• ETRI Journal
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• 제26권6호
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• pp.647-652
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• 2004

A new ionic liquid, 1-vinyl-3-heptylimidazolium iodide (VHpII), was synthesized and applied as a redox electrolyte for dye-sensitized solar cells. The chemical structure of the synthesized VHpII was confirmed using $^1H$ NMR. Thermogravimetric analysis showed that the VHpII was stable for thermal stress of up to $250^{\circ}C$. The energy conversion efficiencies of the VHpII-based dye-sensitized solar cells were investigated in terms of the effect of a lithium iodide addition. A solar cell containing the redox couple of VHpII and iodine showed a conversion efficiency of 2.63% under 1 sun light intensity at AM 1.5. Adding 0.4 M LiI results in a conversion efficiency of 3.63%, which was an improvement of about 40%. The increased conversion efficiency was ascribed to an increase in external quantum efficiency.

• Archives of Pharmacal Research
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• 제28권6호
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• pp.657-659
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• 2005

A new biflavonol glycoside named as solanoflavone (1) was isolated from aerial part of Solanum melongena. The chemical structure was elucidated as isorhamnetin-3-O-$\beta$-D-glucopyranoside-(4'$\to$O$\to$4"')-galangin-3"-O-$\to$-D-glucopyranoside on the basis of physicochemical and spectroscopic methods, including 2D NMR spectral techniques.

• 통합자연과학논문집
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• 제2권2호
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• pp.78-81
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• 2009

In recent years, organometallic polymer containing silane and silole unit has been a topic of interest because of the wide range of optical, electrical and luminescent properties. In previous work, we synthesized functionalsilanebridged[1]ferrocenophane from the reaction of dimethyldichlorosilane[Me2SiCl2] and diphenyldichlorosilane[Ph2SiCl2] and dichloromethylvinylsilane[C3H6SiCl2] with ferrocene$[Fe({\eta}-C5H4)2]$ and n-BuLi. In this work, we have synthesized Poly(ferrocenylsilane) via the Thermal Ring-Opening Polymerization(ROP). characteristics of the poly(ferrocenylsilane) were investigated by gel permeation chromatography(GPC), 1H- and 13C-NMR spectroscopy.

• Archives of Pharmacal Research
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• 제29권11호
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• pp.963-968
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• 2006

Seven phenolic compounds (1-7) were isolated from the tubers of Gastrodia elata. Their structures were elucidated on the basis of MS and NMR spectral data. p-Ethoxymethyl phenyl-O-${\beta}$-D-glucoside (1) was proved to be a new compound, with N-(p-hydroxybenzyl)-adenosine (7) isolated from this plant for the first time. In this study, the protective effects of the six constituents (1-6) on PC12 cells against the cytotoxicity induced by KCI and glutamate were also investigated. The viability of the PC12 cells was significantly enhanced by pretreatment with the six phenolic constituents.

• 생약학회지
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• 제42권3호
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• pp.223-228
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• 2011

Chaenomeles sinensis Koehne (Rosaceae) is a deciduous tree and is distributed in China, Korea and Japan. In previous studies on the fruits of C. sinensis, some triterpenoid compouds such as oleanolic acid, tormentic acid were reported. In an ongoing investigation into biologically active compounds from natural products, the methanol extract of the stems of C. sinensis was investigated. By means of the repeated column chromatography using silica gel, Sephadex LH-20, LiChroprep RP-18, betulin (1), tormentic acid (2), 1-${\beta}$-D-glucopyranosyl-3,4,5-trimethoxybenzene (3), lyoniresinol-2a-O-${\alpha}$-L-rhamnopyranoside (4) were isolated. The chemical structures of compounds 1-4 were determined by the basis of physico-chemical properties and spectroscopic methods such as 1D and 2D NMR. For the isolated compounds (1-4), the inhibitory activity of IL-6 production in TNF-${\alpha}$ stimulated MG-63 cell was examined. Among the isolates, betulin (1), 1-${\beta}$-D-glucopyranosyl-3,4,5-trimethoxybenzene (3), lyoniresinol-2a-O-${\alpha}$-L-rhamnopyranoside (4) showed inhibitory effects on IL-6 production in TNF-${\alpha}$ stimulated MG-63 cell.

• 한국결정학회지
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• 제16권1호
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• pp.43-53
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• 2005

알칸화합물(alkanes)에서 탄소-수소결합을 활성화시켜서 더욱 값이 비싸고 더 유용한 알켄화합물(alkenes)로 만들 수 있는 촉매를 만들고자 지난 수 십 년간 많은 화학자들이 연구해왔다 이러한 목적의 하나로서 두개의 수소를 가지는 이리디움 P-C-P핀서(pincer) 착물 $(IrH_2{C_6H_3-2,6-(CH_2PBu_2^t)_2})$을 성공적으로 합성하였다. 이 착물은 알칸의 탈수소화반응(dehyrogenation)에 아주 효과적인 촉매로 알려졌다 알칸의 탈수소화반응에 촉매독으로 작용하는 질소, 물, 이산화탄소 및 일산화탄소와 같은 작은 화합물들과 직접 반응시켜서 어떻게 촉매독으로 작용하는지를 알아봤다. 촉매독으로 작용할 수 있는 화합물들을 합성하여 핵자기공명분광법(NMR)과 적외선분광법(IR)으로 확인하였고 분자구조를 알아보기 위해서 단결정X-ray 회절법을 통하여 확인하였다. 본 논문에서는 촉매 및 촉매독물질의 합성과 분자구조와 각각의 화합물의 반응성과 특이성을 알아보았다.

• Bulletin of the Korean Chemical Society
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• 제34권6호
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• pp.1791-1794
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• 2013

Phytochemical investigation on dragon's blood of Dracaena cambodiana led to the discovery of two new flavonoid derivatives, cambodianin G (1) and cambodianin H (2). Their structures were elucidated on the basis of detailed spectroscopic analysis, including 1D and 2D NMR techniques and chemical methods. The two compounds were observed to exhibit antibacterial activities against Staphylococcus aureus, and compound 1 showed cytotoxicities against K562 and SGC-7901 cell lines.

• Bulletin of the Korean Chemical Society
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• 제35권6호
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• pp.1647-1653
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• 2014

9,10-Bis(bromomethyl)phenanthrene reacted with fullerenes via a Diels-Alder reaction to give phenanthrene-substituted fullerene mono-adducts (PCMA) and bis-adducts (PCBA) as electron acceptors for organic photovoltaic cells (OPVs). The syntheses of the fullerene derivatives were confirmed by $^1H$ $^{13}C$ NMR spectroscopy and MALDI-TOF mass spectrometry. PCMA and PCBA showed better light absorption in the UV-visible region than $PC_{61}BM$. Their electrochemical properties were measured using cyclic voltammetry. Accordingly, the lowest unoccupied molecular orbital (LUMO) energy levels of PCMA and PCBA were -3.66 and -3.57 eV, respectively. Photovoltaic cells were fabricated with a ITO/PEDOT:PSS/poly(3-hexylthiophene)(P3HT):acceptor/LiF/Al configuration, where P3HT and PCBA are the electron donors and acceptors, respectively. The polymer solar cell fabricated using the P3HT:PCBA active layer showed a maximum power conversion efficiency of 0.71%.

• Natural Product Sciences
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• 제15권2호
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• pp.71-75
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• 2009

The great economic and social damage caused by unusual explosion of jellyfish population has attracted the attention of researchers. A chemical study on the bioactive components of the giant jellyfish Nemopilema nomurai led to the isolation of two new (1 and 2) and three known alkoxyglycerols (3 - 5), along with known monoglycerides (6 - 7) and fatty acids. Based on NMR and MS data, the structures of compounds 1 and 2 were elucidated as 1-O-[(Z)-tetradec-3-enyl]-sn-glycerol and 1-O-[(Z)-octadec-10-enyl]-sn-glycerol, respectively. The absolute configurations of compounds 1 - 7 were determined by comparison of specific optical rotation values with those reported. The isolated compounds were evaluated for suppressive effect on the proinflammatory mediators (NO, IL-6, and TNF-${\alpha}$) in murine macrophage cells. However, they were found inactive upto the concentration of 100 ${\mu}M$.

• Bulletin of the Korean Chemical Society
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• 제28권8호
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• pp.1299-1304
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• 2007

New sulfur functionalized cyclopentadiene ligands, 1-[2-(thioanisole)]-2,5-dimethylcyclopentadiene (3), 1-[2- (thioanisole)]-2,3,5-trimethylcyclopentadiene (4), and 1-[2-(thioanisole)]-2,3,4,5-tetramethylcyclopentadiene (5), were prepared. In these ligands, the S-donor atom is connected to a cyclopentadiene ring by a rigid phenylene spacer. CpCo(III)-diiodo half-sandwich complexes (6-8) were obtained from reaction the ligands (3- 5) with Co2(CO)8, followed by treatment of I2. Substitution reaction of CpCo(III)-diiodo complexes with MeLi yielded the corresponding CpCo(III)-dimethyl complexes (9-11). Further transformation to the corresponding cationic cobalt complexes (12-14) were achieved by reaction of the CpCo(III)-dimethyl complexes with HB(ArF)4·2Et2O and trapping with CD3CN. The new sulfur functionalized cyclopentadiene ligands having a rigid phenylene spacer and the corresponding cobalt complexes were characterized by 1H, 13C and 19F NMR spectroscopy. The diiodo Complex 6 was also characterized by a single crystal X-ray diffraction method.