• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3180-3182
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• 2010

A simple facile 'one pot' synthesis of 2-amino-3-cyano-4,6-diarylpyridine derivatives via three component reaction of chalcone, malanonitrile and ammonium acetate under ultrasonic irradiation and grindstone technology. All the synthesized compounds have been characterized on the basis of their elemental analyses and spectral data (IR, $^1H$ NMR, $^{13}C$ NMR and Mass).

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1057-1060
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• 2009

Boric acid ($BO_3H_3$) is an inexpensive, efficient and mild catalyst for the synthesis of 2,4,5-triaryl-1H-imidazoles in excellent yields from the one-pot three-component condensation of benzil/benzoin, an aldehydes and ammonium acetate in aqueous media under ultrasound at room temperature. The remarkable advantages offered by this method are green catalyst, mild reaction conditions, simple procedures, much faster reactions and excellent yield of products.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1054-1056
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• 2009

We have demonstrated a one-pot three component coupling of an aldehydes, an amines, and triethyl phosphite using 1-benzyl-3-methyl imidazolium hydrogen sulphate [bnmim][][$HSO_{4}$] as an efficient catalyst. All the reactions proceed under solvent-free conditions at room temperature. This methodology afforded the corresponding $\alpha$-aminophosphonates in shorter reaction times with excellent yields.

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2140-2144
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• 2012

A polymer support immobilized acidic ionic liquid was prepared by copolymerization of 3-vinyl-1-(4-sulfonic acid)butylimidazolium hydrogen sulfate with styrene in the presence of benzoyl peroxide and its primary application as a solid acidic heterogeneous catalyst to the synthesis of Hantzsch 1,4-dihydropyridines through a one-pot three-component reaction of aromatic aldehydes, ethyl acetoacetate and ammonium acetate was investigated. The results showed that this heterogeneous catalyst has high catalytic activity and the desired products were obtained in good to high yields. Moreover, the catalyst was found to be reusable and a considerable catalytic activity still could be achieved after third run.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3632-3638
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• 2010

2-Iminopyrimidines (1a-e) and 2-thioxopyrimidine (2) were synthesized using the Biginelli three component cyclocondensation reaction of an appropriate $\beta$-diketone, arylaldehyde, and guanidine (for 1a-e) or thiourea (for 2). The electrochemical properties of the novel systems were investigated by CV and DPV. Moreover, B3LYP/6-31G(d,p) method was applied to the present structures in order to gather some structural and physicochemical data.

• 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.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1508-1512
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• 2013

A simple and efficient synthesis of 2,4,5-trisubstituted imidazoles was achieved via a one-pot three-component cyclocondensation of benzil, aromatic aldehydes, and ammonium acetate in the presence of a catalytic amount of tetrabutylammonium hexatungstate $[TBA]_2[W_6O_{19}]$ as a heterogeneous catalyst under thermal solvent-free conditions. The key features of this methodology are operational simplicity, high yields, short reaction times, and a recyclable catalyst with a very easy work up.

• Korean Journal of Applied Biomechanics
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• v.24 no.4
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• pp.359-365
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• 2014

A study was conducted to investigate the possible effects of fatigue which was resulted from increased running time on the stability during a prolonged run. The purposes of this study were twofold: first, to determine the discrete and non-linear variability of GRF (ground reaction force) components between running times to know the body stability, and second, to determine the pattern between discrete and non-linear variability. Nineteens healthy young adult males served in this study as subjects who ran at their preferred running speed. GRF data for twenty strides were collected at 5, 65, and 125 minutes during run. Variance coefficient and Lyapunov Exponent techniques on the GRF data were used to calculate variability index for each of the running time conditions. There were no difference between discrete variabilities of three components of GRF, but non-linear variability of the Fz component of GRF was decreased by increasing running time (p<.01). No relationship was found between discrete and non-linear variability.

• Bulletin of the Korean Chemical Society
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• v.6 no.2
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• pp.86-90
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• 1985

(Z)-13-Eicosen-10-one, an active component of the sex pheromone of the peach fruit moth was synthesized from 4-oxo-tridecan-1-al and heptylidenetriphenylphosphonium ylide by Wittig reaction. The key intermediate, 4-oxo-tridecan-1-al, was synthesized by three different methods. The biological activity test of the synthetic pheromone as attractant for the male peach fruit moth was tested at several districts in Korea.

• Herbal Formula Science
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• v.10 no.2
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• pp.159-188
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• 2002

The purpose of this study was to reseach the effect of Daehwanggamchoeumja(大黃甘草飮子) and its component groups on diabetes, free radicals, and antioxidants system in Alloxan-induced diabetic rats. The experimental group was divided into three groups: Daehwanggamchoeumja(DG), and its components groups, Gamdutang (Gamcho&Daedu; DG-I) and Daehwanggamchotang(DG-2). The results were obtained as follows: 1. In the study of effect on diabetic metabolic dysfunction(Glucose, Triglyceride, Total Cholesterol, HDL Cholesterol, Total Protein, Albumin, Creatine, BUN), only DG has a significant effect. 2. In the study on free radical scavenging effect in vitro(the suppressing effect on peroxidation of linoleic acid on concentration, the scavenging effect of DPPH radical, inhibitory effect of superoxide in xanthine-xanthine oxidase system, inhibitory effect on lipid peroxidation reaction by hydroxy radical in $H_2O_2Fe^{2-}$system, and the effect on Nitrate reductase activity), DG and DG-2 have more effect than DG-l relatively. 3. In the study on antioxidants system in vivo(The level of serum LPO, The level of hepatic LPO, Catalase, GSH, GST), only DG has a significant effect. These results suggest that Daehwanggamchoeumja(大黃甘草飮子) has an effect on diabetes, peroxidative damage by free radical, so it seems to be useful to prevent and treat diabetes. The mechanisms of these are supposed to be involved in antioxidant and three drugs' cooperative synergy effect.