• Bulletin of the Korean Chemical Society
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• v.16 no.7
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• pp.670-672
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• 1995

• YAKHAK HOEJI
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• v.30 no.3
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• pp.121-127
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• 1986

Three new alkanol esters of d-2-(6-methoxy-2-naphthyl)propionic acid, NAPROXEN were synthesized by esterification of sodium naproxen with chloralcohols, such as 2-chloroethanol, 3-chloro-1, 2-propanediol and $\beta$-chloroethoxyethanol in dimethylformamide. These new esters were obtained with comparably high yield and identified by elemental analysis, UV, IR and NMR techniques.

• Bulletin of the Korean Chemical Society
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• v.20 no.12
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• pp.1421-1427
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• 1999

4-Hydroxy-4'-methoxyazobenzene and 4-hydroxy-4'-cyanoazobenzene were synthesized from phenol with p-anisidine and p-aminobenzonitrile through a diazotization reaction, respectively. They were reacted with 2-chloroethanol, 2-(2-chloroethoxy)ethanol, or 2-[2-(2-chloroethoxy)ethoxy]ethanol to produce six kinds of new mesogenic alcohols having an azobenzene group that is sensitive to the ultraviolet. Twelve kinds of new photoresponsive monomers with two symmetrical mesogens were prepared by the reaction of the mesogenic alcohols with fumaric acid or maleic acid through a Mitsunobu reaction. The resulting monomers have different length of flexible ethyleneoxy spacer tethered to azobenzene group. The length of the spacer affected their thermal stability, solubility, and phase transition temperature. Structures of the monomers were identified by FT-IR and ¹H-NMR spectra. Their phase transition temperatures and thermal stability were also investigated by a differential scanning calorimetry (DSC) and a thermogravimetric analysis (TGA). From an optical polarizing microscopy, all the prepared monomers except fumarate-1 and maleate-1 were found to show enantiotropic liquid crystallinity with a smectic texture like focal-conic, fan-shaped, and batonnet textures.

• 보존과학연구
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• s.31
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• pp.9-16
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• 2010

The Annals of the Joseon Dynasty is one of the World Heritage which should be conserved well. However, some of wax treated volume of the Annals of the Joseon Dynasty have damaged seriously. Currently a variety of efforts to conserve and restore the injured volumes are continued and many studies about the aging mechanism of the wax treated volume have being progressed. The analysis of VOCs (Volatile Organic Compounds) emitted from paper cultural heritage is one of the methods to understand the degradation pathway of paper cultural heritage. The analysis of VOCs emitted from paper cultural heritage has been mainly conducted by SPME (Solid Phase Microextraction) method. SPME is potable and simple method but it is difficult to collect all VOCs emitted from a book such as the Annals of Joseon Dynasty. The dynamic chamber system has generally used to do analysis of VOCs emitted from the building materials, furniture and electric appliances. The chamber system is possible to do quantitative and qualitative analysis by a continuous $N_2$ gas flow and the proper chamber which is able to gather all VOCs emitted from the Annals of the Joseon Dynasty. In this study, the most material among detected VOCs was Naphthalene. Naphthalene has used to prevent organic cultural heritage from being damaged by various microbes for a long time. Apart from Naphthalene, main VOCs were Acetic acid, 2-Chloroethanol, 2-Bromoethanol, Furfural, 1-Methylnaphthalene, Azulene, and 2,4-Dioctylphenol. Of these VOCs, Furfural especially was known for a marker which represents a different emission rate according to the aging level.

• Korean Journal of Agricultural Science
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• v.9 no.2
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• pp.591-595
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• 1982

In order to know about chemical properties of a commercial organofluoro rodenticide, $Kiratol-F^{(R)}$, this experiment was carried out. Chemicals from different two manufactures were compared with synthetic compound by Gas Chromatograph and NMR-spectrophotometer. The results were as followings; 1. The permitted active ingrdient of Kiratol-F, ${\beta}$-fluoro-ethylacetate, was not identified, but ${\beta}$-fluoroethanol was a new active ingradient. 2. Kiratol-F was a water soluble liquid containing samll amounts of chloroethanol in impurity. 3. Yield of synthetic fluoroethanol was about 50%, but the composition of the reactant was assumed ${\alpha}$- and ${\beta}$-fluoroethanol, and the light condition was better than the dark in yield. 4. It was not become known any breakdown of active ingredient by the different dilutions and time intervals. So, the secondary toxicity of Kiratol-F might be relatively higher than imagination.

• Journal of the Korean Chemical Society
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• v.27 no.6
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• pp.449-456
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• 1983

The facile route of preparing S-2-(${\omega}$-aminoalkylamino) ethyl dihydrogen phosphorothioates, potential chemical radioprotectants, have been studied. Intermediate 3-(2-phthalimidoethyl)-2-oxazolidinone was prepared by a reaction of potassium phthalimide and 3-(2-bromoethyl)-2-oxazolidinone, which was obtained through the alkaline ring closure of a mixture of carbonate and 2,2'-dibromo diethylamine prepared from diethanolamine. This was converted to N-[2-(2-bromoethylamino)ethyl] phthalimide hydrobromide by 30% HBr(gas) in acetic acid and N-(2-bromoethyl)-1,2-ethanediamine dihydrobromide was obtained by reacting the hydrobromide with a solution of HBr-HOAc. N-(2-bromoethyl)-1,3-propanediamine dihydrobromide could be prepared through the Cortese treatment of 2-(3-aminopropylamino) ethanol, which was prepared by a reaction of 1,3-diaminopropane and 2-chloroethanol. These dihydrobromides were treated by sodium thiophosphate in DMF to result S-2-(${\omega}$-aminoalkylamino) ethyl dihydrogen phosphorothioates. The characteristics of each reaction path were discussed in regards to reaction conditions and overall yields and a facile route of preparing each derivative was proposed.