• Bulletin of the Korean Chemical Society
• /
• v.34 no.7
• /
• pp.2016-2022
• /
• 2013

Ionically modified ${\beta}$-cyclodextrins, which have excellent water-solubility, have been interested in purification technology as well as drug carrier system. The present study summarizes the synthesis and characterization of cationic and anionic ${\beta}$-cyclodextrin (${\beta}$-CyD) products using by polycondensation. The oligo (${\beta}$-CyD)s are synthesized from ${\beta}$-CyD, epichlorohydrin (EP) and choline chloride (CC; for cationic polymer) or chloroacetic acid (CAA; for anionic polymer) through one step polycondenstaion process. Unlike the previous studies, we successfully purified the ionic ${\beta}$-CyD condensation products from the ${\beta}$-CyD reaction mixtures and accomplished a great level of structural analysis. The detailed structural analysis of these ionic ${\beta}$-CyD compounds is done by $^1H$ NMR, MALDI-TOF as well as GPC analysis and confirms the formation of oligomers with a few units of ${\beta}$-CyD. We found that the sequence of reactant addition also could effect on the molecular weight of the resulting product as well as the molar ratio of the reactants. Finally, we used the cationic and anionic ${\beta}$-CyD oligomers for fabricating multilayer films by layer-layer process.

• Applied Chemistry for Engineering
• /
• v.7 no.2
• /
• pp.289-298
• /
• 1996

Eight kinds of poly(oxyethylene, oxyisopropylene) dodecyl ethers were synthesized by adding ethylene oxide and isopropylene oxide with each 5 and 10 moles alternatively on dodecanol. The addition of EO and PO for eight kinds of sodium poly(oxyethylene, oxyisopropylene) dodecyl ether sulfates was identified with HPLC, $^1H$ NMR, hydroxy value, and IR spectrum. In order to verify the sulfation the number of EO and PO molecules was obtained by spectra and Epton method. The yields of products sulfated by chlorosulfonic acid were 90~96%.

• Macromolecular Research
• /
• v.17 no.5
• /
• pp.301-306
• /
• 2009

This work has demonstrated that a novel amphiphilic poly(epichlorohydrine)-graft-polystyrene (PECH-g-PS) copolymer at 34:66 wt% was synthesized via atom transfer radical polymerization (ATRP) of styrene using PECH as a macroinitiator. The structure of the graft copolymer was characterized by nuclear magnetic resonance ($^1H$ NMR) and FTIR spectroscopy, demonstrating that the "grafting from" method using ATRP was successful. The self-assembled graft copolymer was used as a template film for the in-situ growth of silver nanoparticles from $AgCF_3SO_3$ precursor under UV irradiation. The in situ formation of silver nanoparticles with 6-8 nm in average size in the solid state template film was confirmed by transmission electron microscopy (TEM), UV-visible spectroscopy and wide angle X-ray scattering (WAXS). Differential scanning calorimetry (DSC) also displayed the selective incorporation and the in situ formation of silver nanoparticles within the hydrophilic PECH domains, probably due to stronger interaction of the silvers with the ether oxygens of PECH backbone than that with hydrophobic PS side chains.

• Korean Journal of Medicinal Crop Science
• /
• v.13 no.5
• /
• pp.284-287
• /
• 2005

The flowers of Chrysanthemum boreale Makino were extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with n-hexane, EtOAc, n-BuOH and $H_2O$. Two compounds from the n-hexane fraction and one glucoside from the n-BuOH fraction were isolated through the repeated silica gel and ODS column chromatographies. From the result of physico-chemical data including NMR, MS and IR, the chemical structures of the compounds were determined as ${\beta}-sitosterol$ (1), phytol (2) and zingerone $4-O-{\beta}-D-glucopyranoside$ (3). Compounds 2 and 3 were isolated for the first time from this plant.

• Journal of Hydrogen and New Energy
• /
• v.21 no.4
• /
• pp.307-312
• /
• 2010

Poly (ether sulfone)s with Bisphenol-TP and Bisphenol-AF were prepared with Bisphenol-TP <4,4-dihydroxy tetraphenyl methane>, 4-Fluorophenyl sulfone, and Bisphenol-AF <4,4-(hexafluoroisopropylidene) diphenol> using Potassium carbonate in Sulfolane at $210^{\circ}C$. Sulfonated PBTP-AF were obtained by reaction of Chlorosulfuric acid with copolymers. A series of copolymers were studied by $^1H$-NMR spectroscopy, Differential Scanning Calorimeter (DSC), and Thermo Gravimetric Analysis (TGA). Sorption experiments were conducted to observe the interaction of polymers with water and methanol.

• 한국신재생에너지학회:학술대회논문집
• /
• 2008.05a
• /
• pp.243-246
• /
• 2008

목질계 바이오매스 가스화 발전에 있어서는 가스화 가스중에 함유되어있는 타르를 가능한 한 가연성 가스로 전환하여 냉가스효율을 향상시키는 것 및 잔유하는 타르는 후단기기에 악영향을 초래할 우려가 있기 때문에 타르를 저감 제거하는 것이 바람직하다. 본 연구에서는 공기 수증기를 사용하여 타르개질 프로세스의 개선을 위해서 타르에서 가스성분으로의 전환에 관한 개질 실험을 실시하여 Wood chip 타르의 열분해 개질 생성물 거동에 대하여 검토하였다. Wood chip 열분해로 생성된 타르의 원소분석 및 $^1H$ NMR분석의 결과로 타르를 치환기를 가지지 않는 방향족, alkyl-기를 가지는 방향족, 산소 함유 방향족, 지방족의 4개로 분류하였다. 개질제에 의해 경질 타르, 중질 타르 모두 감소하였다. 개질 공기는 타르를 연소시키지만 그 속도는 가연성 가스와 경합하고 $900^{\circ}C$에서는 타르의 연소는 나타나지 않았다. alkyl-기를 가지는 방향족은 메탄과 치환기를 가지지 않는 방향족으로 전환되고, 치환기를 가지지 않는 방향족은 수소와 soot로 전환되고, 산소 함유 방향족은 일산화탄소와 치환기를 가지지 않는 방향족으로 전환되는 것을 알았다. 또한, 개질제에 의해alkyl-기를 가지는 방향족, 치환기를 가지지 않는 방향족, 산소 함유방향족 모두가 일산화탄소,이산화탄소로 전환되는 것을 알았다.

• 한국신재생에너지학회:학술대회논문집
• /
• 2008.05a
• /
• pp.445-447
• /
• 2008

본 연구에서는 다중벽 탄소나노튜브용 표면개질제를 리빙라디칼중합법을 통하여 제조하고, 이를 이용하여 표면개질되고 분산제어된 다중벽탄소나노튜브를 제조하고 염료감응형 태양전지의 대전극 재료로 사용하였다. 우선 리빙라디칼중합법 중 nitroxide mediated polymerization (NMP) 기술을 이용하여 poly(maleic anhydride-co-p-acetoxystyrene)-block-poly(p-acetoxystyrene)를 합성하고, 공중합체중의 maleic anhydride기에 이미드화 반응을 통하여 pyrene기를 도입하였다. 공중합체 중의 p-acetoxystyrene 반복단위들은 가수분해 반응을 통하여 p-hydroxystyrene 반복단위로 변환하였으며, 제조된 공중합체의 구조와 열 특성 등을 GPC, GC, $^1H$-NMR, TGA을 통하여 분석하였다. 제조된 공중합체를 이용하여 다중벽 탄소나노튜브의 표면을 polymer wrapping법으로 처리하였고, 표면개질된 탄소나노튜브의 분산성을 다양한 용매에서 비교분석하였다. 표면이 개질되고 페이스트 내에의 분산성이 향상된 다중벽탄소나노튜브를 염료감응태양전지의 대전극 제조에 응용하였으며, 표면처리 및 분산제어 여부에 따른 제작 특성 및 동작특성 등을 평가하였다.

• Korean Journal of Pharmacognosy
• /
• v.25 no.3
• /
• pp.226-232
• /
• 1994

An antioxidant activity of Gardenia Fruit (Gardenia jasminoides Ellis) which has been used for food coloring was studied. The antioxidant activity was determined by measuring lipid peroxide produced when a mouse liver homogenate was exposed to the air at $37^{\circ}C$, using 2-thiobarbituric acid (TBA). Both water and methanol extracts of Gardenia Fruit showed the antioxidant activity. On solvent fractionation, the antioxidant activity was removed into the ethyl acetate and butanol soluble fractions. And the final water soluble fraction also showed the antioxidant activity in the low concentration, but it promoted the lipid peroxidation in the high concentration. Two compounds (I and II) having the antioxidant activity were isolated from the butanol fraction, and compound I also occurred in the ethyl acetate fraction. The antioxidant activity of compound II was more potent than that of I. By analyzing data for UV, IR and $^1H-NMR$, compounds I and II were identified as geniposide and crocin, respectively.

• Journal of Microbiology
• /
• v.40 no.4
• /
• pp.331-334
• /
• 2002

The substance 0116p, which exhibits cytotoxicity against human macrophage cell line THP-1, was isolated from a mycelial extract of Streptomyces scabiei subsp. chosunensis M0137. The cytotoxic substance was purified by Diaion-HP2O adsorption, solvent extraction, Sephadex LH-20 column chromatography, and silica-gel column chromatography. The molecular formula is C$\_$19/H$\_$38/O$\_$2/ (MW301.10) based on elemental and spectrometric analysis. It was identified as nonadecanoic acid by NMR spectral data. It exhibits cytotoxic activities in various human cancer cell lines, including A549, SK-OV-3, SK-MEL-2 and HCT-15. In addition, 0116p also inhibits IL-12 production in lipopolysaccharide-activated macrophages.

• Journal of Microbiology and Biotechnology
• /
• v.21 no.12
• /
• pp.1236-1242
• /
• 2011

Xanthomonas oryzae pv. oryzae (Xoo) is the most devastating pathogen to Oryza sativa and has been shown to cause bacterial blight. Two bioactive compounds showing antimicrobial activities against Xoo strain KACC 10331 were isolated from a Streptomyces bottropensis strain. The ethyl acetate extract was fractionated on a Sephadex LH-20 column, and then purified by preparative HPLC. The purified compounds were identified as bottromycin A2 and dunaimycin D3S by HR/MS and $^1H$ NMR analyses. The MIC value against Xoo and the lowest concentration still capable of suppressing rice bacterial blight were 2 ${\mu}g$/ml and 16 ${\mu}g$/ml for bottromycin A2, and 64 ${\mu}g$/ml and 0.06 ${\mu}g$/ml for dunaimycin D3S, respectively. These two compounds were shown to exert different bioactivities in vitro and in rice leaf explants.