• Journal of Applied Biological Chemistry
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• v.49 no.2
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• pp.62-64
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• 2006

• Bulletin of the Korean Chemical Society
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• v.25 no.3
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• pp.417-419
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• 2004

• Applied Chemistry for Engineering
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• v.10 no.4
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• pp.515-522
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• 1999

Asymmetric polyetherimide membrane were prepared by phase inversion method, and the effects of NaOH concentration and reaction time on the morphology change of the polyetherimide membranes were studied. The morphology of skin layers varied from dense structure to sphere structure with increasing concentration of modification solution. The thickness of dense layer increased with increasing reaction time. However, when either the concentration of modifying solution was very high or the reaction time was very long, the dense layers of the asymmetric membrane were disappeared. From these results, it was found that the surface morphology of the asymmetric polyetherimide membranes depended strongly on the modification conditions such as concentration of modification solution and reaction time. These results might be explained by the hydrolysis reaction of polyetherimide into polyamic acid by the NaOH solution.

• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.625-628
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• 2014

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1195-1200
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• 2011

The catalytic enantioselective Mannich-type reaction promoted by chiral binaphthyl-modified bifunctional organocatalysts is described. The treatment of ${\alpha}$-fluoro-${\beta}$-ketoesters with N-Boc imines under mild reaction conditions afforded the corresponding ${\beta}$-aminated ${\alpha}$-fluoro-${\beta}$-ketoesters with excellent enantioselectivities (up to 98% ee).

• Journal of Applied Biological Chemistry
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• v.48 no.2
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• pp.97-100
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• 2005

Chiral dienophile 5 was synthesized from D-glucose by consecutive diisopropylidenation, partial deprotection, diol cleavage, and Wittig reactions. Under thermal conditions, asymmetric Diels-Alder reaction between chiral dienophile and cyclopentadiene gave four possible chiral norbornenes stereoisomers whose absolute configurations were determined through CADD and NMR.

• Archives of Pharmacal Research
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• v.22 no.6
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• pp.624-628
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• 1999

A formal asymmetric synthesis of Mugineic acid was accomplished from cis-2-butene-1,4-diol throughcatalytic Sharpless epoxidation oxidations and doupling reaction.

• Korean Journal of Agricultural Science
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• v.40 no.4
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• pp.367-375
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• 2013

The enzymatic interesterification was performed to produce structured lipids (SLs) with palm mid fraction (PMF) and stearic ethyl ester (STEE) for 1, 3, 6, 9, 12 and 15 hr at $80^{\circ}C$. The reaction was catalyzed by Lipozyme TLIM (immobilized lipase from Thermomyces lanuginosus, amount of 20% by weight of total substrates) in a shaking water bath set at 180 rpm. The optimum condition for synthesis of asymmetric SLs were: substrate molar ratio 1:0.5 (PMF:STEE, by weight), reaction time 6 hr, enzyme 20% (wt%, water activity=0.085) of total substrate and reaction temperature $80^{\circ}C$. After reaction at optimized condition, triacylglycerols (symmetrical and asymmetrical TAGs) from reactants were isolated. POP/PPO (1,3-palmitoyl-2-oleoyl glycerol or 1,2-palmitoyl-3-oleoyl glycerol), POS/PSO (palmitoyl-oleoyl-stearoyl glycerol or palmitoyl-stearoyl-oleoyl glycerol), SOS/SSO (1,3-stearoyl-2-oleoyl glycerol or 1,2-stearoyl-3-oleoyl glycerol) were obtained by solvent fractionation. Finally, refined SLs contained stearic acid of 16.91%. Solid fat index and thermogram of the refined SLs were obtained using differential scanning calorimetry. The degree of asymmetric triacylglycerol in the refined SLs was analyzed by Ag-HPLC equipped with evaporated light scattering detector (ELSD). The refined SLs consisted of symmetric TAG of 41.15 area% and asymmetric TAG of 58.85 area%.

• Journal of the Korean Chemical Society
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• v.60 no.5
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• pp.374-377
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• 2016

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1280-1282
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• 2010

A new chiral catalyst was synthesized and found that it could catalyzed the asymmetric Michael reaction of ketones with nitroolefins smoothly at room temperature, giving the desired adducts in 71 - 92% yields with excellent diastereoselectivities and high enantioselectivities (up to 95% ee).