• Bulletin of the Korean Chemical Society
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• 제25권5호
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• pp.609-616
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• 2004

Complexation of cesium ion by p-tert-butylcalix[6]arene ethyl ester was studied by NMR spectroscopy in nonpolar $CDCl_3$ and polar acetone-$d_6$ and the results were compared with each other. Analysis of temperature dependent $^1H$ spectra and titration curves reveals that both solvents result in a 1 : 1 cone-form complex with nonpolar $CDCl_3$yielding a more tightly bound one than acetone-$d_6$. Unexpectedly, at very low temperature, we have found that two phenyl ring proton peaks of equal intensity appear both in $CDCl_3$and in acetone-$d_6$ solution which gradually collapse and eventually coalesce into a single line as temperature is raised. This observation could be interpreted in terms of the chemical exchange through direct and/or indirect interconversion between two equivalent conformations possible the complex in both solvents over the temperature range observed. And broadening of $^{133}Cs$ (I = 7/2) nmr line with increasing temperature has also been observed, indicating the exchange of $^{133}Cs$ ion between the complex and the solvent. From numerical fitting of lineshape changes for one-dimensional $^1H$ and $^{133}Cs$ spectra, the exchange rate constants and other relevant parameters for this conformational interconversion and the complex-solvent exchange were deduced.

• Applied Biological Chemistry
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• 제41권2호
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• pp.191-196
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• 1998

할미꽃 $(Pulsatilla\;koreana\;N_{AKAI})$ 뿌리인 백두옹의 MeOH 추출물이 세균과 효모 등의 미생물에 대해 항미생물 활성을 나타내자 백두옹에 함유된 항미생물 활성물질의 탐색을 시도하였다. MeOH 추출물을 생물검정법을 지표로 solvent fractionation, silica gel adsorption column chromatography, Sephadex LH-20 column chromatography 등으로 정제하고, HPLC에 의해 활성물질을 분리하였다. 분리된 두 활성물질은 MS, $^{1}H-NMR$, $^{13}C-NMR$에 의해 4-hydroxy-3-methoxycinnamic acid와 3,4-dihydroxycinnamic acid로 동정되었다.

• The Korean Journal of Ecology
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• 제21권1호
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• pp.35-45
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• 1998

This study was carried out for the identification and bioassay of bioactive compounds which isolated from Phyutolacca americana L. obtained results are summarized as follows: 1. Two biological active compounds were found from crude extracts of P. americana roots, using the systematic solvent fractionations, such as ethyl acetate fraction and butanol fraction. One biological compound was isolated from the ethyl acetate fraction with silicagel column chromatography, which was identified as a ${\alpha}-spinasterol$ by spectral analysis of IR, H-NMR, C-NMR and MS. The other one is isolated from butanol fraction which was identified as phytolaccoside E by spectral analysis of IR, H-NMR, C-NMR and MS. 2. The ${\alpha}-spinasterol$ and phytolaccoside E induced necrosis of primary root and resulted in death of the tested plant. These two compounds strongly inhibited to the growth of Mucor racemous and Phytophthora infestants but did not inhibited the growth of Colletotricum lagenarium and Fusarium oxisporum. 3. Cytotoxicity of the two biological active compound was exammined to the two different animal cancer cell lines (L1210, K562). The phytolaccoside E has some cytotoxical activity to the growth of cancer cell lines (L1210, K562) but $\alpha$-spinasterol has not cytotoxical effect.

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

• 한국결정학회지
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• 제10권1호
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• pp.45-50
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• 1999

Ar 기류하에서 trans-[FeH(NCCH2CH2CH2Cl)(dppe)2][BF4], 1과 KCN이 반응하여 trans-[FeH(CN)(dppe)2], 2가 생성되었다. 이 화합물의 구조가 NMR, IR, 원소분석, 그리고 X-ray 회절법으로 규명되었다. 착물 2의 결정학 자료: 단사정계 공간군 p21/c, a=13.580(1) b=20.178(2) , c=17.592(3) , β=92.22(1)o, Z=4,(wR2)=0.0659(0.1692).

• Bulletin of the Korean Chemical Society
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• 제19권5호
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• pp.501-503
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• 1998

In this work, we applied the 1D $11^B$ nutation NMR method for the analysis of the local structural environments in powdered borosilicates $(SiO_2-B_2O_3)$. Spin dynamics during a rf irradiation for spin I=3/2 was analytically calculated with a density ma trix formalism. Spectral simulation programs were written in MATLAB on a PC. Two borosilicates prepared by the sol-gel process at different stabilization temperature were used for the 1D $11^B$ nutation NMR experiment. The $11^B$ NMR parameters, quadrupole coupling constants $(e^2qQ/h)$ and asymmetry parameters (η), for each borosilicate were extracted from the nonlinear least-squares fitting. The effects of heat treatments on the local structures of boron sites in borosilicates were discussed.

• 대한화학회지
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• 제56권3호
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• pp.334-340
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• 2012

A new series of ethyl 2-(4-substitutedbenzylidene)-5-(3'-(ethoxycarbonyl)biphenyl-4-yl)-7-methyl-3-oxo-3,5-dihydro-2H-thiazolo[3,2-a]pyrimidine-6-carboxylate derivatives ($\mathbf{8a-j}$) were synthesized. The newly synthesized compounds were characterized by $\mathbf{IR}$, $^1\mathbf{H}$ $\mathbf{NMR}$, $^{13}\mathbf{C}$ $\mathbf{NMR}$, $\mathbf{LCMS}$ $\mathbf{mass}$ and $\mathbf{C}$, $\mathbf{H}$, $\mathbf{N}$ analyses. All newly synthesized compounds were screened for their In vitro antioxidant activity (Scavenging of hydrogen peroxide, Scavenging of nitric oxide radical, and Lipid peroxidation inhibitory activity), antibacterial (Escheria coli, Pseudonmonas aeruginosa (gram-negative bacteria), Bacillus subtillis, Staphylococcus aureus (gram-positive bacteria)) and antifungal (Candida albicans Aspergillus niger) studies.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.215-218
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• 2002

식물병원균에 대한 Helicosporium 의 항균작용을 확인하기 위하여 식물병원균인 Rhizoctonia solani, Rhizoctonia solani AG2-2, Fusarium oxysporium, Phytophthora dreschler, Alternaria 속을 선정하였고, 이에 대한 항균작용을 검토한 결과, Rhizoctonia solani, Rhizoctonia solani AG2-2 에는 강한 항균활성을 나타내었으며, Alternaria에는 미약한 항균활성을 가졌으며 Fusarium oxysporium, Phytophthora dreschler에 대해서는 항균활성을 하지 않는 것으로 확인되었다. 이 항균물질의 구조를 $^1H-NMR$ 스펙트럼을 통해서 분석한 결과 이 물질은 콜레스테롤 에 해당하는 구조를 가진 것으로 추정된다.

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

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.455-458
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• 2011

In previous report, with the aid of receptor-oriented pharmacophore-based in silico screening, we characterized three novel hPNMT inhibitors (YPN010, YPN016, and YPN017) and proposed that the hydrogen bonding interaction between inhibitors and side chain of Lys57 is very important to inhibitory activity of hPNMT. To confirm the importance of Lys57, mutant with substitution of Lys57 with Ala was cloned and binding study was performed for a K57A mutant of hPNMT using STD-NMR and fluorescence experiments. The binding constants for three novel inhibitors with mutant hPNMT were dramatically decreased compared to those with wild-type protein. K57A mutant-induced conversion of noradrenaline to adrenaline was suppressed about 95 % compared to wild-type hPNMT. Mutagenic analysis using a K57A mutant confirmed the importance of the Lys57 residue in binding of the inhibitor candidate to hPNMT as well as enzymatic activity of hPNMT, implying that these results are consistent with our binding model.