• Bulletin of the Korean Chemical Society
• /
• 제16권9호
• /
• pp.864-869
• /
• 1995

Investigation of the structures of the gangliosides has proven to be very important in the understanding of their biological roles such as regulation of differentiation and growth of cells. We used nuclear magnetic resonance spectros-copy in order to investigate the structure of GA1. In order to do this, the assignment of spectra is a prerequisite. Since GA1 does not have polar sialic acid, the spectral overlap is severe. In order to solve this problem, we use 2D NMR spectroscopy and heteronuclear 1H/13C correlated spectroscopy in this study. Here, we report the complete assignment of the proton and the carbon spectra of the GA1 in DMSO-d6-D20 (98:2, v/v). These assignments will be useful for interpreting 1H and 13C NMR data from uncharacterized oligosaccharides and for determining the linkage position, the number of sugar rings, and the sequence of new ganglioside. Amide proton in ring Ⅲ shows many interring nOes and has intramolecular hydrogen bonding. This appears to be an important factor in tertiary folding of GA1. Based on this assignment, determination of three dimensional structure of GA1 will be carried out. Studies on the conformational properties of GA1 may lead to a better understanding of the molecular basis of its functions.

• Journal of the Korean Wood Science and Technology
• /
• 제35권6호
• /
• pp.145-151
• /
• 2007

산겨릅나무 수피의 성분 연구를 위해 수피를 채취하여 70% 아세톤 용액으로 추출하고 농축한 후 분획깔때기로 헥산, 디클로로메탄, 에틸아세테이트 및 수용성으로 순차 추출하여 동결건조하였다. 에틸아세테이트용성 분획에 대하여 Sephadex LH-20 칼럼크로마토그래피를 반복적으로 수행하여 5개의 페놀성 화합물을 분리하였다. 화합물의 구조는 $^1H-NMR$, $^{13}C-NMR$, 2D-NMR 및 MS 스펙트럼을 분석하여, (+)-catechin (1), (-)-epicatechin (2), (-)-epicatechin-3-O-gallate (3), gallic acid (4) 및 6''-O-galloylsalidroside (5)으로 동정하였다. (-)-epicatechin-3-O-gallate (3), gallic acid (4), 6''-O-galloylsalidroside (5)는 산겨릅나무 수피에서 처음 분리되었다.

• 미생물학회지
• /
• 제54권2호
• /
• pp.136-139
• /
• 2018

풋마름병 균에 대해 강한 저해활성을 갖는 활성물질 Compound S와 conversion product인 compound S'이 Bacillus subtilis JW-1 배양액에서 일련의 크로마토그래피 방법으로 분리 정제되었고, $^1H$ NMR, $^{13}C$ NMR, $^1H-^1H$ COSY와 HMBC 등의 spectra 분석에 의해 구조가 alanyl-L-${\beta}$-(2,3-epoxycyclohexyl-4-one)alanine와 alanyl-L-${\beta}$-(2,3-dihydroxycyclohexyl-4-one) alanine로 각각 동정되었다. Compound S는 $G^+$, $G^-$ bacteria, yeast와 Candida albicans 등에 대해 광범위한 antimicrobial activity를 나타내며, conversion product의 활성 상실을 통해 intact oxirane ring이 Compound S의 활성에 필수적임이 밝혀졌다.

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

• 한국결정학회지
• /
• 제13권2호
• /
• pp.82-85
• /
• 2002

cis,cis,trans-[MoBr/sub 2/(CO)/sub 2/(PPh/sub 3/)/sub 2/］와 2,6-dimethylphenyl isocyanide의 반응으로부터 화합물cis,fac-[Mo(O)Br/sub 2/,(CN-C/sub 6/H/sub 3/,-2,6-Me/sub 2/)sub 3/] (1)이 분리되었다. 화합물 1의 구조가 분광학적 방법(/sup 1/H-NMR, /sup 13/C｛/sup 1/H｝-NMR, IR) 및 X-ray 회절법으로 규명되었다. 화합물 1의 결정학 자료: 삼사정계 공 간군 P(equation omitted), a=9.172(2) (equation omitted), b ＝ 11.550(3) (equation omitted), c ＝ 15.106(3) (equation omitted), α ＝ 100.44(2)°, β＝ 107.12(2)°, γ＝ 107.83(1)°, Z ＝ 2, R(wR/sub 2/) ＝ 0.0529(0.1344).

• 멤브레인
• /
• 제13권2호
• /
• pp.110-117
• /
• 2003

술폰화 폴리이미드는 클로로알칼리 전기분해, 양이온교환수지 및 연료전지용 고분자진해질막 등과 같은 많은 응용에 있어 유용한 재료로서 연구되어지고 있다. 그러나, 이러한 응용이 이루어지는 과정에 있어서 시간에 따라 연속적인 탈수공정이나 고분자의 분해에 따른 성능 감소 등이 보고되었다. 술폰화 고분자 분해의 주요 원인 중 하나로서 고분자 분자량의 감소 및 고분자 사슬의 절단으로 이끌어지는 가수분해를 들 수 있다. 따라서, 본 연구의 목적은 수화조건 하에서의 $-SO_3$H와 연결된 이미드 사이클과 부가적인 에스테르 결합의 분해를 조사하는 데 있다. 사슬의 분리에 대해 가능한 정확한 정보를 얻고 이를 확인하기 위해서는 $^1H$ 및 $^{13}C$ NMR, FT-IR 분석을 이용했으며, 또한 보다 편리한 분석을 위해서 model compound를 사용하여 실험을 수행하였다. 결과적으로, 술폰화 폴리이미드의 수화안정성을 평가하기 위해서 프탈계 및 나프탈렌계 이미드 고리와 에스테르 결합을 갖는 model compound를 합성하였고, 제조된 model compound를 이용하여 $80^{\circ}C$ 초순수 하에서 aging 실험을 수행하였고, lyophilization technique을 사용하여 반응을 중지시켰다. Aging된 product는 NMR, FT-IR spectroscopy를 이용하여 분석하였다.

• Mycobiology
• /
• 제50권2호
• /
• pp.110-120
• /
• 2022

The goal of the present study was to investigate the antibacterial properties, enzyme production, and metabolic profiling of a new Ceratorhiza hydrophila strain isolated from the submerged aquatic plant Myriophyllum spicatum. Furthermore, the fungus' morphological characterization and DNA sequencing have been described. The fungus has been identified and submitted to the GenBank as Ceratorhiza hydrophila isolate EG19 and the fungus ID is MK387081. The enzyme analyses showed its ability to produce protease and cellulase enzymes. According to the CSLI standard, the ethyl acetate extract of C. hydrophila showed intermediate antibacterial activity against Streptococcus pneumonia, Micrococcus luteus, and Staphylococcus aureus. Metabolic profiling has been carried out using 700 MHz NMR spectroscopy. Based on the ¹H and ¹H-¹³C heteronuclear single quantum coherence (HSQC) NMR data and NMR databases, 23 compounds have been identified. The identified metabolites include 31% amino acids, 9% sugars, 9% amines, 4% sugar alcohols, and 4% alkaloids. This is the first report for the metabolic characterization of C. hydrophila, which gave preliminary information about the fungus. It is expected that our findings not only will pave the way to other perspectives in enormous applications using C. hydrophila as a new promising source of antimicrobial agents and essential metabolites, but also it will be valuable in the classification and chemotaxonomy of the species.

• BMB Reports
• /
• 제29권5호
• /
• pp.423-428
• /
• 1996

A superoxide anion radical scavenger isolated from Capsella bursa-pastoris was characterized by infrared (IR) spectroscopy, sugar analysis, ultraviolet (UV) spectroscopy, $^{1}H$ and $^{13}C$ nuclear magnetic resonance (NMR) spectroscopies, and fast atom bombardment (FAB) mass analysis. The compound was assumed to be a flavonoid-O-glycoside from IR spectrum and UV absorption maxima. When the sugar composition of the compound was examined by thin layer chromatography (TLC) and gas chromatography (GC) of the acid hydrolysate, only glucose was detected. According to the results of UV spectrotroscopy by using shift reagents, the compound was supposed to be luteolin (5,7,3',4'-tetrahydroxy flavone) or chrysoeriol (5,7,4'-trihydroxy-3'-methoxy flavone) with glucose. Based on $^{1}H$- and $^{13}C-NMR$ spectroscopies, the compound was deduced as 7,4'-dihydroxy-5,3'-dimethoxy-${\alpha}$-6-c-glucosyl-${\beta}$-2"-o-glucosyl flavone. In FAB mass analysis the compound was finally characterized as 7,4'-dihydroxy-5,3'-dimethoxy-${\alpha}$-6-c-glucosyl-${\beta}$-2"-o-glucosyl flavone ($C_{29}H_{34}O_{16}$, M.W.=638).

• 한국자원식물학회지
• /
• 제19권6호
• /
• pp.655-659
• /
• 2006

Two dineolignans (1,2) with nitric oxide inhibitory activities were isolated from Saururus chinensis (Saururaceae) using silica gel column chromatography. Although the structures, saucernetin-7 (1) and -8 (2), have been already reported, NMR assignment of the two compounds was completed aided by 2D-NMR spectroscopy including $^1H-^1H$ COSY, $^1H-^{13}C$ COSY, HMBC and NOESY NMR spectra. Compounds 1 and 2 exhibited significant nitride oxide inhibitory activity in LPS-induced RAW 264.7 cells with $IC_{50}$ values of $11.3{\mu}M\;and\;7.1{\mu}M$, respectively.

• Bulletin of the Korean Chemical Society
• /
• 제31권8호
• /
• pp.2255-2260
• /
• 2010

In this study, some novel thiosubstituted butenyne (3a-d, 7b, 15b), butadiene (4a-b, 4d, 5a, 5c, 6b, 8e, 9c, 10b, 16b, 18e) and [3]cumulene (11a-b with isomer 3a-b, 12a with isomer 13a, 14b, 17e) compounds were synthesized from the reaction of 2H-pentachloro-1,3-butadiene with thiols. The new compounds were characterized by elemental analysis, mass spectrometry, UV-vis, IR, 1H NMR, NMR ($^{13}C$ or APT) spectroscopy.