• Journal of the Korean Magnetic Resonance Society
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• v.13 no.1
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• pp.15-26
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• 2009

The NMR detection of methyl groups is of keen interest because they provide the long-range distance information required to establish global folds of high molecular weight proteins. Using longitudinal $^1H$ relaxation optimization, we achieve a gain in sensitivity of approximately 1.6-fold in the methyl-TROSY and its NOESY experiments for the 38 kDa protein mitogen activated protein kinase p38 in its fully protonated and $^{13}C$ and $^{15}N$ labeled state.

• Archives of Pharmacal Research
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• v.19 no.4
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• pp.302-306
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• 1996

The $^1H- and^{13}C-NMR$ spectra of alaternin, aurantio-obtusin, chryso-obtusin, obtusin and 2-glucosyl obtusifolin isolated from the seeds of Cassia tora have been assigned based on HMBC, long-range HETCOR, fully $^1H-coupled {13}^C-NMR$, deuterium isotope experiment, and by comparison with the model compounds.

• Korean Journal of Crystallography
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• v.13 no.2
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• pp.82-85
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• 2002

From the reaction of cis,cis,trans- [MoBr/sub 2/(CO)/sub 2/(PPh/sub 3/)/sub 2/］with 2,6-dimethylphenyl isocyanide, a molybdenum oxohaloisocyanide compound cis,fac-[Mo(O)Br/sub 2/,(CN-C/sub 6/H/sub 3/,-2,6-Me/sub 2/)sub 3/] (1) was iso-lated. Compound 1 was characterized by spectroscopy (/sup 1/H-NMR, /sup 13/C｛/sup 1/H｝-NMR, IR) and X-ray diffraction. Crystallographic data for 1: triclinic space group 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).

• Journal of the Korean Chemical Society
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• v.38 no.10
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• pp.749-752
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• 1994

Two furanosesquiterpenes, (5'E)-5-(2',6'-dimethylocta-5',7'-dienyl) furan-3-carboxylic acid (1) and (1'E,5'E)-5-(2',6'-dimethylocta-l',5',7'-trienyl) furan-3-carboxylic acid (2), were isolated from soft coral Sinularia lochmodes collected from Palikir pass at Pohnpei Micronesia, June, 1990 in Hawaii. Their structures were elucidated by $^1H$, $^{13}C$ NMR, Homo-COSY, $^1H$-$^{13}C$ (1 bond) Heteronuclear Multiple Quantum Coherence Spectroscopy (HMQC), $^1H$-$^{13}C$ (2 and 3 bond) Heteronuclear Multiple Bond Coherence Spectroscopy (HMBC), Electron Impact Mass Spectroscopy (EI-ms), and Infrared Spectroscopy (IR).

• Korean Journal of Crystallography
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• v.12 no.1
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• pp.10-13
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• 2001

Compound PdCl₂(PhCN)₂(1) reacted with tert-butylamine(t-BuNH₂) to give trans-[PdCl₂(t-BuNH₂)₂] (2) Compound 2 was characterized by spectroscopy (¹H-NMR, /sup 13/C{¹H}-NMR, and IR) and X-ray diffraction. Crystallographic data for f2: monoclinic space group p2₁/c, a=6.298(1)Å, b=20.740(2)Å, c=10.731(1)Å, β=92.58(1)°, Z=4, R(wR₂)=0.0207(0.0543).

• The Korean Journal of Food And Nutrition
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• v.27 no.3
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• pp.532-537
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• 2014

Cortex Phellodendri (CP) is derived from the dried bark of Phellodendron amurense. It has been widely used as a drug in traditional Korea medicine for treating diarrhea, jaundice, swelling pains in the knees and feet, urinary tract infections, and infections of the body surface. Many analytical methods have been used to study oriental herbal medicines, such as thin-layer chromatography, column liquid chromatography, and high performance liquid chromatography (HPLC). In this study, preparative centrifugal partition chromatography (CPC) was successfully carried out in order to separate pure compounds from a CP methanol extract. The optimum two-phase CPC solvent system was composed of n-butanol: acetic acid: water (4:1:5 v/v/v). The flow rate of the mobile phase was 3 mL/min in ascending mode with rotation at 1,000 rpm. The CPC-separated fraction and purification procedures were carried out by preparatory HPLC. The $^1H$ NMR spectrum revealed that the resonances at ${\delta}$ 4.10 and 4.20 ppm corresponded to three protons ($-OCH_3$), whereas those at ${\delta}$ 6.10 ppm corresponded to two protons ($-OCH_2O-$). Further, two aromatic protons (H-11 and H-12) conveys a doublet-doublet pattern. The H-11 doublet and H-12 doublet appear at ${\delta}$ 7.98 and 8.11, respectively. The $^{13}C$ NMR. spectrum showed a tetrasubstituted with a methylenedioxy group at C2 and C3, and two methoxy groups at C9 and C10. The chemical structure of the berberine was identified by $^1H$, $^{13}C$-nuclear magnetic resonance and electrospray ionization-mass spectroscopy spectral data analysis.

• Natural Product Sciences
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• v.4 no.3
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• pp.153-157
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• 1998

The aqueous ethanolic leaf extract of Ailanthus altissima was found to contain the new natural product, $luteolin\;7-O-{\beta}-(6"-galloylglucopyranoside)$, 13, along with fourteen known phenolic metabolites (1-12, 14 and 15). Structures of all compounds (1-15) were established by conventional methods of analysis and confirmed by FAB-MS, $^1H-\;and\;^{13}C-NMR$ spectral analysis.

• Natural Product Sciences
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• v.26 no.2
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• pp.171-175
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• 2020

Liriodendron tulipifera, belonging to the family Magnoliaceae, is commonly called tulip tree. Four N-acetylated aporphine alkaloids, N-acetylnornuciferine (1), N-acetylanonaine (2), N-acetyl-3-methoxynornuciferine (3), and N-acetyl-3-methoxynornantenine (4) were isolated from the roots of L. tulipifera. Although the purity of each compound (1 - 4) was determined to be 97, 96, 99, and 98%, respectively, the ¹H and ¹³C NMR spectroscopic data of the aporphine alkaloids 1 - 4 displayed all signals in duplicate, indicating the presence of two rotamers due to restricted rotation of N-COCH₃ functionality in solution status. The absolute configurations of 1 - 4 w ere established by measuring specific rotation and comparison with the reported data. This is the first report on the ¹H and ¹³C NMR assignments of N-acetyl-3-methoxynornuciferine (3) and N-acetyl-3-methoxynornantenine (4). This study provides advanced NMR spectroscopic data for the structure determination of rotameric aporphine alkaloids.

• 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.

• BMB Reports
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• v.36 no.5
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• pp.505-507
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• 2003

One of the small proteins from Helicobacter pylori, acyl carrier protein (ACP), was investigated by NMR. ACP is related to various cellular processes, especially with the biosynthesis of fatty acid. The basic NMR resonance assignment is a prerequisite for the validation of a heterologuous protein interaction with ACP in H.pylori. Here, the results of the backbone $^1H$, $^{15}N$, and $^{l3}C$ resonance assignments of the H. pylori ACP are reported using double- and triple-resonance techniques. About 97% of all of the $^1HN$, $^{15}N$, $^{13}CO$, $^{13}C{\alpha}$, and $^{13}C{\beta}$ resonances that cover 76 of the 78 non-proline residues are clarified through sequential- and specific-assignments. In addition, four helical regions were clearly identified on the basis of the resonance assignments.