• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2428-2432
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• 2011

A series of new 4-aryl-6,8-dimethylpyrimido[4,5-c]pyridazine-5,7(6H,8H)-diones have been synthesized via three component reaction of 1,3-dimethylbarbituric acid with arylglyoxals in the presence of hydrazinium dihydrochloride in ethanol. All of these derivatives may act as potential monoamine oxidase inhibitors.

• Bulletin of the Korean Chemical Society
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• v.30 no.3
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• pp.551-555
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• 2009

The ytterbium catalyst immobilized on the cross-linked poly(4-vinylpyridine/styrene) copolymer (P/S-Yb) was applied in the Mannich-type, three component one-pot synthesis of $\beta$-aminoketones. This catalytic system showed excellent catalytic activity and selectivity which resulted in the exclusive formation of $\beta$-aminoketone. The applicability of this immobilized catalyst system was shown by the reusability test and again highlighted by the synthesis of a $\beta$-aminoketone library using a broad range of substrates.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.504-507
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• 2002

A separation/purification process for enzymatic sugar ester production was investigated The crude reaction mixture contained sugar ester and unreacted fatty acid in acetone. The reaction mixture was mixed with KOH/phosphate buffer. Hexane was then added to enhance phase separation. Three phases formed: a lower aqueous phase containing nothing of interest, a polar organic solvent middle phase that contained mostly fatty acid soaps, and a hexane-rich upper phase that contained mostly sugar ester. Distribution coefficient of each component was measured.

• Journal of the Korean Chemical Society
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• v.53 no.1
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• pp.90-94
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• 2009

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2573-2576
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• 2014

• Applied Chemistry for Engineering
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• v.3 no.3
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• pp.440-450
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• 1992

Three type extraction processes of rare earth metal component from rare earth metal bearing ore were sulfuric acid digestion, caustic soda leaching and decomposition with $(NH_4)_2SO_4$. From the overall results, both caustic soda leaching and sulfuric acrid digestion were better extraction processes for domestic monazite ore. The proper conditions of sulfuric acid digestion for domestic monazite ore were reaction temperature $210^{\circ}C$, reaction time 40 min, weight ratio of $H_2SO_4$ to monazite ore 1.5 and concentration of $H_2SO_4$ 95%. Under these conditions, 98% of rare earth metal component was extracted and also the reasonable conditions for caustic soda leaching were reaction temperature $140^{\circ}C$, weight ratio of NaOH to monazite 3.0, concentration of caustic soda solution 50% and leaching time 3hrs. Under these conditions, 97% of rare earth metal component was extracted.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.635-638
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• 2011

A simple and efficient method for the synthesis of $\beta$-amino carbonyl compounds by one-pot three-component Mannich reaction of acetophenone, aromatic aldehydes and aromatic amines using a carbon-based solid acid (CBSA), as an effective and reusable catalyst, is described. The present methodology offers several advantages such as simple procedure with an easy work-up, shorter reaction times, and high yields.

• Journal of the Korean Chemical Society
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• v.55 no.5
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• pp.787-793
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• 2011

An efficient three-component one-step synthesis of 2,4,5-trisubstituted imidazoles by condensation reaction of 1,2-diketones or ${\alpha}$-hydroxyketones with aromatic aldehydes and ammonium acetate using Zinc (II) [tetra (4-methylphenyl)] porphyrin as a novel and reusable catalyst under ultrasound irradiation at ambient temperature is described. In this method, ${\alpha}$-hydroxyketones as well as 1,2-diketones were converted to their corresponding 2,4,5-trisubstituted imidazoles in excellent yields.

• Journal of the Korean Chemical Society
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• v.57 no.4
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• pp.472-475
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• 2013

An efficient and environmentally benign protocol for the three-component synthesis of triazoloindazoles and indazolophthalazines via condensation of dimedone, aldehydes and urazole or phthalhydrazide catalyzed by $ZrOCl_2.8H_2O$ as an inexpensive and eco-friendly catalyst with high catalytic activity under solvent-free conditions is reported. This protocol provides a new and improved method for obtaining triazoloindazoles and indazolophthalazines in terms of good yields, simple experimental procedure and short reaction time.

• Journal of the Korean Chemical Society
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• v.59 no.4
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• pp.280-283
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• 2015

Hydrated ferric sulfate can be used as an efficient and reusable catalyst for the synthesis of 2H-indazolo[2,1-b]phthalazine-trione derivatives via one-pot three-component condensation reaction of phthalhydrazide, aromatic aldehydes and cyclic-1,3-diketones in ethanol under reflux conditions.