• Bulletin of the Korean Chemical Society
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• v.23 no.9
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• pp.1277-1320
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• 2002

A novel approach to ${\alpha}-amino-{\delta}-valerolactone$ derivatives 8 by the intramolecular Ugi five-center three-component reaction (U-5C-3CR) using the multifunctional starting material, L-pentahomoserine 5 is described.

• Journal of the Korean Chemical Society
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• v.55 no.4
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• pp.662-665
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• 2011

Highly efficient, three-component condensation of aromatic aldehyde, malononitrile and 4-hydroxycoumarin promoted by neat silica gel at room temperature is described. The method offers an excellent alternative to the synthesis of 3,4-dihydropyrano[c]chromenes. The reactions are fast and clean, and the products are obtained with good yield and purity.

• 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.

• YAKHAK HOEJI
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• v.28 no.3
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• pp.179-183
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• 1984

In the previous paper the isolation of .alpha.-spinasterol and its glucoside from ether fraction of Codonopsis pilosula was reported. In continuation of earlier work, further component was investigated and led to isolation three tirterpenoids. Repeated column chromatography on silica gel of the ether extract resulted in the isolation of taraxeryl acetate, mp $298~301^{\circ}$, friedelin, mp $263~265^{\circ}$, and taraxerol, mp $289~8^{\circ}$. All the compounds were identified on the basis of spectral data and chemical reactions.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2431-2435
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• 2013

A simple and efficient method for the synthesis of spiro[4H-pyran-oxindole] derivatives by means of three-component reactions between isatins, malononitrile or ethyl cyano-acetate, and 1,3-dicarbonyl compounds in the presence of catalytic amount of magnesium perchlorate in 50% aqueous ethanol medium has been described.

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.453-458
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• 2012

Reactions of (N-isocyanimino)triphenylphosphorane with (1R)-(-)-campherchinon in the presence of aromatic carboxylic acids proceed smoothly at room temperature and in neutral conditions to afford sterically congested 1,3,4-oxadiazole derivatives in high yields. The reaction proceeds smoothly and cleanly under mild conditions and no side reactions were observed.

• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.1902-1909
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• 2007

This account reports an overview of our findings in homogeneous Pd-catalyzed reactions. Herein we describe the new design in reactions of Group 14 element compounds and in homogeneous nanosize Pd catalysts. In the early stages of our study, we developed Pd-catalyzed transformations of allylic esters with disilanes, silylcyanides and acylsilanes to the corresponding silylation, cyanation and acylation products, respectively. We also developed a Pd-catalyzed three component coupling reaction of Group 14 element compounds involving 1,3-diene and acid chlorides to form β,γ-unsaturated ketone as a single product. Recently, we focus our attention on modifying the catalytic environment by nanosize Pd in order to improve the performance of Pd catalysts. These nanosystems realize efficient catalytic environment with remarkable enhancement in catalytic activity and unprecedented selectivity.

• Proceedings of the Korean Society of Crop Science Conference
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• 2019.09a
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• pp.148-148
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• 2019

Wheat is a very important crop as a food source worldwide, but gluten in wheat causes a variety of allergic reactions. Previous studies have developed ${\omega}-5$ gliadin deleted O-free, known as the central antigen of WDEIA (wheat-dependent exercise-induced anaphylaxis). In this study, we performed RNA sequencing on the grains and leaves of the allergic-reduced species O-free and their cultivars, Keumkang and Olgeuru, to analyze differentially expressed genes (DEG) based on different cultivars and tissues. Tissues of all species were biologically repeated three times. We used bowtie2 version 2.3.5.1 to get sequence data from RNAseq and used cufflinks and Tophat programs to find DEG. When comparing leaf and grain tissues, a total of 1,244 DEGs were found in the leaf tissues while only 563 DEGs were found in the grain tissues. As a result of gene ontology analysis of differentially expressed genes, the leaf tissues were mostly included in the "catalytic activity" part of molecular function, "metabolic process" part of biological process, and "membrane" part of cell component. The grain tissues were mostly included in the "metabolic process" part of biological process, "binding" and "catalytic activity" part of molecular function, and "membrane, cell, cell part" parts of cell component. Based on these results, we present information on the differentially expressed genes of the three cultivars of leaves and grains. This study could be an important basis for studying the characteriztion of O-free.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.275-281
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• 2014

The ozone depletion has caused plants to be exposed to an increased penetration of solar ultraviolet-B (UV-B) radiation. Enhanced UV-B radiation may have influence on biological functions of plant in many aspects including inhibition of photosynthesis. It is evident that UV-B can potentially impair the performance of all three main component processes of photosynthesis, the photophosphorylation reactions of the thylakoid membrane, the $CO_2$-fixation reactions of the Calvin cycle and stomatal control of $CO_2$ supply. Owing to these depressed reactions, the production and allocation of carbohydrates might be markedly affected, and therefore, the growth and development of plant are distinctly reduced. In this review paper, we provide basic theory and further researches in terms of photosynthesis and carbohydrate synthesis in response to elevated UV-B radiation.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.656-658
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• 2011

A green and efficient method for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones and -thiones through one-pot three-component reaction of ethyl acetoacetate, an aryl aldehyde, and urea or thiourea in acetonitrile using silica gel-supported polyphosphoric acid (PPA-$SiO_2$) as catalyst is described. Compared to the classical Biginelli reaction conditions, the present methodology offers several advantages such as high yields, relatively short reaction times, mild reaction condition and a recyclable catalyst with a very easy work up.