• Bulletin of the Korean Chemical Society
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• v.19 no.1
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• pp.63-67
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• 1998

The synthesis and characterization of the monomeric group 13 heterocyclic thiosemicarbazone complexes $Me_2M[SC_4H_3CHNNC(S)SCH_3]$ (M=Al (2), Ga (3)) are described. Compounds 2-3 were prepared using $MMe_3$ (M=Al, Ga) in toluene with 2-thiophenecarboxaldehyde-S-methyldithiocarbazat e under anaerobic conditions. These complexes have been characterized by $^1H\;NMR,\; ^{13}C\; NMR$, elemental analyses, and single-crystal X-ray diffraction. 2 crystallizes in the monoclinic space group $P2_1/c$ with unit cell parameters a=10.2930(5) Å, b=18.564 (1) Å, c=7.3812(6) Å, V=1347.9(2) Å3, $D_{calc}=1.342\; gcm^{-3}$ for Z=4, 9281 reflections with $I_o<3{\sigma}\;(I_o),$ R1=0.0500 and wR2=0.0526. 3 crystalizes in the orthorhombic space group $P_{bca}$ with unit cell parameters a=13.340(3) Å, b=19.9070(5) Å, c=11.3690(2) Å, $V=2673.88(9)\;{\AA}^3$, $D_{calc}=1.511\; gcm^{-3}$ for Z=8, 17004 reflections with $I_o>3{\sigma}\;(I_o),$, R1=0.0480 and wR2=0.0524. Compound 3 is a monomeric gallium compound with a weak interaction between the pendant thiophene and the gallium center.

• Archives of Pharmacal Research
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• v.28 no.9
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• pp.1031-1036
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• 2005

[ $(+)-Lyoniresinol-3{\alpha}-O-\beta-D-glucopyranoside$ ] (1) was isolated from an ethyl acetate extract of the root bark from Lycium chinense Miller, and its structure was determined using 1D and 2D NMR spectroscopy including DEPT, HMQC, and HMBC. $(+)-Lyoniresinol-3{\alpha}-O-\beta-D-glucopyranoside$ exhibited potent antimicrobial activity against antibiotic-resistant bacterial strains, methicillin-resistant Staphylococcus aureus (MRSA) isolated from patients, and human pathogenic fungi without having any hemolytic effect on human erythrocytes. In particular, compound 1 induced the accumulation of intracellular trehalose on C. albicans as stress response to the drug, and disrupted the dimorphic transition that forms pseudo-hyphae caused by the pathogenesis. This indicates that $(+)-Lyoniresinol-3{\alpha}-O-\beta-D-glucopyranoside$ has excellent potential as a lead compound for the development of antibiotic agents.

• Natural Product Sciences
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• v.12 no.2
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• pp.101-103
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• 2006

In the course of the continual work on the fresh tubers of Gastrodia elata, a fructoside constituent was isolated from the n-butanol soluble fraction prepared from the methanol extract. The structure of this compound was identified as $n-butyl-{\beta}-D-fructopyranoside$ from various spectroscopic data including $^1H-\;and\;^{13}C-NMR$, HMQC, HMBC, and FABMS.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.229-238
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• 2011

A series of novel glucose derived benzyl and alkyl 1,2,3-triazoles and their hydrochlorides have been synthesized via Cu(I)-catalyzed 1,3-dipolar cycloaddition. All the new compounds were characterized by MS, IR and NMR spectra. The DEPT, APT, $^1H$-$^1H$ and $^1H-^{13}C$ 2D NMR spectra for some compounds were also recorded. These compounds were evaluated for their in vitro antibacterial activities against Staphylococcus aureus ATCC 29213, Bacillus subtilis, Bacillus proteus, Pseudomonas aeruginosa, Escherichia coli ATCC 25922, and antifungal activities against Candida albicans and Aspergillus fumigatus. The bioactive data revealed that (3R,4S,5S,6S)-2-(hydroxymethyl)-6-methoxy-4,5-bis((1-octyl-1H-1,2,3-triazol-4-yl)methoxy)-tetrahydro-2H-pyran-3-ol 8a exhibited excellent antifungal activity against A. fumigatus with an MIC value of 0.055 mM compared to Fluconazole. It also showed broad inhibitory efficacy against tested bacterial strains with MIC values ranging from 0.049 mM to 0.39 mM.

• Natural Product Sciences
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• v.24 no.3
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• pp.213-218
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• 2018

Chemical investigation of the plant Tristemma hirtum P. Beauv (Melastomataceae) resulted to the isolation of a new flavonol glycoside named quercetin-7-O-${\alpha}$-D-arabinofuranoside (1), together with nine known compounds including 3'-hexadecanoyl-2'-(9aZ)-tetradecanoyl-glycerol 1'-O-[${\beta}$-D-galactopyranosyl-(1'' ${\rightarrow}$ 6'')-${\alpha}$-D-galactopyranoside] (2), arjunolic acid (3), ${\beta}$-sitosterol-3-O-${\beta}$-D-glucopyranoside (4), terminolic acid (5), quercetin (6), asiatic acid (7), maslinic acid (8), $1{\beta}$-O-galloylpedunculagin (9) and 6-hydroxyapigenin 7-O-${\beta}$-D-glucopyranoside (10) from the methanol extract using normal and reversed phase column chromatography. The structures of these compounds were determined by comprehensive interpretation of their spectral data mainly including 1D- 2D-NMR ($^1H-^1H$ COSY, HSQC, and HMBC) spectroscopic and ESI-TOF-MS mass spectrometric analysis.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3553-3560
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• 2010

A new hydrazone derivative compound has been synthesized and characterized by IR, $^1H$-NMR, $^{13}C$-NMR and UV-vis. spectroscopy techniques, elemental analysis and single-crystal X-ray diffraction (XRD). The new compound crystallizes in monoclinic space group C2/c. In addition to the crystal structure from X-ray experiment, the molecular geometry, vibrational frequencies and frontier molecular orbitals analysis of the title compound in the ground state have been calculated by using the HF/6-31G(d, p), B3LYP/6-311G(d, p) and B3LYP/6-31G(d, p) methods. The computed vibrational frequencies are used to determine the types of molecular motions associated with each of the observed experimental bands. To determine conformational flexibility, molecular energy profile of (1) was obtained by semi-empirical (AM1) calculation with respect to a selected degree of torsional freedom, which was varied from $-180^{\circ}$ to $+180^{\circ}$ in steps of $10^{\circ}$. Molecular electrostatic potential of the compound was also performed by the theoretical method.

• Natural Product Sciences
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• v.18 no.3
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• pp.200-203
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• 2012

The chromatographic separation of a methanol extract of Prunus mume (Rosaceae) led to the isolation of 5-hydroxymethyl-2-furaldehyde (1), 4-O-caffeoylquinic acid methyl ester (2), prunasin (3), 5-O-caffeoylquinic acid methyl ester (4), benzyl-O-${\beta}$-D-glucopyranoside (5), and liquiritigenin-7-O-${\beta}$-D-glucopyranoside (6). Their structures were determined by 1D, 2D-NMR and MS data analysis as well as by comparison of their data with the published values.

• Journal of the Korean Magnetic Resonance Society
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• v.24 no.4
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• pp.136-142
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• 2020

Apolipoprotein B-100 (apo B-100), the main protein component that makes up LDL (Low density lipoprotein), consists of 4,536 amino acids and serves to combine with the LDL receptor. The oxidized LDL peptides by malondialdehyde (MDA) or acetylation in vivo were act as immunoglobulin (Ig) antigens and peptide groups were classified into 7 peptide groups with subsequent 20 amino acids (P1-P302). The biomimetic peptide P99 (KGTYG LSCQR DPNTG RLNGE) out of B-group peptides carrying the highest value of IgM antigens were selected for structural studies that may provide antigen specificity. Circular Dichroism (CD) spectra were measured for peptide secondary structure in the range of 190-260 nm. Experimental results show that P99 has pseudo α-helice and random coil structure. Homonuclear (COSY, TOCSY, NOESY) 2D-NMR experiments were carried out for NMR signal assignments and structure determination for P99. On the basis of these completely assigned NMR spectra and proton distance information, distance geometry (DG) and molecular dynamic (MD) were carried out to determine the structures of P99. The proposed structure was selected by comparisons between experimental NOE spectra and back-calculated 2D NOE results from determined structure showing acceptable agreement. The total Root-Mean-Square-Deviation (RMSD) value of P99 obtained upon superposition of all atoms were in the set range. The solution state P99 has mixed structure of pseudo α-helix and β-turn(Gln[9] to Thr[13]). These NMR results are well consistent with secondary structure from experimental results of circular dichroism. Structural studies based on NMR may contribute to the prevent oxidation studies of atherosclerosis and observed conformational characteristics of apo B-100 in LDL using monoclonal antibodies.

• Bulletin of the Korean Chemical Society
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• v.27 no.7
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• pp.995-1000
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• 2006

Three new compounds orizaanthracenol (1-methoxyanthracen-2-ol, 1), 1-hydroxy-7-((2S,3R,4R,5S)-2'',3'',4''-trihydroxy-5''-(hydroxymethyl)tetrahydro-2H-pyran-1-yloxy)anthracen- 2-yl 3',7'-dimethyloctanoate (2) and 1-hydroxy-7-((2S,3R,4R,5S)-2'',3'',4''-trihydroxy-5''-(hydroxymethyl)tetrahydro-2H-pyran-1-yloxy)anthracen- 2-yl 3',7',11',15',19'-pentamethyltricosanoate (3) have been isolated and determined from the rice hulls of Oryza sativa. The structures of the compounds were elucidated using 1D and 2D NMR spectral methods, viz: 1H-NMR, 13C-NMR, DEPT, COSY and HSQC, and HMBC aided by IR, EIMS and FAB-MS. These isolated compounds were tested in bioassay on germination of radish to detect their inhibitory activities, in which compound 1 exhibited the most inhibition at the concentration of 40 ppm was 50.96% of total dry weight. Furthermore, germination and growth of radish were reduced by 27 to 48%, and dry weight of shoot and root were arranged from 50 to 52%, whilst compounds 2 and 3 exhibited weak inhibition than 1.

• Korean Journal of Pharmacognosy
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• v.44 no.1
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• pp.6-9
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• 2013

Two fraxinellone-based hydrogenated derivatives were prepared from fraxinellone, a well-known degraded limonin, via catalytic hydrogenation in the presence of $PtO_2$ in HOAc. Their structures were confirmed as (3S,3aR,3'R)-3a,7-dimethyl-3-(tetrahydrofuran-3-yl)-3a,4,5,6-tetrahydroisobenzofuran-1(3H)-one and (3S,3aR,2'R)-3-((R)-1-hydroxybutan-2-yl)-3a,7-dimethyl-3a,4,5,6-tetrahydroisobenzofuran-1(3H)-one on the basis of 2D NMR assignments. The $^{13}C$ NMR assignments of two quaternary carbons in the ${\alpha}$,${\beta}$-unsaturated carbonyl moiety of ${\gamma}$-butyrolactone core of fraxinellone should be revised.