• YAKHAK HOEJI
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• v.43 no.5
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• pp.547-552
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• 1999

Phytochemical examination of the leaves of Alnus hirsuta, one of the indigenous species grows in Korea, has led to the isolation of one flavan 3-ol and two flavonol glycosides. Structures of these compounds are identified as (-)-epicatechin (1), quercetin $3-O-{\beta}-D-galactopyranoside$ (2), quercetin $3-O-{\beta}-D-galactopyranoside$ (3) by means of physico-chemical and spectral evidences.

• 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.

• Archives of Pharmacal Research
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• v.29 no.2
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• pp.135-139
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• 2006

Activity-guided fractionation of the ethanol extract of the whole plant from Solanum lyratum resulted in the isolation of a new pregnane derivative glycoside, 16-dehydropregnenolone 3-O-${\alpha}$-L-rhamnopyranosyl-($1{\to}2$)-${\beta}$-D-glucopyranosid uronic acid (2), as well as other six known compounds: 16-dehydropregnenolone (1), allopregenolone (3), protocatechuic acid (4), vanillic acid (5), caffeic acid (6), and scopoletin (7). The structures of the isolated compounds were elucidated on the basis of their spectral data and chemical evidences. Compounds 1, 3, 4 were isolated for the first time from this plant. Cytotoxic activities of the isolated compounds were evaluated. Compound 1 exhibited significant cytotoxic activity against A375-S2, HeLa, SGC-7901, and Bel-7402 with $IC_{50}$ values of $13.1{\pm}0.9,\;21.5{\pm}1.0,\;40.2{\pm}0.7$, and $49.8{\pm}1.2\;{\mu}g/mL$, respectively.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.477-483
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• 2023

The flowers of Carthamus tinctorius (Safflower) were extracted with 80% aqueous methanol (CTex) and the concentrates were partitioned into EtOAc (CTE), n-BuOH (CTB), and H₂O (CTW) fractions. Repeated silica gel (SiO₂) and octadecyl silica gel column chromatographies for the EtOAc and n-BuOH fractions led to isolation of four flavonol glycosides. Nuclear magnetic resornance, infrarad spectroscopy, and mass spectroscopy revealed the chemical structure of the isolated compounds, astragalin (1), isoquercetin (2), nicotiflorin (3), and rutin (4). Quantitative analysis of four isolated compounds in CTex was performed by HPLC. CTex was found to contain 1 at 0.107, 2 at 0.367, 3 at 6.752, and 4 at 0.991 mg/g, respectively. Through this study, an experiment was conducted to evaluate the protective effect on pancreatic islets of the extract, solvent fractions, and all isolated compounds using a zebrafish larvae damaged by alloxan. Pancreatic islet size treated with EtOAc (CTE), n-BuOH (CTB), and H₂O (CTW) fractions and compounds 1-4 significantly increased compared to the alloxan-induced group. These results indicate that C. tinctorius flowers and its isolated compounds are used as potential anti-diabetic agents.

• Journal of the Korean Chemical Society
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• v.54 no.6
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• pp.731-736
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• 2010

Several new 5-aryl-3-($\beta$-D-glucopyranosylthio)-1,2,4-triazoles have been synthesized. The structures of these new compounds were confirmed by $^1H$ NMR, $^{13}C$ NMR and elemental analyses.The antibacterial activities of the compounds were also evaluated.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.1
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• pp.1-8
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• 2003

With current developments in enzyme-catalyzed reactions and techniques available for rational redesign of natural biocatalysts, the enzymatic biosynthesis can become one of the most valuable Synthetic methods. Enzymatic regioselective catalysis in organic media has played a key role in pursuing asymmetric synthesis for active chiral compounds. Here, we shortly do-scribe some historical issues of the rapidly growing area, enzymatic catalysis in synthetic organic chemistry and then review researches that have been carried out in the regioselective enzymatic catalysis for the past two decades. An application of this technology to the modification of some potential target drug co m pound will be adios presented.

• Natural Product Sciences
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• v.23 no.4
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• pp.253-257
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• 2017

The phytochemical study for the extract of Nelumbo nucifera (Nymphaceae) seeds has led to the isolation of ten compounds including five simple phenolic compounds, two indole derivatives, a flavonoid glycoside, two abscisic acid derivatives. The interpretation of 1D and 2D NMR and ESI-Q-TOF-MS spectroscopic data revealed the chemical structures of isolates to be p-hydroxybenzoic acid (1), protocatechuic acid (2), (E)-p-coumaric acid (3), (E)-ferulic acid (4), (E)-sinapate-4-O-${\beta}$-$\text\tiny{D}$-glucopyranoside (5), tryptophan (6), 3-indoleacetic acid (7), isoschaftoside (8), dihydrophaseic acid (9), dihydrophaseic acid 3'-O-${\beta}$-$\text\tiny{D}$-glucopyranoside (10). To the best of our knowledge, 1 - 5 and 7 were identified for the first time from N. nucifera seeds, and the presence of dihydrophaseic acid (9) and its glucoside (10) were demonstrated secondly in this plant.

• Natural Product Sciences
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• v.14 no.1
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• pp.56-61
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• 2008

Bioactivity guided phytochemical study of the petroleum ether and butanol extracts of Clematis hirsuta resulted in the isolation of 12 compounds. Rat paw edema as a model of acute inflammation was used to evaluate the anti-inflammatory activity of the extracts and the chromatographic fractions. Five known sterols and triterpenes namely: ${\beta}-amyrin$ (1), lupeol (2), ${\beta}-sitosterol$ (3), oleanolic acid (4) and stigmasterol glycoside (5) were isolated from the petroleum ether extract. The n-butanol extract afforded two compounds reported for the first time from natural source: (S)-(+)-dihydro-5-(hydroxymethyl)-2(3H)-furanone (7) and (s)-(-)-5-hydroxymethyl-2(5H)-furanone (8). In addition, anemonin (6), dihydro-4-hydroxy-5-(hydroxymethyl)-2(3H)-furanone (2-deoxy-D-ribono-1,4-lactone) (9), biophenol (cimidahurin) (10), glucose (11) and sucrose (12) were also identified. The structures were determined from spectroscopic data including 1D- and 2D-NMR experiments.

• YAKHAK HOEJI
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• v.45 no.6
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• pp.591-598
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• 2001

The photochemical study of Viscum album (Loranthaceae) led to the isolation of twelve compounds, lupeol (1), betulonic acid (2), betulinic acid (3), terminic acid (4), ursolic acid (5), $\beta$-sitosterol (6), $\alpha$- spinasterol (7), oleanolic acid (8) , 5-hydroxy-1- (4′-hydoxyphenyl) -7- (4"-hydroxyphenyl) -hepta-1- en-3-on (9), 2′-hydroxy -4′, 6′- dimethoxychalcone -4-O-glycoside (10) ,2′-hydroxy-4′, 6′-dimethoxychalcone -4-O- [apiosal(1longrightarrow12)]glucoside (11) and syringin (12). Their structures were established by chemical and spectroscopic methods. The cytotoxicity of the isolated compounds was evaluated by sulforhodamine B assay against five cultured human tumor cell lines.

• Journal of the Korean Wood Science and Technology
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• v.31 no.4
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• pp.16-23
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• 2003

Four flavonoids were isolated from the heartwood of Prunus sargentii. The structures were identified by NMR spectroscopic analysis: prunetin as isoflavone, angophorol, and sakuranetin as flavanone, and isosakuranin as flavanone glycoside. However, these compounds indicated low antifungal and antioxidative activities. In this regard, it could suggest that high antifungal and antioxidative activities of extractives of P. sargentii have no ralationship with these compounds.