamino로 치환된 phenyl moiety를 가진 화합물은 적당한 활성을 보여준다.. 게다가 N1자리에서 단지 fluorine을 포함한 아날로그는 상당한 항진균성을 가졌음을 밝혀냈다. N1자리에서 aryl moiety 의 전자 끌게 치환과 마찬가지로 전자 주게 치환은 화합물의 결정된 능력에 중요한 역할을 함을 제시한다.

• Bulletin of the Korean Chemical Society
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• 제25권7호
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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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• 제28권1호
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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).

• 공업화학
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• 제7권2호
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• pp.299-307
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• 1996

$10^{-6}{\sim}10^{-3}mol/{\ell}$ 농도범위에서 PO가 먼저 부가된 sodium poly(oxyethylene(EO), oxyisopropylene(PO)) dodecyl ether sulfates의 표면장력은 EO가 부가된 화합물보다 낮게 나왔다. 그리고 대체적으로 일반적인 음이온성계면활성제보다도 낮게 나왔다. PO가 먼저 부가된 화합물에 대하여 Gibbs' 흡착등온선으로 계산한 흡착능(${\Gamma}=2.2{\times}10^{-10}mol/cm^2$)은 EO가 부가된 화합물보다는 높지만 sodium dodecyl ether sulfate(${\Gamma}=3.2{\times}10^{-10}mol/cm^2$)보다는 낮다. 이러한 현상은 PO가 부가된 화합물의 분자량이 크기 때문으로 사료된다. 기포력, n-hexane과 benzene에 대한 유화력, 돼지기름과 소기름에 대한 세정력 그리고 산화철에 대한 분산성은 PO 화합물이 EO 화합물보다 우수하게 나타났다. 이러한 현상들은 친수성과 소수성 부분이 각각 따로 따로 존재할 때 계면활성이 높음을 의미한다. 수계에서 n-hexane과 benzene에 대한 유화력 측정결과는 n-hexane보다 benzene에 대하여 높게 나왔으며, 불규칙적인 분산특성을 나타내었다.

• 생약학회지
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• 제45권1호
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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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• 제13권5호
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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.