• 대한화학회지
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• 제38권3호
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• pp.194-199
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• 1994

Sodium dodecylsulfate(SDS) 0.2M수용액 미셀내에 몇 가지 페닐 알카놀$[C_6H_5(CH_2)_nOH;$ 페놀(n=1), 벤질 알코올(n=1), 펜에틸 알코올(n=2), 3-페닐-1-프로판올(n=3)]이 가용화(solubilization)될 때 이들의 가용화 위치를 이차원 이핵 상관 NMR분광법(Two dimensional heteronuclear correlation spectroscopy (2D C-H COSY)으로 조사하였다. 실험 결과 $^1H$-NMR 신호의 적분에 의하여 조사한 이전의 연구결과보다 훨씬 정량적이며 정확한 가용화 위치를 알 수 있었다. 이들이 SDS 미셀 중심의 중간부 메틸렌기에 침투하는 깊이는 ${\alpha}$메틸렌기로부터 6.5~7.0 단위까지 임을 알았다.

• Investigative Magnetic Resonance Imaging
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• 제12권2호
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• pp.107-114
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• 2008

목적 : 3T MR 기기를 이용하여, 췌장 주위에 발생한 낭성 종양에 대하여, 생체내, 그리고 생체외 생체내 자기공명분광법(magnetic resonance spectroscopy: MRS)를 획득한 후, 생체외 핵자기공명 (nuclear magnetic resonance, NMR) 스펙트럼을 기준으로 비교함으로써, 낭성 종양의 감별 진단에 있어 MRS의 적용 가능성을 알아보고자 하였다. 대상 및 방법 : 췌장 주위에 발행한 12예의 낭성 종양(점액성 낭성 종양=5, 췌담관내 유두종=5, 가성 낭종=1, 및 림프관종 n=1)을 대상으로 3.0T 생체내, 생체외 양성자 MRS 및 9T NMR 스펙트럼을 획득하였다. NMR의 피크와 상응하는 생체내, 생체외 양성자 MRS에서 관찰되는 피크의 존재유무를 알아보았으며, 특정 질환을 예측하는 피크에 대하여 알아보았다. 결과 : 생체내 MRS는 NMR과 민감도 29.6%, 특이도 82.6% 그리고, 67.7%의 정확도를 보였으며 (p=0.096, McNemar test), 생체외 MRS는 생체내 MRS는 민감도 57.1%, 특이도 92.6%, 그리고, 82.3%의 정확도를 보였다 (p = 0.362, McNemar test). 질병간의 스펙트럼의 차이는 NMR에서 췌담관내 유두종의 경우에서 점액성 낭성 종양에 비해 3.5-4.0 ppm에서 유의하게 많은 피크를 보였다 (p=0.026). 결론 : 결론적으로, NMR 이용한 화학물질 분석은 낭성 종양의 감별 진단에 도움이 될 가능성이 있는 기법으로 생각되지만, 생체내 및 생체외 MRS는 임상에 적용되기 위해서는 많은 기술적 발전을 필요로 하는 것으로 생각된다.

• 대한본초학회지
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• 제23권3호
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• pp.27-32
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• 2008

Objectives : In this paper, we describe that $^1H-NMR$ spectroscopy may be superior to the conventional HPLC for the quantitative analysis of hesperidin from Citrus unshiu. Methods : $^1H-NMR$ spectra (400 MHz) were recorded in $DMSO-d_6$ using a Varian UNITY Inova AS 400 FT NMR spectrometer. One hundred milligram of powdered Citrus unshiu was weighed out and mixed with 1 ml of $DMSO-d_6$ with sonication for 30 min (room temperature). The extracts were filtrated through a 0.45 ${\mu}m$ PVDF filter and 0.5 ml of filtrated extract used for quantitative $^1H-NMR$ measurement (added 1 mg of dimethyl terephthalate as internal standard). The quantity of hesperidin was calculated by the ratio of the intensity of the compound to the known amount of internal standard. For HPLC analysis, the half gram of plant material was extracted with 60 ml of MeOH for 2 hours. The extracts were made 100 ml volume and analyzed by a Waters HPLC system using a YMC ODS column. The total flow rate was 1.0 ml/min with a sample volume 10 ${\mu}l$ and UV detection at 280nm. Results : The contents of hesperidin in Citrus unshiu was determined $5.33{\pm}0.06$% in the quantitative $^1H-NMR$ method and $5.15{\pm}0.12%$ in HPLC method. Using the quantitative $^1H-NMR$ the contents of hesperidin can be determined in much shorter time than the conventional HPLC measurements. Conclusions : From those results, the advantages of quantitative $^1H-NMR$ analysis are that can be analyzed to identify and quantify, and no reference compounds required for calibration curve. Besides, it allows rapid and simple quantification for hesperidin with an analysis time for only 10 min without any pre-purification steps.

• Bulletin of the Korean Chemical Society
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• 제17권8호
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• pp.696-699
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• 1996

Silicate and borosilicate gels were prepared by the sol-gel process and thermally treated in the 150-850 ℃ temperature range. Solid-state 1H MAS and 29Si CP/MAS NMR spectroscopy were used to investigate the effects of heat treatments on the silicate gel to glass conversion process. The 1H NMR isotropic chemical shifts and the relative intensities of hydrogen bonded and isolated silanol groups have been used to access the information concerning the dehydration process on the silicate gel surface. The 29Si NMR isotropic chemical shifts affected by the local silicon environment have been used to determine the degree of crosslinking, i.e. the number of siloxane bonds. These NMR results suggest that the silicate gel to glass conversion process is occurred by two stages which are dependent on the temperature; (1) the formation of particles up to 450 ℃ and (2) the formation of large particles by aggregation of each separated single particle above 450 ℃. In addition, the effects of B atom on the formation of borosiloxane bonds in borosilicates have been discussed.

• 한국결정학회지
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• 제12권3호
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• pp.141-144
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• 2001

Na[Ga(N₃)₄]와 PPh₃의 반응으로부터 이온성 화합물 [Ph₃P(OH)]/sup +/[N₃]/sup -/ (1)이 분리되었다. 화합물1의 구조가 분광학적 방법(¹H-NMR, /sup 13/C{¹H-NMR, IR) 및 X-ray 회절법으로 규명되었다. 화합물1의 결정학 자료 : 사방정계 공간군 P2₁2₁2₁, a = 10.491(4)Å, b=11.603(5)Å, c=13.149(5)Å, Z=4, R(wR₂)=0.0547(0.0978).

• Macromolecular Research
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• 제13권4호
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• pp.334-338
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• 2005

A three-layered poly(benzyl ether) dendrimer having a bis-ethynylbenzene core was synthesized and characterized with $^{1}H$ NMR and MALDI-TOF-MS spectroscopy. The dendrimer was reacted with platinum complexes to obtain platinum-acetylide based organometallic polymers. When the dendrimer was reacted with trans-[$PtCl_{2}(PEt_{3})_{2}$], a high molecular weight polymeric compound was formed, whereas, with cis-[$PtCl_{2}dppp$], a uniform molecular weight compound was formed, which was found to be a dimeric metallacycle by $^{1}H\;NMR,\;^{31}P\;NMR$ and ESI-TOF-MS spectroscopy. Both these complexes exhibited relatively a strong emission around 440 nm, indicating that they could be potential candidates for blue emitting polymer LEDs.

• 한국자기공명학회논문지
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• 제25권1호
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• pp.8-11
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• 2021

Transthyretin (TTR) is an important transporter protein for thyroxine (T4) and a holo-retinol protein in human. In its native state, TTR forms a tetrameric complex to construct the hydrophobic binding pocket for T4. On the other hand, this protein is also infamous for its amyloidogenic propensity, which causes various human diseases, such as senile systemic amyloidosis and familial amyloid polyneuropathy/cardiomyopathy. In this work, to investigate various structural features of TTR with solution-state nuclear magnetic resonance (NMR) spectroscopy, we conducted backbone NMR signal assignments. Except the N-terminal two residues and prolines, backbone 1H-15N signals of all residues were successfully assigned with additional chemical shift information of 13CO, 13Cα, and 13Cβ for most residues. The chemical shift information reported here will become an important basis for subsequent structural and functional studies of TTR.

• 대한화학회지
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• 제63권2호
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• pp.78-84
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• 2019

High-resolution $^1H$ NMR spectroscopic technique has been widely used as one of the most powerful analytical tools in food chemistry as well as to define molecular structure. The $^1H$ NMR spectra-based metabolomics has focused on classification and chemometric analysis of complex mixtures. The principal component analysis (PCA), an unsupervised clustering method and used to reduce the dimensionality of multivariate data, facilitates direct peak quantitation and pattern recognition. Using a combination of these techniques, the various green teas and black teas brewed were investigated via metabolite profiling. These teas were characterized based on the leaf size and country of cultivation, respectively.

• Natural Product Sciences
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• 제4권4호
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• pp.221-225
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• 1998

A novel flavonol trisulphate, quercetin 7-methyl ether $3,3',4'-tri-O-KSO_3$ was isolated from the fresh leaves of Tamarix amplexicaulis (Tamaricaceae) along with the known flavonol mono sulphates, quercetin $3-O-KSO_3$ and quercetin 4'-methyl ether $3-O-KSO_3$. Structures were achieved through conventional analytical methods, including electrophoretic analysis and confirmed by FAB-MS and NMR spectroscopy.

• 한국응용과학기술학회지
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• 제37권5호
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• pp.1323-1329
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• 2020

대장균 효소 𝛽-gal를 이용하여 합성된 phenylethanol galactoside (PhE-gal)의 분자구조를 NMR (¹H-와 ¹³C-)과 고성능 mass spectrometry를 이용하여 분석하였다. 그 결과 PhE-gal은 ¹H NMR에서 2-phenylethanol (PhE)에 갈락토실기가 도입되었음을 나타내는 피크가 나타났다. 방향족 고리에서 오는 𝛿_H 7.30~7.21 ppm의 피크와 𝛿_H 2.88 ppm에 나타난 벤질기 위치의 CH₂에서 오는 피크는 PhE가 존재함을 나타낸다. 지방족 사슬 영역인 𝛿_H 4.31 ppm, 4.07 ppm과 𝛿_H 3.86~3.38 ppm에서 나타나는 7개의 proton 피크로부터 단당류가 도입되었음을 확인할 수 있었다. ¹³C NMR 스펙트럼에서 나타난 12개의 탄소 피크 중 4개의 피크는 방향족 고리인 페닐기로부터, 또한 단당류에서 기인한 6개의 탄소피크가 존재하므로 PhE에 단당이 도입되었음을 알 수 있다. PhE-gal의 분자량을 확인하기 위하여 질량분석기로 분석한 결과 m/z가 307.1181인 PhE-gal의 sodium adduct ion ([M+Na]⁺)이 나타나 생성물이 PhE-gal임을 알 수 있었다. 따라서 본 연구결과 E. coli 𝛽-galactosidase에 의한 촉매반응으로 PhE에 갈락토즈가 첨가된 생성물인 PhE-gal이 성공적으로 생합성 되었음을 확인하였다.