• Journal of the Korean Wood Science and Technology
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• v.41 no.3
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• pp.234-246
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• 2013

It was found that test piece heated rapidly by 3 kW microwave for 5 minutes satisfies the targeted temperature and the percentage of moisture content, and the highest rate of weight increase is obtained in case of 120 minute immersion in the mixture of phosphates and heterocyclic compounds, from the result of such analysis as: kiln drying schedule, flame retardent by flammability test, insect resistance by termites, and permeability of combined penetrant for the wood after assigning multifunctional finish by immersing conifer structural frame, which is used for the frame work of wooden house and indoor/outdoor finishing in flame retardant and insect repellent materials mixture with the remaining heat of microwave. In addition, after a test of flame retardent treated item, it was identified that every mixture of phosphates corresponds with the standards of flame retardent, and upon investigation of moritality of 7 days after putting termites, it was showed that test piece immersed in the mixture of phosphates and heterocyclic compounds has the best characteristics, showing over 96% of high moritality. From the analysis of inward permeability of combined penetrant for the wood, it was decided that excellent performance in the flame retardent and insect resistance of the wood revealed due to full penetration of combined penetrant as it was found that combined penetrant penetrated through the whole inner cells of the wood.

• Journal of the Korean Chemical Society
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• v.51 no.6
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• pp.506-512
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• 2007

Various long chain aliphatic acid hydrazides react with aromatic and heterocyclic aldehydes in alcoholic medium in refluxing conditions to give corresponding 2-hydroxy benzylidene and 1H-indol-3-ylmethylene hydrazides, a newer class of mosquito para-pheromones. We describe here synthesis of various novel long chain aliphatic acid (2- hydroxy benzylidene and 1H-indol-3-ylmethylene) hydrazides by conventional as well as microwave irradiation techniques. The structures of these compounds have been confirmed by spectroscopic techniques (FTIR, NMR & MS). Some of the interesting features of the electron impact mass spectral fragmentation pattern of these compounds have also been discussed.

• Journal of the Korean Chemical Society
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• v.24 no.3
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• pp.225-232
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• 1980

The electronic states of chemical carcinogens such as polycyclic aromatic hydrocarbons, heterocyclic compounds and dimethylaminoazobenzene (DAB) and its derivatives were examined and discussed for their carcinogenicity by means of simple Huckel method.The compounds which are 0.5 or more in the value of the sum of frontier electron density for nucleophilic reaction of the two atoms of K-region and that of the atom of L-region in the proximity of K-region were found to be agreed well with experimental results for carcinogenic activity. It is therefore suggested that both the K-region and the L-region play an important role in the formation of the molecular complex which was shown to be obtained in the combination of chemical carcinogen with cellular component in the first step of carcinogenesis.

• Journal of the Korean Chemical Society
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• v.42 no.4
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• pp.449-453
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• 1998

The reaction of 6-chloro-2-hydrazinoquinoxaline 4-oxide (11) with ethyl chloroglyoxylate provided ethyl 8-chloro-4H-1,3,4-oxadiazino[5,6-b]quinoxaline-2-carboxylate (12) through the intramolecular cyclization. The reaction of 12 with hydrazine hydrate afforded the $C_2$-hydrazinocarbonyl derivative 13, whose reactions with substituted benzaldehydes or heteroaryl aldehydes provided 8-chloro-2-(substituted benzylidenehydrazinocarbonyl)-4H-1,3,4-oxadiazino[5,6-b]quinoxalines (14) or 8-chloro-2-[(2-substituted methylidene)hydrazinocarbonyl]-4H-1,3,4-oxadiazino[5,6-b]quinoxalines(15), respectively.

• Journal of the Korean Chemical Society
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• v.54 no.4
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• pp.414-418
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• 2010

Ethyl 1-aminotetrazole-5-carboxylate (1) reacted with hydrazine hydrate to give the corresponding aminohydrazide 2. Cyclization of 2 by carbon disulfide yielded 1,3,4-oxadiazole-5-thiol structure 3. Reaction of 3 with either chloroacetone or ethyl chloroacetate furnished S-acyl 1,3,4-oxadiazole derivatives 4 and 5, respectively. Also compound 3 reacted with hydrazine hydrate afforded 4-amino-1,2,4-triazole-5-thiol derivative 6. 6-Methyl-1,3,4-triazolo[3,4-b]-1,3,4-thiadiazole structure 7 was synthesized by reaction of aminothiol 6 with glacial acetic acid. Diazotization of 1 with sodium nitrite in presence of hydrochloric acid yielding the diazonium salt which on treating with hippuric acid, oxazolone derivative 8 was obtained. Furthermore, tetrazolo[5,1-f]-1,2,4-triazine 9 was constructed via cyclization of aminoester 1 with formamide. Compound 9 reacted with carbon disulfide to furnish 8-thione derivative 10 which reacting with chloroacetone, ethyl chloroacetate, and hydrazine hydrate, the corresponding chemical structures 11, 12, and 13 were synthesized. 1,2,4-Triazolo[4,3-d]tetrazolo[5,1-f]-1,2,4-triazines 14 and 15 were resulted by treating of compound 13 with triethyl orthoformate, and glacial acetic acid, respectively. The structures of the newly synthesized products were elucidated according to elemental analyses and spectroscopic evidences. Some of the representative members of the prepared compounds were screened for antimicrobial activity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.1
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• pp.499-505
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• 2013

Cr(VI)-4-(dimethylamino)pyridine[4-(dimethylamino)pyridinium chlorochromate] was synthesized by the reaction of 4-(dimethylamino)pyridine with chromium trioxide in 6M-HCl, and characterized by IR, ICP. The oxidation of benzyl alcohol using 4-(dimethylamino)pyridinium chlorochromate in various solvents showed that the reactivity increased with the increase of the dielectric constant(${\varepsilon}$), in the order: cyclohexene$H_2SO_4$ solution), 4-(dimethylamino)pyridinium chlorochromate oxidized benzyl alcohol and its derivatives(p-$OCH_3$, m-$CH_3$, H, m-$OCH_3$, m-Cl, m-$NO_2$) smoothly in DMF. Electron-donating substituents accelerated the reaction, whereas electron acceptor groups retarded the reaction. The Hammett reaction constant(${\rho}$) was -0.68(303K). The observed experimental data was used to rationalize the hydride ion transfer in the rate-determining step.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.21-25
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• 2002

The contribution of lipid to thermal flayer generation from glucose-protein reaction was accomplished by isolating flavor compounds from casein-glucose (CG)and casein-glucose-coin oil (CGL) which were stored for 2 and 4 weeks at 6$0^{\circ}C$ and then reacted at 16$0^{\circ}C$ for 1hr. The volatiles from the reactant mixtures were isolated by a solvent extraction method with methylene chloride and analyzed by gas chromatography and gas chromatography-mass spectrometry. Pyrazine, methylpyrazine, 2,5-dimethylpyrazine, 2-dimethylpyrazine ,2-ethy-5- methyIpyrazine and 2-acetylpyrrole originated from interaction of thermal degradation of casein and lipid oxidation were identified in the CGL samples. It was also found that 3-methyl-1-butanol, 2-cyclopene-1,4-diode, heptanal, nonanal, and 2-heptanone were derived from lipid source. Two additional fatty acids, heptanoic acid and octanoic acid were also identified in the CGL samples. 5-Hydroxymethyl-2-furfural, the most abundant volatile, was responsible for the formation of sugar degradation product. The results suggested that the presence of lipid in the samples had more effect on the contribution of volatile formation of glucose-protein thermal reaction than the absence of lipid in the samples.

• Journal of the Korean Chemical Society
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• v.38 no.9
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• pp.676-681
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• 1994

Diels-Alder adducts, carbacephems were obtained when 4-acetoxyazetidine-2-one or (3R,4R)-4-acetoxy-3-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]azetidin-2-one was reacted with 2-(tert-butyldimethylsilyloxy)-1,3-butadiene or with 3-(tert-butyldimethylsilyloxy)-1,3-pentadiene. When tert-butyldiemethylsilyl acrylate was used as the diene, products in which was acetoxy group of 4-acetoxyazetidin-2-one derivatives was substituted by an acryloyloxy group were isolated. When the same reaction was carried out with 4-phenylsulfonylazetidin-2-one as a dienophile with 2-(tert-butyldimethylsilyloxy)-1,3-butadiene, 4-phenylsulfoyl-2-butanone was obtained instead of the expected carbacephem. When dimeric form of thiochalcone was reacted with 4-acetoxyazetidin-2-one in the presence of zinc chloride, the $\beta-lactam$ ring of the azetidin-2-one was destructed and no product was isolated. Also, the reaction of 2-trimethylsilyloxy-1-aza-1,3-butadiene, which was obtained from N-methylacrylamide by treatment of trimethylsilyl trifluoromethanesulfonate in the presence of triethylamine, with 4-acetoxyazetidin-2-one did not give any products.

• Journal of the Korean Chemical Society
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• v.55 no.4
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• pp.638-643
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• 2011

The synthesis of biologically active 1H-1,4-diazepines 4a-d and 3H-1,5-benzodiazepines 5a-d in good yields, from the heterocyclization reaction of 2-(4-methylthio benzenesulfonyl)-1,3-dimethyl/1-methyl-3-phenyl/1,3-diphenyl/1-methyl-3-ethoxy propane-1,3-dione 3a-d with ethylenediamine (EDA) and o-phenylenediamine (o-PDA), respectively, in the presence of silica sulfuric acid (SSA) is described. The novel ${\beta}$-diketones/${\beta}$-ketoesters 3a-d were synthesized by the condensation reaction of 4-methylthiobenzenesulfonyl chloride 1 with various ${\beta}$-diketones/${\beta}$-ketoesters 2a-d. All structures of the newly synthesized compounds were elucidated by elemental analysis and spectral studies. The compounds 4a-d and 5a-d have been screened for antimicrobial, antifungal and anthelmintic activity.

• Transactions of the Korean hydrogen and new energy society
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• v.33 no.4
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• pp.372-382
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• 2022

In this study, anion exchange membranes were prepared by synthesizing the main chain into a poly(arylene ether) (PAE) structure, and the structures capable of improving the physical and chemical stability of the membrane by introducing a heterocyclic quaternary ammonium functional groups were studied. The chemical structure and thermal properties of the prepared polymer were confirmed by ¹H-NMR, FT-IR, TGA, and DSC, and surface analysis was performed through AFM measurement. Additionally, dimensional stability and chemical properties was studied by measuring water uptake and swelling ratio, IEC and ionic conductivity. At 90℃, the quaternized poly(arylene ether) (QPAE)/1-methylpiperidine (MP) membrane exhibited the highest ionic conductivity of 27.2 mS cm^-1, while the QPAE/1-methylimidazole (MI) membrane and QPAE/1-methylmorpholine (MM) membrane exhibited values of 14.5 mS cm^-1 and 11.5 mS cm^-1, respectively. In addition, the prepared anion exchange membrane exhibited high chemical stability in alkaline solution.