• Korean Journal of Pharmacognosy
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• v.38 no.4
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• pp.354-357
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• 2007

Three compounds (1-3) were isolated from the roots of Potentilla discolor (Rosaceae). The structure of compounds 1-3 were elucidated as stigmast-5-en-3-ol $({\beta}-sitosterol,\;1),\;2,19{\alpha}-dihydroxy$-2-oxo-urs-1,12-dien-28-oic acid (fupenjic acid, 2), 3-O-${\beta}$-D-glucopyranosylstigmast-5-en-3-ol (${\beta}-sitosterol\;{\beta}-D-glucopyranoside, 3) based on physical and spectroscopic data. $^{13}C-NMR$ assignments were completed by 2D-NMR technique. The three compounds were firstly isolated from Potentilla discolor.

• Bulletin of the Korean Chemical Society
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• v.34 no.3
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• pp.936-942
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• 2013

Series of (E)-1-aryl-3-(2-pyrrolyl)-2-propenones, that were aldol condensation products between pyrrole-2-carbaldehyde and m- and p-substituted acetophenones, were prepared and their $^1H$ and $^{13}C$ NMR spectra were examined to obtain the information on the conformation of the enone system. Similar studies were carried out with (E)-3-aryl-1-(2-pyrrolyl)-2-propenones that were prepared from 2-acetylpyrrole and m- and p-substituted benzaldehydes. The substituent chemical shifts were studied by applying the Hammett relationship.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.573-576
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• 2007

가스 하이드레이트의 구조-I 및 구조-H의 공존 현상을 13C NMR과 Raman spectroscopy를 이용하여 분석하였다. 하이드레이트 생성 조건이 구조-H 영역에만 있을 때는 CH4+neohexane 혼합 하이드레이트가 구조-H만을 나타냈지만, 구조-I의 영역에서는 구조-H의 혼합 하이드레이트와 구조-I의 순수 메탄 하이드레이트가 공존하는 것을 $^{13}C$ NMR spectra를 통해 확인하였다. 이러한 현상은 구조-H 생성자로 알려진 isopentane, MCP, MCH 에서도 관찰되었으며, Raman spectroscopy를 이용해서도 확인할 수 있었다.

• Journal of the Korean Magnetic Resonance Society
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• v.4 no.2
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• pp.125-132
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• 2000

The detailed $^1$H and $^{13}$ C NMR assignments of a novel sucrose isovaleryl ester isolated from the seed of Euphorbia Lathyris L., were achieved by one-and two-dimensional techniques. The new sucrose ester was characterized as an $\alpha$-D-glucopyranoside, 3,4,6-tris-O-(3-methyl-1-oxobutyl)-$\beta$-D-fructofuranosyl, 2,6-bis(3-methylbutanoate); sucrose 4,7,8,11,12-pentaisovalerate by MS and NMR experiments.

• Archives of Pharmacal Research
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• v.18 no.5
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• pp.361-363
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• 1995

Two furofuran lignans, sesamolin and sesangolin were isolated from the seeds of Sesamum indicum and S.angolense, respectively. Detailed analysis of the $^1H-and^{13}C-NMR$ spectra of these lignans was carried out by the application of two-dimensional $^1H-^1/H\; COSY\; and^1/H^{13}C$ multiple-bond, multiple-quantum spectroscopic correlation techniques.

• YAKHAK HOEJI
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• v.39 no.1
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• pp.85-93
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• 1995

Acidic and alkaline hydrolysis of diol-type ginseng saponins produced a new glycoside, (20E)-ginsenoside Rh$_{3}$, and its stereoisomer (20Z)-, which were further subjected to alkaline by drolysis to give their aglycones, (20E)- and (20Z)-3$\beta$, 12$\beta$-dihydroxy-dammar-20(22),24-diene. The ratio of stereoisomeric mixtures was estimated to be ca. 5:1 from intensities of the peaks in $^{1}$H- and $^{13}$C-NMR spectra. The $^{1}$H- and $^{13}$C-NMR signals of ginsenoside Rh$_{3}$, which have remained unclarified, were completely assigned by the extensive application of modern NMR techniques.

• Journal of Integrative Natural Science
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• v.6 no.2
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• pp.65-70
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• 2013

1,1-Bis(n-butyl)-2,3,4,5-tetraphenyl-1-silacyclopentadiene (3) and 1,1-bis(t-butyl)-2,3,4,5-tetraphenyl-1-silacyclopentadiene (4) are synthesized from the reaction of the versatile silole dianion (2) with n-butyl bromide and t-butyl bromide. Reduction of (3) and (4) with an excess of lithium to give 1,1-bis(n-butyl)-2,5-dilithio-2,3,4,5-tetraphenyl-1-silacyclopenta-3-enide (6) and 1,1-bis(t-butyl)-2,5-dilithio-2,3,4,5-tetraphenyl-1-silacyclopenta-3-enide (7). $^{13}C$-NMR study of two 2,5-carbodianions (6 and 7) shows tert-carbanion at 73.18 and 78.12 ppm respectively. Two bulky tert-butyl groups in (7) increase the inversion barrier at the tert-carbanion, line broadenings of tert-butyl groups in $^1H$ and $^{13}C$-NMR spectrum are observed.

• Korean Journal of Microbiology
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• v.23 no.4
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• pp.241-247
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• 1985

The objectives of this study were to isolate and identify ninhydrin positive substande(s) produced in the culture broth of Pseudomonas fluorescens. It was found that the NPS could stimulate bioconversion of furfural into furoic acid. In order to isolate the NPS from the culture broth, cell free filtrate was subjected to ion-exchange chromatography, gel-permeation and finally to cellulose column chromatography. The purified NPS was white amorphous power and very soluble in water, slightly soluble in methanol and very insoluble in organic solvents. UV, and IR absorption spectra. $^H$ and $^{13}C-NMR$ were measured in order to identify the chemical structure of the NPS.

• Bulletin of the Korean Chemical Society
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• v.19 no.8
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• pp.847-851
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• 1998

13C, 15N, and 29Si NMR chemical shifts have been computed for selected X-substituted silatranes (X=Cl, F, H, CH3) using Gauge-Including Atomic Orbitals (GIAO) and Continuous Set of Gauge Transformations (CSGT) at the Hartree-Fock level of theory. The isotropic 13C chemical shifts are largely insensitive to substituent-induced structural changes. In this study, the isotropic 13C chemical shifts GIAO and CSGT calculations at the HF/6-31G and HF/6-31G* levels are sufficiently accurate to aid in experimental peak assignments. The isotropic 13C chemical shifts X-substituted silatranes at HF/6-31G* level are approximately 4 ppm different from the experimental values. In contrast, the isotropic 15N and 29Si chemical shifts and the chemical shielding tensors are quite sensitive to substituent-induced structural changes. These trends are consistent with those of the experiment. The 15N chemical shift parameters demonstrate a very clear correlation with Si-N distance, especially when we use the polarization function. Changes in anisotropy, 3a as well as in the 15N isotropic chemical shifts are due primarily to changes in the value of a.. But in case of "Si the correlations are not as clean as for the 15N chemical shift.

• Advances in Traditional Medicine
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• v.9 no.4
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• pp.315-319
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• 2009

In present study evaluate the analgesic and anti-inflammatory activity of the compound obtained from the petroleum ether (40 - 60$^{\circ}C$) extract of the fruits from Dregea volubilis in Swiss albino mice and in Wister albino rats respectively. Dried and crushed fruits of Dregea volubilis were extracted by petroleum ether (40 - 60$^{\circ}C$), the proper solvent system was developed by TLC and subjected to column chromatography for obtaining the pure compound/s. IR, MASS, NMR (PMR, C13 NMR and DEPT) spectroscopic analysis were done to elucidate the structure of the compound/s. The petroleum ether (40 - 60$^{\circ}C$) extract of the fruits of Dregea volubilis led to isolation of a pentacyclic triterpenoid designated as taraxerone and characterized as D- friedoolean- 14- en, 3 one. Taraxerone had been screened for analgesic activity in Swiss albino mice and anti-inflammatory activity in Wister albino rats at the dose of 5 mg/kg body weight orally and exhibit significant analgesic and anti-inflammatory properties.