• YAKHAK HOEJI
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• v.40 no.6
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• pp.640-645
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• 1996

5-Alkyl-2(3H)-benzofuranones(3a-e) were prepared from Friedel-Crafts reaction of 4-alkylphenols with methyl 2-chloro-2-(methylthio)acetae(1) followed by the treatment of zinc du st-acetic acid. The reaction of disubstituted phenols with 1 in the presence of stannic chloride afforded 3-methyltWa-2(3H)-benzofuranone derivatives(11a-c), which were readily converted into 2(3H)-benzofuranone derivatives(12a-c) by desulfurization with zinc dust-acetic acid.

• Korean Journal of Pharmacognosy
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• v.14 no.1
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• pp.5-8
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• 1983

Phlomis umbrosa Turcz. ('Sok-dan') is a perennial herb in Labiatae plants. Shanzhiside methyl ester was isolated from butanol extract of this plant. It was obtained as amorphous powder and its molecular formula is $C_{17}H_{26}O_{11}$. Its structure was determined by chemical reactions, spectral analysis and compared with authentic sample of its pentaacetate.

• Natural Product Sciences
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• v.19 no.3
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• pp.221-226
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• 2013

Phytochemical investigation of the 80% MeOH extract from the leaves of Allium victorialis var. platyphyllum resulted in the isolation of seventeen compounds; two terpenes, three norsesquiterpenes, one furofuran lignan, and eleven phenolic derivatives. Their chemical structures were characterized by spectroscopic methods to be trans-phytol (1), phytene-1,2-diol (2), icariside B2 (3), (6S,9S)-roseoside (4), sedumoside G (5), pinoresinol-4-O-glucoside (6), 2-methoxy-2-(4'-hydroxyphenyl)ethanol (7), 2-hydroxy-2-(4'-hydroxyphenyl)ethanol (8), Benzyl ${\beta}$-D-glucopyranoside (9), methyl ferulate (10), trans-ferulic acid (11), methyl-p-hydroxycinnamate (12), glucosyl methyl ferulate (13), linocaffein (14), siringin (15), 2-(4-hydroxy-3-methoxyphenyl)-ethyl-O-${\beta}$-Dglucopyranoside (16), and pseudolaroside C (17). All compounds were isolated for the first time from this plant.

• Journal of Food Hygiene and Safety
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• v.9 no.4
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• pp.185-189
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• 1994

This study was to investigate time-dependent degradation process under various pH condition for organophosphorus(org-p) insecticides, namely Demeton-s-methyl, diazinon, Parathion, Phenthoate, and EPN in several waters. They were analysed by GC-FTD according to standard methods for the examination of water and wastewater. In pH=4, diazinon showed disappearance after 14 days in chromatogram. In pH=11, org-p insecticides were almost degradable after 7 days. In this condition, effect of pH on degradation process was greater than of light. In pH=7, org-p insecticides persisted residues after 112 days except Demeton-s-methyl. In BOD5 120, 250 ppm and domestic water, org-p insecticides showed also rapid degradation process.

• Natural Product Sciences
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• v.11 no.2
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• pp.75-78
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• 2005

A new acetophenone named rumexin $(3-hydroxy-5-methyl-4-O-{\beta}-D-glucopyranosyl\;acetophenone)$ was isolated from methanolic extract of Rumex aquatica together with eight known compounds, $quercetin-3-O-{\beta}-D-glucuropyranoside$, $musizin-8-O-{\beta}-D-glucopyranoside$, $quercetin-3-O-{\alpha}-L-rhamnoside$, $emodin-8-O-{\beta}- D-glucopyranoside$, caffeic acid, $1-O-caffeoyl-{\beta}-D-glucopyranoside$, 1-methyl caffeic acid, $kaempferol-3-O-{\beta}-D-glucuropyranoside$. All of the above compounds were isolated from Rumex aquatica for the first time, and structures of compounds were established by spectroscopic means.

• Natural Product Sciences
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• v.20 no.2
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• pp.86-90
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• 2014

Phytochemical investigation of the 80% MeOH extract from the leaves of Hosta longipes resulted in the isolation of sixteen compounds (1 - 16). The structures of the compounds were elucidated by spectroscopic methods to be methyl 10,10-dimethoxydecanoate (1), methyl 10-hydroxy-8E,12Z-octadecadienoate (2), methyl coriolate (3), trans-phytol (4), phytene-1,2-diol (5), phyton (6), (3S,5R,6S,7E,9R)-7-megastigmene-3,6,9-triol (7), (3S,5R,6S,9R)-3,6,9-trihydroxymegastigman-7-ene (8), shikimic acid (9), p-coumaramide (10), trans-N-p-coumaroyltyramine (11), cis-N-coumaroyltyramine (12), tryptophan (13), thymidine (14), adenosine (15), and deoxyadenosine (16). Compound 1 was synthesized, but not yet isolated from natural source, and compounds 2-16 were isolated for the first time from this plant source.

• Journal of the Korea Furniture Society
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• v.14 no.1
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• pp.11-20
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• 2003

Wood cell-wall modification with acetic anhydride, lumen filled with styren monomer and methyl methacrylate, and a combination of these two treatments were studied for their effectiveness for dimensional stability. Compared to those of untreated Pinus densiflora Sieb. et Zucc and sole acetylated red pine, The combination of acetylation and impregnation with methy methacrylate greatly reduced water absorption, increased ASE to the best and gave better bending strength and compression strength.

• Journal of the Korean Applied Science and Technology
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• v.2 no.2
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• pp.31-38
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• 1985

The transesterification reaction between ethanolamine and methyl-methacrylate was kinetically investigated in the presence of various metal acetate catalysts at $110^{\circ}C$. The transesterification was found to obey first-order kinetice with respect to the concentration of ethanolamine and methyl-methacrylate, respectively. By the Arrhenius plot, the activation energy has been calculated as 11.9 Kcal with lead acetate catalyst, 14.7 Kcal without catalyst. The reactivities has highest value where the electronegativity and instability constant (Kij) values for the metal acetate catalysts are about 1.6.

• Bulletin of the Korean Chemical Society
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• v.26 no.10
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• pp.1520-1524
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• 2005

This paper describes the racemic and stereoselective synthetic route for a novel 4'$\alpha$-phenyl and 6'$\alpha$-methyl doubly branched carbocyclic nucleosides from an acyclic 2-hydroxy acetophenone. The installation of phenyl group at the 4'-position of carbocyclic nucleoside was successfully accomplished via a sequential [3,3]-sigmatropic rearrangement. The stereoselective introduction of a methyl group in the 6'$\alpha$-position was accomplished by Felkin-Anh controlled alkylation. Bis-vinyl 11 compound was successfully cyclized using a Grubbs’ catalyst II to desired carbocycles. The natural bases (adenine and cytosine) were efficiently coupled using a Pd(0) catalyst. Although all the synthesized compounds were examined for their activity against several viruses such as HIV-1, HSV-1, HSV-2 and HCMV, only cytosine analogues 17 exhibited weak antiviral activity against HCMV.

• Journal of the Korean Society of Safety
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• v.11 no.3
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• pp.137-142
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• 1996

Combustion characteristics of immobilized methyl, ethyl and propyl alcohols on sands were studied. Experiments were performed by burning methyl, ethyl and propyl alcohols Immobilized on sands (particle size 0.1~5mm) and ceramic balls(particle size 5mm) to measure mass burning rate, height burning rate and combustion temperature. It was concluded that the longer time from ignition to extinguishment was resulted from the larger particle size of sands and the smaller size of sands exhibited the higher mass burning rate. Of alcohols tested the relative magnitude of facilitation of combustion was methyl>ethyl>propyl alcohol. Combustion temperature of alcohols, without regard to the types of alcohols, was not increased with smaller sands. However, with larger sands, combustion temperatare of alcohols was increased with the larger particle.