• 한국미생물·생명공학회지
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• 제20권1호
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• pp.61-67
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• 1992

유기용매 이상계에서의 thermolysin을 사용하여 아스파탐 전구체 합성시 pH, 온도, 기질농도, 그리고 유기용매상에 대한 수용액상의 부비피 ($\alpha$)등의 변화에 따른 기질의 분해 반응, 효소의 안정성, 그리고 Z-APM 합성에 미치는 복합적인 영향을 조사함으로써 반응조건의 최적화를 도모하였다. 유기용매 이상계에서의 L-PM.HCL의 자연분해는 수용액에서보다 훨씬 느리게 일어나며, 또한 $\alpha$가 증가할 수록 분해속도가 감소하는 것을 알 수 있었다.

• 대한화학회지
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• 제59권1호
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• pp.31-35
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• 2015

Diastereoselective reduction of 2,3-dioxo-4-carboxy-5-(substituted)pyrrolidine 1 by $NaBH_4/AcOH$ and heterogenous hydrogenation were reported. Stereochemical assignment and diastereomeric ratios of the products were determined using $^1H$ NMR and single crystal X-ray analyses. The steric factors of the C-5 substituents of the pyrrolidinone was shown to have an interesting influence on both the yield and diastereoselectivity of the reduced product.

• Bulletin of the Korean Chemical Society
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• 제35권2호
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• pp.521-524
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• 2014

Pyronaridine tetraphosphate (1) is a well-known antimalarial drug. However, it required a carefully optimized production process for the manufacture of pyronaridine tetraphosphate. Each step of its manufacturing process was reinvestigated. For the cyclization of 4-chloro-2-(6-methoxy-pyridin-3-yl-amino)-benzoic acid 6 to 7,10-dichloro-2-methoxybenzo[b]-1,5-naphthyridine 5, an improved process was developed to eliminated critical process impurity (BIA). By the redesign of the formation of triphosphate salt, the purity as API grade was increased. Thus, a robust manufacturing process with an acceptable process performance has been developed to produce high quality pyronaridine tetraphosphate.

• Bulletin of the Korean Chemical Society
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• 제31권4호
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• pp.840-844
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• 2010

The new MPV type reagent, Al-methanesulfonyldiisobutylalane ($DIBAO_3SCH_3$), has been prepared and its 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 high selectivity in organic synthesis. In general, the reagent is extremely mild, showing only reactivity toward aldehydes, ketones and epoxides. The reagent exhibits a unique reducing applicability in organic synthesis. Thus, the reagent can achieve a clean 1,2-reduction of $\alpha,\beta$-unsaturated aldehydes and ketones to produce the corresponding allylic alcohols in 100% purity. In addition, the reagent shows an excellent regioselectivity in the ring-opening reaction of epoxides. Finally, $DIBAO_3SCH_3$ shows a high stereoselectivity in the reduction of cyclic ketones to produce the thermodynamically more stable epimers exclusively.

• Bulletin of the Korean Chemical Society
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• 제30권12호
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• pp.2883-2886
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• 2009

A simple, highly efficient and environmentally benign method for the synthesis of 3-styrylchromones from 3-formylchromones and 4-nitrophenylacetic acid/4-nitrotolune in the presence of catalytic amount of basic ionic liquid 1-butyl-3-methylimidazolium hydroxide [(bmim)OH] carried out under the influence of microwave irradiation. This method gives remarkable advantages such as, short reaction times, simple work-up procedure and moderate to good yields. The ionic liquid was successfully reused for four cycles without significant loss of activity.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2007년도 학술발표회 논문집
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• pp.195-196
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• 2007

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• 한국세라믹학회지
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• 제54권4호
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• pp.272-277
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• 2017

Organic-inorganic hybrid thermoelectric materials have obtained increasing attention because it opens the possibility of enhancing thermoelectric performance by utilizing the low thermal conductivity of organic thermoelectric materials and the high Seebeck coefficient of inorganic thermoelectric materials. Moreover, the organic-inorganic hybrid thermoelectric materials possess numerous advantages, including functional aspects such as flexibility or transparency, low cost raw materials, and simplified fabrication processes, thus, allowing for a wide range of potential applications. In this study, the types and synthesis methods of organic-inorganic thermoelectric hybrid materials were discussed along with the methods used to enhance their thermoelectric properties. As a key factor to maximize the thermoelectric performances of hybrid thermoelectric materials, the nanoengineering to control the nanostructure of the inorganic materials as well as the modification of the organic material structure and doping level are considered, respectively. Meanwhile, the interface between the inorganic and organic phase is also important to develop the hybrid thermoelectric module with excellent reliability and high thermoelectric efficiency in addition to its performance in various electronic devices.

• 대한화학회지
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• 제38권6호
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• pp.449-455
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• 1994

효소를 이용한 생리활성 펩티드의 합성 연구에 관한 기초자료를 얻기 위하여, Kyotorphin(진통작용을 가진 펩티드) 유도체가 $\alpha-chymotrysin$를 이용한 이상계(two phase system;유기상과 수용액상)조건하에서 Ac-Tyr-OH 와 $Arg-NH_2$로부터 합성되었다. Ac-Tyr-OH(10 mM)과 $Arg-NH_2$ (20 mM)와의 Kyotorphin 유도체 합성에 대한 유기용매의 효과에서 ethyl acetate계에서의 합성 수율이 다른 유기용매(dichloromethane, n-butanol, n-hexane, chloroform)에서 보다도 더 높았다. Kyotorphin 유도체의 합성에 미치는 최적조건을 보면, 효소 농도는 10 ${\mu}M$, 온도 및 pH는 각각 $35^{\circ}C$ 및 7.0이었으며, 유기상/수용액상의 비$(\alpha)$는 15였다. Kyotorphin 유도체 합성의 최적 반응조건하에서 수율은 70.2%였으며, 이때의 반응은 24시간 후에 평형에 도달하였다.

• 공업화학
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• 제21권4호
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• pp.357-365
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• 2010

신약개발 과정에서 선도물질을 도출하기 위한 유용한 방법으로 적용되어온 조합합성은 최근 분석과 검사 기술의 빠른 발전과 더불어 다양한 분야에서 응용되고 있다. 특히 분자구조와 특성 간의 상관관계를 예측하기 어려운 신물질 개발 분야에서 다양한 후보 물질들을 빠른 시간 내에 확보하기 위한 효율적인 전략으로 주목받고 있다. 그 동안 조합화학 및 조합합성 기법에 관하여 많은 수의 보고서와 총설들이 발표되었다. 본 총설에서는 조합합성을 이용한 신소재 개발 동향을 간략히 소개하고, 이를 응용한 유기발광재료 개발 사례들을 논의하고자 한다.

• 대한화학회지
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• 제64권1호
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• pp.7-18
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• 2020

An efficient and facile procedure has been developed for the synthesis of novel bichalcone derivatives (4a, 4b). The key step contains the solvent-free aldol synthesis of bichalcones based on quinones. Bichalcones (4a, 4b) were used as precursors for the synthesis of some interesting heterocyclic compounds like, diazepines (5a, 5b), pyrazolo-pyrimidines (7a, 7b), and pyrazoline derivatives (8a, 8b). Moreover, new thioxopyrimidine derivatives (9a, 9b) were furnished and used as a functionalizing agent to produce the triazole-pyrimidines (11, 12) and the carbonitrile derivative (14). All the synthesized compounds were fully characterized using physical and spectral data like, FT-IR, ¹H NMR, ¹³C NMR, and MS. Bichalcones (4a, 4b) and diazepines (5a, 5b) were screened for their anticonvulsant activity, where compounds (4a, 5a, and 5b) revealed potent anticonvulsant activity compared to diazepam. On the other hand, some of the prepared compounds were screened for their antiproliferative activity and they showed significant cytotoxic effects on most of the cancer cell lines with regard to broad spectrum antitumor activity.