• 통합자연과학논문집
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• 제2권3호
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• pp.185-189
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• 2009

The new MPV-type reagent, Al-fluorodiisobutylalane (DIBAF), has been prepared and their reducing characteristics in the reduction of selected organic compounds containing representative functional groups have been examined in order to find out a new reducing system with unique applicability in organic synthesis. In general, the reagent is extremely mild, showing only reactivity toward aldehydes, ketones, and epoxides. The reagent achives a clean 1,2-reduction of enals to the corresponding allylic alcohols in a 100% purity, but shows no reactivity toward enones. The reagent also shows an excellent regioselective cleavage of substituted epoxides. In addition, DIBAF produces the thermodynamically more stable alcohol epimer in high stereoselectivity in the reduction of cyclic ketones.

• 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.

• Bulletin of the Korean Chemical Society
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• 제31권4호
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• pp.859-862
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• 2010

The reactions of ketene dithioacetals with ethane-1,2-diamine, propane-1,3-diamine, 2-aminoethanol, 3-aminopropanol, and 2-aminoethanethiol in ordinary water in the absence of any acid/base catalyst afforded the heterocyclic ketene N,N-, N,O- and N,S-acetals in good yields.

• Archives of Pharmacal Research
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• 제14권4호
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• pp.364-369
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• 1991

The synthesis and regioselective reactions of a chiral allyl sulfide. (S)-(+)-(1-methylpyrrolidin-2-yl)methyl allyl sulfide (MAS, 1) are described. Remarkable ${\alpha}-regioselectivity$ was observed in the alkylation of the carbanion of MAS while 1:3 mixtures of ${\alpha}-and\;{\gamma}-adducts$ were produced in the addition of the MAS anion to aldehydes. However, a dramatic change of the regioselectivity was witnessed when Lewis acids such as $Et_3Al$, $Et_3B$, and $Ti(O^iPr)_4$ were used as additives in the addition reaction. In these cases, ${\alpha}-adducts$ were formed exclusively. A rationale for the change of regioselectivity is provided. And the stereochemical aspect of the addition reaction is also described.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.353.2-353.2
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• 2002

5-Arylamino-6-chloro-4.7-dioxoindazoles (DZs) were newly synthesized for the evaluation of antifungal activities. The compounds DZs were prepared by regioselective nucleophilic substitution of 5.6-dichloro-4.7-dioxoindazoles with appropriate arylamines in high yield. DZs were tested for their growth inhibitory activities against Candida species and Aspergillus niger. The MIC values were determined by the two-fold dilution method. In general. DZs showed in vitro antifungal activities. Among the tested compounds, DZ1, 3, 6, 7 and 12 showed potent antifungal activities against Candida species and Aspergillus niger. DZ7 was the most effective in preventing the growth of Candida species.

• Archives of Pharmacal Research
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• 제16권1호
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• pp.75-77
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• 1993

The cycloaddition reaction of N-phenyl-C-cinnamonitrilimine 4 to coumarin leads to the for-mation of 3-styrylbenzopyrano[4,3-c]pyrazole derivative 6, whereas 3-phenylsulfonylcoumarin 9 or 3-bromocoumain 10 or 3-cyanocoumarin 11 gives 1-styrylbenzopyrano[3,4]pyrazole derivative 7. Also, the cycloaddition of 4 to 3-acetylocoumarin 15 and 3-benzoylocumain 16 gives the corresponding dihydropyrano[3,4-c]pyrazole adducts 17 and 18 respectively. Oxidation of 17 and 18 gives 7.

• 대한화학회지
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• 제43권5호
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• pp.535-539
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• 1999

Timmis반응을 이용하여 1,3-dimthyllumazine유도체를 합성하였다. 4-Amino-1,3-dimethyl-5-nitrosouracil(1)을 2,4-pentanedione, ethyl cyanoacetate, 그리고 ethyl acetoacetat와 반응시켜 6-acetyl-1,3,7-trimethyllumazine (2), ethyl 7-amino-1,3-dimethyllumazine-6-carboxylate (4), ethyl 1,3,7-trimethyl-lumazine-6-carboxylate (5)를 좋은 수율로써 합성하였다. 화합물 2,4,5의 6-아세틸 및 에스테르기에 대한 곁사슬 반응으로 다양한 1,3-dimethyllumazine 유도체들이 합성되었다. 합성된 화합물의 구조 및 물리적 특성은 NMR, UV, IR스펙트럼, 그리고 원소분석에 의하여 확인하였다.

• Archives of Pharmacal Research
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• 제21권4호
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• pp.440-444
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• 1998

A series of 6-(N-arylamino)-7-methylthio-5,8-quinolinedione derivatives 4a-4l was newly synthesized for the evaluation of antifungal activity. 6-(N-Arylamino)-7-methylthio-5,8-quinolinediones were prepared by regioselective nucleophilic substitution of 6,7-dichloro-5,8-quinolinediones with arylamines in the presence of $Ce^{3+}$, and $Na_2$S/dimethylsulfate. The MIC values of 4a-4l were determined for antifungal susceptibility in vitro against Candida species by agar streak method. The derivatives 4a-4l had generally potent antifungal activities against all human pathogenic fungi. Especially they had the most potent activity against C. krusei at 12.5-0.8 $\mu\textrm{g}$/ml. Compounds 4d, 4g, 4h, 4j and 4k had more potent antifungal activities than fluconazole. Compounds 4g and 4h completely inhibited the fungal growth at 0.8-6.3 $\mu\textrm{g}$/ml against all Candida species, while fluconazole inhibited the growth at 25 $\mu\textrm{g}$/ml. The compounds such as 4g and 4h containing an N-(4-bromo-2-methylphenyl)- or N-(4-bromo-3methylphenyl)amino substituent exhibited the most potent antifungal activities.

• 공업화학
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• 제26권2호
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• pp.132-137
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• 2015

BEA형 제올라이트를 알칼리용액으로 처리하여 결정구조 내에 메조세공이 형성되도록 제조하고, 세공 내에 균일계 키랄 Co(III) 살렌을 고정화시켰다. 메조세공 BEA-제올라이트에 고정화된 이핵형 Co-$GaCl_3$ 살렌 촉매는 말단 에폭사이드의 산소고리를 카르복실산으로 여는 키랄 반응에 대하여 높은 활성을 나타내었다. 이 반응을 통하여 라세믹 에폭사이드로부터 다양한 모노 에스테르 유도체를 중간 정도의 광학선택도(47~69 ee%)로 합성할 수 있었다. 키랄(S)-ECH를 반응물로 사용하면, 이들은 키랄 살렌 촉매 존재하에서 카르복시 산에 의하여 에폭사이드의 링이 광학선택적으로 열리며, 생성된 화합물을 염기용액에서 탈염산 처리하면 다시 에폭사이드 링이 형성되면서 광학순도가 매우 높은 모노에스터 에폭사이드 (R)-GB (98 ee% 이상)가 얻어졌다. 고정화촉매는 매우 용이하게 제조될 수 있었으며, 특별한 재생처리 없이 여러번 재사용하여도 촉매의 활성이 유지되었다.

• 약학회지
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• 제36권1호
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• pp.1-6
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• 1992

Irradiation of phenolbetaine in a stream of nitrogen produced 8,14-cycioberbine[1]. Compound[1] was treated with 10% HCl solution to give the 8-hydroxycycloberbine[2] in 67.7% yield. Subsequently addition of ethylchloroformate to the compound[2] gave rise to the 8-hydroxy-7-ethylcarboxy-9, 10-dimethoxy-2, 3-methylenelioxy-13-oxo-norochotensane[3] in 78% yield. Treatment of the compound[3] with bis-(2-chloroethyl)amine then lead to the 7-bis(2-chloroethyl)carbamyl-norochoteneare[4]. On the other hand the compound[5], which is the 8-methoxynorochotensane, was derived when compound[1] was treated with methanol in a few drops of BF. Treatment of the compound[6], and the compound[7], 7-bis(2-chloroethyl)-carbanyl-8-methoxy-norocheyensane, was then synthesized by reaction of the compound[6] with bis(2-chloroethyl) amine. In the other synthetic pathway when compound[5] was treated with $POCl_3$ in dried benzene, 13-chloro-6-ene-norochetensane[8] with 42% yield was formed. Finally the 13-bis-(2-chloroethyl) amino-8-methoxy-norochotensane[9] was produced when we treated the compound[8] with bis-(2-chloroethyl) amine. In another pathway, reaction between phenolbetaine which is the precursor of the compound[1] and benzoylchloride in dried chloroform gave us the 5,6,7 trihydro-2, 3-methylene-dioxy-9-chloromethyl-10, 11-dimethoxyphenylisoquinoline-8-benzoate[10] in 73% yield. The results of biological activities for these compounds are also presented in Table I and II.