• 약학회지
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• 제55권2호
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• pp.127-130
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• 2011

We synthesized new ${\alpha}$-amidoketenes using dehydrochlorination from anilines, triethylamine and malonyl dichloride under $0^{\circ}C$. The utility of ketenes in both laboratory and industrial practice was quickly recognized, and these species have been extensively utilized, including as pharmaceutical intermediates and anti-cancer agents. All synthetic process from anilines to ${\alpha}$-amidoketenes could be carried out by one-pot reaction. Synthetic ketenes 2a~f were identified using NMR and IR spectrum. Formation of ketenes was undertaken with dropping of malonyl dichloride at $0^{\circ}C$ in methylene chloride for 0.5~4 h. Using malonyl dichloride was better than using diethyl malonate as a synthetic reagents for the ketenes.

• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.60-64
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• 2012

Silver(I) [bis(alkylthio)methylene]malonates were synthesized from the reaction of silver nitrate and potassium [bis(alkylthio)methylene]malonates. The structures of the Ag complexes were characterized with nuclear magnetic resonance (NMR), inductively coupled plasma atomic emission spectrometry (ICP-AES) and elemental analysis. Ag nanoparticles (NPs) were obtained from the decomposition of the Ag complexes in 1,2-dichlorobenzene at $110^{\circ}C$ without an additional surfactant. The average sizes of the Ag NPs are in the range of 5.1-6.3 nm and could be controlled by varying the length of the alkyl chain. The optical properties, crystalline structure and surface composition of Ag NPs were characterized with ultraviolet-visible (UV-visible) spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), gas chromatography-mass spectrometry (GC-MS), X-ray Photoelectron Spectroscopy (XPS) and thermal gravimetric analysis (TGA).

• Bulletin of the Korean Chemical Society
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• 제31권11호
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• pp.3159-3162
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• 2010

To realize highly selective recognition of oxalate in water, a new chemosensing ensemble that behaves highly selective colorimetric recognition of oxalate in water at pH 7.4 has been developed. The ensemble was constructed by a pyrrole containing mononuclear copper complex and chromeazurol S. The ensemble shows a highly selective recognition of oxalate through an obvious color change from blue to yellow upon the addition of oxalate, whereas, other dicarboxylates such as malonate, succinate, fumarate, maleate, glutarate, adipate, phthalate, isophthalate and terephthalate do not induce any noticeable color changes. The oxalate recognition process is not significantly affected by other coexisting dicarboxylate.

• Archives of Pharmacal Research
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• 제28권2호
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• pp.142-150
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• 2005

The synthesis and structure-activity relationships of a novel series of substituted quercetins that activates peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) are reported. The $PPAR{\gamma}$ agonistic activity of the most potent compound in this series is comparable to that of the thiazolidinedione-based antidiabetic drugs currently in clinical use.

• 대한화학회지
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• 제60권4호
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• pp.257-260
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• 2016

A new perfluorobutyl substituted cyclic type disodium alkanesulfonate is designed, synthesized and characterized as alternative substance to perfluorooctane sulfonic acid (PFOS, 1), a well-known surfactant. Cylic type sulfonate was accomplished from commercially available 2,2,3,3,4,4,5,5-octafluoro-1,6-hexanediol in four steps. Bio-degradable perfluorobutyl moiety was introduced from fluorous diol, which is symmetrically substituted amphiphile via installation of an intermediate trifluoromethanesulfonyl ester and easily manipulated by double displacement of triflate using potassium malonate and further reduction followed by nucleophilic ring opening are key reactions to get target disodium alkanesulfonate. The efficiency and simplicity in the synthesis of this material offer a new strategy to design PFOS alternatives.

• Journal of Microbiology and Biotechnology
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• 제21권11호
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• pp.1143-1146
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• 2011

Metabolic engineering of plant-specific phenylpropanoid biosynthesis has attracted an increasing amount of attention recently, owing to the vast potential of flavonoids as nutraceuticals and pharmaceuticals. Recently, we have developed a recombinant Streptomyces venezuelae as a heterologous host for the production of flavonoids. In this study, we successfully improved flavonoid production by expressing two sets of genes predicted to be involved in malonate assimilation. The introduction of matB and matC encoding for malonyl-CoA synthetase and the putative dicarboxylate carrier protein, respectively, from Streptomyces coelicolor into the recombinant S. venezuelae strains expressing flavanone and flavone biosynthetic genes resulted in enhanced production of both flavonoids.

• 멤브레인
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• 제29권2호
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• pp.111-121
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• 2019

정삼투 공정에 유용한 유도용질로서 diethyl malonate를 사용한 citrate 계열의 유기 화합물을 합성하였다. 최종적으로 얻은 potassium pentane-1,3,3,5-tetracarboxylate는 $^1H-NMR$과 $^{13}C-NMR$을 통하여 확인하였다. 유도용질의 물성을 확인하기 위해 삼투압, 용해도, 수투과도, 역염 투과도를 측정하였다. 합성한 유도용액을 사용하여 정삼투 공정을 진행한 결과, 동일한 citrate 계열인 trisodium citrate 및 tripotassium citrate보다 높은 수투과량을 나타내었으며 염의 역확산 정도는 NaCl에 비하여 매우 낮은 값을 나타내었다. 합성된 유도용질의 삼투압은 NaCl보다 약 25% 낮았으나 물에 대한 용해도는 NaCl의 8.8배인 317 g/100 g water의 값을 나타내었다. 정삼투 종료 후 유도용질의 회수를 위해 상용화된 나노여과막을 사용하였고, 낮은 압력에서 효율적으로 회수가 가능하였다.

• 한국분말재료학회지
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• 제24권5호
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• pp.395-399
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• 2017

Solder paste is widely used as a conductive adhesive in the electronics industry. In this paper, nano and microsized mixed lead-free solder powder (Sn-Ag-Cu) is used to manufacture solder paste. The purpose of this paper is to improve the storage stability using different types of solvents that are used in fabricating the solder paste. If a solvent of sole acetate is used, the nano sized solder powder and organic acid react and form a Sn-Ag-Cu malonate. These formed malonates create fatty acid soaps. The fatty acid soaps absorb the solvents and while the viscosity of the solder paste rises, the storage stability and reliability decrease. When ethylene glycol, a dihydric alcohol, is used the fatty acid soaps and ethylene glycol react, preventing the further creation of the fatty acid soaps. The prevention of gelation results in an improvement in the solder paste storage ability.

• 대한미생물학회지
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• 제22권4호
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• pp.427-433
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• 1987

One hundred and thirty-six strains of Klebsiella pneumoniae were isolated from clinical specimen taken from pediatric patiants at 6 different hospitals and identified, characterized and investigated on the patterns of antibiotic resistance. The 136 strains showed the positive reactions in the 17 tests; Voges-Proskauer, ONPG, cirate utilization, KCN degradation, productions of lysine decarboxylase, acid and gas from glucose, utilizations of malonate, manitol, rhamnose, salicin, sucrose, raffinose, arabinose, lactose, sucrose, inositol and raffinose, but the strains showed the negative reactions in the 8 tests; production of $H_2S$, indole, arginine dehydrolase, ornithine decaraoxylase, phenylalanine deaminase, motility, methly red and gelatin liquefaction. 41 did not utilize dulcitol, and 32 did not utilize adonitol. The 36 out of them produced klebecin. The 136 strains were resistant to ampicillin, 2 to gentamicin, 14 to cephalothin, 16 to chloramphenicol, 8 to kanamycin, 13 to streptomycin, and 17 to tetracycline. Twenty strains were resistant to 2 kinds of antibiotics 5 strains to 3, 4 to 4 and 1 to 6 and 7.

• 약학회지
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• 제34권1호
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• pp.15-21
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• 1990

-4,9-dione derivatives were prepared from $2-chloro-3-({\alpha}-accetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ and 2-chloro-3-N-phenylamino-1,4-naphthoquinone. $2-Chloro-3-({\alpha}-acetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ was reacted with amines to give $2-amino-3-({\alpha}-acetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ derivatives. Subsequent treatment of $2-amino-3-({\alpha}-acetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ with sodium ethoxide gave -4,9-dione derivatives. When 2-chloro-3-N-phenylamino-1,4-naphthoquinone reacted with sodium ${\alpha}-cyano$ ethyl acetate, 2-amino-3-ethoxycarbonyl-N-phenyl--4,9-dione was obtained. However, with sodium diethyl malonate, not -4,9-dione but 2-chloro-3-bis-(methoxycarbonyl)-methyl-2H-3-N-phenylamino-1,4-naphthoquinone was obtained.