• Bulletin of the Korean Chemical Society
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• 제28권9호
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• pp.1553-1561
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• 2007

The new type of heterometallic chiral polymer salen complexes have been synthesized and it has been found that group 13 metal salts (AlCl3, GaCl3 and InCl3) combined to cobalt salen unit played the crucial role in the asymmetric kinetic resolution of racemic epoxides. Polymeric salen catalysts showed very high reactivity and enantioselectivity for the asymmetric ring opening of terminal epoxide with diverse nucleophiles. They provide the enantiopure useful chiral intermediates such as chiral terminal epoxides and α -aryloxy alcohols in one-step process. An efficient methodology for providing very high enantioselectivity can be achieved in the synthesis of valuable chiral building blocks via our catalytic system by combination of various asymmetric ring opening reactions.

• 한국막학회:학술대회논문집
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• 한국막학회 1997년도 제5회 하계 Workshop (97 한,카 국제공동 Workshop, 고도 수처리를 위한 막분리 공정)
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• pp.1-20
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• 1997

The present standard of drinking water quality is not reached to the guidelines of WHO and US EPA recommended. The appraisal of safety is not appropriate by the results of intermittent and limitted analysis. 45 items of drinking water quality are regulated in the Korean standard and 9 items for inspection designated by Seoul City. This report is the results of analysis of the water quality in the water stations of Seoul which are concerned with the items of Korean water quality standard and the priolity pollutnats recommended by WHO. In the results, 45 items of water quality, and the priolity pollutants were not exceeded to the standard and criteria, while DDT, heptachlor-epoxide, THMs, benzo(a)pyrene, Ba, Al, Gross beta, $^{226}$Ra, $^{90}$Sr were detected, the levels were not exceeded to the WHO guidelines. In ordes to evalute the safety of drinking water quality, besides of the existed items of standard, new hazardouse pollutants should be considered monitored continenously. For the regulation of hazardous pollutants, it may be introduced from the risk assessment. According to the relevant assessment, the acceptable risk of pollutants estimated could be applied to set the water quality standard or recommendations or quidelines as well as the number of monitoring.

• Bulletin of the Korean Chemical Society
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• 제31권10호
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• pp.2973-2979
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• 2010

The newly synthesized homogeneous chiral Co(III) salen complexes were anchored non-covalently on the acidic sites of mesoporous Al-SBA-15. The Bronsted and Lewis acidic sites are attributed to the immobilization of fluorine functionalized chiral salen complexes on the supports. XRD, BET, TEM, FT-IR and ESCA (XPS) analyses were performed to characterize the property of support, and the structure of new homogeneous and heterogeneous chiral Co salen catalyst. The homogeneous and heterogeneous catalysts could be applied in asymmetric ring opening of epichlorohydrine (ECH) by water. They showed very high enantioselectivity and a good yield up to 99% in the catalytic synthesis of optically active products.

• 한국환경성돌연변이발암원학회:학술대회논문집
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• 한국환경성돌연변이발암원학회 2002년도 Current Trends in Toxicological Sciences
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• pp.134-134
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• 2002

• Carbon letters
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• 제13권1호
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• pp.29-33
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• 2012

A novel strategy for the simultaneous reduction and functionalization of graphene oxide (G-O) was developed using polyallylamine hydrochloride (PAAH) as a multi-functional agent. The G-O functionalization by PAAH was carried out under basic conditions to catalyze the epoxide ring opening reaction of G-O with abundant amine groups of PAAH. We found that G-O was not only functionalized with PAAH but also reduced under the reaction condition. Moreover, the synthesized PAAH-functionalized G-O sheets were soluble in water and applicable to the synthesis of nanocomposites with gold nanoparticles.

• Bulletin of the Korean Chemical Society
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• 제25권6호
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• pp.881-888
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• 2004

By applying a catalytic amount of indium trichloride, regioselective ring-opening of epoxides to ${\beta}$-hydroxy ethers was established. While the alcoholysis of styrene oxides produed $S_N1$-type product, the alcoholysis of ${\alpha}$-heteroatom-substituted epoxides predominantly produced $S_N2$-type product.

• Bulletin of the Korean Chemical Society
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• 제26권6호
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• pp.959-965
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• 2005

Investigation of structure-activity relationships of novel quinazolines has identified 7,8-dihydro-[1,4]dioxino-[2,3-g]quinazolines as a potent inhibitor of EGFR. These compounds have a benzodioxane framwork, which was prepared by regioselective O-alkylation of ethyl 3,4-dihydroxy benzoate by epoxide ring opening. Compounds 3f and 3k were more potent than ZD-1839 in EGF enzyme and EGFR autophosporylation inhibition assays.

• 약학회지
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• 제56권4호
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• pp.230-235
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• 2012

Synthesis of novel cyclopropyl pyrimidine and purine nucleoside derivatives 2~8 with ${\alpha}$-configuration was successfully accomplished using an epoxide-ring opening reaction, lactonization, a hydroboration-oxidation reaction and a Mitsunobu reaction as the key steps. Antiviral activities against HSV-1 and -2, HIV-1 and -2, coxsackie B1and B3 viruses and poliovirus were assayed. Three compounds 4, 7 and 8 exhibit cytotoxicity-derived antiviral activity only in HIV-1 and -2.

• 약학회지
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• 제18권1호
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• pp.29-38
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• 1974

In order to study the residual amounts of absorbed organochlorine pasticides in vegetables, heptachlor and endrin were sprayed 2,4 and 6kg per 10a., respectively, before sowing the seeds in the station. The experiemental study is primarily concerned with the absorption in lettuce nad garland chrysanthemum. The absorption of each pesticide into lettuce and garland chrysanthemum, and residual pesticides in soil by timne have been analyzed by the gas chromtographic method, and the ratio of residual pesticides in vegetablesand soil were estimated. Heptachlor, heptachlor epoxide and endrin in lettuce nad garland chrysanthemum at the market in Seoul area hvae also analyzed and found extremely low level of pesticides in comparison with the level in above experimental vegetables as well as same vegetables in Japan.

• Bulletin of the Korean Chemical Society
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• 제28권11호
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• pp.2051-2055
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• 2007

The solvent effect on sulfur ylide mediated epoxidation reaction was studied systematically. While higher trans/cis ratio of the epoxide was obtained in the more polar solvent, protic solvent produced the lower trans/ cis ratio than any aprotic solvent.