• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.3
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• pp.302-307
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• 1992

The methanol extract of perilla leaves contained compounds to reduce the mutagenicity of aflatoxin B$_1$(AFB$_1$) in Salmonella typhimurium TA98 and 100. They were separated by solvent extractions and identified by GC and GC-MS as 2-ethoxy acetate, 1, 2, 3, 4-tetramethyl-cis-cyclobutene, two isomers of methyl 11, 14, 17-eicosatrienoate, 12-acetyl-9-octadecanoic acid, and phytol. The antimutagenicities of phytol and methyl 11, 14, 17-eicosatrienoate were dependent on the mutagens tested. Phytol reduced the mutagenicity of Trp-p-2 but not of AFB$_1$and methyl 11, 14, 17-eicosatrienoate reduced the activities both of the mutagens.

• Korean Journal of Agricultural Science
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• v.19 no.1
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• pp.103-114
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• 1992

Screening for antioxidative activities of 180 species of crude drugs were performed on their methanol extracts. More than 45% of those showed some effect on oxidative stability of linoleic acid, and 44 species seemed to have rather strong antioxidative activity. Selected these samples of the active crude drugs were further examined in their methanol extracts with methyl linoleate emulsion system. especially 11 species revealed strong antioxidative activity. These 11 species were then successively extracted with ethyl acetate and petroleum ether, and their antioxidative activity was determined. The ethyl acetate and petroleum ether extracts of Epimedium Koreanum NAKAI, Psoralea Corylifolia L., Syringa Dilata NAKAI and Prunus mume Sieb, et Zucc. showed much more effective than the others in stabilizing methyl linoleate. Scutellaria baicalensis George. Glycyrrhiza glabra L. were only effective in the methanol extract.

• YAKHAK HOEJI
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• v.13 no.1
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• pp.47-50
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• 1969

The ether extract of Dang-Gui, the dried root of Angelica gigas N$_{AKAI}$, was placed into a column with aluminium oxide gel. The elution of it with a mixture of n-hexane and ethyl acetate afforded Nodakenetin (I) and the elution with a mixture of n-hexane, ethyl acetate, acetone and methyl alcohol yielded Umbelliferon (II) and Nodakenin (III). Three coumarin derivatives were identified by comparing with authentic samples. The existence of sucrose and glucose was also proved.

• Bulletin of the Korean Chemical Society
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• v.33 no.6
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• pp.1900-1906
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• 2012

Three carbazole chromophores featuring dicyano, cyano, ethyl acetate and dimethyl acetate groups as an acceptor moiety with a ${\pi}$-conjugated spacer and $N$-methyl dibenzo[$b$]pyrole as donor were synthesized by Knovenagel condensation and characterized by IR, $^1HNMR$, $^{13}CNMR$, UV-vis, fluorescence spectroscopy, electrochemistry and theoretical B3LYP/6-$311G^*$ level whilst NLO properties and spectroscopic quantities were calculated. Calculations showed remarkable trend with HOMO located on the donor moiety and LUMO on the acceptors dicyano methylene, cyano, ethyl acetate methylene and dimethyl acetate methylene. In agreement with the calculations, solvatochromic, behavior intramolecular charge transfer band was observed in the visible region.

• YAKHAK HOEJI
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• v.25 no.2
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• pp.43-47
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• 1981

In an attempt to obtain a saponin antigen, ginsenoside Rg$_{1}$ of Korean ginseng was condensed with bovine serum albumin through a series of modification in the side chain structure of ginsenoside Rg$_{1}$ to prepare a reactive intermediate $Rg_{1}$ azide. The modification of ginsenoside $Rg_{1}$[1] yielded $Rg_{1}$ decacetate [II], mp 252, $Rg_{1}$ acetate-glycol [III], mp 263, $Rg_{1}$ acetate-trisnoraldehyde [IV], mp 231, $Rg_{1}$ acetate-carboxylic acid [V], mp 282, $Rg_{1}$ acetate-methyl ester [VI], mp 271, $Rg_{1}$ hydrazide [VII], mp 220, and finally a reactive intermediate $Rg_{1}$ azide [VIII].

• Bulletin of the Korean Chemical Society
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• v.16 no.3
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• pp.252-256
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• 1995

Semiempirical MO calculations using the PM3 method are performed on the reactions of acetate esters with substituted phenolate anions. The mechanistic change from rate-limiting formation to breakdown of the anionic intermediate is shown to occur in the gas-phase, especially for meta-nitrophenyl acetate. However the mechanistic change-over takes place at a lower basicity ($pK_0$) of the anion nucleophile than found for the corresponding formate. This lowering of $pK_0$ has been ascribed to the electron donating effect of the methyl group in the acetate. For the reactions involving rate-limiting breakdown of the intermediate, the large Bronsted coefficients, ${\beta}_X({\beta}_{nuc})$, are expected in general, but the magnitude increases to a larger value and the pK0 is lowered accordingly, when an electron-donating nonleaving group, like $CH_3$, is present. This type of nonleaving group effect provides a necessary condition for the carbonyl addition-elimination mechanism with rate-limiting breakdown of the intermediate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.885-891
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• 2005

The study was carried out to find the effect of freeze drying on the volatile organic components in garlic (Allium sativum L.). The volatile organic compounds from fresh and freeze dried garlic were extracted by simultaneous steam distillation and extraction (SDE) method and identified with GC/MS analysis. A total of 42 and 32 compounds were identified in fresh and freeze-dried garlic, respectively. Sulfur containing compounds in the garlic samples were detected as the major compounds, and alcohols, aldehydes and esters were detected as minor compounds. Diallyl disulfide, diallyl trisulfide, allyl methyl disulfide and ally1 methyl trisulfide were the main sulfur compounds in fresh and freeze dried garlic. The amount of sulfur containing compounds were decreased freeze-drying but methyl propyl trisulide, 3- allylthiopropionic acid, cyclopentyl ethyl sulfide etc. were increased. The others, non- sulfur containing compounds such as ethyl acetate, ethanol, 2-propenol, 2- propenal and hexanal were increased in freeze-dried garlic. Consequently, the total amount of volatile organic compounds in garlic became lower during freeze-drying from 853.42 mg/kg to 802.21 /kg, and the composition of major components were nearly same in fresh and freeze-dried garlic.

• Archives of Pharmacal Research
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• v.21 no.6
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• pp.723-728
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• 1998

The chemical behaviours of 4-methyl-2-oxo-2H-benzopyran-7-yl oxoacetyl hydrazine (2) towards some different reagents such as anhydride compounds, aromatic aldehydes, carb on disulphide, and nitrous acid yielded the corresponding pathalazine derivatives (3, 4, 5), hydrazone derivative (6), 1,3,4-oxadiazole derivative (7, 8, 9) and acid azide (10) respectively. Treatmen of 10 with absolute alcohols, amines and ethyl amino acid ester gave the corresponding carbamate derivative (11), substituted urea derivative (12) and ethyl substituted alkyl acetate (13) respectively. The biological activity of some synthesized compounds was evaluated.

• YAKHAK HOEJI
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• v.48 no.1
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• pp.65-69
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• 2004

The chromatographic separation of MeOH extract of the aerial parts of Aster glehni (Compositae) led to the isolation of three sesquiterpenes, two sterols and four terpenes. Their structures were determined to be $\beta$-amyrin acetate (1), phytol (2), alismol (3), $\alpha$-tocopheryl quinone (4), $\alpha$-spinasterol (5), 10-O-methyl alismoxide (6), alismoxide (7), and 3-O-(6'-O-palmitoyl-$\beta$-D-glucosyl)-spinasta 7,22-diene (8) by physicochemical and spectroscopic methods . These compounds (1-8) were first isolated from the Aster glehni.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.249-261
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• 2006

Fifty compounds such as ester, sulfonyl ester, carbamate, ether and phosphoyl ester derivatives of 4-isopropyl-3-methylphenol(I) and 5-isopropyl-3-methylphenol(II) were synthesized. These derivatives were identified by IR, GC/MS and $^1H$-NMR spectra. Their in vitro antifungal activities were tested against 10 plant pathogenic fungi. Among them, several compounds showed potent in vitro antifungal activity. The selected compounds showing potent in vitro antifungal activity were tested for their in vivo antifungal activities against 5 plant diseases such as rice blast, rice sheath blast, cucumber anthracnose, cucumber gray mold and tomato late blight. As a result, 4-isopropyl-3-methylphenyl(2-amino-thiazole-4-yl)methoxyiminoacetate(I-7a) showed a potent in vivo antifungal activity against rice blast. Both methyl (4-isopropyl-3-methylphenoxy)acetate(I-4d) and methyl (5-isopropyl-3-methylphenoxy)acetate(II-4d) effectively inhibited the development of cucumber gray mold.