• Bulletin of the Korean Chemical Society
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• 제17권6호
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• pp.502-506
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• 1996

Several ester group-containing calix[4]arenes were synthesized by the reaction of calix[4]arene and various acyl chlorides. Two or four ethyl succinyl units could be introduced into the calix[4]arene lower rim depending on the reaction conditions. But the mixture of three and four ethyl malonyl substituted calix[4]arenes were obtained and only three ethyl oxalyl units were introduced at the lower rim of calix[4]arene. Interestingly when calix[4]arene was treated with ethyl oxalyl chloride in the presence of aluminum chloride, two ethyl oxalyl units were introduced at the upper rim of calix[4]arene. The conformation of those ester-containing calix[4]arenes was presented based on the 1H and 13C NMR spectra.

• Molecules and Cells
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• 제26권2호
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• pp.206-211
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• 2008

HI0381 of Haemophilus influenzae was investigated by circular dichroism (CD) and nuclear magnetic resonance (NMR) spectroscopy. HI0381 is a 153-residue peptidoglycan-associated outer membrane lipoprotein, and a part of the larger Tol/Pal network. Here, we report its backbone $^1H$, $^{15}N$, and $^{13}C$ resonance assignments, and secondary structure predictions. About 97% of all of the $^1HN$, $^{15}N$, $^{13}CO$, $^{13}C{\alpha}$, and $^{13}C{\beta}$ resonances covering 131 non-proline residues of the 134 residue, mature protein, were clarified by sequential and specific assignments. CSI and TALOS analyses revealed that HI0381 contains five ${\alpha}$-helices and five ${\beta}$-strands. To characterize the structure of HI0381, the effects of pH and salt concentration were investigated by CD. In addition, the structural changes occurring when HI0381 was in a membranous environment were investigated by comparing its HSQC spectra and CD data in buffer and in DPC micelles; the results showed that helix ${\alpha}4$ and strand ${\beta}4$ became aligned with the membrane. We conclude that the conformation of HI0381 is affected by the membrane environment, implying that its folded state is directly related to its function.

• Applied Biological Chemistry
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• 제50권3호
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• pp.178-186
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• 2007

항균균활성이 있는 4-isopropylphenol(I)과 2-isopropylphenol (II)을 출발물질로 하여 ester, sulfonyl ester, phosphoyl ester와 ether계열 유도체 42종을 합성하였으며, 확인은 IR, $^{1}H-NMR$과 GC/MS를 이용하였다. 이들 유도체들에 대한 in vitro 항균활성 실험을 오이탄저병균(Colletotrichum orbiculare) 외 9종에 대하여 실시하였다. 그 결과, 2-isopropylphenyl piperonyloate(II-7a)가 오이탄저병균(Colletotrichum orbiculare)과 토마토잎마름병균(Phytophthora infestans)에 효과가 있었으며, 4-isopropylphenyl bromoacetate(I-3a)가 오이잿빛곰팡이병균(Botrytis cinerea), 4-isopropylphenyl-4-methoxybenzenesulfonate(I-6b)는 벼도열병균(Pycularia oryzae)에 탁월한 효과를 나타내었으며, 4-isopropylphenylbenzyl ether(I-4d)가 오이탄저병균(Colletotrichum orbiculare)에 우수한 효과를 나타내었다. In vivo 실험에서는 2-isopropylphenyl piperonyloate(II-7a)가 오이탄저병(Colletotrichum orbiculare)과 토마토잎마름병(Phytophthora infestans), 4-isopropylphenyl 4-methoxybenzenesulfonate(I-6b)가 벼도열병(Pycularia oryzae)에 매우 우수한 항균활성을 나타내었다.

• Applied Biological Chemistry
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• 제43권4호
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• pp.298-302
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• 2000

식용버섯 유래의 저분자 대사산물을 탐색하던 중 충남 계룡산 일대에서 채집한 능이버섯(Sarcodon aspratus)으로부터 7종의 화합물을 분리하였다. 능이버섯을 메탄올에 추출한 후 용매분획하여 그 중 화합물이 많이 함유된 chloroform층과 ethyl acetate층에 대하여 각각 silica gel 및 Sephadex LH-20 column chromatography를 수행하였다. 주요 대사산물을 함유하고 있는 분획물을 TLC 및 분취용 HPLC를 사용하여 최종적으로 정제하여 7종의 화합물을 분리하였다. 이들 화합물은 $^1H\;NMR$, mass 분석 및 문헌 data와 비교하여 각각 4-hydroxybenzoic acid methyl ester, 4-hydroxybenzaldehyde, cyclo(Ala-Pro), adenosine, nicotinamide, BL V, linoleic acid으로 동정되었다.

• Archives of Pharmacal Research
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• 제29권8호
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• pp.712-719
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• 2006

In this study, we prepared core-shell type nanoparticles of a poly(DL-lactide-co-glycolide) (PLGA) grafted-dextran (DexLG) copolymer with varying graft ratio of PLGA. The synthesis of the DexLG copolymer was confirmed by $^1H$ nuclear magnetic resonance (NMR) spectroscopy. The DexLG copolymer was able to form nanoparticles in water by self-aggregating process, and their particle size was around $50\;nm{\sim}300\;nm$ according to the graft ratio of PLGA. Morphological observations using a transmission electron microscope (TEM) showed that the nanoparticles of the DexLG copolymer have uniformly spherical shapes. From fluorescence probe study using pyrene as a hydrophobic probe, critical association concentration (CAC) values determined from the fluorescence excitation spectra were increased as increase of DS of PLGA. $^1H-NMR$ spectroscopy using $D_2O$ and DMSO approved that DexLG nanoparticles have core-shell structure, i.e. hydrophobic block PLGA consisted inner-core as a drug-incorporating domain and dextran consisted as a hydrated outershell. Drug release rate from DexLG nano-particles became faster in the presence of dextranase in spite of the release rate not being significantly changed at high graft ratio of PLGA. Core-shell type nanoparticles of DexLG copolymer can be used as a colonic drug carrier. In conclusion, size, morphology, and molecular structure of DexLG nanoparticles are available to consider as an oral drug targeting nanoparticles.

• Bulletin of the Korean Chemical Society
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• 제31권2호
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• pp.435-441
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• 2010

We report the preparation and characterization of a new and water soluble complex of palladium(II) with 1,10- phenanthroline and butyldithiocarbamate ligands. This compound has been studied through spectroscopic techniques, $^1H$ NMR, IR, electronic spectra and elemental analysis and conductivity measurements. The complex shows 50% cytotoxic concentration ($Ic_{50}$) value against chronic myelogenous leukemia cell line, K562, much lower than that of cisplatin. Thus the mode of binding of this complex to calf thymus DNA have been extensively investigated by isothermal titration UV-visible spectrophotometry, fluorescence, gel filteration and other methods. UV-visible studies show that the complex exhibits cooperative binding with DNA and remarkably denatures the DNA at extremely low concentration ($~13\;{\mu}M$). Fluorescence studies indicate that the complex intercalate into DNA. Gel filtration studies suggest that the binding of Pd(II) complex with DNA is strong enough that it does not readily break. In these interaction studies, several thermodynamic and binding parameters are also determined which may reflect the mechanism of action of this type of compound with DNA.

• 농업과학연구
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• 제45권3호
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• pp.447-454
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• 2018

Zearalenone (ZEN), a mycotoxin produced by Fusarium in food and feed, causes serious damage to the health of humans and livestock. Therefore, we compared the metabolomic profiles in the liver, serum, and urine of piglets fed a ZEN-contaminated diet using proton nuclear magnetic resonance ($^1H-NMR$) spectroscopy. The spectra from the three different samples, treated with ZEN concentrations of 0.8 mg/kg for 4 weeks, were aligned and identified using MATLAB. The aligned data were subjected to discriminating analysis using multivariate statistical analysis and a web server for metabolite set enrichment analysis. The ZEN-exposed groups were almost separated in the three different samples. Metabolic analysis showed that 28, 29, and 20 metabolites were profiled in the liver, serum, and urine, respectively. The discriminating analysis showed that the alanine, arginine, choline, and glucose concentrations were increased in the liver. Phenylalanine and tyrosine metabolites showed high concentrations in serum, whereas valine showed a low concentration. In addition, the formate levels were increased in the ZEN-treated urine. For the integrated analysis, glucose, lactate, taurine, glycine, alanine, glutamate, glutamine, and creatine from orthogonal partial least squares discriminant analysis (OPLS-DA) were potential compounds for the discriminating analysis. In conclusion, our findings suggest that potential biomarker compounds can provide a better understanding on how ZEN contaminated feed in swine affects the liver, serum, and urine.

• 한국식품영양학회지
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• 제18권4호
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• pp.367-372
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• 2005

밤나무 잎에 함유된 기능성 물질 검색의 일환으로 항미생물 효과를 검정하고 활성물질의 분석을 시도하였다. 예비실험을 통해 추출물의 활성을 확인한 후 시료를 n-hexane, EtOAc, MeOH로 순차 추출하여 정제한 다음 활성이 강한 MeOH 분획의 0.2 g, 0.5 g에 해당하는 추출물로 13종의 미생물에 대해 활성을 측정한 결과, Cram 양성 세균 중에서 S. aureus와 S. epidermidis는 대조구로 사용한 benzoic acid보다 강한 활성이 나타났고, M. luteus와 L. mesenteroides, B. subtilis에서도 활성이 인정되었으며, Gram 음성 세균인 E. coli, S. typhimurium, P. aeruginosa에서도 강한 활성이 나타나 밤나무 잎 추출물은 비교적 넓은 항균 spectra와 활성이 있음이 확인되었다. 이에 활성물질을 규명하고자 시료를 solvent fractionation, silica gel adsorption column chromatography, Sephadex LH-20 column chromatography, HPLC 등으로 정제하고 활성이 나타난 산성 획분과 페놀성 획분의 물질을 분리한 후 MS, $^1H-NMR,\;^{13}C-NMR$ 등으로 분석한 결과, 산성 획분에서는 stigmast- 5-en-3-ol($\beta$-sitosterol)이 활성을 갖는 물질로 나타났다.

• 대한화학회지
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• 제35권4호
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• pp.368-373
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• 1991

isonitrosoethylacetoacetate(H-IEAA)의 이민유도체를 리간드로 하는 새로운 Pd(II) 착물, Pd(IEAA-NR)$_2$(R = H, CH$_3$, C$_2$H$_5$, n-C$_3$H$_7$, n-C$_4$H$_9$ 또는 CH$_2$C$_6$H$_5$)를 합성하고, 이들의 구조를 원소분석, 전자 흡수분광법, 적외선흡수분광법, $^1$H 및 $^{13}$C 핵자기공명 분광법으로 조사하였다. 그 결과 이들 Pd(Ⅱ) 착물은 모두 사각평면구조를 가지며, 착물에서 두 IEAA-NR 리간드가 모두 이민 질소와 N-O의 질소를 통하여 금속에 배위되어 5원 고리를 이루고 있음을 알 수 있었다.

• 분석과학
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• 제5권1호
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• pp.41-49
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• 1992

질소와 산소를 주게원자로 가진 5,7-dichloro-8-quinolinol(Hdcq)와 8-배위하는 텅그스텐(IV)과 세륨(IV) 착물과 질소와 황을 주게원자로 가진 2-mercaptopyrimidine[Hmpd] 리간드와 8-배위 텅스텐(IV) 착물을 합성하였으며 두자리 리간드 5,7-dichloro-8-quinolinol(Hdcq)과 2-mercaptopyrimidine(Hmpd)을 포함하고 있는 새로운 계열의 혼합 리간드 8-배위 텅그스텐(IV) 착물들을 합성하여 TLC법으로 분리하였다. 각각의 화학종 $W(dcq)_4$, $W(dcq)_3(mpd)_1$, $W(dcq)_2(mpd)_2$, $W(dcq)_3$와 $W(mpd)_4$의 MLCT 최대 흡수파장은 700nm, 680nm, 625nm, 581, 그리고 571nm(${\varepsilon}\;max={\sim}>{\times}10^4$)로 낮은 에너지에서 나타나며 $Ce(dcq)_4$의 특성파장은 520nm(${\varepsilon}\;max={\sim}>{\times}10^4$)에서 나타났다. $^1H$-NMR로 배위된 위치의 proton의 화학적 이동값이 $W(dcq)_4$ [$H_2:8.88ppm$]; $W(dcq)_3(mpd)_1$ [$H_2:9.30$, $H_6:9.18ppm$]; $W(dcq)_2(mpd)_2$ [$H_2:9.72$, $H_6:8.95ppm$]; $W(dcq)_1(mpd)_3$ [$H_2:9.77$, $H_6:9.39ppm$]; $W(mpd)_4$ [$H_6:8.80ppm$]; $Ce(dcq)_4$ [$H_2:9.30ppm$]이었다. 이 착물들에 대한 광활성 착물로써의 특성을 알아보기 위하여 극성용매인 DMSO $90^{\circ}C$에서 반응속도론적 안정성을 UV-Vis. 분광법으로 조사하여 안정도의 순위는 $W(dcq)_3(mpd)_1;k_{obs.}=3.8{\times}10^{-6}$ > $W(mpd)_4;k_{obs.}=6.0{\times}10^{-6}$ > $W(dcq)_4;k_{obs.}=6.4{\times}10^{-6}$ > $W(dcq)_2(mpd)_2;k_{obs.}=7.0{\times}10^{-6}$ > $W(dcq)_1(mpd)_3;k_{obs.}=1.7{\times}10^{-5}$로 각기 16일, 10일, 9일, 8일, 그리고 4일까지 안정하였으며 구조적 특성으로 고찰하였다. Xylene과 DMSO $90^{\circ}C$에서 $W(mpd)_4$는 Xylene에서 $k_{obs.}=3.6{\times}10^{-6}$(16일), DMSO에서 $k_{obs.}=6.0{\times}10^{-6}$(10일)로 매우 안정하였다.